Dywidag Systems International Pty Ltd v Melksham - [2020] NSWWCCPD 41

DETERMINATION OF APPEAL AGAINST A DECISION OF THE COMMISSION CONSTITUTED BY AN ARBITRATOR
CITATION:	Dywidag Systems International Pty Ltd v Melksham [2020] NSWWCCPD 41
APPELLANT:	Dywidag Systems International Pty Ltd
RESPONDENT:	Rodney Stephen Melksham
INSURER:	Allianz Australia Workers Compensation (NSW) Limited
FILE NUMBER:	A1-5332/19
ARBITRATOR:	Mr P Young
DATE OF ARBITRATOR’S DECISION:	10 December 2019
DATE OF APPEAL DECISION:	30 June 2020
SUBJECT MATTER OF DECISION:	Section 4 of the Workers Compensation Act 1987 – whether the Arbitrator was required to determine the pathology arising from an injurious event – Jaffariev Quality Castings Pty Ltd [2014] NSWWCCPD 79 considered and applied
PRESIDENTIAL MEMBER:	Deputy President Elizabeth Wood
HEARING:	On the papers
REPRESENTATION:	Appellant:
Ms K Balendra, counsel
Hicksons Lawyers
Respondent:
Mr G Levick, counsel
Michael Evers & Co
ORDERS MADE ON APPEAL:	1. The Arbitrator’s finding that the respondent suffered injury to his right knee in the form of an aggravation or acceleration of a disease in accordance with s 4(b)(ii) of the Workers Compensation Act 1987 as a result of the respondent’s employment between 26 June 2007 and 30 June 2013 to which employment was the main contributing factor is confirmed. 2. The Arbitrator’s finding that the respondent suffered an injury to his left knee on 26 June 2007 is revoked. 3. The issues of whether the respondent suffered: (a) an injury to the left knee (including the nature of the injury) on 26 June 2007, and (b) an injury to the left knee in the form of an aggravation or acceleration of a disease as a result of the nature and conditions of employment from 26 June 2007 to 30 June 2013 are remitted to a different arbitrator for determination. 4. The Arbitrator’s orders remitting the matter to the Registrar for referral to the Approved Medical Specialists for assessment of the whole person impairment of the cervical spine, both upper extremities, gastrointestinal condition and the right lower extremity are stayed until the outcome of the determination of the injuries to the left knee referred above.

INTRODUCTION AND BACKGROUND

Mr Rodney Stephen Melksham (the respondent) brought proceedings for lump sum compensation pursuant to s 66 of the Workers Compensation Act 1987 (the 1987 Act) in respect of an injury on 26 June 2007 when he fell in the course of his employment. The respondent was employed by Dywidag Systems International Pty Ltd (the appellant) as a builder/carpenter. The respondent alleged injury to the neck, right shoulder, left shoulder, left knee and an upper and lower gastrointestinal condition consequent upon the ingestion of the medication required to treat those injuries.
The respondent also claimed s 66 entitlements in respect of injury to the right and left knees alleged to have occurred as a result of the “nature and conditions” of his employment, which required him to perform heavy lifting, climb up and down ladders and stairs, kneeling and squatting. This was described as an aggravation, acceleration, exacerbation or deterioration of osteoarthritis in both of the respondent’s knees and nominated a deemed date of injury of 30 June 2013, as that date was the last day of the respondent’s employment.
The appellant accepted liability in respect of the injuries to the neck and both shoulders as a result of the fall on 26 June 2007 but disputed the degree of whole person impairment (WPI) claimed. The appellant also disputed liability for:
(a)    the left knee injury on 26 June 2007;
(b)    the respondent’s gastrointestinal symptoms, and
(c)    injury by way of aggravation of the degenerative disease in to the left and right knees as a result of the nature and conditions of the respondent’s employment.
The Arbitrator found in favour of the respondent and issued a Certificate of Determination (COD) in the following terms:
“The Commission determines:
1.     The matter is remitted to the Registrar for referral to Approved Medical Specialists (AMS) to determine the extent of the applicant’s whole person impairment, if any, which results from injury to the applicant’s cervical spine, both upper extremities, left lower extremity and consequential gastrointestinal tract condition with date of injury 26 June 2007.
2.     The matter is also so remitted in respect of injury to the applicant’s right lower extremity with deemed date of injury 30 June 2013.
3.     I request the Registrar place before the AMS a copy of the Application to Resolve a Dispute, a copy of the Reply and a copy of this Certificate of Determination.”
The COD was issued without bearing the name and signature of a delegate of the Registrar. The COD was amended to include the signature of the Registrar’s delegate and the amended COD was issued on 19 December 2019.
The appellant appeals from that determination.

