Strempel v Wood - [2005] WASCA 163

JURISDICTION : SUPREME COURT OF WESTERN AUSTRALIA

TITLE OF COURT : THE COURT OF APPEAL (WA)

CITATION: STREMPEL -v- WOOD & ANOR [2005] WASCA 163

CORAM: MALCOLM CJ
MCLURE JA
LE MIERE AJA

HEARD: 7 & 8 APRIL 2005

DELIVERED : 29 AUGUST 2005

FILE NO/S: FUL 111 of 2003
FUL 12 of 2004

BETWEEN: BRIAN PHILLIP STREMPEL
Appellant
AND
DAVID JOHN WOOD
First Respondent
JOHN ORESTE CHLEBOUN
Second Respondent

ON APPEAL FROM:
Jurisdiction              :  DISTRICT COURT OF WESTERN AUSTRALIA
Coram  :JENKINS DCJ
Citation  :[2003] WADC 145
File No  :CIV 399 of 2001

Catchwords:

Appeal - Negligence - Medical practitioner - Post operative treatment - Breaching duty of care - Causation - Subsequent negligent administration of antibiotics - Damages

Legislation:

Nil

Result:

The appeal succeeds against both respondents

Category: B

Representation:

Counsel:

Appellant:     Mr C L Zelestis QC & Mr T Lampropoulos
First Respondent           :     Mr J Gilmour QC & Mr E A Panetta
Second Respondent       :     Mr J Gilmour QC & Mr E A Panetta

Solicitors:

Appellant:     Hoffmans
First Respondent           :     Clayton Utz
Second Respondent       :     Clayton Utz

Case(s) referred to in judgment(s):

Bennett v Minister of Community Welfare (1992) 176 CLR 408
Bolam v Friern Hospital Management Committee [1957] 1 WLR 582
Chappel v Hart (1998) 195 CLR 232
Fox v Percy (2003) 214 CLR 118
Halley v Chudleigh [1963] ALR 616
Naxakis v Western General Hospital (1999) 197 CLR 269
Planet Fisheries Pty Ltd v La Rosa (1968) 119 CLR 11
Rogers v Whitaker (1992) 175 CLR 479
Rosenberg v Percival (2001) 205 CLR 434
Sharman v Evans (1977) 138 CLR 563
Tran v Claydon [2003] WASCA 318
Water Board v Moustakas (1988) 180 CLR 491

Case(s) also cited:

Anikin v Sierra (2004) 79 ALJR 452
Hayden v NRMA [2000] NSWCA 374; (2000) 51 NSWLR 1
Jones v Bartlett (2000) 205 CLR 166
Maloney v Commissioner for Railways (NSW) (1978) 52 ALJR 292
March v E & MH Stramare Pty Ltd (1991) 171 CLR 506
Modbury Triangle Shopping Centre Pty Ltd v Anzil (2000) 205 CLR 254

MALCOLM CJ: I have had the benefit of reading in draft the reasons to be published by McLure JA and Le Miere AJA. The relevant facts and circumstances have been fully set out in those reasons. In particular, I respectfully agree with the summary by McLure JA of the facts and the issues raised in the appeal and the cross‑appeal by the second respondent against the assessment of damages for the negligent administration of the antibiotic gentamicin.
McLure JA has convincingly demonstrated that the learned trial Judge was in error in failing to find that the second respondent was negligent to conclude that the conclusion was chronic rather than acute. The error was the result of the application of the wrong approach to the resolution of the issue. As McLure JA has demonstrated, the evidence did not justify a finding that the appellant suffered from pre‑operative ischaemia or had any cause for ischaemia in his right leg. As McLure JA has pointed out, neither of the respondents had received any information to that effect or understood that to be the case. In any event, I agree with McLure JA that the evidence of Professor Tracy was that even if the occlusion was chronic, the ischaemia was an acute event requiring active intervention. What form that intervention should take could be determined by performing an angiogram to determine the nature of the injury to the popliteal artery.
I agree with McLure JA that the weight of the evidence at the trial was that an angiogram can assist in the identification in identifying the nature of an injury to an artery, and that the failure to conduct or arrange for an angiogram to be conducted, using the catheter for the purpose of probing the occlusion was a breach of the standard of care required of an ordinary skilled vascular surgeon. Although the point regarding the angiogram was not specifically pleaded, the issue was one which was raised and fully litigated at the trial without a specific amendment and required to be determined as McLure JA has demonstrated.
McLure JA has demonstrated that the respondents knew, or ought to have known, that had they carried out an angiogram on 25 September, they could have ascertained the nature of the occlusion and, in any event, the nature of the injury could be identified by the use of a wire in accordance with the expert evidence of Mr Milne.
I agree with the analysis by McLure JA of the reasons of the learned trial Judge and her Honour's conclusion that the weight of evidence at the trial supported a finding that, on the balance of probabilities, the nature of the arterial injury and the cause of the occlusion or thrombosis was such

that it could have been successfully aspirated in the course of the angiogram.

I agree with McLure JA that the evidence did not support the conclusion of the trial Judge that progressive ischaemia would have resulted in damage to the appellant's leg by the time the second respondent was in a position to revascularise it.
I am in complete agreement with the balance of the reasons to be published by McLure JA.

Conclusion

It follows that I agree with McLure JA that the appellant's appeal on liability should be allowed, but the appellant's appeal in respect of the quantum of damages should be dismissed and the second respondent's cross‑appeal should be dismissed. I too would wish to hear from the parties whether the case should be remitted to the trial Judge for assessment of damages.
MCLURE JA: The appellant suffered personal injuries as a result of complications following a knee replacement operation performed by the first respondent, an orthopaedic surgeon, on 24 September 1998 at Hollywood Hospital. The second respondent, a vascular surgeon, examined and treated the appellant on 25 September when concerns arose about the adequacy of the blood supply to the appellant's right leg the subject of the surgery. Save for a finding of negligence against the second respondent in relation to the administration of an antibiotic (gentamicin) to the appellant in August to October 2000, the trial Judge otherwise dismissed the appellant's claims of negligence against the first and second respondents.
The facts and findings made by the trial Judge are detailed in the reasons of Le Miere AJA and not repeated here. It is sufficient to provide a short summary.
The first respondent performed the knee replacement surgery (arthroplasty) on the morning of 24 September 1998. Nothing untoward was known to have occurred during the surgery. The appellant returned to the ward with an epidural catheter in situ for the administration of pain relief.
At 7 am on 25 September, the first respondent reviewed the appellant in the course of a ward round. There were no indications of any problems

at this stage. To the contrary, the indications were positive: the appellant told the first respondent that the leg was very comfortable and the first respondent palpated (perceived by touch) the appellant's pedal pulses and his right foot was warm. There are two pedal pulses, the distalis pedis which is in the front of the ankle bone and the posterior tibial which is immediately behind the ankle bone.

From around 10 am on 25 September the appellant's pain began to increase and the hospital notes record that his pedal pulses were absent. At around 1 pm on 25 September the nursing staff telephoned the first respondent and informed him that the appellant was in excruciating pain. The hospital notes for that time record that the appellant's leg was pale, his toes were cool and that sensation and the pedal pulses were absent. The first respondent was in the operating theatre at this time and he asked a registrar, Dr Brankov, to see the appellant. Dr Brankov did so and informed the first respondent that he thought the appellant's leg may be ischaemic (affected by insufficient blood flow). The first respondent instructed Dr Brankov to obtain a specialist vascular opinion, preferably from the second respondent.
The second respondent saw the appellant at around 2.30 pm on 25 September. On examination, the appellant had a popliteal pulse but no pedal pulse. The popliteal pulse is in the popliteal artery. The popliteal artery runs down the back of the leg, continues behind the knee joint and, below the knee, bifurcates into the anterior tibial artery and the posterior tibial artery. The posterior tibial artery gives off to another branch called the peroneal artery.
The second respondent recorded in writing that he suspected that there was a major arterial discontinuity in the appellant's calf from his old war injury. As a result of stepping on a landmine in the course of active duty in the Australian Army during the Vietnam war, the appellant's left leg was amputated above the knee and he suffered injuries to his right leg. The second respondent suggested a duplex scan be performed, an ankle brachial index (ABI) be obtained, the foot be kept down, and Clexane 40 mgm administered. Clexane is an anticoagulant. The first respondent countermanded the suggestion for Clexane because the epidural was still in place. Clexane may produce bleeding at the epidural site.
The appellant had a duplex scan at around 3.30 pm on 25 September. A duplex scan is a diagnostic ultrasound examination. The duplex scan showed that the end of the popliteal artery was completely blocked, that there was no blood flow within all three of the main arteries to the leg below the knee and the ABI was zero. Collateral vessels were present. There was blood flow reconstitution in the right tibial artery at the ankle joint coming in from collateral arteries which joined up with the right tibial artery. The radiologist advised the second respondent by telephone of the results "because of the gravity of the findings". It was clear from the results of the investigations that the appellant had an acutely ischaemic leg. If blood flow was not restored to the ischaemic tissue, the tissue could die and the appellant could lose his lower right leg.
After receipt of the test results, the second respondent examined the appellant at 4.30 pm on 25 September in the presence of the first respondent. Neither the first or second respondent did anything further to investigate, identify or address the cause of the acute ischaemia or take any other measures to restore blood flow. This was described as a conservative approach. In substance, the decision was to do nothing.
In the course of the evening of 25 September the appellant's condition deteriorated. By 1 am on 26 September the hospital notes record that the appellant had severe pain in his right calf and his leg was very swollen. The first respondent was notified. He came to the hospital, examined the appellant, diagnosed compartment syndrome in the anterior tibial compartment and conducted an emergency fasciotomy.
A compartment is a series of muscles separated by fascia (a band of fibrous tissue). Compartment syndrome involves a build‑up of pressure within the compartment which can be caused by a number of factors such as ischaemia, restoration of blood flow or haemorrhage. Compartment syndrome can also cause ischaemia. A fasciotomy is an operation to release the build up of pressure within the compartment to facilitate blood flow.
The trial Judge found that the occlusion of the popliteal artery was acute, not chronic; that the occlusion resulted from an injury to the popliteal artery occurring at the time of the arthroplasty; that the results of the duplex scan and ABI revealed that there was a 50 per cent chance the appellant would lose his lower right leg; and that the second respondent acted (or, more accurately, failed to actively intervene) because he concluded the popliteal occlusion was chronic.
Notwithstanding the risk to the appellant's right leg, it survived. The personal injuries the subject of the appellant's claim include necrosis (death) and debridement (surgical excision) of muscle tissue in the anterior tibial compartment, recurrent infections of the right leg, nerve and muscle damage to the right leg resulting in foot drop and secondary lymphedema. The injuries primarily relate to the compartment syndrome and fasciotomy.
The issues raised in the grounds of appeal are whether the trial Judge erred in:
(1)finding that the respondents were not negligent in failing to diagnose an acutely occluded popliteal artery;
(2)failing to find the respondents were negligent in not performing or arranging for an angiogram and then surgically intervening;
(3)failing to conclude that the respondents' negligence caused the appellant's injuries;
(4)alternatively, in failing to give adequate reasons for the finding that there was insufficient evidence to reach the conclusion that the respondents' negligence caused the injury;
(5)not finding that the first respondent was negligent in offering total knee replacement surgery to the appellant; and
(6)awarding damages for the negligent administration of gentamicin below the range of a sound discretionary judgment.
The second respondent cross‑appealed against the assessment of damages for the negligent administration of the antibiotic. It is convenient to begin with the challenge to the findings that directly relate to the second respondent.

