Massih v Electricity Networks Corporation t/as Western Power - [2016] WADC 146

JURISDICTION : DISTRICT COURT OF WESTERN AUSTRALIA
IN CIVIL

LOCATION: PERTH

CITATION: MASSIH -v- ELECTRICITY NETWORKS CORPORATION t/as WESTERN POWER [2016] WADC 146

CORAM: SCHOOMBEE DCJ

HEARD: 5 SEPTEMBER 2016

DELIVERED : 4 OCTOBER 2016

FILE NO/S: APP 32 of 2016

BETWEEN: TONY MASSIH
Appellant
AND
ELECTRICITY NETWORKS CORPORATION t/as WESTERN POWER
Respondent

ON APPEAL FROM:
Jurisdiction              :  WORKERS' COMPENSATION ARBITRATION SERVICE (WA)
Coram  :ARBITRATOR NUNN
File No  :A 27386 of 2015

Catchwords:

Workers' compensation - Appeal - Error of law - Worker's burden of proof - Briginshaw v Briginshaw not applicable - Employer's evidentiary burden - Causal connection between injury and incapacity - Preexisting condition - Reasonable expenses for surgical treatment

Legislation:

Workers' Compensation and Injury Management Act 1981 (WA) s 5(1), s 18, sch 1, cl 17

Result:

Leave to appeal granted
Appeal upheld

Representation:

Counsel:

Appellant: Mr M Lourey
Respondent: Mr G Nutt

Solicitors:

Appellant: Chapmans
Respondent: Jarman McKenna

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

Ardela Holdings Pty Ltd v Hateley [No 2] [2016] WASCA 141
Australian Broadcasting Tribunal v Bond (1990) 170 CLR 321
BHP Billiton Iron Ore Pty Ltd v Brady [2008] WASCA 250
Briginshaw v Briginshaw (1938) 60 CLR 336
CEPU v ACCC (2007) 162 FCR 466
Cole v P & O Ports Ltd [2002] WASCA 157
Kooragang Cement Pty Ltd v Bates (1994) 35 NSWLR 452
Leggett v Argyle Diamond Mines Pty Ltd [2000] WASCA 182
March v E & MH Stramare Pty Ltd (1991) 171 CLR 506
Mayne Nickless Ltd t/a Wards Express v Mayne (Unreported, WASCA, Library No 960736, 19 December 1996)
Medlin v State Government Insurance Commission (1995) 182 CLR 1
Napier v BHP Billiton (Worsley Alumina) Pty Ltd [2015] WASCA 230
Pacific Industrial Co v Jakovljevic [2008] WASCA 60
Purkess v Crittenden (1965) 114 CLR 164
Secretary to the Department of Premier and Cabinet v Hulls [1999] 3 VR 331
Watts v Rake (1960) 108 CLR 158

SCHOOMBEE DCJ: This matter concerns an appeal brought under the Workers' Compensation and Injury Management Act 1981 (WA) (the Act) by Mr Tony Massih, the worker, against a decision by the Workers' Compensation Arbitration Service delivered on 1 April 2016 pursuant to which the arbitrator refused an application by Mr Massih that Western Power, his employer, pay the costs of a hip replacement operation and related medical expenses. Mr Massih had submitted that his left hip problems and related symptoms were the result of an injury caused by an accident at work.

Background facts

Mr Massih worked for Western Power for 26 years, initially as a labourer and cable layer and later as a cable jointer. On 14 April 2014 Mr Massih was sent with others in a crew to repair a damaged high voltage cable at Western Power's Joondalup substation. On entering a dark room the floor, which was damaged by white ants, gave way and Mr Massih's right leg fell through the floor with his left leg remaining in a twisted position on top of the floor boards. He tried to push his right leg onto the cable cleats underneath the floor, but they also crumbled. Mr Massih had to be pulled out by the other crew members. He felt immediate pain and was unable to stand or walk unassisted.
Mr Massih saw his then general practitioner, Dr Andrew Fairhurst, and initially complained of pain in the neck, lower back and left knee. Dr Fairhurst referred him to Professor Riaz Khan, an orthopaedic surgeon. Professor Khan performed an arthroscopy of the left knee on 1 May 2014 and reported to Dr Fairhurst that he had repaired a tear of the medial meniscus and that the rest of Mr Massih's left knee was in excellent order.
On 17 June 2014 Professor Khan reported to Dr Fairhurst that Mr Massih was still on crutches and continued to have significant pain in the knee. Professor Khan described it as an 'exaggerated pain response'. He expressed the view to Dr Fairhurst that the ongoing pain was not likely to be from the surgery and wrote 'I wonder whether this actually happened from the time of the injury rather than from surgery'. Professor Khan referred Mr Massih for a steroid injection into the knee and told him to mobilise without crutches.
On 14 July Professor Khan wrote to Mr Massih's new general practitioner, Dr Nat Wright. He reported that Mr Massih was still having trouble on the lateral side of his left knee and said he found this 'curious' as that area had appeared to be pristine at the time of surgery. A repeat MRI scan in July 2014 showed that there were no obvious problems with the left knee. Professor Khan reported on 28 July 2014 that Mr Massih was about to spend 'a couple' of months in Lebanon on holiday.
On 16 December 2014 Mr Massih's physiotherapist reported that Mr Massih was receiving ongoing treatment for his neck and lower back pain and that his hips were stiff and greater mobility was required to ease his pain. The physiotherapist again reported on 9 January 2015 that Mr Massih was still experiencing pain on a daily basis, was unable to get through his normal daily tasks without aggravating his symptoms and had problems standing to water his garden or wash dishes for more than 10 minutes at a time. The report by the physiotherapist referred to posture problems, lack of cervical mobility and that hip mobility, particularly flexion, was limited by pain.
The progress notes from Dr Wright's consultations with Mr Massih during the period from 8 October 2014 to 4 February 2015 reported ongoing issues with neck and back pain, but also left knee pain. On 19 January 2015 there is an entry that Mr Massih reported electric shock sensations in the left lower limb during the past month, as well as experiencing pins and needles. Nevertheless, Dr Wright noted on various occasions that Mr Massih was keen to get back to work and it seems that Mr Massih returned to light duties in early 2015.
On 4 February 2015 Dr Wright recorded in his progress notes that Mr Massih had told him that his leg had given way that morning at work when he had walked over a speed bump and he had fallen onto his left side. He hurt his left knee and left wrist. A further note made on the same date states that Mr Massih was 'just able to walk, in a wheelchair' and had a 'new injury'.
On 6 February the progress notes recorded that Mr Massih's left knee and left leg were painful. Between 13 February and 10 March, there are references in Dr Wright's progress notes to a further six occasions on which Mr Massih's knee gave way. A progress note on 10 March 2015 stated that Mr Massih had ongoing issues with his left knee but went to work despite having a certificate declaring him not fit for work. A number of progress notes in February and March recorded that Mr Massih was keen to get back to work, was concerned about losing his job and wanted to resume light duties.
The progress note of 10 March also stated: 'injury from Feb 15 now merged with injury from April 14, on advice of insurance company'.
A report from Professor Khan to Dr Wright, dated 9 March 2015, stated that it was difficult to say 'what was going on' with Mr Massih as he still reported pain on the medial side of the knee and it giving way occasionally whereas the latest MRI showed no significant abnormality in the knee. Professor Khan noted some loss of internal rotation of the hip, but that it was symmetrical and not painful.
Dr Wright's progress note from 17 March 2015 stated that he had a discussion with Professor Khan who agreed that there was no clear cause for the knee giving way and that the likely cause might be Mr Massih's deconditioning. On 22 April 2015 Dr Wright recorded in his notes that Mr Massih's knee was giving way less often.
On 5 May 2015 Professor Khan reported to Dr Wright that Mr Massih had described pain in the left groin region and that he had complete loss of internal rotation of the left hip. Professor Khan expressed the concern that the symptoms in the knee might be emanating from the arthritic hip. He noted that he had referred Mr Massih for a steroid injection into the left hip as well as x-rays of the hip.
On 8 May 2015 Dr Wright's notes recorded ongoing neck, back and knee issues. He stated that Mr Massih was scheduled for a CT guided cortisone injection into the left hip and made the note '? cause of hip/knee giving way'. On 29 May 2015 Dr Wright recorded that the cortisone injection into the hip had not helped.
On 9 June 2015 Professor Khan wrote to Dr Wright, advising that Mr Massih had been reviewed after an MRI scan which justified his pain in the neck, lower spine and left hip. The MRI of the left hip demonstrated full thickness cartilage loss with secondary bone oedema and Professor Khan reported that this would 'most certainly account for his groin pain which he rates at 8 out of 10'.
It therefore seems that it was only after the MRI in June 2015 that Mr Massih was diagnosed with osteoarthritis in the left hip and Professor Khan came to the conclusion that this was likely to have been pre‑existing, prior to the work accident. He stated the following in his letter of 9 June 2015:
Importantly none of the above pains were present prior to the accident in April 2014. Tony most likely needs to have his left hip replaced. … My take on the situation is that he may have had osteoarthritis prior to the accident but this was asymptomatic and therefore would be a reasonable likelihood that he would be able to continue his working life through to age of sixty five and retire. This accident has therefore brought about premature end to his working life.
On 11 August 2015 Professor Khan reported to Dr Wright that on review of Mr Massih his left hip was the main problem with pain radiating to the left knee. In addition, he also had lower back pain on the right side which presumably came from facet joint osteoarthritis at L5 and S1. Professor Khan noted that the cervical spine was also causing Mr Massih trouble, but to a lesser degree. Professor Khan expressed the opinion that Mr Massih would not be able to go back to work without a left hip replacement. Professor Khan added that seeing that Mr Massih had no symptoms prior to his fall on 13 April 2014, 'it would be very reasonable in the court of law to attribute them to his accident'.
A hip replacement operation was booked for Mr Massih for 9 September 2015. However, it did not proceed because the insurer of Western Power declined to fund the surgery. Mr Massih then applied for a ruling by the arbitrator that his employer was liable to pay for the surgery and related expenses.
The arbitrator found that there was insufficient evidence to prove that the hip problems and related symptoms arose from an injury caused at the time of the work accident. The arbitrator essentially came to that conclusion because Mr Massih had only started to experience pain emanating from the groin area almost a year after the work accident. Before that Mr Massih had only complained about pain in the left knee and the knee giving way when walking.
Although the arbitrator identified at [95] that one of the issues before him was whether Mr Massih's pre‑existing osteoarthritis in his left hip had been rendered symptomatic by the work accident, he did not come to any specific conclusion in that regard.
The arbitrator further considered whether Mr Massih's incapacity resulted from a subsequent injury to his hip when he fell down after his left knee gave way, even though the arbitrator acknowledged that this argument had not been relied upon by Mr Massih [85]. The arbitrator came to the conclusion that there was also insufficient evidence to prove that the hip problems had resulted from the later injury.