ON THE PAPERS

Section 354(6) of the Workplace Injury Management and Workers Compensation Act 1998 (the 1998 Act) provides:
“(6) If the Commission is satisfied that sufficient information has been supplied to it in connection with proceedings, the Commission may exercise functions under this Act without holding any conference or formal hearing.”
Both parties agree that the appeal can be determined on the basis of the documents that are before me.
I have had regard to Practice Directions Nos 1 and 6, the documents that are before me, and the submissions by the parties that the appeal can proceed to be determined on the basis of these documents. I am satisfied that I have sufficient information to proceed ‘on the papers’ without holding any conference or formal hearing and that this is the appropriate course in the circumstances.

THRESHOLD MATTERS

There is no dispute between the parties that the threshold requirements as to quantum and time pursuant to ss 352(3) and 352(4) of the 1998 Act have been met.
The respondent does not indicate whether the decision appealed against is interlocutory in nature. The appellant submits that although the matter has been referred for assessment by an Approved Medical Specialist, the Arbitrator has determined the issues of injury, so that the appeal from those findings is not interlocutory in nature.
In accordance with the decision in Maricic v Medina Serviced Apartments Pty Ltd,[1] I accept that the Arbitrator’s findings are final and binding in respect of the issues between the parties and are therefore not interlocutory in nature. Leave to appeal the decision in accordance with s 352(3A) is therefore not required.
[1] [2007] NSWWCCPD 196.

PRELIMINARY MATTER

There is no transcript of the proceedings before the Arbitrator. The parties were invited to make submissions on whether the appeal can proceed in the absence of a transcript of the arbitral proceedings.
The appellant submits that while the lack of transcript can be a serious shortcoming and a ground for the matter to be remitted for re-determination, it is not always necessary. The appellant submits that whether an appeal can proceed without a transcript is dependent upon whether the evidence is adequate to allow a fair review of the proceedings. The appellant refers to various authorities for those propositions and submits that in the circumstances of this case, where there was no oral evidence given and the submissions made were largely based on the evidentiary material, the absence of a transcript would not be a bar to the fair determination of the appeal.
The respondent submits that the appeal can proceed and can be determined without the benefit of the transcript. The respondent indicates that it is not clear what issues were raised at the arbitration by the appellant, whether submissions on injury were made or whether the appellant is raising fresh evidence on appeal. The respondent submits that for those reasons, if the appeal succeeds, the matter should be remitted for re-determination before a different arbitrator, rather than be re-determined by a Presidential member.
In those circumstances, I am of the view that the appeal can proceed.