Alleged Breaches of Duty by Second Respondent

One of the central issues in the trial was whether the occlusion in the popliteal artery was long‑standing and pre‑dated the knee replacement surgery (chronic) or sudden and related to the surgery (acute). The trial Judge found that the occlusion was acute, not chronic. There is no challenge to that finding.
The trial Judge rejected the second respondent's explanation given at trial for his conservative approach. His evidence was, in substance, that he recognised that the ischaemia (not the occlusion) had been caused by an acute event but did not surgically intervene to restore blood flow as the benefit of surgical intervention was zero; it was zero because irreversible tissue damage had already occurred in the approximately 30 hours that had elapsed since the surgery which was the cause of the acute ischaemia. His evidence was that nerve and muscle tissue only survive for around six hours once blood flow ceases.
The trial Judge found that at the relevant time (25 September) the second respondent concluded that the occlusion was chronic and, based on that conclusion, believed he could not remove it by surgery. Further, he believed he could not bypass the occlusion because the risk of failure of the bypass was significant and the risk of cutting the collateral circulation when performing the bypass was too high.
However, the trial Judge did not find that the second respondent was negligent to conclude and act on the basis that the occlusion was chronic. She explained why at [290]:
"This is because Professor Tracy, a witness called by the [appellant], who is a well respected, experienced and qualified vascular surgeon with the benefit of more time and more background material has also concluded that the popliteal artery was chronically occluded. My rejection of that conclusion does not mean that the second [respondent] was negligent in arriving at it given the material that he had to work with on 25 September."
In my view, this approach discloses error. A medical practitioner owes his or her patient a duty to exercise reasonable care and skill in the provision of professional advice and treatment: Rogers v Whitaker (1992) 175 CLR 479 at 483 and 489. However, the test for medical negligence is not what other doctors conclude, or say they would or would not have done in the same or similar circumstances; to treat that as decisive is to adopt a variant of the principle in Bolam v Friern Hospital Management Committee [1957] 1 WLR 582. The principle in Bolam, namely that the standard of care owed by a doctor to his or her patient is a matter of medical judgment, was rejected in Rogers v Whitaker at 487, 493. In some circumstances, questions as to the reasonableness of a conclusion or conduct are a matter of commonsense: Naxakis v Western General Hospital (1999) 197 CLR 269 at 275 ‑ 276.
Thus, the fact that a medical expert, even if highly skilled and experienced, reaches the same conclusion as that under challenge, cannot itself justify a finding that the conclusion is within the scope of reasonable medical judgment. The question is whether there is a reasonable basis for concluding that the occlusion was chronic. That requires an examination of the basis on which Professor Tracy reached his conclusion. In concluding that the occlusion was chronic, Professor Tracy relied on information from which he understood that the appellant suffered from pre‑operative arterial insufficiency and ischaemia in the muscles of the leg. The trial Judge concluded that the appellant's evidence fell short of establishing that he suffered from pre‑operative ischaemia or had any cause for ischaemia in his right leg. Moreover, there is no basis for a finding that either the first respondent or second respondent had received information to that effect or understood that to be the case. As noted by the trial Judge, Professor Tracy acknowledged that, but for the pre‑operative history on which he relied, there was nothing to point one way or the other to the cause of the post‑operative ischaemia. The other relevant medical experts agreed that, based on the pre‑operative and immediate post‑operative history, the popliteal occlusion was acute.
The weight of the evidence supports a finding that there were no reasonable grounds to believe that the occlusion was chronic. However, whether or not the second respondent's error is material depends upon whether the cause of the occlusion is relevant to an assessment of what, if any, further action to take in light of the appellant's acute ischaemia confirmed by the duplex scan.
Professor Tracy's evidence was that even if the occlusion was chronic, the ischaemia was an acute event requiring active intervention. His evidence was that the ischaemia was a symptom, or indicated the development, of compartment syndrome and that a fasciotomy should have been performed after receipt of the report of the duplex scan. However, that opinion is inconsistent with the unchallenged finding by the trial Judge that there were no clear symptoms of compartment syndrome before the late evening of 25 September. Further, there is no challenge to her finding that a prophylactic fasciotomy is controversial.
The trial Judge then considered whether the second respondent should have arranged for an angiogram. She said:
"However if I am wrong in my conclusion that it was not negligent to come to the view that the popliteal artery was chronically occluded and to base his treatment on that view, then I accept Mr Milne's evidence that at the very least it was appropriate to perform an angiogram to determine the nature of the injury to the popliteal artery. I also accept that in that process the radiologist or intervening vascular surgeon would normally put a wire down through a tube to poke at the blockage to try and discover whether it was just thrombus or whether it was solid and not able to be fixed. Depending upon the vascular surgeon's assessment a Fogarty catheter may be used or an attempted aspiration may be made."
Mr Milne is a vascular surgeon who was called by the appellant. The trial Judge said that his evidence carried the greatest weight of the vascular surgeons who gave evidence. However, that does not relieve this Court of its duty to make its own assessment of the evidence: Fox v Percy (2003) 214 CLR 118 at [25].
At the hearing of the appeal the respondents contended that the trial Judge erred in finding that an angiogram should have been carried out on the ground that, although it would provide a clearer picture of blood flow in the arterial vessels, it would not determine the nature of the injury or assist the decision as to appropriate treatment.

An angiogram involves passing a catheter through an artery leading to the relevant area of interest in the body and a contrast material is injected to highlight the vessels when x‑rays are taken. It provides a road map of how well blood is moving through the relevant vessels. The placement of wire down the catheter to assess whether the blockage is a soft thrombus or a chronic (hard) occlusion is, in effect, an opportunistic add‑on. Further, an attempt can be made to aspirate the thrombus using the angiogram catheter. This is best explained in the evidence of Mr Milne. Before going to the specifics, it is best to provide the context. Mr Milne's evidence is to the following effect. As a result of the acute ischaemia, there was a grave risk of loss of the appellant's leg. A clinical judgment had to be made at the outset as to whether the limb was viable or unsalvageable. This can be a difficult judgment. If the view is that it is unsalvageable, it can be appropriate not to actively intervene. If it is still viable, it is necessary to assess whether there is a sudden (acute) occlusion or a chronic occlusion because that affects the available treatment options. Mr Milne assessed it to be obviously acute. The next matter to consider is the cause of the occlusion. According to Mr Milne, his presumptive diagnosis was arterial injury as a result of the knee surgery. Then the issue is the nature of the injury. There were a number of theoretical options, including complete or partial transection of the artery or otherwise breaching it; external pressure to the artery causing it to block; or a blunt injury to the wall or lining of the artery causing a thrombus (a stationary blood clot along the wall of a vessel). According to Mr Milne, it is for the purpose of determining the nature of the injury (which affects the possible treatment options) that it is necessary to investigate further by means of an angiogram. Mr Milne was asked about the appropriate response after having received the results of the duplex scan. He said:
"If one intends to give this limb the best chance of surviving, one would do an angiogram which is an insertion [indistinct] in the groin artery, injecting a contrast agent into the artery, following it down with x-ray equipment to delineate the anatomy and the status of the arteries beyond the damaged area.
If that was done in this case, what in your opinion would that have shown?---Well, I think there's very little doubt that it would confirm the occlusion of the popliteal artery which has already been seen on ultrasound. It may show a reasonable artery or it may show no arteries beyond the blockage depending on previous vessel status and whether the clot has extended beyond the area of injury. One would also use an angiogram to try and improve the situation in that a radiologist or intervening vascular surgeon would normally put a wire down under these circumstances and have a poke at the blockage to try and get an idea of whether it was just thrombus or whether it's very solid and not able to be fixed and you can in actual fact quite easily aspirate the clot through the catheter you put in to do the angiogram, thus improving the situation without resorting to surgery and this is normally the first step that we would introduce in this clinical picture and we would ask our radiologist, or if one is the vascular surgeon, to make an attempt to see if we can improve the situation as it stands without making the situation more complex by resorting to other surgical options."
Mr Milne also referred to angiograms performed on the appellant in 2000 and 2002 to identify the nature of the injury resulting in the ischaemia on 25 September. It appears he was shown the angiograms after he had provided his written reports that are in evidence. He said the angiograms provided information as to the nature of the anatomical obstruction and continued:
"… [I]n other words, and I mentioned before that the blockage could be a transection or ligation or a blunt injury to the artery producing lifting up of the lining, something like that, but the advantage of the hindsight here is that now that I have been shown the angiogram I can say that it's more likely that this was a soft thrombus in the artery rather than a transecting injury.
It's a deduction you've made from information that you now have recently available?---Correct.
Looking back as to what might have been the case had an angiogram been conducted in 1998?---That's correct."
I infer from the last question and answer that the same information would have been available if an angiogram had been conducted on 25 September. Further, it is clear from Mr Milne's evidence that his view was that regardless of any clinically based (provisional) assessment of the cause of the ischaemia, the appropriate course is to further investigate by way of angiogram.
It is difficult to clearly identify the conflict, if any, between the evidence of Mr Milne and that given by the respondents' expert vascular surgeon, Mr Lawrence‑Brown. Mr Lawrence‑Brown was also of the view that, based on the pre and immediate post‑operative history, the occlusion was acute. His support for the second respondent's conservative management was based on assumptions that were not proven. Mr Lawrence‑Brown assumed, firstly, that the second respondent had assessed the leg to be viable (that is, it would live) because of collateral circulation. In making that assessment, he assumed that the second respondent had detected movement in the appellant's ankle. He did so because he inferred from the second respondent's management of the appellant that he was not worried about the viability of the leg. In that factual context, he assumed the second respondent had assessed that the risks of surgery were greater than the perceived benefits.
In fact, the trial Judge found that the second respondent conservatively managed the appellant because he concluded that the popliteal occlusion was chronic, in which case it could not be removed by aspiration or a Fogarty catheter and a bypass was too risky. Further, the assumptions made by Mr Lawrence‑Brown were at odds with the second respondent's explanation at trial for his conservative management. He said he assessed that the leg was non‑viable.
Mr Lawrence‑Brown said in cross‑examination that an angiogram (or arteriogram) is indicated "if you have an action intention". The cross‑examination continued:
"But if you're considering your options about whether or not to intervene, wouldn't an arteriogram tell you? I mean, if it's a localised occlusion of a particular spot which might be dealt with by stenting, bypassing or some similar process, wouldn't an arteriogram assist in that?---In most circumstances if you have an acute occlusion and you want to fix it then, yes, you would do an arteriogram and proceed immediately, but if you've already made the decision that you're not going to operate in this situation because the situation is such you can only make it worse, then there's no point in doing an arteriogram at that time.
I see, so the conclusion is: surgical intervention is completely out because I'm going to make it worse; there's no point doing an arteriogram ?---Yes.
But if there's a possibility that it may improve the situation, you proceed immediately to an arteriogram and then proceed according to what that shows?---Yes. You have to make that judgment as you see it - as the person there at the time."
Mr Lawrence‑Brown was re‑examined about the risks of using a Fogarty catheter and aspirating a clot. A Fogarty catheter is a tube with a balloon on the end which is able to be passed down an artery and inflated and is used to retrieve thrombotic material. He identified the risks by reference to the nature of the injury to the artery. If the thrombus was covering a hole in the artery, its removal could result in bleeding into the tissues and exacerbation of the problem. If the wall of the artery was damaged, a Fogarty catheter could disrupt it further. However, he does not say that if the circumstances do not favour conservative management, those risks outweigh the benefit of intervention. Mr Lawrence‑Brown agreed with Mr Milne that the occlusion was a temporary phenomenon.
Mr Milne said that the relevant clinical judgment is in determining whether the limb is at risk and if the answer is yes, then you can do riskier things to save it than if the limb is not at risk. I do not understand Mr Lawrence‑Brown to have a different view. It is at the stage of clinical judgment as to whether the limb is beyond salvation that Mr Milne referred to the differences in ability, intent and "daring‑do" which results in different decisions by different people.
Like Mr Milne, Professor Nade concluded that, as there was no excessive bleeding during surgery, the occlusion occurred through a thrombosis as a result of blunt injury to the wall or lining of the artery during the surgery. He was also of the opinion that the appropriate treatment was to attempt to restore the blood supply to the leg which would be done by surgical exploration and a procedure.
I am satisfied that the weight of the evidence is that an angiogram can be used to assist in identifying the nature of the injury to the artery. The respondents' contentions too narrowly focus on the primary purpose of an angiogram rather than the associated use to which it can be put. The weight of the evidence also supports the trial Judge's conclusion that the failure to conduct an angiogram (or arrange for an angiogram to be conducted) and to use the catheter for the purposes of probing the occlusion is a breach of the standard of care required of an ordinary skilled vascular surgeon.
Before going further, it is appropriate to deal with a pleading point raised by the respondents. They contend the appellant did not plead that the second respondent was negligent in failing to perform an angiogram and in failing to diagnose an acutely occluded popliteal artery. Although that is correct, the issues were in substance joined and litigated in the action and required determination notwithstanding the absence of a formal amendment to the pleadings: see Water Board v Moustakas (1988) 180 CLR 491 at 496, 497.
There is a further step in the trial Judge's analysis and that concerns the appropriateness and results of "surgical" intervention. She addresses that issue correctly, in my view, in the context of causation.
Different legal principles may apply if the issue is related to whether there is a breach or whether the breach caused the damage. When considering whether there has been a breach, knowledge obtained in hindsight (that is, not available at the material time) should form no part of the assessment of what is reasonable in all the circumstances: Rosenberg v Percival (2001) 205 CLR 434 at 441 per Gleeson CJ and 456 per Gummow J. That principle has no application to the question whether the breach caused the damage. However, for the purposes of determining whether there has been a breach, regard can properly be had to what the respondents knew or ought to have known. That includes matters which they would have known if an angiogram had been undertaken on 25 September. To the extent that, as stated by Mr Milne, the results of the angiograms conducted in 2000/2002 are indicative of what an angiogram conducted at the relevant time would have disclosed about the nature of the occlusion, that is not hindsight. In any event, the nature of the injury would be ascertained from the use of the wire in the way indicated by Mr Milne.