Grounds of appeal

Mr Massih filed an appeal against the decision of the arbitrator on 29 April 2016. The four grounds of appeal may be summarised as follows:
1.The learned arbitrator miscomprehended the evidence presented by Mr Massih in that he failed to consider whether the injury to the left hip occurred on 15 April 2014 during the accident at work. In particular, the arbitrator failed to refer to the statement by Mr Massih in which he said that his left leg remained up on the floor in a twisted position. Further, the arbitrator concluded that he could not consider the hip problems as part of the injury received on 15 April 2014, as the First Medical Certificate, Form 2B had not referred to any hip injury, but had only described the injury received as a 'twisting of knee upper & leg (left), slight abrasion'.
2.The learned arbitrator incorrectly required Mr Massih to prove his case on a balance of probabilities to the higher standard of satisfaction applied in Briginshaw v Briginshaw.
3.The learned arbitrator should have applied the but for test in determining whether Mr Massih's hip problems were caused by an injury received during the accident at work.
4.The learned arbitrator took into account irrelevant considerations when he considered whether the hip replacement surgery was a reasonable expense pursuant to cl 17 of sch 1 of the Act in that he took into account whether all other treatment options had been exhausted and whether the proposed surgery would allow Mr Massih to return to work despite his other injuries.

Leave to appeal

Pursuant to s 247 of the Act leave to appeal from this court is required. The District Court is not to grant leave unless a question of law is involved and the amount in issue meets a certain threshold. There is no dispute between the parties that the threshold has been met.
Counsel for Mr Massih submitted that the arbitrator had committed an error of law by requiring Mr Massih to prove his case, not simply on a balance of probabilities, but to the higher level of satisfaction discussed in Briginshaw v Briginshaw (1938) 60 CLR 336, 360 – 363. In that case Dixon J held that in order to be satisfied on a balance of probabilities of a particular matter a fact‑finder had to feel an actual persuasion of the existence of the facts and a mere mechanical comparison of probabilities independent of any belief in its reality would not be enough. However, the degree of satisfaction was dependent on the nature of the facts in dispute and the gravity of the consequences flowing from the finding. Where the alleged facts involved 'grave moral delinquency', such as where the committal of fraud, a crime (in civil proceedings) or adultery was alleged, the fact‑finder was entitled to require a higher standard of exactness of proof in order to be satisfied on a balance of probabilities. Where such serious matters were involved reasonable satisfaction should not be produced by 'inexact proofs, indefinite testimony, or indirect inferences'.
The Briginshaw v Briginshaw test has been applied in respect of allegations which could give rise to grave consequences such as that a crime was committed, see for example, Ardela Holdings Pty Ltd v Hateley [No 2] [2016] WASCA 141 [33], [55], [57], or that a person contravened provisions of the Trade Practices Act 1974 (Cth) which could result in significant penalties, see for example, CEPU v ACCC (2007) 162 FCR 466 [29] ‑ [37].
Counsel for Mr Massih submitted that the issues in dispute in this matter did not involve any serious allegations of 'moral delinquency' and did not require any higher level of exactness of proof or satisfaction than would apply in any other case decided in the workers' compensation jurisdiction. Counsel for Mr Massih submitted that the usual test to prove a matter in this jurisdiction was the civil standard of 'on a balance of probabilities'.
It is apparent that many cases decided in the workers' compensation jurisdiction have proceeded on the basis that the worker has a burden to prove his claim on the balance of probabilities, see for example Mayne Nickless Ltd t/a Wards Express v Mayne (Unreported, WASCA, Library No 960736, 19 December 1996), 19. This is even though s 188 of the Act provides that an arbitrator is not bound by the rules of evidence and is to act according to equity, good conscience and the substantial merits of the case without regard to technicalities and legal forms. It is certainly not appropriate to apply the Briginshaw v Briginshaw standard of proof in the workers compensation jurisdiction.
I accept that if the arbitrator applied a wrong standard of proof that would constitute an error of law. In order to be granted leave an appellant does not have to establish that an error of law was indeed made by the arbitrator. All that the appellant has to show is that there is a real or significant argument to be put which involves a question of law: Secretary to the Department of Premier and Cabinet v Hulls [1999] 3 VR 331 [10]. However, a decision does not involve a question of law unless the error is material to the decision: Australian Broadcasting Tribunal v Bond (1990) 170 CLR 321, 333. An error of mixed law and fact is also an error of law: BHP Billiton Iron Ore Pty Ltd v Brady [2008] WASCA 250 [3].
I accept that Mr Massih has established that this appeal involves an error of law, or at least an error of mixed law and fact, in that it is alleged that the arbitrator applied the wrong standard of proof. If the arbitrator applied the wrong standard of proof, that would be material to his decision. Accordingly, I grant leave to Mr Massih to bring this appeal to the District Court.
Once a question of law is involved, the whole decision appealed from is open to review: Pacific Industrial Co v Jakovljevic [2008] WASCA 60 [18]. This court must undertake a 'real review' of the application before the arbitrator, but is limited to the materials before the arbitrator. It is not a hearing de novo. Before this court may disturb the arbitrator's decision the appellant must establish a proper basis for doing so, in other words that the arbitrator made some error, either of fact, law or logic: Pacific Industrial Co v Jakovljevic [20], [26].