THE RELEVANT EVIDENCE

The respondent’s statement evidence

The respondent provided a statement dated 14 August 2017.[2] The respondent indicated that he commenced employment with the appellant on 21 February 2003 as a building maintenance man. The respondent disclosed that, prior to commencing with the appellant, he had suffered a left shoulder injury. The respondent said he did not recall the exact details but said that he underwent radiological investigations and had a steroid injection and local anaesthetic that eased the pain, which enabled him to return to full duties as a maintenance man/builder. The respondent denied any other injuries prior to the injury on 26 June 2007.
[2] Application to Resolve a Dispute (ARD), pp 1–4.
The respondent described the injury on 26 June 2007. He was building a set of stairs and had put in a landing which was about 1500 mm off the ground. The respondent said he was working on the steps and moving backwards when he fell, landing on the concrete floor about 1.4 metres below where he had been working. He said he landed on his nose, face, right and left shoulders and neck, and as he fell, he twisted, striking his left knee on the concrete. The respondent said that he felt immediate pain in all of those areas.
The respondent said that he attended the Charlestown Medical Centre and Dr Mark Mills, general practitioner from that practice, became his nominated treating doctor, although he saw other doctors from time to time. He said he was off work for about one week and then returned to suitable duties. He reported continuing problems with his right and left shoulders, neck and left knee.
The respondent stated that his left knee never fully recovered, and he had continuous pain in the left knee thereafter, but other pain, such as shoulder pain, was more painful. The respondent said that he returned to full duties but continued to have difficulties with climbing ladders, walking up and down stairs, kneeling, concreting, screeding and finishing and laying vinyl and ceramic floor tiles. The respondent described how he made concrete, which involved shovelling and, because of left knee pain, he had to alter the way he performed that task so that he was putting the weight of the shovel and the concrete on his right knee. He said he would also put his weight on his right knee when tiling. He recalled in 2008 he was working at a Westfield centre and after simply walking around he had to sit down because of left knee pain. He said he began to take glucosamine and fish oil supplements to relieve the pain in his joints and from time to time would require anti-inflammatories.
The respondent stated that he did not directly complain to his treating doctor about the pain until 2012, despite having continued and increasing left knee pain and increasing right knee symptoms. He said he was made redundant on 30 June 2013.
The respondent said that he was referred to various specialists in relation to his injuries and ultimately underwent bilateral total knee replacements in 2015 at the hands of Dr Christopher Dunkley, orthopaedic surgeon.
The respondent provided a supplementary statement dated 15 June 2018.[3] The respondent maintained that during the course of his employment, he was required to place great strain on his knees when tiling, concreting, plumbing, bending, squatting, walking on uneven ground and climbing up and down stairs while carrying heavy equipment. The respondent said that with the increase in pain in the left knee, he placed greater strain on his right knee.
[3] ARD, pp 5–6.
The respondent indicated that after the fall he began to take panadeine forte for the pain and sometimes he would have at least 12 per day. He said he developed gastrointestinal problems. The respondent said that after the bilateral knee replacements, he was able to reduce the amount of panadeine forte he required.