Causation

Where, as here, causation arises in the context of an omission, the correct approach is described by Gaudron J in Bennett v Minister of Community Welfare (1992) 176 CLR 408 (at 422 ‑ 443) as follows:
"… where questions of causation depend on hypothetical considerations, allowance should be made, as in the assessment of damages, for the possibility that some event would not have occurred. Possibilities, if they are not fanciful, must be taken into account, at least in a general way, when ever causation or the related issue of prevention is in issue. But questions of that kind are not answered 'maybe' or, even, 'more probably than not'. They are answered 'yes' or 'no' depending on the probabilities for or against. In this respect, they are indistinguishable from the question whether an event happened where possibilities are taken into account but, once the question has been answered, those possibilities have no further bearing on the matter."
If an injury occurs within an area of foreseeable risk, then, in the absence of evidence that the breach had no effect, or that the injury would have occurred even if the duty had been performed, it will be taken that the breach of the common law duty caused or materially contributed to the injury: Bennett v Minister of Community Welfare at 420 ‑ 421; Chappel v Hart (1998) 195 CLR 232 at 257 per Gummow J, 273 per Kirby J; Naxakis v Western General Hospital at 279 per Gaudron J.
The trial Judge found that there were, relevantly, three possible types of surgical interventions, being, in order of increasing degrees of invasiveness, aspiration of the clot (in the course of conducting the angiogram), use of a Fogarty catheter or bypass surgery. The trial Judge found that it would not have been appropriate to attempt to bypass. There is no challenge to that finding. On the question of causation, the trial Judge's reasons are as follows (at [298] to [300]):
"However, the second [respondent] should have performed an angiogram and should have assessed, from the result of the angiogram, the prospects of achieving a positive result from the use of the Fogarty catheter or aspiration. I cannot say whether the results of the angiogram would have been such to justify surgical intervention. Further, after considering all the evidence I am not satisfied that it can be said that the second [respondent's] failure to perform the angiogram and intervene has caused the [appellant's] injuries.
At the time the [appellant] developed ischaemia he had at least a 50 per cent chance of losing his leg whether or not there was surgical intervention. The conservative treatment has resulted in him keeping his leg. There is no doubt he has suffered damage to his leg as a result of the fasciotomy not healing. There is however insufficient evidence before me to prove that those injuries would have been avoided if the second [respondent] had attempted surgical intervention some time after the duplex scan result was obtained. First, revascularising the leg would have led to a greater chance of compartment syndrome occurring through reperfusion. Secondly, if as I accept the leg was gradually becoming ischaemic throughout 24 September and was ischaemic at around 10.30 am on 25 September, the damage to the plaintiff's muscle had in all likelihood occurred by the time the second [respondent] was in a position to revascularise the leg. Thirdly, I accept that any of the techniques that were available to the second [respondent] to use in an attempt to revascularise the leg carried with them their own risks of serious damage to, and even loss of, the leg. These risks were referred to by the second [respondent] and also by Mr Lawrence‑Brown who regarded them as significant enough to warrant a vascular surgeon deciding not to intervene to revascularise a leg.
I also accept the possibility that if an angiogram had been performed it may have revealed to the second [respondent] an occlusion that could not be safely removed. For example, he may have decided that there was such a suspicion that the clot was blocking a hole in the artery that an attempt to remove it was fraught with too much danger. The real possibility that an angiogram and preliminary investigations may have revealed a situation that could not be improved was recognised by Mr Milne and certainly by Mr Lawrence‑Brown."
The trial Judge concluded that she was not satisfied on the balance of probabilities that the failure to conduct an angiogram caused the appellant's injuries. There is no merit in the contention that the trial Judge gave inadequate reasons for her conclusion on causation. They meet the functions and purposes they are required to serve (see Tran v Claydon [2003] WASCA 318 at [35] - [37]).
The opening sentence of the third paragraph above has the potential to be misleading. If it is intended to suggest that the prospects of the appellant losing his leg after the onset of acute ischaemia would remain the same regardless of surgical intervention, the evidence does not support such a finding. The evidence goes no further than that the appellant had a 50 per cent chance of losing his leg if nothing was done.
There are four strands in the trial Judge's analysis that need to be untangled. The first relates to the likelihood of surgical intervention if an angiogram had been performed; the second to the prospects of the intervention being successful; the third to the likelihood of progressive damage; and the fourth is whether, if the occlusion could have been removed and blood flow re‑established, compartment syndrome would have been avoided. This arises because most of the personal injuries the subject of the claim are directly related to the consequences of the compartment syndrome and the surgery (fasciotomy) to address that problem.
Starting with the first two strands. Although the trial Judge found that the second respondent ought to have conducted an angiogram and explored the nature of the occlusion (by placing a wire down the catheter), she said she was unable to conclude whether the results of the angiogram would have been such as to justify surgical intervention or what the prospects of achieving a positive result from an attempt to aspirate the clot or the use of a Fogarty catheter would be, having regard to the risks identified by Mr Lawrence‑Brown.
Mr Milne's evidence was that the post‑arthroplasty angiogram reinforced his impression that the arterial injury was relatively minor in terms of anatomical disruption, that the cause of the anaemia was largely a thrombotic event and therefore would be more than likely amenable to endovascular technology to alleviate it such as sucking the clot out at the time of the angiogram. This evidence supports a finding that aspiration was appropriate and would on the balance of probabilities have been successful. The conclusion is consistent with Professor Nade's evidence referred to earlier. Further, although Mr Lawrence‑Brown referred in general terms to the risks of aspiration, he did not quantify the risk or state that it justified inaction if his assumptions that justified conservative action were misplaced. The mere identification and existence of the possibilities on which the trial Judge relies does not answer the relevant question which is whether the breach did, on the balance of probabilities, cause the damage.
In my view, it was open to the trial Judge and the weight of the evidence supports a finding that, on the balance of probabilities, the nature of the arterial injury and the cause of the occlusion (thrombus) was such that it could have been successfully aspirated in the course of the angiogram.
The third strand relied on by the trial Judge was that progressive ischaemia would have resulted in damage to the leg by the time the second respondent was in a position to revascularise it. I assume that is shortly after the receipt of the results of the duplex scan and ABI. There is no evidence to support a finding (and no finding made) that irreversible damage had occurred to the appellant's muscle by around 4.30 pm on 25 September. The evidence is to the contrary. Irreversible damage can occur after six to eight hours from the onset of acute ischaemia. There were no indications of ischaemia at 7 am when the appellant was reviewed by the first respondent. The first indications were at 10 am on 25 September and the symptoms were acute by about 1 pm on that day. There is no reasonable basis for a finding that irreversible damage had occurred by the time the second respondent ought to have acted.

The next issue is whether the failure to intervene and restore blood flow caused or materially contributed to the compartment syndrome. The trial Judge accepted Mr Lawrence‑Brown's evidence that the appellant's compartment syndrome was caused by the acute ischaemia precipitated by the occlusion of the popliteal artery. There is no challenge to that finding.
The trial Judge relies on the risk of compartment syndrome from reperfusion. There is no evidence that the risk of reperfusion‑caused compartment syndrome was such as to justify inaction. Mr Lawrence‑Brown's evidence was that it was necessary to be alive to, and watch for, symptoms of the syndrome but that it is uncommon to get compartment syndrome where blood flow is re‑established in an acute situation. In this case, the trial Judge noted that the care and attention given by hospital staff to the appellant on the evening and night leading to the development of compartment syndrome was inadequate. The weight of the expert evidence (and that of the second respondent) was that active intervention was the normal course in the case of an acute occlusion. That being the case, it is more likely than not that restoration of blood flow could be achieved without causing compartment syndrome.
It was not suggested that the failure to re‑establish blood flow within a reasonable time after 4.30 pm on 25 September did not increase the risk of developing ischaemia‑caused compartment syndrome. Further, I do not understand the second respondent to contend that the injuries could not be relevantly caused by the negligent omissions if (as is the case) the purpose of the active management contended for was to save the leg which was achieved by natural means. That would seem to be consistent with Chappel v Hart (1998) 195 CLR 232.
I am satisfied that the weight of the evidence justifies a finding that the breaches by the second respondent caused the injuries the subject of the action.