Ground 1 – whether the arbitrator miscomprehended the evidence and thus failed to consider whether the hip injury was caused by the work accident

Counsel for Mr Massih submitted that the learned arbitrator had 'miscomprehended' the evidence presented by Mr Massih in that he failed to consider whether the injury to the left hip occurred on 15 April 2014 during the accident at work.
Counsel for Mr Massih submitted at the hearing before the arbitrator, as well as on appeal, that Mr Massih received a hip injury during the work accident, which was misdiagnosed initially. However, the argument was also put in terms that Mr Massih's pre‑existing osteoarthritis in his left hip was rendered symptomatic by the work accident. Strictly speaking, on the facts of this case, the enquiry should have focused on whether the work accident caused a significant aggravation of the pre‑existing osteoarthritis in the hip, rather than whether a hip injury was caused during the accident.
Such an enquiry is also in line with the definition of 'injury' in s 5 of the Act, read together with s 18 which provides that if an injury of a worker occurs, the employer shall be liable to pay compensation in accordance with sch 1. The definition of 'injury' in s 5 is as follows:
injury means —
(a)a personal injury by accident arising out of or in the course of the employment, or whilst the worker is acting under the employer's instructions; or
(b)a disease because of which an injury occurs under section 32 or 33; or
(c)a disease contracted by a worker in the course of his employment at or away from his place of employment and to which the employment was a contributing factor and contributed to a significant degree; or
(d)the recurrence, aggravation, or acceleration of any pre‑existing disease where the employment was a contributing factor to that recurrence, aggravation, or acceleration and contributed to a significant degree; or
(e)a loss of function that occurs in the circumstances mentioned in section 49,
but does not include a disease caused by stress if the stress wholly or predominantly arises from a matter mentioned in subsection (4) unless the matter is mentioned in paragraph (a) or (b) of that subsection and is unreasonable and harsh on the part of the employer.

Professor Khan expressed the opinion that Mr Massih was suffering from osteoarthritis in the left hip and that it was not unreasonable to say that the work accident was at least partially responsible for bringing about the hip symptoms and consequently, the requirement for a hip replacement operation.
It therefore seems that the definition of 'injury' in subsection (d) is more appropriate than that in subsection (a), although it could be argued that the definition in subsection (d) is only intended to cover a situation where a worker suffered an aggravation of a pre‑existing condition by reason of repeated exposure to the cause of aggravation at his or her place of employment and that subsection (a) is intended to deal with a situation where an aggravation occurs during an accident at work.
For purposes of this case, it does not matter much whether the question was posed as 'was a hip injury caused by the work accident, in other words, was the pre‑existing arthritic hip injured which then produced symptoms?' or whether it was described as 'did the accident cause a significant aggravation of the pre‑existing osteoarthritis?' The only difference would be that under subsection (d) there needs to be a contribution to a 'significant degree', whereas subsection (a) does not specify the test of causation and the usual test in tort is whether the accident made a material contribution to the injury. On the facts of this case it would not have made any difference whether a significant contribution or a material contribution had to be proven. It was common cause that the pre‑existing osteoarthritis was totally asymptomatic before the work accident and that Mr Massih suffered from considerable pain by August 2015. Accordingly, any proof that the work accident caused the pre‑existing osteoarthritis to become symptomatic would have been proof that the pre‑existing condition was aggravated to a significant degree.
The arbitrator correctly identified at [11] the relevant question as being whether the previously asymptomatic degenerative condition of Mr Massih's hip was rendered symptomatic by the work accident and at [22] described the relevant question as whether the work accident made a material contribution to causing the hip problems and the need for a hip replacement. I am of the view that not much turns on the fact that these tests were formulated slightly differently. At the beginning of his decision, the arbitrator correctly identified the relevant issue.
However, after having analysed the evidence before him, the arbitrator lost focus on the question whether the hip problems were caused by an injury during the work accident or, put differently, whether the pre‑existing osteoarthritis became symptomatic because of the work accident, and instead investigated whether the pain in the hip could have been caused by Mr Massih's fall in February 2015. At [85] the arbitrator noted that Mr Massih had not specifically submitted that his symptomatology of the hip had resulted from the fall in February 2015 and that the fall had been caused by the knee problems which resulted from the work injury. Although the arbitrator acknowledged that Mr Massih had not presented such an argument, he then proceeded to consider the merits of that argument on the basis that an arbitrator should afford the parties procedural fairness.
After having discussed the fall in February 2015 the arbitrator came to the conclusion [87]:
In my view, there is no evidence that Mr Massih's hip condition was rendered symptomatic as a result of the injuries suffered on 17 April 2014, specifically his knee injury, either in a direct or indirect fashion. (my underlining)
Accordingly, it seems that the arbitrator considered whether the knee injury incurred during the work accident resulted in the fall in February 2015 and whether this caused the degenerative condition of the left hip to become symptomatic, rather than whether it was the accident in 2014 which caused the hip to become symptomatic. This is also illustrated by the finding [90]:
Furthermore, there is no medical evidence explaining why Mr Massih's knee collapsed in February 2015 and whether this is in any way related to the condition of his knee and the injuries received in April 2014 or indeed whether the symptomatic condition of Mr Massih's hip stems from this event.
At [89] the arbitrator returned to the correct question and acknowledged that the evidence 'suggests' that Mr Massih's hip condition was symptomatic from April 2014 onwards, although it was not identified earlier, but then concluded that the evidence did not prove this. The arbitrator said the following in this regard:
Rather, the majority of the evidence only goes so far as to suggest that Mr Massih's specific knee injuries were the original focus of attention as they were the worst injury he suffered. Once these had been addressed it was apparent that there were ongoing symptoms in his knee that may have been referred pain from his hip. This suggests (but of itself does not prove) that Mr Massih's hip condition was symptomatic from April 2014 onwards, although it was not identified earlier due to other more specific injuries. This does not support the conclusion that the hip injury is a consequence of the knee injury.
Despite acknowledging that the evidence suggested that the knee symptoms might have been in reality referred pain from the hip from April 2014 onwards, the arbitrator concluded that this had not been proven. Further, he again strayed from the relevant question, ie, whether the hip injury was caused in April 2014, by asking whether the hip injury was 'a consequence of the knee injury'.
Accordingly, I am satisfied that the first ground of appeal, namely that the arbitrator failed to consider whether an injury to the left hip occurred on 15 April 2014, is made out.
Particular 1(a) of the first ground of appeal also has some merit, because the arbitrator did not refer in his reasons to Mr Massih saying in his statement that his left leg remained on the floorboards in a 'twisted' position. However, this is but a minor aspect of the arbitrator misconceiving the evidence. More importantly, he misconceived the submission that the pre‑existing degenerative condition of the hip was rendered symptomatic by the left hip being injured as a result of the twisting of the left leg during the accident. Instead the arbitrator seemed to focus on whether the left hip was rendered symptomatic by the knee injury or by reason of the fall in February 2015.
There also seems to be some merit in particular (b) of the first ground of appeal. That particular alleges that the arbitrator took the approach that he could only consider any injury to have arisen from the work accident on 15 April 2014 if it was identified on the First Medical Certificate, Form 2B, as an injury. This form only described the injury as 'twisting of knee & leg (left) slight abrasion'.
The arbitrator set out at [9] that Western Power's contention was that it could not be liable for Mr Massih's hip replacement operation, as it had never admitted liability to pay compensation in respect of a hip injury arising from the accident. The arbitrator also acknowledged at [10] Mr Massih's argument that Western Power was responsible for the medical or surgical treatment required as a result of all injuries received during the work accident, whether they were recorded on Form 2B or not. The arbitrator then came to the conclusion at [15] that it would be the wrong inquiry to consider whether Mr Massih's hip problems were captured by any 'particular limb of the definition of injury'. It does not seem that the arbitrator was referring to the definition of injury in the Act, but rather to the definition or description of the injury on Form 2B. The arbitrator then correctly identified at [19] the essential question as being whether Mr Massih's hip problem was rendered symptomatic by the fall in April 2014.
However, towards the end of his decision at [125] the arbitrator came to the conclusion that he was not persuaded that Mr Massih's hip condition and the need for surgery resulted from the accident in April 2014. He added that he was also not satisfied that Mr Massih's hip condition was 'encompassed by Western Power's admission of liability for injuries sustained in that fall'. This seems to indicate that the arbitrator returned to Western Power's argument that Mr Massih was not entitled to claim the costs of surgery to his hip because a hip injury had not been referred to on Form 2B.
The arbitrator appears to have accepted the argument by Western Power as he stated at [126] that he agreed with Western Power that in the circumstances Mr Massih was required to bring a 'fresh claim' in regards to his hip injury. It is not clear what the purpose might be of Mr Massih bringing a 'fresh claim' for the hip injury where the arbitrator had already found that the hip injury was not caused by the accident in 2014. This observation could possibly have been intended to relate to a fresh claim made on the basis that Mr Massih received the injury to his hip when he had a fall in February 2015. However, according to the progress notes by Dr Wright, this fall happened at work and by reason of Mr Massih's left knee giving way, which had been injured in the accident of April 2014.
Accordingly, any claim that the pre-existing osteoarthritis was rendered symptomatic because Mr Massih had a fall in February 2015 when his knee gave way should in any event have been part of the same claim, perhaps as an alternative to saying that the pre‑existing osteoarthritis was aggravated by the fall through the floorboards in 2014. As indicated earlier, Mr Massih did not rely on such an alternative claim, but the arbitrator considered it nevertheless. It seems that the arbitrator may have thought that the alternative claim was the only basis on which Mr Massih could recover the costs of the hip surgery and was of the view that such an alternative claim would have to be brought as a separate claim.
Accordingly, despite the arbitrator's rejection of Western Power's argument at the beginning of the decision, he seems to have come to the conclusion that Mr Massih could not rely on a hip injury received during the work accident in April 2014, because the hip injury had not been listed on Form 2B.
I did not receive submissions from either party on the issue whether the employer's liability to pay compensation is limited by the description of the injury in Form 2B or by the acceptance of liability indicated by the employer's insurer in Form 3A. The insurer of Western Power stated in Form 3A that liability was accepted and the form recorded the 'nature of incapacity' as 'left knee strain, neck, lower back pain and bruising to abdomen'. This wording is slightly different to the description in Form 2B which was 'twisting of knee & leg (left) slight abrasion'.
It is unnecessary to decide for the purposes of this appeal whether the liability of the insurer of the employer is limited to the injuries listed in Form 2B or the incapacity stated in Form 3A. My prima facie view is that there is no indication in the Act that this should be the case. Section 18 of the Act simply states that if an injury of the worker occurs, the employer shall, subject to the Act, be liable to pay compensation in accordance with sch 1. An injury is defined in s 5. This indicates that the employer is liable to pay compensation in respect of any injury that was in fact caused by a work accident or occurred in the course of the work.
It would be surprising if the worker had to file a separate claim in the event of it being discovered at a later stage that he had incurred a further injury during the work accident, which had remained undetected or undiagnosed for some time. At best, the worker might be required to amend the Form 2B. However, I do not wish to make any findings in that regard without the matter having been fully argued before me.
It is not necessary to come to a conclusion whether the arbitrator's reliance on Western Power's argument that the hip injury was not referred to in Form 2B was an error, as I have already concluded that the arbitrator applied the wrong test and did not consider whether the hip injury was caused during the work accident or, put differently, whether the pre‑existing osteoarthritis was rendered symptomatic as a result of the fall through the floorboards.