The appellant provided a further supplementary statement dated 26 April 2019,[4] the contents of which are not relevant to this appeal.
[4] ARD, p 7.

The claim form

The respondent completed a workers compensation claim form on 28 June 2007.[5] In that document, the respondent described having slipped over a landing onto a concrete floor. He listed the injuries as injuries to the face, nose, head, right shoulder, left neck and left knee.
[5] ARD, pp 8–9.

The medical evidence of the treatment providers

The treating medical evidence was largely directed to the respondent’s gastrointestinal condition and shoulder and neck complaints. It is only necessary to consider the medical evidence that is relevant to the appeal so that the evidence pertaining to the non-contentious body parts and conditions is not included in this summary.
A Workcover certificate of capacity was issued by Dr Mills on 28 June 2007. The certificate nominated a date of injury as 26 June 2007 and Dr Mills diagnosed facial bruising, soft tissue injury and bruising to the left knee, probable pre-patellar bursa injury, mechanical left sided neck pain and right biceps muscle strain. Dr Mills certified that the respondent was unfit for work until 4 July 2007.[6] Further Workcover certificates of capacity were issued by Dr Mills between 4 July 2007 and 3 September 2007, which certified the respondent as fit for suitable employment.[7] Dr Mills certified that the respondent was fit to return to pre-injury duties on 20 August 2007.[8]
[6] ARD, p 86.
[7] ARD, pp 88–93.
[8] ARD, p 93.
The early radiological evidence consisted of an x-ray of the left knee dated 28 June 2007. The radiologist reported that there was no evidence of a bone injury, no fluid was seen in the joint and there was no soft tissue swelling.[9]
[9] ARD, p 32.
A large body of clinical notes and other medical records from Appletree Family Practice and Brunker Road Medical practice were in evidence.[10] Those documents contained no evidence relevant to the issues on appeal other than an entry made by Dr Mills on 4 July 2007. That entry recorded that the respondent’s left knee and left neck pain settled. The injuries were generally noted to be resolving.[11]
[10] Reply to Application to Resolve a Dispute (Reply), pp 88–601.
[11] Reply, p 95.
On 23 October 2014, Dr Dunkley reported to Dr Duane Crabtree, general practitioner, following a review of the respondent’s bilateral knee arthritis. The history recorded by Dr Dunkley was that the respondent was experiencing increasing pain in the medial aspects of the knees which had been progressively worsening over the years in the context of the respondent’s work as a builder, which he was struggling to perform. Dr Dunkley discussed the respondent’s arthritic condition and gave the respondent local injections of anaesthetic and cortico steroids in order to defer the need for total knee replacements and in an attempt to keep the respondent at work.[12]
[12] ARD, p 63.
Dr Dunkley again wrote to Dr Crabtree on 11 February 2015. Dr Dunkley reported that the respondent’s left knee was deteriorating and causing him significant pain. The respondent was keen to undergo a total left knee replacement and Dr Dunkley arranged for that to be performed on 28 April 2015.[13] On 23 June 2015, Dr Dunkley wrote to Dr Crabtree and confirmed that because of the respondent’s worsening right knee pain, Dr Dunkley had performed bilateral total knee replacements, which appeared to have occurred on or just prior to 23 June 2015.[14]
[13] ARD, p 65.
[14] ARD, p 69.
A pre-operative bilateral knee x-ray dated 27 April 2015 indicated that there was medial compartment degenerative change with loose bodies in the left knee and moderate degenerative change in the right knee with a loose body in the anterior intercondylar space.[15]