Whether First Respondent Negligent

The pleaded breach is to the effect that the first respondent failed to have due regard to the appellant's leg symptoms on 24 and 25 September 1998 which required investigations and/or surgery to restore blood supply.
The trial Judge's findings are as follows (at [275]):
"I find that once the first [respondent] had obtained the second [respondent's] opinion he was almost bound to follow the second [respondent's] advice with respect to vascular treatment as he was the expert. I accept Professor Nade's view in this regard. I do not accept that the first [respondent] could not question the second [respondent's] proposed treatment and it is a mystery to me why there was not further discussion between them as to possible treatment to increase the [appellant's] chances of keeping his leg and avoiding complications of the ischaemia. Nonetheless I am not persuaded that the first [respondent's] reliance upon the second [respondent's] advice which was not to surgically intervene, was negligent."
In dismissing the claim against the first respondent, the trial Judge also relied on her conclusion that the second respondent was not negligent in failing to investigate and surgically intervene. The second ground for dismissing the claim against the first respondent falls away.
The first respondent's evidence was that in his conversations with the second respondent on the afternoon of 25 September the second respondent said he thought the appellant's ischaemia was due to old trauma and that he did not think a bypass was a viable option. The first respondent said he accepted the second respondent's view because, in his opinion, the vascular management of the appellant was the second respondent's responsibility. Further, because he was of the view that vascular management was the second respondent's responsibility, he did not explore other options with the second respondent as to the treatment of the ischaemia or question the second respondent's opinion or institute any vascular treatment of his own. The first respondent did not give his opinion as to the cause of the ischaemia or the compartment syndrome.
There are obvious difficulties with the first respondent's evidence concerning his alleged transfer of responsibility for the vascular management for the appellant to the second respondent. The second respondent ordered Clexane and that was countermanded by the first respondent. The first respondent reviewed the appellant with the second respondent at around 4.30 pm and then later that evening. It was the first respondent who took responsibility for, and carried out, the fasciotomy in the early hours of 26 September.
Further, it is evident from the extent of the evidence of the orthopaedic surgeons, Professor Nade and Mr Hill, that the identification of the existence and cause of vascular problems following orthopaedic surgery is within the skill and expertise of an orthopaedic surgeon. That is to be expected having regard to the trial Judge's finding that there was a five per cent risk of serious thrombosis following arthroplasty. Further, it was the first respondent who had a great deal of information obtained before, during and after the surgery that was relevant to an assessment of the cause and nature of the ischaemia. For example, his pre‑operative work‑up did not disclose arterial insufficiency or anaemia, there was no bleeding during surgery which would indicate that an artery had been cut and, finally, on the morning of 25 September there were no symptoms of ischaemia.
In addition, Professor Nade's opinion is an inadequate foundation for a conclusion that the first respondent was bound to follow the second respondent's advice. In particular, Professor Nade's evidence is not to the effect that the first respondent was bound to follow the second respondent's "advice" with respect to vascular treatment. The clear thrust of his evidence is that it is preferable for the surgical procedures (that is, treatment, including a fasciotomy) to be carried out by a vascular surgeon. That falls well short of being almost bound to accept the vascular surgeon's assessment of the cause of the problem which, as the trial Judge found, dictated his action in this case.
In the circumstances as they occurred, the appellant should have had the benefit of the two specialists applying themselves to the issues and contributing to the assessment. The first respondent made no contribution. He had personal knowledge of matters relating to the cause of the occlusion. It can be inferred that the first respondent would know, like Professor Nade, that the usual treatment for an acute ischaemic event was an angiogram and active intervention. If he had acted reasonably, he would at the time of the 4.30 pm consultation have raised with the second respondent the relevant facts of which he was aware and the reasonableness of the second respondent reaching and acting on the conclusion that the occlusion was chronic without going the next step and obtaining an angiogram. There is no reason to believe that a professional colleague such as the second respondent would refuse to review or alter his position if cogent information was provided by the first respondent. It is unnecessary in this case to determine who has the ultimate responsibility in the event of a difference of opinion as to the appropriate course of action. I am satisfied that the first respondent was negligent in abdicating his shared responsibility to assess the appropriate response to the acute ischaemia.

Negligence in Offering Surgery

The claim the subject of this ground of appeal was not pleaded. However, it was raised in closing as a result of evidence given by the first respondent to the effect that he offered to perform the total knee replacement surgery because he thought the applicant was severely disabled; in particular, he thought the appellant had constant, severe pain and a useless limb. The appellant contended in closing that the first respondent negligently overestimated his disability, the leg not being as severely disabled as the first respondent understood. The appellant says the trial Judge erred in failing to draw the inference that, if the first respondent had understood the appellant's actual degree of disability, he would not have offered the surgery to the appellant.
This goes beyond the question of the technical availability of the surgery. It goes to the question of whether a medical practitioner, having (as the trial Judge found) warned the patient of all of the relevant risks, should go further and, in effect, remove the decision‑making from the patient because of a personal view that the risks outweigh the potential benefit of the procedure.
However, it is unnecessary to address that novel question because I am not persuaded that the issue was in substance joined and litigated by the parties such as to require determination (Water Board v Moustakas (above)). If it had been, the first respondent would have had the opportunity to give direct evidence on the issue. Further, what the trial Judge found as to the extent of the appellant's disability is not determinative. It is relevant to know whether the first respondent had reasonable grounds for his assessment, based on the history given to him by the appellant and his observations.
I would dismiss this ground.

Gentamicin Damages - Appeal and Cross‑Appeal

The trial Judge assessed damages at $131,846 for the admitted liability in respect of the negligent administration of gentamicin as follows:
Past Loss of earnings  $    7,751.00
Interest thereon  $      465.00
Future Loss of earnings  $ 13,500.00
Past Gratuitous and paid services                  $ 20,465.00
Interest thereon  $    1,228.00
Future Gratuitous and Paid Services              $ 26,437.00
Special Appliances  $    2,000.00
Home modifications  $ 10,000.00
Rest and Recreational needs  $ 10,000.00
General damages  $ 40,000.00
Total$131,846.00
The appellant developed symptoms of giddiness, vertigo, imbalance, nausea, hearing loss and tinnitus as a result of gentamicin‑induced toxicity. The effects are permanent and nothing can be done to alleviate them beyond teaching the appellant to be more dependent on other senses to help compensate for the loss of balance. In addition, failure of concentration can result in the breakdown of the compensatory mechanisms. It is more difficult for the appellant to walk, particularly if tired or distracted. The condition also affects his ability to negotiate steps and drive, particularly when tired, distracted or at night.
The appellant now uses two crutches to walk. But for the effects of gentamicin, the appellant would have learned to walk again without crutches. The use of crutches has resulted in symptoms in the appellant's wrists, arms and shoulders.
The appellant has a prosthetic left leg, and stiffness and foot drop in his right leg. Physical balance is difficult for him. These problems are exacerbated by the gentamicin‑caused vestibular injuries. That is significant because damages depend on the consequences of the injuries for the individual rather than their anatomical nature: Halley v Chudleigh [1963] ALR 616 at 619. However, the trial Judge had regard to all of the relevant factors, including the impact of the compensable injuries in the context of his existing disabilities. I am not persuaded the award of $40,000 for general damages is so far outside the permissible range as to be manifestly inadequate or disproportionate to the injuries received (see Sharman v Evans (1977) 138 CLR 563 at 565).
The appellant and the second respondent challenged the award of damages of $21,251 for past and future loss of earning capacity. The appellant contends it is manifestly inadequate and the second respondent contends there was no, or no sufficient, evidence to warrant awarding any damages under this head.
As the trial Judge observed, she had difficulties differentiating between the appellant's problems related to his landmine injuries and the arthroplasty and its complications as opposed to the antibiotic‑related injuries. The evidence relating to damages did not clearly differentiate between the gentamicin‑related effects from the other causes. Although this made the Judge's task difficult, mere difficulty in making an assessment does not relieve the Court of its duty to do so. However, the difficulties make it harder for the appellant and the respondents to successfully challenge the award.
In May 2000, after his arthroplasty‑related injuries but before the gentamicin‑caused injuries, the appellant elected to seek early retirement from his then employer, the Department of Commerce and Trade. He retired from that employment on 25 August 2000.
The second respondent relies on the fact that Dr Merrick, a rehabilitation specialist called on behalf of the appellant, did not expressly attribute any loss of earning capacity to the effects of the gentamicin. The absence of expert evidence does not prevent an award for loss of earning capacity. The evidence was, and the trial Judge found, that although the appellant gave up his employment with the Department of Commerce and Trade on 25 August 2000 as a result of the arthroplasty‑related injuries, he continued to work from home undertaking part‑time consultancy work. The appellant has tertiary qualifications, is well motivated, determined and articulate. He was highly thought of by his previous employers. The trial Judge found that the gentamicin effects reduced the appellant's earning capacity by, inter alia, reducing his speed, mobility and concentration, as well as the amount of time he was able to devote to his consultancy. The finding is clearly open and reasonable.
The trial Judge concluded that the gentamicin‑related disabilities resulted in a 20 per cent diminution in earning capacity which had already been greatly reduced after the arthroplasty. She expressed this in dollar figures by saying that, were it not for the injuries, the appellant would have been able to earn 20 per cent more than he actually earned. The Judge used the appellant's income for the year ending June 2001 (adjusted to reflect that he only had the gentamicin injuries for 83 per cent of that year) as the basis of the calculation for past and future loss of earning capacity. I am not persuaded there is any methodological error in the approach.
The appellant and the second respondent also challenge the award for paid and gratuitous services (past and future), home modifications and rest and recreation needs. The appellant additionally challenges the award for special appliances and future medical treatment. The appellant's challenge is based on a number of matters, the first of which relates to the Judge's rejection of a claim that the gentamicin injuries would result in the appellant using a wheelchair earlier than he otherwise might. The Judge said she was not persuaded the need for a wheelchair was caused by the appellant's antibiotic‑caused injuries as opposed to his landmine injuries or his arthroplasty complications. She did not make a finding that polyarthralgia in his arms and shoulders would be aggravated by crutches so that he would not be able to use them and would have no alternative but to use a wheelchair. She accepted a rolled‑up submission to that effect for the purposes of considering whether the use of a wheelchair would affect the appellant's earning capacity. The appellant's remaining submissions in relation to these matters are in the nature of assertions.
The respondents, on the other hand, rely on the failure of the evidence as a whole to isolate the effect, if any, of the gentamicin‑related

injuries. I am satisfied that those injuries do materially add to the extent of the appellant's requirements for the services and other needs. However, having regard to the obvious difficulties in quantifying these matters, I am not persuaded that either party has demonstrated appealable error. I would dismiss the appellant's challenge to the assessment of damages and the second respondent's cross‑appeal.

Conclusion

I would allow the appellant's appeal on liability, dismiss the appellant's appeal from the assessment of damages and dismiss the cross‑appeal. I would hear from the parties as to whether the matter can be remitted to the trial Judge, Jenkins J, for an assessment of damages.
LE MIERE AJA: This is an appeal from a judgment of a Judge of the District Court in an action in which the appellant claimed damages for personal injuries. The appellant alleged he received the injuries as a consequence of the negligence of the respondents in connection with right knee replacement surgery that the first respondent performed on 24 September 1998. Each of the respondents denied that he was negligent except that the second respondent admitted liability in respect to the negligent administration of the antibiotic, gentamicin, for the period 3 August to 3 October 2000. The learned trial Judge concluded that the appellant had not established any of the allegations of negligence other than the negligent administration of gentamicin by the second respondent. The learned trial Judge ordered that the appellant's claim against the first respondent be dismissed and there be judgment for the appellant against the second respondent in the sum of $131,846.
In the principal appeal, FUL 111 of 2003, the appellant appeals against the findings of the trial Judge that the appellant had not proved any of the allegations of negligence other than the negligent administration of gentamicin by the second respondent. The appellant submits that the learned trial Judge should have found that each of the respondents was negligent in the post‑operative treatment of the appellant. The appellant submits that the judgment should be set aside and there should be judgment for the appellant against the respondents for damages to be assessed. The appellant further appeals against the award of damages made by the learned trial Judge in relation to the negligent administration of gentamicin. The appellant submits that the damages awarded were inadequate and below the range of a sound discretionary judgment.