Ground 2 - whether the arbitrator incorrectly applied the Briginshaw v Briginshaw test

The arbitrator referred at [26] of his decision to the fact that Mr Massih carried the burden of establishing his case 'to the requisite standard'. The arbitrator then said:
Accordingly, Mr Massih has the obligation to prove his case to the balance of probabilities and must lead sufficient evidence to persuade me of the likelihood of the facts necessary to answer his case in the affirmative – see Briginshaw v Briginshaw (1938) 60 CLR 336.
It could, of course, have been the case that the arbitrator meant to apply the ordinary 'on a balance of probabilities test' and simply referred to Briginshaw v Briginshaw believing it to be authority for the proposition that in civil matters a balance of probabilities test applies. However, Briginshaw v Briginshaw very specifically deals with the higher level of satisfaction required in cases which involve serious allegations of 'moral delinquency'.
It is also apparent from the manner in which the arbitrator assessed the evidence that he required a level of exactness of proof by Mr Massih, which was not necessary and involved an unduly high expectation of the level of evidence required before a finding could be made in favour of Mr Massih on a balance of probabilities. As I will explain in the course of this judgment, the arbitrator essentially required Mr Massih, and particularly his medical experts, to explain the reason for every pain that he had, exactly when it started and when it ceased, what it was caused by and insisted on a level of detail and exactness in the evidence which is not generally forthcoming in the workers' compensation jurisdiction. Apart from Mr Massih's cross‑examination the arbitrator decided the application on the basis of Mr Massih's written statement (which was used as his evidence‑in‑chief) and the respective medical practitioners' reports without the medical experts being called to give evidence. The evidence was therefore limited to what had been stated in the reports. This is not unusual in the workers' compensation jurisdiction.
I accept that the medico‑legal report obtained from Professor Khan was very brief in providing information and explanations and only dealt with the questions posed by the instructing solicitors which were somewhat limited. The questions asked could have been more detailed in order to elicit why Professor Khan was of the view that the hip injury had been caused by the work accident and why the pain in Mr Massih's knee was only diagnosed as being related to the hip problem more than a year after the accident.
Nevertheless, for the reasons that follow, I am of the view that the arbitrator required an unnecessarily high level of satisfaction and exactness of proof. He did apply a Briginshaw v Briginshaw type test, even though this is not applicable to matters in the workers' compensation jurisdiction. No serious allegations of fraud, commission of a crime or adultery had been made by Mr Massih.
Accordingly, ground of appeal 2 has been made out.

Ground 3 – whether the arbitrator should have applied the but for test

The third ground of appeal alleges that the arbitrator erred in not applying the but for test to the question whether the hip problems had been caused by the work accident.
It is generally accepted that the same principles applying to causation in tort law also apply to proof that the worker's incapacity to work or symptomatology is causally related to his work injury: Cole v P & O Ports Ltd [2002] WASCA 157 [22] – [24]; and Napier v BHP Billiton (Worsley Alumina) Pty Ltd [2015] WASCA 230 [93].
In Cole v P & O Ports Murray and Wheeler JJ cited with approval the decision in Kooragang Cement Pty Ltd v Bates (1994) 35 NSWLR 452, 463, where the Court of Appeal of New South Wales applied the usual test of causation in tort to the question whether the incapacity of a worker had arisen from the relevant work injury. Kirby P (Sheller and Powell JJA) said the following in this regard [93]:
To return workers' compensation law in relation to causation to that state is to place it on all fours with the general law of causation stated in relation to negligence cases by the High Court in the leading authority of March v Stramare Pty Ltd (1991) 171 CLR 506. The headnote of that case accurately summarises the effect of the judgments of the majority by saying that, 'causation is essentially a question of fact to be answered by reference to common sense and experience and one into which considerations of policy and value judgments necessarily enter. The "but for" or causa sine qua non test is not a definitive test of causation'. That approach to the question has since been adopted in many cases concerned, not only with the question whether a plaintiff's injury was caused by a defendant's negligence, but also with the question whether damages claimed were caused by a plaintiff's injury.
There are many more High Court cases following March v E & MH StramarePty Ltd (1991) 171 CLR 506, which have made it clear that the 'but for' test is not in itself a sufficient test of causation. It may be the starting point to exclude causes which do not satisfy the but for test, but even if a cause does satisfy this test considerations of policy and value judgments are also relevant, particularly where subsequent events occur which could be said to have broken the chain of causation: Medlin v State Government Insurance Commission (1995) 182 CLR 1, 6. See also Cole v P & O Ports Ltd [25].
Counsel for Mr Massih submitted that Mr Massih would not have had a symptomatic hip and would not have required a hip replacement operation but for the work accident occurring. In the context of this case, where there was no allegation that an event subsequent to the work accident had broken the chain of causation, it would indeed have been sufficient if Mr Massih had proven that without the work accident his degenerative condition of the hip would not have become symptomatic, at least not in early 2015. If this is what was meant by counsel for Mr Massih by saying that the arbitrator should have applied the but for test, that would be correct, but at the same time, the arbitrator did not make any error by saying that the but for test was not conclusive.
Instead of referring to the but for test, the correct question that should have been asked was whether the work accident made a material contribution to causing the hip symptomatology even though Mr Massih suffered from pre-existing osteoarthritis or degenerative changes in his hip. It is well established law that in order to establish a causal link between the work injury and the worker's incapacity, it is sufficient if the work injury made a material contribution to causing that incapacity: Leggett v Argyle Diamond Mines Pty Ltd [2000] WASCA 182 [22] ‑ [26].
The arbitrator was correct when he stated that it was 'over‑simplistic to suggest that "but for" the initial injury Mr Massih would not have required surgery'. The arbitrator correctly identified the question of causation as requiring him to assess whether the symptomatology/incapacity arising from the hip was caused, at least materially, by the work accident. The arbitrator correctly referred to Leggett v Argyle Diamond Mines [22].
However, the arbitrator did make an error when he rejected the submission by counsel for Mr Massih that Western Power carried an evidentiary burden to present evidence to prove that the pre‑existing osteoarthritis would have become symptomatic by early 2015 in any event, irrespective of the work accident. Counsel for Mr Massih had submitted, correctly, that it was for Western Power to 'disentangle the competing causal connections' in accordance with Watts v Rake (1960) 108 CLR 158. The arbitrator should have accepted the submission by counsel for Mr Massih in that regard.