The medico-legal opinions

[15] ARD, p 66.

Associate Professor Leon Kleinman, orthopaedic surgeon

A/Prof Kleinman first examined the respondent on 30 May 2014.[16] A/Prof Kleinman noted the details of the injury on 26 June 2007, including the injury to the left knee, the x-ray of the left knee, and the diagnosis of soft tissue injuries. A/Prof Kleinman recorded an extensive history of ongoing problems in the left shoulder and neck and developing right shoulder complaints. A/Prof Kleinman noted constant pain, swelling and giving way in the left knee, as well as similar constant pain in the right knee. A/Prof Kleinman noted difficulties with walking, ascending and descending stairs, kneeling and squatting because of painful knees.
[16] ARD, pp 94–104.
A/Prof Kleinman reviewed the radiological evidence and considered that the findings on the x-ray dated 28 June 2007 were suggestive of early degenerative changes. A/Prof Kleinman was of the opinion that the respondent suffered from constitutional degenerative change in the left knee which was aggravated by the fall when landing on the front of his knee on 26 June 2007, causing patella-femoral joint damage. A/Prof Kleinman was also of the view that the respondent suffered constitutional degenerative changes in the right knee, unrelated to the fall. A/Prof Kleinman assessed 2% WPI in respect of the left knee, in addition to assessments of the cervical spine and both shoulders.
A/Prof Kleinman re-examined the respondent on 31 October 2014. In his report of the same date,[17] A/Prof Kleinman recorded a detailed history of the respondent’s shoulder symptoms and treatment. A/Prof Kleinman noted that the respondent continued to have problems with his knees, the pain was constant, with the left being worse than the right knee, but the left knee pain improved following a recent cortisone injection. A/Prof Kleinman recorded the respondent’s ongoing difficulties as a consequence of the bilateral knee symptoms. Following an examination of the respondent, A/Prof Kleinman opined that the respondent suffered from pre-existing early degenerative change in his left knee prior to the fall in 2007. He formed the opinion that the fall aggravated the degenerative change and rendered it symptomatic. A/Prof Kleinman was of the view that the degenerative changes had progressed, causing stiffness and more pain. A/Prof Kleinman also considered it was likely that the respondent was suffering from degenerative changes in the right knee, which had been aggravated by the nature and conditions of the respondent’s employment. A/Prof Kleinman considered that the respondent would ultimately require total knee replacements in both knees.
[17] ARD, pp 105–113.
On 27 January 2016, A/Prof Kleinman again examined the respondent and provided a report.[18] A/Prof Kleinman noted the respondent had undergone total knee replacements in June 2015 but continued to experience some pain and limitations in both knees. A/Prof Kleinman reviewed the radiological evidence, confirmed his earlier diagnosis and concluded that as the left knee had not stabilised, it was too early to determine the final outcome. In respect of the right knee, A/Prof Kleinman expressed the view that there was 20% WPI, not all of which was due to the constitutional degenerative condition. A/Prof Kleinman recorded 0% WPI of the right knee as a result of the injury on 26 June 2007.
[18] ARD, pp 114–123.
A/Prof Kleinman re-examined the respondent on 4 August 2016 and, on this occasion, assessed the respondent’s losses as 18% after a 10% deduction for the pre-existing degenerative condition in relation to the left knee and 0% WPI of the right knee because all of the impairment was due to the degenerative changes.[19] A/Prof Kleinman repeated those assessments in yet another report dated 31 October 2017 following a further assessment of the respondent’s conditions.[20]
[19] ARD, pp 124–132.
[20] ARD, pp 133–141.
A/Prof Kleinman was then asked by the respondent to provide a further supplementary report addressing specific questions posed by the respondent’s legal representatives. A/Prof Kleinman responded on 27 June 2018.[21] A/Prof Kleinman confirmed that the injury to the left knee in 2007 significantly aggravated the pre-existing changes in that knee. On this occasion A/Prof Kleinman added that it was his view, the nature and conditions of the respondent’s employment, which involved hard physical work, would also have aggravated and accelerated the degenerative osteoarthritic changes. A/Prof Kleinman described the nature of the duties the respondent performed in his employment with the appellant and concluded that the nature of the respondent’s employment would also have aggravated the underlying degenerative changes in the right knee. A/Prof Kleinman reiterated his assessment of 18% WPI in respect of the left knee. He apportioned that WPI as 2% attributable to the injury on 26 June 2007 and 16% as a result of the nature and conditions of the respondent’s employment. In respect of the right knee, A/Prof Kleinman assessed the WPI as 20%, with 18% WPI attributable to the nature and conditions of the respondent’s employment.
[21] ARD, pp 142– 146.