The respondents' cross appeal on a number of grounds that collectively argue that the damages awarded in respect of the negligent administration of gentamicin were excessive.
In appeal FUL 12 of 2004 the appellant raised two issues. One concerned the learned trial Judge's award of costs. The second was in substance whether the learned trial Judge had jurisdiction to amend par 276 of her reasons and issues about the manner in which her Honour made the amendment. The appellant did not pursue that appeal and it is not necessary to say anything further about it.

The Facts

The following facts were found by the trial Judge and are not challenged on appeal or are clearly established by the evidence and not in dispute.
The appellant was born on 22 February 1945. He joined the Royal Australian Army in 1964. He was posted to Vietnam as a Second Lieutenant. On 28 August 1967 he stepped on a landmine and suffered injuries to both his legs. His left leg was initially amputated at the knee. Later it was amputated above the knee to enable a prothesis to be more easily attached to it. The appellant also suffered permanent injuries to his right leg. His right knee was left with only a few degrees of flexion and he lost half his right calf muscle. Multiple pieces of shrapnel and other material remain within his right leg.
The appellant was repatriated to Perth and in 1968 he resumed normal duties with the Army. Over the next few years the appellant had two children to his first wife and graduated with a Bachelor of Commerce from the University of Western Australia. In the early 1970s the appellant was posted to Canberra. In 1973 he resigned his commission as a captain in the Army.
By this time he was able to walk using a prosthesis on his left leg and no other aids. Between 1973 and 1998 the appellant had a number of different occupations including working for the Swan Brewery as a market research manager and periods running his own liquor store and a tavern. By 1998 the appellant was working for the Western Australian government in the Department of Commerce and Trade as a Level 7 manager. This employment required the appellant to travel throughout the State and Australia, which he managed to do.

Throughout this period the appellant suffered varying amounts of pain in his right knee. Now and again he asked doctors whether there was any advancement in medical technology that would enable something to be done about his problems in his right knee. Up until 1997 the answer was "no" but at that time he asked a doctor and the doctor suggested that the appellant see the first respondent about having an arthrodesis, that is surgery to fuse the knee joint. The appellant saw his general practitioner who referred the appellant to the first respondent asking the first respondent to speak to the appellant about options for his knee.
The first respondent is the Professor of Orthopaedic Surgery at the University of Western Australia and is a consultant at Hollywood and Sir Charles Gairdner hospitals. He is a very well qualified and experienced orthopaedic surgeon.
The appellant consulted the first respondent on 2 September 1998. The appellant told the first respondent that pain would result from long standing and then the knee flexing. The appellant said that he coped with the swelling and pain by lying down and elevating the leg. The appellant said that after about 20 minutes of elevation the foot would become painful. The appellant said that he was exploring having the knee fused to prevent any flexion and thereby hopefully prevent any pain.
The first respondent told the appellant that a total knee replacement was an alternative to a fusion. The first respondent gave the appellant a booklet entitled "Total Knee Replacement Information Book" ("the booklet") which is a standard Hollywood Hospital publication for arthroplasty, that is joint replacement, candidates. The booklet explains that more than 90 per cent of arthroplasties are trouble free and successful. It states that in 5 per cent of patients the results are not satisfactory and that some complications can be put right by further surgery and some may not. Immediate complications include death (in about 1 per cent of patients), major post‑operative illness such as pneumonia, reaction to drugs or some other generalised problem. There is no specific reference to vascular complications. The booklet says that thrombosis, that is the formation of a blood clot, in the leg occurs in between 25 to 50 per cent of patients but is usually trivial and can be ignored. Serious thrombosis, with major problems in the leg or in the lungs, occurs in about 5 per cent of cases. Death from thrombosis, or from fat getting into the bloodstream, or from a heart attack, or from some other reason occurs in about 1 to 2 per cent of patients having a knee replacement.
The first respondent did a neurovascular examination that included looking at the muscles and a vascular examination that involved feeling the pulses. The relevant pulses are the pedal pulses and the popliteal pulse. There are two pedal pulses. One is called the distalis pedis, which is in the front of the ankle bone. The other is called the posterior tibial, which is immediately behind the ankle bone. The popliteal pulse is in the popliteal artery which runs behind the knee. All three pulses can be difficult to palpate, that is perceive by touch, even by experienced practitioners. The first respondent found the pedal pulses and the popliteal pulse to be present.
The first respondent said that prior to a decision whether or not to have the operation the appellant would need to undergo some further tests. One of the tests was to check out the condition of the bone at the joint and the other test concerned the skin at the back of the knee. As a result of the landmine explosion the skin was adhered to the back of the knee and the first respondent was concerned that that skin would not rupture when the knee was flexed. The first respondent referred the appellant for an MRI scan and a consultation with Dr Fiona Wood, a plastic surgeon, for an opinion as to the relative value of a flap to use as a skin graft over the surgical incision and the possibility of cultured skin to improve his healing after an arthroplasty. This request was for an opinion about the value of the skin the first respondent thought he may need to use to close the surgical incision and not a request related to the general sufficiency of the vascularity of the appellant's right knee for surgery.
The first respondent also undertook, or arranged for, investigations to ascertain whether there would be a metal mismatch and electrolysis between the shrapnel in the appellant's leg and the metal used in the replacement knee.
A second consultation between the appellant and the first respondent took place on 11 September 1998. The first respondent informed the appellant that the metals remaining in his right knee were not incompatible with those in the proposed replacement knee and that the scans and x‑rays had revealed that the operation was feasible. The first respondent mentioned to the appellant that he was at greater risk of complications because of the existing injuries to his right leg.
The first respondent considered that the vascular examination of the appellant was normal and therefore there was no need to get a vascular opinion. The first respondent considered but did not explore the possibility that the appellant may have had arterial disease because he looked in the notes of the Department of Veteran Affairs on the appellant to see if there was any indication that he had had popliteal artery damage and found none. He also could feel the appellant's pulses. Further, he was given no history of arterial disease. The first respondent did not offer the appellant an arthroplasty at the time of the second consultation. He was still awaiting the opinion of Ms Fiona Wood.
On 17 September 1998 Ms Wood gave an opinion. She said that she did not think that an arteriogram (also called an angiogram), that is radiographic exploration of the arteries, was necessary as the flap should not affect the vascularity of the area.
During a telephone conversation between the appellant and the first respondent prior to 23 September 1998 the first respondent offered an arthroplasty to the appellant and the appellant said that he wanted to proceed with the surgery.
The appellant was admitted to hospital on 23 September 1998. On the morning of 24 September, the first respondent performed an arthroplasty on the appellant's right knee. The surgery itself was relatively uneventful. The surgery was performed under an epidural anaesthetic which remained in place upon the appellant's return to the ward. This was to enable the appellant to receive anaesthetic pain relieving medication following the surgery. After surgery the appellant's pedal pulses were palpable and recorded as being strong. The appellant's right knee was on a continuous passive motion ("cpm") machine. This moved the appellant's right leg in an arc of 30 to 60 degrees.
In accordance with the usual procedure, upon the appellant's return to the ward a vascular observation chart of his right leg was kept by the nursing staff. On the morning of 24 September the first entry records the pedal pulses as faint. Then through to 2.00 pm the appellant's pedal pulses were recorded as strong. At 3.00 pm they are recorded as faint. The vascular observation chart also records observations of skin colour, skin temperature, sensation, movement and a pain score. At all relevant times the appellant was receiving epidural pain relief and the epidural drugs may have affected his appreciation of pain. However, the recorded observations tended to a conclusion that despite the presence of epidural pain relief the appellant was experiencing pain in his knee or leg.
The observations of the pedal pulses being faint, even when measured with a Doppler, continued from 3.00 pm on 24 September through to 9.00 pm that evening. A Doppler is a hand held instrument used to examine the blood flow in arteries and veins in the leg using ultrasound. No observations of the pedal pulses were recorded between 9.00 pm on 24 September and 2.10 am on the morning of 25 September. At that time the pedal pulses were again recorded as being faint with Doppler. There is no further recording until 4.50 am when the words "very hard" and "Doppler not available" are recorded on the chart. The words "very hard" mean that the nurse found the pedal pulses very hard to find by palpation because they were either very faint or absent. The next recording on the vascular chart is at 6.10 am. At that time there is no entry for the pedal pulses.
The first time the first respondent saw the appellant after surgery was at approximately 7.00 am on 25 September. The appellant told the first respondent that the leg was very comfortable. The first respondent adjusted the angle of the cpm machine so that it was further flexing the knee. The first respondent felt the appellant's pulses and they were present. The first respondent thought that the appellant had venous return and his foot was warm. In his evidence, the first respondent said that if the pedal pulses were able to be palpated then this would have amounted to an ABI (ankle brachial index) of about 1 which is normal. It was his view that whether or not the pulses were hard to palpate or faint was irrelevant as long as they were present and there were other positive signs such as venous return and warmth. The first respondent was not told by the appellant, the nursing staff or the junior doctors of any problems.
The next entry in the vascular chart on 25 September is at 10.00 am when it is noted that the toes were cool, there was 3 out of 10 pain on movement and the pedal pulses were absent. The epidural nursing notes indicate that that level of pain continued until 12.45 pm when the pain was 10 out of 10 on movement. Dr Boris Brankov, a registrar and resident medical officer, was informed. There are entries for 10.30, 10.50 and 10.55 am. However, at these times there are no observations regarding colour, temperature, movement, sensation and pain. There are two entries recording that the pedal pulses were again absent. Dr Brankov felt the popliteal artery and heard it on Doppler. The popliteal artery runs down the back of the leg from approximately two‑thirds of the way down the femur. It continues behind the knee joint and below the knee it bifurcates into the anterior tibial artery and the posterior tibial artery. The posterior tibial artery quickly gives off another branch called the peroneal artery. The palpation of a pulse in the popliteal artery is not inconsistent with a blockage in the popliteal artery if Dr Brankov felt the popliteal pulse above the blockage. The learned trial Judge found that that is what occurred.
Dr Brankov did not inform the first respondent at this time of any problem with the appellant's right leg.
The hospital notes record that on 25 September at noon and 1.00 pm the colour of the appellant's leg was pale, toes cool, movement present, sensation absent and pedal pulses absent.
At approximately 1.00 pm the nursing staff rang the first respondent whilst he was in the operating theatre at Hollywood Hospital and advised him that the appellant was in excruciating pain. The first respondent sent Dr Brankov to see the appellant. Dr Brankov examined the appellant. Dr Brankov reported back to the first respondent that he was concerned about the blood supply to the appellant's leg and he thought that it might be ischaemic, that is affected by insufficient blood supply. The first respondent told Dr Brankov to get a specialist vascular opinion, preferably from the second respondent.
The second respondent is a surgeon practising in general and vascular surgery. He is a consultant at Hollywood Hospital. He is a very well qualified and experienced surgeon. His specific areas of interest include collateral circulation and stimulation of the collateral circulation.
Within an appropriately short period of time the second respondent examined the appellant. There is a written referral to and reply from the second respondent on the hospital file. The request to the second respondent was to "review his vascular supply to the lower leg, if it has been compromised?" When the second respondent first examined the appellant's leg in the afternoon it was white and cold. There was a lack of movement, sensation and no pedal pulses. His view was that because the appellant had a popliteal pulse and no pedal pulses there had to be discontinuity of blood flow between those two levels. To find out the nature and extent of that he suggested a duplex scan. The written reply of the second respondent dated 25 September states as follows:
"I suspect that he has major arterial discontinuity in the calf from his old injury.
Suggest:
1.Duplex scan and ABI.
2.Keep foot down.
3.Clexane 40 mgm bd.
Microvascular thrombosis after protracted elevation is a real possibility and must be prevented at all costs."
Dr Brankov reported to the first respondent that he had put the leg down flat and that he was organising the duplex scan. A duplex scan is a diagnostic ultrasound examination. The first respondent told Dr Brankov not to implement the Clexane treatment until the first respondent had reviewed the appellant. This was because the first respondent was concerned about the effect of Clexane, an anticoagulant, on the epidural site. Whilst an epidural is in place Clexane may produce bleeding at the epidural site.
The hospital notes record that at 2.00 pm the colour of the appellant's leg was pale, the temperature warm, movement present, sensation absent and no entry for the pedal pulses and a remark that there was popliteal on Doppler.
The appellant had the duplex scan in reasonable time some time after 2.00 pm. The person who conducted the scan provided a report. The report says, in effect, that the superficial femoral artery, the main artery to the leg, and the first part of the popliteal artery were of normal calibre and size and had a normal wave form, suggesting they had normal soft walls. There was fairly minor arterial disease present in the middle section of the popliteal artery, causing a 40 per cent narrowing of its calibre. At the end of the popliteal artery, it was completely blocked. There was no blood flow within all three of the main arteries to the leg below the knee. Collateral vessels, known as the geniculate vessels, which are the small arteries around the knee, were pitted. There was flow reconstitution in the right posterior tibial artery at the ankle joint. The report commented on the different wave form created by perfusion, that is a flow of blood to reach tissue, by collateral blood vessels and there was no arterial flow. If blood flow was not restored to the ischaemic tissue the tissue would die.
The radiologist advised the second respondent by telephone of the results of the duplex scan because of "the gravity of the findings". The second respondent's provisional treatment was to put the leg down in order to use gravity to encourage blood flow and to suggest anticoagulant treatment, that is Clexane.
The second respondent regarded his suggested treatment as a standard, conservative course. He discussed it with the first respondent around 4.30 pm. The second respondent acknowledged that there were complications with using Clexane as it may result in bleeding into the site of surgery and in the epidural space if the appellant still had an epidural catheter inserted. The second respondent considered that it was not up to him to decide whether, for example, to remove the epidural catheter as the appellant was not his patient, he was only providing a vascular opinion.
The second respondent explained his reference to microvascular thrombosis in his written note to be a reference to thrombosis of the smaller arteries coming from the tibial arteries. He said that once thrombosis occurred in these arteries and eventually also on the venous side there was an irretrievable situation. I take that to mean irreversible loss of blood flow to the tissue leading to death of the tissue. He said that this process occurred within hours.
The learned trial Judge found that this is consistent with the second respondent believing that the popliteal artery was chronically occluded and therefore placing importance on the collateral system.
As to whether it was appropriate to surgically intervene, the second respondent gave evidence that he thought that the only way to save what was not irretrievably damaged in the leg, was by a conservative approach. This was because the benefit he saw in surgical intervention was zero and the risk was very high. He thought that the benefit was zero because at the time what was damaged was already damaged irreversibly because of the 30 hours or thereabouts time lapse since the arthroplasty. Nerve and muscle which had been deprived of blood would have only survived for six hours once the blood flow was stopped. The risk he regarded as high because it would have required a surgical incision behind the knee straight through the area where the collaterals existed which in his view were sustaining the leg. He believed the result of that would have been that the appellant would have lost his leg because it would have divided his collaterals which were the only vessels that sustained the leg in the presence of the tibial artery occlusions.
As for bypass surgery, that is surgery to bypass the occluded area, the second respondent said his view was that as the duplex scan indicated there was reconstitution of flow within the posterior tibial artery at the ankle joint the bypass would have had to have been plugged in at the ankle. His view was that this would have had the result of saving his foot but losing the calf as the surgery would have required a cutting of the collaterals which supplied blood to the calf.
The second respondent said he gave consideration to a Fogarty catheter, which is a tube with a balloon on the end which is able to be passed down an artery and inflated and used to retrieve thrombotic material. The second respondent said that a Fogarty catheter is fairly rigid and will only go down an artery and will not traverse vessels. Therefore in this situation he considered that it would be necessary to insert it into the popliteal fossa behind the knee in order to approach the smaller vessels. However, this would not have cleared the thrombotic material in the tiny branches and microvascular system. He said that is why it fails after a few hours. He also referred to the complication of arterial damage from the catheter itself.
With respect to the use of a catheter to aspirate the clot in the popliteal artery, the second respondent said that "we" have not had particularly good results with the use of the method. He referred to the large diameter of the catheter and the fact that it had similar limitations as the Fogarty catheter.
The second respondent said he also considered the use of clot dissolving treatment as opposed to anticoagulant treatment which prevents further clotting. However, he dismissed this because of the risk of "torrential haemorrhage" at the site of the operation.
The first respondent left the operating theatre at about 3.30 pm and tried to find the appellant but at that time he was undergoing the duplex scan.
At 4.00 pm an observer recorded that the colour of the appellant's leg was pink, temperature warm, movement present, sensation absent and the columns for pedal pulses and remarks are blank.
The second respondent saw the appellant for a second time after he received the results of the duplex scan at approximately 4.30 pm and again at around 6.00 pm.
During the 4.30 pm consultation the second respondent thought that there had been a slight improvement in the perfusion of the leg in that the colour was somewhat better and the pain was somewhat less.
The first respondent was present during the 4.30 pm consultation. After reviewing the written advice of the second respondent the first respondent discussed the appellant with the second respondent. The second respondent advised the first respondent that he was concerned about the appellant's leg in that the duplex scan had shown no run off but that a bypass operation in his view was contraindicated.