In Watts v Rake (159 – 160) Dixon CJ held that it was well established in tort law that the plaintiff bore the legal burden of proof that his or her loss or disability has been caused by the tort or accident. However, proof that the tort made a material contribution to the loss or disability was sufficient. Where a plaintiff had showed satisfactorily that prior to the tort or accident he had been able to lead an active life both in work and recreation and that the injury sustained in the accident had been a course of his disability he was prima facie entitled to all damages flowing from that disability. Dixon CJ then went on to explain how the burden of proof operated in situations where there were competing causes to the loss or disability. His Honour said the following in that regard:
If the disabilities of the plaintiff can be disentangled and one or more traced to causes in which the injuries he sustained through the accident play no part, it is the defendant who should be required to do the disentangling and to exclude the operation of the accident as a contributory cause. If it be the case that at some future date the plaintiff would in any event have reached his present pitiable state, the defendant should be called upon to prove that satisfactorily and moreover to show the period at the close of which it would have occurred.
In Purkess v Crittenden (1965) 114 CLR 164, 168, 170, the High Court made it clear that the burden of proof referred to by Dixon CJ in Watts v Rake was an evidentiary onus (a burden to place relevant evidence before the court) and that the overall legal onus of proving that the tort or accident made a material contribution to the plaintiff's disability remained with the plaintiff.
If these principles regarding the burden of proof in tort law were applied to workers' compensation, the worker would upon an application for compensation carry the legal burden of proving that his incapacity was caused, in the sense of materially contributed to, by the work injury and the employer would have an evidentiary burden to show that there were pre‑existing conditions which would in any event have resulted in the incapacity manifesting itself at that time.
Counsel for Mr Massih was quite correct in saying that it was for Western Power to present evidence to show that the pre‑existing degenerative condition in the hip was the sole cause of Mr Massih's symptomatology/incapacity arising from the hip and that symptoms would have manifested themselves in any event by early 2015 without the work accident having occurred. As I will discuss later, no such evidence was presented by Western Power. On the contrary, the arbitrator seems to have expected Mr Massih to present evidence that the pre‑existing osteoarthritis would not have become symptomatic as early as 2015 if the accident had not occurred.
Although the arbitrator's rejection of Mr Massih's reliance on Watts v Rake was not specifically raised as a ground of appeal, it seems to me to be essentially the complaint raised by Mr Massih's counsel when he says that the arbitrator should have applied the but for test. As held by Dixon CJ in Watts v Rake, where the plaintiff proves a causal connection between the defendant's negligent act and a subsequent injury or disability, a prima facie conclusion may be drawn that it was the negligent act which was the sole cause of the injury or disability. If the defendant wishes to establish otherwise, he or she has an evidentiary burden to do so.
Accordingly, I am of the view that the arbitrator also made an error in law by not requiring Western Power to present evidence that the pre‑existing osteoarthritis would have resulted in the same symptomatology in 2015 in any event, but expecting Mr Massih, at least by implication, to prove that the pre‑existing osteoarthritis would not have done so.

Mixed errors of law and fact made in applying the incorrect test regarding causation and the incorrect standard of proof to the evidence