Associate Professor Paul Myers, general and vascular surgeon

A/Prof Myers examined the respondent at the request of the appellant on 3 May 2016 and provided a report of the same date.[22] He advised that he had taken only a brief history of the injury because he was asked to only make an assessment of the WPI of the respondent’s neck and left and right shoulders. The history recorded by A/Prof Myers referred to the previous left shoulder injury, following which the respondent returned to pre-injury duties. A/Prof Myers noted that in June 2007, the respondent tripped and fell, injuring his left knee, left shoulder and nose. The respondent consulted a doctor in Charlestown and investigations showed soft tissue injuries to the neck, left shoulder and knee. A/Prof Myers noted that the respondent experienced increasing problems with his left shoulder over time and developed symptoms in his right shoulder, which the respondent attributed to the nature of the work he was performing. A/Prof Myers discussed the shoulder pathology and treatment. A/Prof Myers also mentioned ongoing and increasing neck pain.
[22] Reply, pp 24–32.
A/Prof Myers performed an upper body examination and reviewed the radiology of the cervical spine, lumbar and thoracic spine and both shoulders. A/Prof Myers provided a WPI assessment of both shoulders and the cervical spine.
A/Prof Myers was asked by the appellant to provide a supplementary report on the basis that the respondent had now made a claim in respect of the left knee. A/Prof Myers responded on 4 May 2017.[23] A/Prof Myers referred to the “documentary evidence” which referred to the respondent having apparently fallen down a flight of stairs in June 2007 and claimed injuries to “the face, nose, head, right shoulder, neck and left knee.”
[23] Reply, pp 33–36.
A/Prof Myers noted:
(a)    the medical certificate referred to a soft tissue injury and only bruising on the left knee;
(b)     an x-ray taken two days after the incident indicated there was no bony injury;
(c)    the x-ray report did not comment on any arthritic changes in the knee at that time;
(d)    the respondent underwent bilateral knee replacements on 22 June 2015, and
(e)    A/Prof Kleinman had subsequently assessed the respondent as having a “fair result” from the surgery and assessed a 20% WPI.
A/Prof Myers remarked that he had not examined the respondent’s knee replacements and was therefore not in a position to either agree or take issue with A/Prof Kleinman’s assessment. In response to specific questions put to him by the appellant, A/Prof Myers advised that:
(a)    he had no evidence of significant degenerative changes of the knee being present in June 2007;
(b)    the fall would not have caused aggravation of degenerative change to the extent that the respondent would require a total knee replacement, and
(c)    the fact that the respondent underwent a right knee replacement at the same time as the left knee was evidence that the left knee would have come to replacement at that time regardless of the fall.
A/Prof Myers commented that he had not examined or taken a history of the respondent’s left knee so that he was not able to make his own assessment of the WPI in respect of it. He observed that:
(a)    as far as he was aware, there was no evidence that the respondent had pre-existing degenerative change that would have been aggravated by the respondent’s work duties;
(b)    knee replacements were commonplace and the vast majority of them were not work caused matters, and
(c)    as far as he was aware, the nature and conditions of employment have not been proven to cause degenerative knee conditions.
A/Prof Myers concluded that the whole of the respondent’s WPI in respect of the left knee should be deducted as none of the impairment was work related.
A/Prof Myers was then provided with a copy of the clinical notes from the respondent’s general practitioners. In a response dated 30 May 2017,[24] A/Prof Myers reviewed the various entries and noted that there was an absence of knee complaints between 2007 and at least 2012. He further noted that he had no specific detail of the alleged injury and said that he therefore had no knowledge of whether the respondent did or did not have a fall and injury in June 2007. Further, he had no information that the respondent had a left knee injury on that date and could only relate what he found on examination in the one and only examination he had performed and what was reported in the radiological investigations. A/Prof Myers advised that he had not examined the respondent in respect of the knees and consequently his view had not changed from his previous reports.
[24] Reply, pp 37–40.
The appellant arranged for A/Prof Myers to examine the respondent for a second time on 16 January 2018. A/Prof Myers provided a report on that date.[25] A/Prof Myers provided a brief history of his experience and expertise, indicating that he had extensively practised in general and vascular surgery and had extensive experience in general and trauma surgery. He advised that since 2001, he had concentrated on vascular surgery.
[25] Reply, pp 41–49.
A/Prof Myers recorded his findings on examination of the cervical spine, and the upper and lower extremities and noted the respondent’s complaints. A/Prof Myers confirmed his opinion that the fall onto the left knee in 2007 was a soft tissue injury only. A/Prof Myers referred to the opinion of A/Prof Kleinman that the injury in 2007 aggravated degenerative change in the left knee and led to the need for the knee replacement. A/Prof Myers said that the opinion that the relatively mild fall onto the knee with no fracture and no other damage would lead to a knee replacement was medically unsustainable. A/Prof Myers confirmed his opinion that the issues with respect to the respondent’s left knee were not related to the respondent’s employment.
At the request of the appellant, in a supplementary report dated 7 February 2018, A/Prof Myers yet again confirmed his earlier opinion in respect of causation and the WPI assessment.[26]
[26] Reply, pp 50–52.
A/Prof Myers again examined the respondent and provided a report dated 9 October 2018.[27] A/Prof Myers took the additional history that the respondent complained of having to rely more on his right knee because of left knee symptoms, and, as a result, he experienced worsening symptoms in his right knee from about six months after the 2007 fall. The respondent complained of symptoms, especially when working or walking on concrete or going up and down a significant number of stairs while carrying weights. A/Prof Myers reiterated that:
(a)    The respondent may have suffered a minor injury to the left knee in 2007;
(b)    any aggravation had long since ceased;
(c)    there was no acceleration, exacerbation or deterioration of pre-existing changes in the left knee;
(d)    there was no body of scientific evidence to support the assertion that work could cause degenerative changes, and
(e)    the onset of complaints and of degenerative changes as people age were caused by physical activities.
[27] Reply, pp 53–65.
A/Prof Myers added that the soft tissue injury to the left knee in June 2007 was on the background of significant degenerative change in the left knee.