Notice of Contention

The learned trial Judge found that if, as I have concluded, it was negligent for the respondents to come to the view that the popliteal artery was chronically occluded and to base their treatment on that view then at the very least it was appropriate to perform an angiogram to determine the nature of the injury to the popliteal artery.
On the hearing of the appeal counsel for the respondents orally moved a notice of contention. The Court allowed the notice of contention in these terms:
"The judgment be affirmed on the grounds that:
1.the trial Judge erred in finding that the second respondent should have carried out an angiogram because it would determine the nature of the injury and assist the decision as to appropriate treatment; and
2.the trial Judge should have found on the preponderance of the expert medical evidence that an angiogram would have provided a clearer picture of blood flow in, relevantly, the arterial vessels."
I do not accept that the judgment should be affirmed on the grounds set out in the notice of contention.
After reviewing the evidence of the three vascular surgeons the learned trial Judge was of the view that the opinion of Mr Milne carried greatest weight. Her Honour considered that Mr Milne gave more cogent explanations for his opinions and had more relevant experience than Mr Lawrence‑Brown.
The learned trial Judge's conclusion was based on the evidence of Mr Milne, which her Honour accepted on this point. In his oral evidence Mr Milne gave evidence that regardless of the exact mechanism that had caused the blockage the appropriate response would have been to do an angiogram.
An angiogram is an examination of blood vessels using x‑rays. The operator inserts a catheter, or small tube, in the artery in the groin area and then injects contrast, that is, x‑ray dye, that makes the vessels visible when the x‑ray pictures are being taken. This allows the operator to determine how well the blood moves through the vessels of the leg. Mr Milne explained (AB 434) that if the angiogram showed a blockage then one would also use an angiogram to try and improve the situation. The radiologist or intervening vascular surgeon would normally put a wire down the catheter and poke at the blockage to try and get an idea of whether it was just thrombus or it was very solid and not able to be fixed. If it is a thrombus, the operator can quite easily aspirate the clot through the catheter thus improving the situation without resorting to other surgical options.
Mr Lawrence‑Brown said that an angiogram was not of any benefit if a vascular surgeon had decided not to actively intervene in any way. Mr Lawrence‑Brown considered that the second respondent acted appropriately when called in to give an opinion about the appellant's leg. He concluded that the second respondent determined that the limb was viable but that further surgery carried more risks than benefits. The learned trial Judge found that, contrary to the evidence given by the second respondent at trial, the action, or inaction, of the second respondent was based on his opinion that the popliteal artery occlusion was chronic. Mr Lawrence‑Brown did not address that situation.
Whether a medical practitioner carries out a particular form of treatment, including investigation and diagnosis, in accordance with the appropriate standard of care is a question in the resolution of which responsible and professional opinion will have an influential, often a decisive, role to play. However, that standard is not determined solely or even primarily by reference to the practice followed or supported by a responsible body of professional medical opinion. It is for the Court to adjudicate on what is the appropriate standard of care: Rogers v Whitaker (1992) 175 CLR 479; Rosenberg v Percival (2001) 205 CLR 434 per Gummow J at 453.
On the afternoon of 25 September the appellant had an acutely ischaemic leg which required urgent further investigation. An angiogram was the appropriate investigative tool. There was no good reason not to carry out an angiogram.
In cross‑examination the second respondent was asked whether he would have done an angiogram in a situation where the patient had a chronically occluded popliteal artery and a collateral circulation which had been compromised. The second respondent said that if one decides to operate, the first avenue to obtain more information is an angiogram. An angiogram gives you accurate information of how the blood flows. The second respondent said that if the angiogram showed a localised occlusion in the popliteal artery he would be looking to clear that occlusion by surgery if it was less than six hours old. The second respondent said that the injury occurred at the time of surgery and it was 30 hours after surgery when he saw the appellant. However, the development of ischaemia in the appellant's right leg occurred not at the time of surgery but on the morning of 25 September, that is within six hours of the second respondent seeing the appellant. The second respondent maintained in cross‑examination that he believed the occlusion occurred at the time of surgery. However, that does not adequately answer the point that the complete occlusion and the development of ischaemia in the right leg occurred on the morning of 25 September 1998.
In any event, the learned trial Judge found that, contrary to the evidence given by the second respondent at trial, on 25 September 1998 the second respondent believed that the occlusion was chronic and that was his reason for not carrying out any intervention or further investigation. As I have concluded, there was no proper basis for the second respondent to act, or not act, on the basis that the occlusion was chronic. In cross‑examination the second respondent said (AB 498) that the popliteal artery being chronically occluded was only a suspicion. The trial Judge found that on 25 September the second respondent acted on the basis that the occlusion was chronic. However, the evidence of the second respondent at trial that the chronic occlusion was only a suspicion is an acknowledgment that on 25 September 1998 he should not have acted, or not acted, on the basis that the occlusion was chronic because whilst he may have suspected the situation was chronic he could not properly act on that basis without further investigation.
The learned trial Judge was right to accept Mr Milne's evidence that at the very least it was appropriate to perform an angiogram to determine the nature of the injury to the popliteal artery. Her Honour also accepted that in that process the radiologist or intervening vascular surgeon would normally put a wire down the tube to poke at the blockage to try and discover whether it was just thrombus or whether it was solid and not able to be fixed. The second respondent was negligent in not carrying out the angiogram.