I shall next deal with how the arbitrator assessed the evidence and how the errors of law that I have identified in respect of each ground of appeal led him to make the wrong findings.
For the purposes of the application, three medico‑legal reports were obtained, one on behalf of Mr Massih and two on behalf of Western Power. Professor Khan produced a report, dated 1 September 2015, in response to specific questions asked by Mr Massih's instructing solicitors. Professor Khan described the work accident as 'a significant one'. He said the fact that the left leg remained on the floorboards while the right leg was dangling down, caused 'a significant twisting injury to both knee, hip and spine'.
Professor Khan explained that when he first met Mr Massih in April 2014 the knee pain was most notable and compromised Mr Massih's ability to mobilise. Professor Khan commented that after the arthroscopy of the left knee the knee pain had improved significantly so that Mr Massih was 'now able to note pain in the other areas'. It is not clear whether Professor Khan meant that Mr Massih was able to note pain in other areas in May 2014 or at the time of his report in September 2015. Presumably he was referring to 2015, as his earlier reports to Dr Wright indicated that Mr Massih was still complaining about knee pain in 2014.
Professor Khan specifically stated in his report of September 2015 that Mr Massih first commented on pain in his groin region on 5 May 2015. Professor Khan elaborated that at that time Mr Massih had a 'complete loss of internal rotation of his left hip and marked pain on any attempt at rotation'. The pain had become significantly worse then. Professor Khan added that the pain was radiating to Mr Massih's left knee and affected his mobility and ability to work.
In response to a question what the 'exact diagnosis of the hip injury' was Professor Khan answered 'osteoarthritis of the left hip'. When he was asked whether the hip injury was work‑related, Professor Khan gave the following answer:
Unfortunately I am unable to state that the hip condition of osteoarthritis is specifically and directly related to his work-related accident in April of last year. Tony had never had pain in his hip before the accident and this was the only significant event that had occurred to him in that period. It is not unreasonable to say that the accident was at least partially responsible for bringing about his symptoms and therefore requirement for a hip replacement.
In my view, the only sensible conclusion that one can draw from this statement is that Professor Khan was of the view that the work accident had not directly caused the osteoarthritis and that it was pre‑existing. However, he was of the opinion that the work accident was 'partially responsible' for causing the pre‑existing osteoarthritis to become symptomatic as this was the 'only significant event' that had occurred to Mr Massih in that period.
Professor Khan did not go further and express an opinion to the effect that the osteoarthritis was unlikely to have become symptomatic without the work accident occurring. But as I have explained, it was not for Mr Massih to present evidence that without the work accident his osteoarthritis would not have become symptomatic in early 2015. It was for Western Power to present evidence that without the work accident the pre‑existing osteoarthritis was likely to have become symptomatic in any event by early 2015.
Western Power obtained a medico‑legal report from Mr Frederick Phillips, also an orthopaedic surgeon. Curiously, he produced two reports, each dated 19 October 2015, each containing the same history of the events, current symptoms, results of examination and summary and assessment. The two reports, however, answer a totally different set of questions posed by the instructing solicitors.
The results of Mr Phillips' physical examination are the same in both reports. He found that there was no significant abnormality in the upper limbs and that there was an excellent range of movement in the thoracolumbar spine. With regard to the lower limbs, Mr Phillips stated that Mr Massih's ability to raise a straight leg was markedly restricted by a complaint of back pain. Mr Phillips reported that examination of Mr Massih's hip proved 'extremely difficult in that I could not get him to relax'. He said that he could not get Mr Massih to flex the left hip to about 70 degrees, although Mr Phillips felt that a greater range was in fact possible. He could not assess abduction and adduction. Mr Phillips said that it was his impression that 'there was some restriction in internal rotation'.
In his 'summary and assessment' Mr Phillips said that the fall through the floorboards would certainly have caused a strain to the medial collateral ligament of the left knee. It would not have caused the medial meniscal tear (which was repaired during the arthroscopy). However, Mr Phillips also stated the following:
With the benefit of hindsight it would appear to me that the most likely cause of knee symptoms which were not addressed by surgical treatment were in fact originating from his hip.
This is not an uncommon occurrence in orthopaedic practice for both surgeons and patients to initially consider the knee as the pain generator when in fact it is referred pain from an osteoarthritic hip, and I refer to Mr Massih's original description to me of his pain in that he stated that he initially could not localise the pain.
On the other hand he clearly did have a medial ligament injury which would have caused a small effusion as had been identified on the first MRI scan and clearly this would have been reasonable for the knee to have been the original focus of attention at the lower limb.
This opinion expressed by Mr Phillips seems to support the fact that Mr Massih's ongoing complaints about his left knee were partly misdiagnosed in that Professor Khan did not initially consider the possibility that the knee pain originated from an injury of the hip or an aggravation of a degenerative condition of the left hip. Mr Phillips said quite clearly that it is most likely that the cause of the knee symptoms which had not been dealt with by the arthroscopy were in fact originating from Mr Massih's hip. Those knee symptoms arose as early as May 2014, because the knee remained painful and later gave way, despite the arthroscopy having been performed on 1 May 2014.
The fact that Mr Phillips concluded that Mr Massih also had a medial ligament injury, in addition to the meniscal tear, does not mean that he contradicted his earlier statement about the hip being the cause of the knee problems. He simply added that this medial ligament injury would have also caused pain to the knee after the arthroscopy and this would have made it more difficult for Mr Massih and Professor Khan to differentiate between the knee pain caused by the medial ligament injury and the referred knee pain caused by his hip.
In my view, Mr Phillips expressed the opinion that part of Mr Massih's knee pain was likely to have been generated by symptoms arising from the osteoarthritis in the hip as early as May 2014. He does not offer any opinion that the work accident was causally unrelated to the hip problem (originally diagnosed as pain in the knee) becoming symptomatic.
When Mr Phillips was specifically asked whether the hip symptoms were 'directly related' to the work accident or whether the accident was a contributing factor to the hip symptoms, he gave the following reply:
The pathology and symptoms are not directly related to the accident though I have raised the possibility that a forced abduction could have precipitated symptoms at the left hip though groin symptoms were never recorded at that time and value recorded some time later.
Given that he now relates hip symptoms to groin symptoms it would be reasonable to assume that the original symptoms felt at the knee were originating from the knee, not the hip.
As I understand this answer, Mr Phillips again says the forced abduction of the leg during the accident could have precipitated symptoms at the left hip, although they were not recorded at that time. However, he then adds that because Mr Massih never complained of groin symptoms in the months after the work accident but only in 2015, it would be reasonable to assume that the earlier symptoms felt at the knee were originating from the knee and not the hip. The latter statement appears to be contradictory to what Mr Phillips said earlier under the heading 'summary and assessment', namely:
With the benefit of hindsight it would appear to me that the most likely cause of knee symptoms which were not addressed by surgical treatment were in fact originating from his hip.
When Mr Phillips was asked whether the left hip symptoms were caused, exacerbated or aggravated by any pre‑existing condition, he answered 'I could not speculate'. It is difficult to understand what Mr Phillips meant by that answer, unless he wanted to indicate that he did not know when the osteoarthritis in the hip had commenced.
Mr Phillips was also asked to give an opinion to what extent, if any, the work accident aggravated, accelerated or exacerbated 'the existing arthritis'. To this question Mr Phillips answered 'There is no evidence that the accident actually aggravated or accelerated the hip pathology'. However, this question was premised on Mr Massih having 'existing arthritis', whereas Mr Phillips said earlier he could not speculate as to whether a pre-existing condition had exacerbated or aggravated the left hip symptoms.
Mr Phillips was also asked the question whether it was likely that, given his age, Mr Massih would have suffered the left hip symptoms irrespective of the accident. To this question Mr Phillips answered 'That is the most likely scenario'. However, the question was open‑ended, in the sense that it related to whether Mr Massih would have suffered left hip symptoms in any event during the course of his lifetime, rather than in 2015.
It is frankly difficult to make any sense of the answers provided by Mr Phillips in respect of the crucial issues. However, a question answered in the second report produced by Mr Phillips on the same date may shed some light on his opinion. Mr Phillips was asked whether Mr Massih's complaints were consistent with the mechanism of injury described by him and upon Mr Phillips' examination. To this, Mr Phillips answered:
I have detailed examination findings suggesting an element of pain exaggeration.
The only complaints that would have been consistent with a mechanism of injury would have been a temporary soft tissue strain at the neck and low back and a medial collateral ligament strain, partial tear at the left knee.
The injury could possibly have aggravated a pre‑existing osteoarthritis of the left hip given a forced abduction that may have occurred.
However contemporary examinations did not identify any hip symptoms and I have commented on possible inconsistency here.
This answer seems to indicate that Mr Phillips is of the view that Mr Massih may be exaggerating his pain, generally and at the hip, because Mr Phillips had not identified any hip symptoms on examining Mr Massih. These comments fit in with Mr Phillips' view, which I shall discuss later in relation to the fourth ground of appeal, that he was not convinced that Mr Massih needed a hip replacement at that stage.
However, with regard to the question whether the work accident made a contribution to the hip symptoms experienced by Mr Massih, Mr Phillips is clearly supportive of the view that the work accident could have aggravated a pre‑existing osteoarthritis of the left hip. Mr Phillips then added that the fact that hip symptoms were not identified in 2014 raised a possible inconsistency.
Although Mr Phillips raised questions about why Mr Massih did not identify pain in the groin at an earlier stage, he certainly did not come to any conclusion that Mr Massih had pre‑existing osteoarthritis and that this would have caused symptoms by 2015 in any event irrespective of the work accident.
The third medico‑legal report was obtained from Dr Michael Bowles, an occupational physician. He noted in his report of 4 September 2015 that he had reviewed Mr Massih on three occasions, but only the report of 4 September 2015 was before the arbitrator and is before me on appeal.
Dr Bowles referred to the fact that the radiological report concerning the MRI of the left hip showed moderate‑severe osteoarthritis in the left hip joint. Dr Bowles noted that the hip arthritis was asymptomatic prior to the accident. He referred to pain diagrams which he had prepared on each occasion when he saw Mr Massih, namely on 3 July 2014, 20 October 2014 and 26 March 2015. The first two pain diagrams did not indicate any groin complaints. However the pain diagram prepared on 26 March 2015 showed pain emanating from the left groin, running down the inside of the left upper leg and into the whole of the lower left leg and foot. The pain was rated by Mr Massih to be at a level of 3 ‑ 4 ½ out of 10.
Dr Bowles concluded that in his view the hip symptoms were not directly related to the accident and that the accident had not led to an aggravation of the existing arthritis. Dr Bowles explained that if that had been the case, one would have expected 'significant symptomatology' arising prior to 26 March 2015. Dr Bowles also expressed the view that osteoarthritis in the left hip was a very common problem in the general population as one aged and that it was likely to have led to left hip symptoms in due course irrespective of the accident. Again, Dr Bowles is not specifically asked to comment on whether the pre‑existing osteoarthritis was likely to have led to hip problems as early as 2015.
Dr Bowles based his opinion that the work accident had not caused an aggravation of the pre‑existing osteoarthritis on the fact that Mr Massih did not complain about groin or hip pain before March 2015. However, Dr Bowles does not deal with the reported knee pain and with the opinions of Professor Khan and Mr Phillips that at least some of the knee pain could have been referred symptoms from an aggravation of the pre‑existing condition at the hip. I would not have relied on Dr Bowles' view in preference to that of Professor Khan and Mr Phillips, because Dr Bowles did not consider the possibility that the reported knee pain was in fact originating from the hip and also because he is not an orthopaedic surgeon, but an occupational physician. However, the arbitrator also did not rely on Dr Bowles' report. It is not necessary to go into the reasons for this.
I accept that the medico‑legal report from Professor Khan is very brief and that the reports from Mr Phillips are difficult to understand and that some of the answers he gives appear to be contradictory. However, Professor Khan is quite firm in his finding that the work accident was at least partially responsible for bringing about the symptoms, as the degenerative condition of the left hip had been asymptomatic before the accident and the work accident was the only significant event that had occurred in that period.
Professor Khan's opinion expressed in the report of 1 September 2015 needs to be read together with his earlier reports to Dr Wright. These show that both Professor Khan and Dr Wright were asking themselves questions as early as June 2014 with regard to whether the knee pain could have been caused by the accident and both had trouble diagnosing the source of the knee pain. Professor Khan did not say in his report of September 2015 that he misdiagnosed Mr Massih's knee pain in 2014 and that he should have realised earlier that this may have emanated from osteoarthritis in the hip. However, this is implied in his reports.
Mr Phillips spelled this out clearly when he concluded that with hindsight the most likely cause of the knee symptoms which were not addressed by the arthroscopy were originating from the hip. He also explained that it was not an uncommon occurrence in orthopaedic practice for both surgeons and patients to initially consider the knee as the pain generator when in fact it was referred pain from an osteoarthritic hip.

That evidence, taken together, was sufficient to prove on a balance of probabilities that the symptomatology of the left hip was materially contributed to by the work accident or, put differently, that the work accident aggravated the pre‑existing osteoarthritis to a significant degree. No evidence had been produced by Western Power that the osteoarthritis in the hip would have become symptomatic in early 2015 in any event, irrespective of the work accident.
Despite this evidence, the arbitrator was not satisfied that it had been proven on a balance of probabilities that the work accident aggravated the pre‑existing osteoarthritis and that the work accident was a significant contributing factor to that aggravation. This seems to be because he required an exactness of proof and detail of explanation which was not necessary.
The arbitrator focused at length at [56] – [78] on the fact that various symptoms were reported in the knee from time to time, ranging from pain on the lateral aspect of the knee to additional pain, reported later, on the medial side of the knee, to subsequent giving way of the knee. The arbitrator was concerned that there was no adequate explanation by Mr Massih or his medical practitioners of each of the respective knee problems, when they arose, how long they lasted and what they could be ascribed to. At [56] the arbitrator challenges Professor Khan's statement in his report of 9 March 2015 to Dr Wright that Mr Massih's symptoms had persisted. The arbitrator notes that this is not strictly correct as the symptoms in the knee seemed to have changed.
At [101] the arbitrator was concerned that Professor Khan had not explained 'the hiatus' in Mr Massih's symptoms or the nature of any referred pain to the knee. The 'hiatus' in Mr Massih's knee symptoms can only refer to the period when he was on holidays in Lebanon, because there are regular entries in Dr Wright's progress notes about knee pain and ongoing issues with the knee. It is true that Professor Khan could have explained a bit better why the fact that the osteoarthritis in the hip was rendered symptomatic initially manifested itself as pain in the knee. However Mr Phillips made it clear that pain in the knee can originate from an osteoarthritic hip and that such knee pain is not uncommonly misdiagnosed by surgeons in orthopaedic practice and patients alike.
The arbitrator also seems to have been concerned at [101] that there was no explanation as to why Mr Massih's knee kept on collapsing from about February to May 2015, but that this had not occurred afterwards. However, the arbitrator had before him, and referred to, a report by the physiotherapist of 1 May 2015 in which it was recorded that after Mr Massih had used a knee brace and had been given some specific strengthening exercises, he had not reported any further occasion of the knee giving way.
The arbitrator acknowledged at [121] that Professor Khan had provided 'the most unequivocal assessment of whether the condition of Mr Massih's hip resulted from the fall of April 2014', but then came to the conclusion that Professor Khan did not have any regard to the fall in February 2015. However, the letter from Dr Wright to Professor Khan, dated 4 March 2015 described in detail that Mr Massih's left knee had given way repeatedly, that he had a further injury at work when the knee gave way and that Dr Wright was concerned about his safety at work. Professor Khan also mentioned in his report to Dr Wright of 9 March 2015 that Mr Massih's knee had occasionally given way. This means that Professor Khan did consider the fact that Mr Massih's knee had given way and it is unlikely that he overlooked Dr Wright's report that Mr Massih had a further injury at work when his left knee gave way.
Despite having the information about the knee giving way Professor Khan expressed the opinion in his letter to Dr Wright of 9 June 2015 that the osteoarthritis of the left hip demonstrated by the MRI was likely to have been caused by the accident in 2014, as the hip had been asymptomatic before. Professor Khan specifically stated that the accident had brought about a premature end to Mr Massih's working life. Professor Khan therefore dismissed, by implication, the possibility that the osteoarthritis in the hip might have been rendered symptomatic by a fall when the knee gave way.
At [103] the arbitrator expressed the concern that Professor Khan had not explained why he had 'changed his unequivocal view' that any relief from a diagnostic injection of March 2015 would establish that Mr Massih's problem was intra‑articular to the knee. Professor Khan wrote to Dr Wright on 9 March 2015 stating that it was difficult to say what was going on with Mr Massih, as he still had pain on the medial side of his knee, even though the latest MRI showed no significant abnormality in the knee. Professor Khan noted that he had arranged for a diagnostic injection into the knee and expressed the view that if this provided relief 'even for an hour', one could be sure that the symptoms were intra-articular.
In a further report by Professor Khan to Dr Wright on 5 May 2016 he stated that the knee pain had improved for four days with the diagnostic injection, but then returned. Professor Khan added that on examination Mr Massih now had complete loss of internal rotation of the left hip and expressed the concern that the symptoms in the knee might be emanating from an arthritic hip. It is apparent from that report that even though the diagnostic injection had provided Mr Massey with some relief, Professor Khan was starting to focus his attention on the possibility that osteoarthritis in the left hip had caused the pain in the knee.
In my view, the arbitrator unnecessarily focused on the various symptoms experienced by Mr Massih from time to time at the left knee. A detailed explanation by Mr Massih or his medical practitioners of the various knee pains, how long they lasted, what their causes were, and to what extent they were resolved, was not necessary, as it was accepted by Professor Khan, Dr Wright, and also Mr Phillips that at least some of these knee problems were likely to have been referred pain from the osteoarthritis in the hip that was undiagnosed at that stage.
The arbitrator came to the conclusion at [105] that 'notwithstanding Professor Khan's expertise and his familiarity with Mr Massih's condition as his treating orthopaedic surgeon', he was not satisfied that any 'significant weight' could be afforded to Professor Khan's conclusions, because he did not appear to have proper regard to the facts, offered no explanation as to why Mr Massih's symptoms changed or indeed what those symptoms were and did not explain his 'change in diagnosis' of Mr Massih's knee pain.
In my view those findings were not properly made on the evidence before the arbitrator and they seem to have arisen from his demand of an overly high level of satisfaction, more in line with Briginshaw v Briginshaw than with the arbitrator's duty to act 'in accordance with the substantial merits of the case' (s 188 of the Act) or to be satisfied on a balance of probabilities.
Accordingly, the arbitrator not only applied (towards the end of his decision) the wrong test regarding causation and an overly stringent standard of proof, he also made wrong findings of fact occasioned, at least in part, by the wrong application of the law.

Ground 4 – whether the arbitrator took into account irrelevant considerations when deciding whether the hip replacement operation was reasonable