Responsibility of the First Respondent

At par 275 of her Honour's reasons the learned trial Judge found that once the first respondent had obtained the second respondent's opinion he was almost bound to follow the second respondent's advice with respect to vascular treatment as he was the expert. Her Honour did not accept that the first respondent could not question the second respondent's proposed treatment but was not persuaded that the first respondent's reliance upon the second respondent's advice which was not to surgically intervene was negligent.
Ground 2 of the appeal asserts that the first respondent continued to take some responsibility for the appellant's treatment, and to the extent that he did not transfer responsibility for the management of the appellant's condition to the second respondent, the learned trial Judge erred in not concluding that the first respondent, having regard to the seriousness of his patient's condition, was also negligent in not arranging an angiogram and appropriate treatment.
The first respondent should have recognised, in light of the post‑operative history, that on 25 September the appellant was suffering from a critical ischaemia which required urgent further investigation. He had overall responsibility for the care of the appellant and should have ensured that such investigation occurred.
The learned trial Judge found that there should have been further discussion between the respondents as to possible treatment to increase the appellant's chances of keeping his leg and avoiding complications of the ischaemia. The first respondent failed to consult with the second respondent and form an opinion as to the cause of the developing ischaemia in the appellant's leg or what further investigations should be carried out to enable the surgeon to form a proper opinion as to the cause of the developing ischaemia and the options for surgical intervention.
With respect to the orthopaedic surgeons who gave expert evidence, the learned trial Judge preferred the evidence of Professor Nade to that of Mr Hill. Her Honour accepted the evidence of Professor Nade in respect to the interpretation of what occurred at the relevant times, particularly post‑operatively, and as to what was or was not appropriate treatment. Her Honour considered that Professor Nade's evidence supported her view that the first respondent's reliance upon the second respondent's advice which was not to surgically intervene, was not negligent.
Professor Nade was of the opinion that the appellant's treating doctors should have made further investigations to determine the cause of the ischaemia. Professor Nade's reference to treating doctors is a reference to, or includes, the first respondent. Professor Nade said that it would have been prudent to seek an opinion from a vascular surgeon to investigate the blood supply to the appellant's leg and, if necessary to restore that blood supply. In cross‑examination Professor Nade did not accept that as an orthopaedic surgeon he would leave the decisions as to appropriate investigation to the vascular surgeon. Thus, contrary to her Honour's reasoning, Professor Nade's evidence did not support her Honour's conclusion. To the contrary, the evidence of Professor Nade is to the effect that an orthopaedic surgeon should not leave the decision as to appropriate investigation to the vascular surgeon.
In my opinion, the first respondent was negligent in failing to cause an angiogram to be carried out to investigate the occlusion to the popliteal artery in the appellant's leg.

Causation

The learned trial Judge went on to find that she was not satisfied that the second respondent's failure to perform the angiogram and intervene caused the appellant's injuries. Ground 1 of the appeal challenges this finding and asserts that the learned trial Judge should have found that if the respondents had performed an angiogram it is likely that it would have revealed the thrombus, the thrombus would have been removed, blood flow would have been reinstituted and the adverse outcome would have been prevented. Ground 5 also asserts that the learned trial Judge erred in failing to conclude that the respondents' negligence, in failing to perform an angiogram, caused the adverse outcome. Alternatively, ground 6 asserts that the learned trial Judge erred in not sufficiently explaining her finding that there was not sufficient evidence to reach the conclusion that the respondents' negligence caused the adverse outcome.
In April 2000 the appellant had a scan which showed that the popliteal artery was patent. Thus, as the learned trial Judge concluded, somehow the occlusion had dissolved. Mr Milne gave evidence that the angiogram report reinforced his impression that the arterial injury was relatively minor in terms of anatomical disruption and that this was largely a thrombotic event and therefore would be more than likely amenable to an endovascular technology to alleviate it, such as sucking the clot out at the time. Mr Milne gave evidence (at AB 482):
"With the hindsight bias that we now have with an arteriogram showing this artery's indeed still patent at this time, means that the blockage at the time of surgery was transient and this has been documented on angiography. This artery would not have reopened after chronic fibrosis occlusion, so the evidence currently available shown to me this morning there's absolutely no doubt that this is not a chronic fibrous occlusion of the popliteal artery …"
The learned trial Judge found Mr Milne to be the vascular surgeon whose opinion carried the most weight. Furthermore, his opinion on these matters was not contradicted by any other expert evidence. Mr Lawrence‑Brown agreed that the occlusion was acute and that if it was an acute occlusion you may be able to remove the acute occlusion and re‑establish flow through the existing pathway.
The learned trial Judge stated at par 298 of her reasons that she was not satisfied that the second respondent's failure to perform the angiogram and intervene caused the appellant's injuries. Her Honour elaborated upon that finding at par 299 of her reasons. Her Honour said that at the time the appellant developed ischaemia he had at least a 50 per cent chance of losing his leg whether or not there was surgical intervention. The conservative treatment has resulted in him keeping his leg. There is no doubt he has suffered damage to his leg as a result of the fasciotomy not healing. Her Honour said that there was however insufficient evidence to prove that those injuries would have been avoided if the second respondent had attempted surgical intervention sometime after the duplex scan result was obtained. In my view, her Honour was not there considering the procedure described by Mr Milne of poking a wire down the catheter during the course of an angiogram to remove the thrombus and restore the blood flow.
Her Honour went on to say that revascularising the leg would have led to a greater chance of compartment syndrome occurring through reperfusion. That is not to deny that the compartment syndrome which in fact occurred and caused damage to the appellant's leg would have been avoided. There was evidence that revascularising the leg gives rise to the risk of compartment syndrome occurring through reperfusion. If blood flow had been restored during the angiogram then the doctors attending on the appellant would have been obliged to monitor his right leg carefully for signs of compartment syndrome developing. However, the evidence stopped short of establishing that if the appellant's leg was revascularised it was more likely than not that a compartment syndrome would have occurred and would have led to the damage which the appellant suffered.
Her Honour further found that if, as she accepted, the leg was gradually becoming ischaemic throughout 24 September and was ischaemic at around 10.30 am on 25 September, the damage to the appellant's muscle had in all likelihood occurred by the time the second respondent was in a position to revascularise the leg.
Her Honour found that when the first respondent visited the appellant at approximately 7.00 am on the morning of 25 September and examined him there was no cause for concern about the appellant's leg. The symptoms of ischaemia developed during the course of the morning of 25 September. The second respondent gave evidence that muscle will only survive for six hours once the blood flow is stopped. Her Honour made no finding as to when the blood flow stopped nor did her Honour state that she accepted the evidence of the second respondent that muscle will only survive for six hours once the blood flow is stopped. Mr Milne, the vascular surgeon whose evidence her Honour preferred, was asked in cross‑examination whether he accepted the period of six to eight hours as a period associated with irreparable damage from the onset of critical ischaemia. Mr Milne replied (AB 468) that one cannot put a time frame on it and you often get a tremendous degree of variation. There is a variation from one patient to another. Mr Milne opined that the muscle was irreversibly damaged sometime prior to the fasciotomy performed at 3.00 am on 26 September but it was difficult to say when it started and there is not enough material to say when some of the tissue in the leg became irreversibly damaged rather than reversibly damaged. I conclude that there is no evidence from which it could be inferred that the damage to the appellant's muscle had in all likelihood occurred by the time the second respondent was in a position to revascularise the leg.
Further, her Honour accepted that any of the techniques that were available to the second respondent to use in an attempt to revascularise the leg carried with them their own risks of serious damage to, and even loss of, the leg. In my view, her Honour was there referring to techniques other than the removal of the thrombus in the course of an angiogram in the manner I have described. If so, it is not relevant that other procedures carried with them their own risks of serious damage. If her Honour's reference to any of the techniques that were available to the second respondent to use in an attempt to revascularise the leg includes the removal of the thrombus in the course of the angiogram in the manner I have described, then that finding cannot be sustained. There is no evidence that that procedure carried any risk of injury.
For those reasons, the learned trial Judge erred in finding that the second respondent's failure to perform the angiogram did not cause the appellant's injuries. The evidence accepted by the learned trial Judge established that the likely cause of the occlusion was a thrombus and it could have been removed by endovascular procedure. In my opinion her Honour should have so found.
The respondents should have carried out, or suggested, an angiogram. If an angiogram had been carried out then, on the balance of probabilities, the thrombus would have been removed, the blood flow to the leg would have been restored and the appellant's subsequent injuries consequential upon the development of compartment syndrome and the subsequent fasciotomy would have been averted.
For those reasons, the appellant is entitled to succeed against each of the respondents.

Ground 6

Ground 6 is that, in the alternative to grounds 1 to 5, the learned trial Judge erred in law and fact in not sufficiently explaining her finding that there was not sufficient evidence to reach the conclusion that the respondents' negligence caused the adverse outcome. In considering grounds 1 to 5, I have concluded that the learned trial Judge erred in failing to find that the respondents' negligence caused the adverse outcome and the appellant is entitled to succeed in this appeal against both respondents. In those circumstances it is not necessary to further consider ground 6.

Ground 7

Ground 7 is that the learned trial Judge erred in law and fact in not finding the first respondent was negligent in offering the total knee replacement surgery to the appellant.
The learned trial Judge considered this allegation together with the allegation that the first respondent failed to advise the appellant that, by reason of his right leg's compromised circulation, he was at greater risk of developing compartment syndrome than a person of similar age otherwise would be. Her Honour found that the allegation that the first respondent failed to advise the appellant that he was not a suitable candidate for knee replacement surgery by reason of his right leg's compromised circulation failed because the appellant had not established that he was not a suitable candidate for arthroplasty. Her Honour's finding was based upon the evidence of Mr Milne. Mr Milne considered that if a vascular assessment had been undertaken and disclosed the appellant's pre‑existing large vessel vascular disease, the advice would have been that it was reasonable to proceed with surgery as long as peripheral pulses were present. Her Honour accepted that those pulses were present and were palpated by the first respondent. Her Honour concluded that Mr Milne's opinion made it impossible for the appellant to succeed on his case with respect to the failure to obtain a vascular opinion and with respect to the appellant being unsuitable for arthroplasty. This is because those claims are based on a conclusion that if the vascular opinion had been obtained it would have said that the appellant was not a suitable candidate for arthroplasty and he should not have therefore been offered the surgery. Her Honour considered that Mr Milne's opinion, which she accepted, negated that hypothesis.

It was open to the learned trial Judge to accept the opinion of Mr Milne. Her Honour made no error. This ground of appeal fails.

Ground 8

Appeal ground 8 is that the award of damages made by the learned trial Judge in relation to the effects of the negligent administration of gentamicin was inadequate and below the range of a sound discretionary judgment.
Senior counsel for the appellant, Mr Zelestis QC, submitted that if the appellant succeeded in his appeal against the findings of the learned trial Judge that the first respondent was not negligent and the second respondent was not negligent in his post‑operative treatment of the appellant then it was probably not necessary to deal with the appellant's appeal against the learned trial Judge's award of damages in respect of the negligent administration of gentamicin by the second respondent because damages at large should go back to be assessed because:
"One wouldn't try to compartmentalise the damages from the gentamicin issue to the other, and secondly, … the case ought be remitted to the Supreme Court pursuant to s76 of the District Court Act … and remitted to [the learned trial Judge] on the basis that there would then only be a need for limited evidence to update the position".
Mr Zelestis QC submitted that it was to be expected that the parties would not re‑litigate in its entirety the question of damages, so there would be efficiency and cost savings and he did not understand that to be an issue for the respondents. Senior counsel for the respondents, Mr Gilmour QC, did not contradict that statement.
Notwithstanding the practical convenience of the course proposed by Mr Zelestis, the court should determine the appellant's appeal against the award of damages and the respondent's cross appeal. The court should only set aside the award of damages if it is satisfied that the learned trial Judge has made an error in the assessment of damages. Accordingly, I will proceed to consider ground 8 of the appeal, that is the appellant's appeal against the trial Judge's award of damages.

Cross Appeal

The respondents have cross appealed against the award of damages against the second respondent in relation to the gentamicin side effects. It is convenient to consider the cross appeal and the issues raised by ground 8 of the appeal together.

Trial Judge's Assessment of Damages

The learned trial Judge observed that whilst the appellant gave evidence of some of his disabilities arising from the antibiotic administration, in many respects when detailing the difficulties he had in his daily life he did not differentiate between problems caused by the effects of the arthroplasty and those caused by the antibiotic administration. That made it difficult to assess his damages for the antibiotic administration.
The learned trial Judge properly noted that the appellant's damages for antibiotic related injuries must be assessed in light of his pre‑existing disabilities and injuries. Her Honour accepted that as a consequence of the arthroplasty and its complications the appellant had and continued to suffer from loss of muscle in his right leg, foot drop, recurrent infection in his leg and lymphedema.
With respect to loss of hearing the learned trial Judge accepted that the appellant had suffered a loss of hearing in his left ear that is permanent but found that it was not a significant disability. The appellant gave evidence that he had a number of vestibular dysfunction symptoms including nausea, dizziness and ringing in his ears. He said that he had permanent loss of balance but his body has compensated somewhat for that by the use of his eyes. He said it was difficult to get around and he was very clumsy and quite slow. He had to be very careful when driving a motor vehicle. He said that if he was subjected to a lot of stimuli he could get disoriented quite easily and quickly. The learned trial Judge accepted the appellant's evidence in relation to the nature and effect of his vestibular injuries. However, her Honour considered that there was an issue as to the extent to which some of the appellant's problems are related to his landmine injuries and the arthroplasty and its complications as opposed to the antibiotic related injuries. Her Honour found that most of the loss claimed is related to that part of the appellant's claim for which the second respondent was not liable, that is the claim other than in respect of damages resulting from the negligent administration of gentamicin.
Her Honour found that the appellant had suffered past loss of earnings and a diminution in his earning capacity as well as being entitled to damages for past gratuitous and paid services and future gratuitous and paid services and damages under other heads as well as general damages. Her Honour assessed damages as follows:
Past loss of earnings   $7,751
Interest thereon   $465
Future loss of earnings  $13,500
Past gratuitous and paid services              $20,465
Interest thereon   $1,228
Future gratuitous and paid services          $26,437
Special appliances   $2,000
Home modifications   $10,000
Rest and recreational needs   $10,000
General damages   $40,000
Total  $131,846
The appellant challenges the award under various heads of damage. First, the appellant submits that the award of $40,000 for pain and suffering and loss of amenities was inadequate for loss of fundamental senses especially in the context of the appellant's existing disability in the lower limbs. Secondly, the appellant submitted that an award of $21,251 for loss of earning capacity (past and future) caused by the gentamicin disabilities is manifestly inadequate. Thirdly, the appellant submitted that the awards for paid and gratuitous services (past and future), special appliances, home modifications, future medical treatment and other needs are inadequate. Finally, the appellant submitted that the overall award of $131,846 for the effects of the gentamicin ototoxicity is manifestly inadequate.
The respondents challenge the damages awarded under the paid and gratuitous services, past and future economic loss, home modifications and rest and recreational needs heads of damages.

Pain and Suffering

Junior counsel for the appellant, Mr Lampropoulos, submitted that the main problem with the gentamicin effects is the appellant's loss of sense of balance. The appellant has a prosthetic left leg and stiffness and foot drop in the right leg. Physical balance is difficult for him. The effects of any loss of the sense of balance are therefore magnified. Counsel submitted that the loss of the sense of balance in a person with the appellant's disabilities is far more magnified than someone who has normal lower limbs. The appellant has developed symptoms of giddiness, vertigo, imbalance, nausea, hearing loss and tinnitus as a result of the gentamicin induced ototoxicity. It is more difficult for the appellant to walk. The condition affects his ability to drive. It affects his ability to negotiate steps. These difficulties affect all aspects of daily life.
An appellate court cannot, of course, properly interfere with an award of damages merely because it would itself have awarded more or less: Planet Fisheries Pty Ltd v La Rosa (1968) 119 CLR 118 at 124. I am not satisfied that the learned trial Judge acted upon any wrong principle of law or allowed extraneous or irrelevant matters to guide or affect her discretion, or failed to give weight to matters relevant to the award of general damages. The trial Judge assessed general damages by reference to all relevant evidence, in particular that of substantial impairment of the appellant's sense of balance. The award of $40,000 for general damages is not so unreasonable or plainly unjust that this Court should infer that an error has been made. In short, the appellant has not established that the learned trial Judge erred in the award for general damages.

Loss of Earnings and Earning Capacity

The learned trial Judge found that the antibiotic caused injuries had diminished the appellant's earning capacity. It was the appellant's case that the arthroplasty related injuries caused him to give up his permanent employment with the Department of Commerce and Trade on 25 August 2000. However, he continued to work from home by doing part time consultancy work through a partnership with his wife. The appellant had incurred his antibiotic related injuries by the beginning of September 2000. The learned trial Judge found that the appellant retained some earning capacity after the arthroplasty and retained some to the date of trial. Nonetheless that earning capacity had been reduced since the appellant received his antibiotic related injuries. Her Honour found that his use of crutches at all times and his vestibulopathy had reduced his earning capacity, for example, by reducing his speed, mobility and concentration. Her Honour found that those disabilities had resulted in a further 20 per cent diminution in the appellant's earning capacity which had already been greatly reduced after the arthroplasty. Her Honour assessed the amount of the loss of earnings by saying that were it not for the appellant's injury in each year since incurring his antibiotic injuries he would have been able to earn 20 per cent more than he did. For the year ending June 2001 her Honour made a further adjustment to take into account that the appellant only had the injuries for 83 per cent of the year.
The respondents challenge the award for past and future economic loss. They submit that there was no or no sufficient evidence that such loss was attributable to the effects of the administration of gentamicin.
The respondents refer to the evidence of Dr Merrick, a rehabilitation specialist, called on behalf of the appellant. It is submitted that Dr Merrick attributed the appellant's reduction in earning capacity, in substance, to his deterioration in ambulatory function due to complications following the total knee replacement and to his progressive peripheral vascular disease including lymphedema, that Dr Merrick did not attribute any loss of earning capacity to the effects of the gentamicin, and that to the extent that he referred to the effect of gentamicin, Dr Merrick stated that the appellant had made an adjustment to his vertiginous problems such that he was able to drive a car.
The learned trial Judge found that the appellant's earning capacity had been reduced since he received his antibiotic injuries. Her Honour found that the appellant's use of crutches at all times and his vestibuloplasty had reduced his earning capacity, for example, by reducing his speed, mobility and concentration. It was open to her Honour to make that finding and her Honour made no error in doing so.
The appellant submits that the trial Judge erred in using the appellant's income in the year ending June 2001 as the basis of the calculation for past loss of earnings because that year was affected by the gentamicin disabilities. I am not persuaded that to do so involved any error.
The learned trial Judge accepted that the appellant's compensable injuries will continue to be productive of economic loss for the rest of his working life. On the basis her Honour had earlier explained she assessed the appellant's loss of earning capacity to be approximately $2,600 for the year ending 30 June 2001 or $50 per week. Her Honour adopted that figure as an appropriate figure to use for purpose of calculating the plaintiff's future economic loss. Her Honour calculated future loss of earnings on the basis that the appellant would continue working until the age of 65 years and 4 months. Her Honour did so taking into account the appellant's work history and the fact that he was working from home. The appellant has not demonstrated that her Honour made any error in assessing future loss of earnings.

Paid and Gratuitous Services

The respondents submit that the appellant's need for paid and gratuitous serves was a result of mobility impairment which had been caused and which would continue to deteriorate as a result of his landmine injuries, the progression of his vascular disease and complications from the arthroplasty. The respondent submitted that there was no or no sufficient evidence to warrant awarding any damages under this head of claim.
The learned trial Judge found that the antibiotic caused injuries had resulted in some of the gratuitous services being required for the appellant. Her Honour was of the opinion that the award under this head should be a percentage of the total claimed. Her Honour concluded that a reasonable figure was 30 per cent of what was claimed bearing in mind that all the tasks covered by the gratuitous services are matters that are affected by the appellant's vestibuloplasty. There was evidence before her Honour from which her Honour could conclude that some of the appellant's need for gratuitous and paid services subsequent to September 2000 arose from or was a result of the antibiotic injuries. I am not persuaded that her Honour made any error in assessing that head of damages. I note that her Honour specifically took into account the appellant's severe arterial disease which in the future may well require him to need those services regardless of his compensable injuries and applied a discount of 50 per cent on that account.
The appellant also challenges the award for paid and gratuitous services (past and future), special appliances, home modifications, future medical treatment and other needs. The learned trial Judge made an award of damages for each of those heads of damage. The evidence made it very difficult for her Honour to distinguish the extent to which the appellant's past and future need for services, appliances and other needs arose from the gentamicin injuries rather than his landmine injuries and the arthroplasty. I am not persuaded that her Honour made any error in her approach to assessing those heads of damage. Nor am I persuaded that the amounts awarded by her Honour under those heads are so unreasonable or plainly unjust that the court should infer that an error has been made.
The appellant claimed $305,500 for external, internal and other costs related to home modifications. The learned trial Judge found that the need for these alterations was a consequence of the appellant's landmine injuries or the arthroplasty complications. However, the vestibuloplasty caused the appellant to need additional balustrades and handrails throughout his home and her Honour awarded a global sum of $10,000 for such alterations.
The respondents submit that there was no, or no sufficient, evidence that further balustrades were required as a result of the effects of gentamicin. Her Honour's finding was based upon the evidence of the effect of the gentamicin injuries upon the appellant including his use of crutches and loss of sense of balance. It was open to her Honour to make the finding and assessment that she did.
The respondents challenge the learned trial Judge's award of damages for rest and recreational needs. The appellant had claimed for increased costs associated with holiday travel and accommodation in Australia and overseas. The claim principally related to the cost of a travelling companion, business as opposed to economy airfares, modified accommodation and vehicles. Her Honour found that almost all of these costs relate to the appellant's needs caused by his landmine injuries or arthroplasty complications. However, when travelling, the appellant would need some extra facilities because of his vestibular problems. Her Honour awarded a global award of $10,000 under this head. I am not satisfied that her Honour made any error in doing so.

The Overall Award

Finally, the appellant submits that the overall award of $131,846 for the effects of the antibiotic injuries is manifestly inadequate. I am not persuaded that the overall award of damages is outside of the bounds of a reasonable exercise of discretion, that is the result is not so unreasonable or plainly unjust that the court should infer that an error has been made.
For the reasons stated, neither the appeal against damages nor the cross appeal is made out.

Disposition of Appeal and Cross Appeal

I would allow appeal FUL 111 of 2003 insofar as the appellant appeals on the issues of liability, dismiss the appellant's appeal from the assessment of damages in relation to the negligent administration of gentamicin and dismiss the second respondent's cross appeal.
I would hear further from the parties in relation to the submission of senior counsel for the appellant that the matter ought be remitted to the Supreme Court pursuant to s 76 of the District Court Act and remitted to her Honour the trial Judge as a Judge of the Supreme Court.
I would dismiss appeal FUL 12 of 2004.