Counsel for Mr Massih submitted that the arbitrator erred in law because he took into account irrelevant considerations when he came to the conclusion that Mr Massih had not established that the costs of a hip replacement operation were reasonable expenses pursuant to cl 17 of sch 1. Counsel submitted that the arbitrator should not have taken into consideration whether all conservative treatment options had been exhausted and should also not have investigated the issue whether the hip operation would allow Mr Massih Massey to return to work despite the other injuries which he suffered during the work accident.
Clause 17 of sch 1 provides that in addition to weekly payments of compensation payable, a sum is payable equal to the reasonable expenses incurred or likely to be incurred in respect of, inter alia, medical or surgical treatment.
In Napier v BHP Billiton (Worsley Alumina) Pty Ltd [108] Buss JA, with whom Newnes JA agree, came to the conclusion that although cl 17 did not state the required connection between any relevant medical or surgical treatment and the worker's injury, by implication it was required that the medical or surgical treatment be for the purpose of alleviating, remedying, curing or preventing the deterioration of the injury compensable under the Act, or a disability that was wholly or partly caused by or attributable to the compensable injury or any symptoms or effects wholly or partly caused by or attributable to the compensable injury or the disability.
Buss JA further held at [113] that the costs of a particular medical or surgical treatment would be reasonable if it was reasonable for that treatment to be undertaken and the amount of the expenses incurred or likely to be incurred was reasonable in all the circumstances. These matters were a question of fact.
The arbitrator accepted that Professor Khan was of the view that the arthritic hip warranted replacement. Professor Khan added in his report of 1 September 2015 that the work accident was at least partially responsible for the development of symptoms and the need for of a hip replacement operation. Professor Khan had also stated in his letter to Dr Wright of 11 August 2015 that he was of the view that Mr Massih would not be able to go back to the workforce without a hip replacement operation.
The arbitrator referred to Dr Bowles' report of 4 September 2015 and his opinion that a hip replacement operation was 'generally a very good operation with satisfactory results from symptom and function point of view'. The arbitrator inferred from these two reports that Mr Massih was likely to have a good outcome from such surgery and might be able to return to the workforce. The arbitrator also referred to Mr Philips' second report in which he said that there was no reason why Mr Massih should not be able to return to his pre‑accident employment if he had a successful hip replacement operation.
The arbitrator noted that there was no evidence whether such surgery was a common procedure, but said that he was prepared to infer this from the reports of the specialists before him.
The arbitrator then came to the conclusion at [156] that the hip replacement surgery was an accepted procedure with generally good results and that this would address Mr Massih's hip condition.
Despite arriving at this conclusion the arbitrator stated at [137] that it was not appropriate for him to infer that the limits of conservative treatment for Mr Massih's hip condition had been exhausted. The arbitrator referred to the report by Dr Bowles who suggested that replacement surgery might be premature and that cortisone injections should be tried first. However, the arbitrator said that he could not attach much weight to that suggestion as Dr Bowles had specifically said that he would defer to the orthopaedic surgeons regarding whether replacement surgery was warranted.
The arbitrator also referred to Dr Wright's notes which indicated that Mr Massih had a CT guided cortisone injection into his left hip without any effect.
Nevertheless, the arbitrator came to the conclusion that he had 'no idea' whether there were other alternative conservative treatments available and whether a single cortisone injection was sufficient. He came to the conclusion that it was not appropriate for him to infer that a single cortisone injection had exhausted the limits of conservative treatment.
This means that the arbitrator expected Mr Massih to provide evidence to exclude all other options of conservative treatment. Apart from the fact that Mr Massih had largely done so, because Dr Wright had referred in his practice notes to the CT guided cortisone injection into the hip which had no effect, it was for Western Power to lead evidence to show that the hip operation was not necessary because more conservative treatment might also have resolved his symptoms.
It was only Dr Bowles who had expressed a view that it might be premature to rush into a total hip replacement operation but at the same time stated that he would defer to the opinion of the orthopaedic surgeons in this regard. Dr Philip said in answer to a question whether further medical treatment was required that he had great difficulty in clinically assessing the need for treatment and on that basis could not make any recommendation. This comment seems to refer to Mr Phillips' earlier statement that he found it difficult to examine Mr Massih's hips because he could not get him to relax. Consequently, he could not assess abduction and adduction, but was of the impression that there was some restriction in internal rotation in the hip.
It is not clear to what extent the arbitrator relied on his finding that he had 'no idea' whether other conservative treatment was available and to what extent it might have relieved Mr Massih's symptomatology arising from the hip, because the arbitrator did find, at a later stage in his decision that the replacement surgery was an accepted procedure with generally good results and that it would address Mr Massih's hip condition. In so far as the arbitrator did rely on this finding it was an error of fact and also placed the burden of providing relevant evidence incorrectly on Mr Massih.
The main reason why the arbitrator seems to have come to the conclusion that the expense of a hip replacement operation was not reasonable was because it was very expensive [141] and because there was no evidence that the surgery would allow Mr Massih to return to work [146]. The arbitrator referred at [146] to the fact that Mr Massih had also reported neck and back issues.
It is not quite clear from Professor Khan's report of 1 September 2015 whether he was of the view that Mr Massih would be able to perform his normal pre-accident duties on a full‑time basis after the proposed surgery. The question asked by the instructing solicitors in this regard was unclear, because it did not specify whether the question was directed at Mr Massih's capacity to perform his normal pre‑accident duties without the operation or after the operation.
It is possible that Professor Khan may have referred to the post‑operation situation when he said that 'it is unlikely that Mr Massih will perform his normal pre‑accident duties on a full‑time basis until normal retirement age'. This is because Professor Khan added the following:
He strikes me as a very determined gentleman however who is desperately keen to get back to work and I feel that his efforts are genuine. Unfortunately has been knocked sideways by this significant accident which has taken its toll both physically and emotionally. He feels that he has been left in the lurch by his employer who is not supportive of him returning to the workforce and refusing to accept responsibility for the injuries that he has sustained through absolutely no fault of his own. The last time I saw Mr Massey he was tearful and despondent. The only thing that he would like is to be fit and well as he was prior to the accident so that he can return to work in full capacity.
This statement could mean either that Mr Massih was likely to be able to perform his pre‑accident duties on a full‑time basis after the hip replacement operation or that this was doubtful as Mr Massih had been 'knocked sideways physically and emotionally'.
However, it does not matter what Professor Khan meant by that statement, because there is no provision in cl 17 of sch 1 that the expenses to be incurred are only reasonable if they allow the worker to return to his pre‑accident employment. In Napier v BHP Billiton (Worsley Alumina) Pty Ltd [68] Buss JA pointed out that cl 9 of sch 1 made cl 17 applicable in a situation where total or partial incapacity for work did not result from the injury, but the worker was obliged to obtain the relevant medical or surgical treatment. Accordingly, it cannot be a requirement of cl 17 that the worker will be able to return to his pre‑accident duties after the relevant medical or surgical treatment and this was not the test referred to by Buss JA [108].
Accordingly, the arbitrator erred when he came to the conclusion at [157] that he did not have enough evidence to determine whether Mr Massih would have a capacity for employment after the operation in light of his other injuries. The arbitrator also erred when he held at [153] that he was not persuaded as to the reasonableness of the proposed surgery because it might mean that Mr Massih would nevertheless remain totally incapacitated by reason of his other injuries. The incapacity arising from the other injuries was simply not a relevant consideration.
The arbitrator also held at [158] that he had no evidence of how Mr Massih's hip condition had affected his daily existence. However Mr Phillips reported that Mr Massih could not walk, water the garden or shovel. When going shopping he would accompany his wife to the shops but then simply sit and wait for her to complete the shopping. He was also no longer able to enjoy boat and rock fishing and had not returned to playing social soccer.
In any event, the arbitrator accepted that on the basis of the opinion of Professor Khan and Mr Phillips the hip replacement surgery would address Mr Massih's hip condition. Whether this would allow him to return to his pre‑accident work, was not a relevant consideration.
The arbitrator also returned to Western Power's argument that its admission of liability was limited to the neck, back and knee injury. He questioned at [151] why Western Power was continuing to make weekly payments for total incapacity, where the knee injury had resolved and it had never admitted liability with regard to the hip injury. The question why Western Power was making weekly payments of compensation was not relevant to the issue of whether the costs of the hip replacement surgery were reasonable expenses to be incurred for the purpose of alleviating or remedying the hip injury caused by the work accident, or the disability or symptoms resulting from that injury.
Accordingly, appeal ground 4 is also made out.

Findings on appeal

Apart from not seeing Mr Massih being cross‑examined, the evidence before me is the same as was before the arbitrator. The arbitrator came to the conclusion at [48] that Mr Massih gave his evidence truthfully and was candid and direct despite being a poor historian. Accordingly, there is no reason why I should not make the necessary findings of fact.
I am persuaded on a balance of probabilities that Mr Massih's pre‑existing osteoarthritis in his left hip was rendered symptomatic because of the work accident in 2014, even though this condition was initially misdiagnosed. The accident and the resultant aggravation of his pre‑existing disease was a factor which made a material contribution or contributed to a significant degree to his current symptomatology related to his hip. Mr Massih is therefore entitled to compensation in accordance with sch 1.
I am also satisfied on a balance of probabilities that the proposed hip replacement operation will remedy or at least alleviate the disability, in the sense of the inability to walk or stand for long periods, which was at least partly caused by the hip injury sustained during the work incident and will also remedy or alleviate the symptoms of pain that Mr Massih is experiencing in his left groin and left leg. Accordingly, the costs of the proposed left hip replacement operation and any incidental medical expenses are reasonable expenses under cl 17 of sch 1.

The appeal is upheld.