THE ARBITRATOR’S REASONS

The Arbitrator noted the injuries and conditions relied on by the respondent in these proceedings consisted of:
(a)    claims for WPI in respect of the cervical spine, both shoulders and left knee as a result of injury on 26 June 2007;
(b)    the claim for the consequential gastrointestinal condition, and
(c)    the further alleged injury in the form of an aggravation of a degenerative disease in the left and right knees with a deemed date of injury of 30 June 2013.
The Arbitrator noted that the appellant’s “principle” concern was the alleged left knee injury on 26 June 2007 and if there was such an injury, it was a muscular injury which had resolved.
The Arbitrator noted the submissions of the parties.
The Arbitrator considered that it was clear that the respondent suffered left knee pain after his fall in 2007. The Arbitrator accepted the respondent’s submission that it was not necessary to identify the precise nature of the pathology in the left knee. The Arbitrator noted the appellant’s submission that by 4 July 2007, any left knee symptoms had resolved and observed that that was not necessarily evidence that there had been no injury to the left knee. The Arbitrator referred to the x-ray report dated 28 June 2007 which disclosed no bony injury and remarked that that did not necessarily preclude some other non-bony injury such as aggravation of previously asymptomatic pathology, as proposed by A/Prof Kleinman.
The Arbitrator formed the view that he preferred the opinion of A/Prof Kleinman, who was an orthopaedic specialist, to that of A/Prof Myers as the injuries were orthopaedic in nature. He accepted that a fall of 1.4 metres was not “minor” as suggested by A/Prof Myers. The Arbitrator considered that to the extent that such a description impacted A/Prof Myer’s opinion, the opinion was rejected.
The Arbitrator was of the view that the respondent’s description of his duties was not seriously challenged by the appellant and on that basis, the Arbitrator accepted that the duties were as described. He accepted A/Prof Kleinman’s reliance on that description.
The Arbitrator found that, on the basis of the available evidence:
(a) on 26 June 2007, the respondent suffered injury to his cervical spine, both upper extremities, the left lower extremity and a consequential gastrointestinal condition in accordance with s 4(a) of the 1987 Act, and
(b) as a result of the nature and extent of his duties between 26 June 2007 and 30 June 2013, the respondent sustained injury to his right lower extremity (knee) by way of aggravation or acceleration of a disease in accordance with s 4(b)(ii) of the 1987 Act to which employment was the main contributing factor.
The Arbitrator’s Certificate of Determination issued on 10 December 2019 is recorded at [4] above.

GROUNDS OF APPEAL

The appellant appeals the Arbitrator’s findings in relation to the left and right knees. The appeal grounds are expressed as follows:
“1. With respect to the left knee:
(a)The Appellant alleges that the Arbitrator made an error of mixed fact and law by failing to determine the question of injury with respect to the left knee in accordance with the requirements of s 4 of the Workers Compensation Act [1987].
(b)The Appellant alleges that the Arbitrator made an error of law by declining to determine the nature of the injury sustained by the worker to his left knee and failing to make findings with respect to a nature and conditions claim in relation to the left knee.
(c)The Appellant alleges that the Arbitrator made an error of fact by rejecting the opinion of Dr Myers on the basis that the opinion of Dr Myers was based on thinking that the worker had sustained a ‘minor fall’.
2. With respect to the right knee - The Appellant alleges that the Arbitrator made an error of law by failing to apply the requirements of s 4(b)(ii) and accepting the opinion of Dr Kleinman, as a basis for finding that the worker had suffered an injury to his right knee.”

LEGISLATION

Section 4 of the 1987 Act relevantly defines injury as:
“Definition of ‘injury’
In this Act:
injury
(a) means personal injury arising out of or in the course of employment,
(b) includes a disease injury, which means:
(i) a disease that is contracted by a worker in the course of employment but only if the employment was the main contributing factor to contracting the disease, and
(ii) the aggravation, acceleration, exacerbation or deterioration in the course of employment of any disease, but only if the employment was the main contributing factor to the aggravation, acceleration, exacerbation or deterioration of the disease, and
…”

SUBMISSIONS

Ground 1(a): the Arbitrator made an error of mixed fact and law by failing to determine the question of injury with respect to the left knee in accordance with the requirements of s 4 of the 1987 Act

The appellant’s submissions

The appellant refers to the definition of injury found in s 4 of the 1987 Act and refers to McColl JA’s observation in Tudor Capital Australia Pty Limited v Christensen[28] that what is required is a “precise consideration on a fact by fact basis of the evidence” and the identification of a “physiological change or disturbance of [the respondent’s] normal physiological state.”[29] The appellant submits that in contrast, the Arbitrator said that:
“It is clear that [the respondent] suffered left knee pain after his fall. I accept Mr Levick’s submission that it is unnecessary for the Commission to determine the precise nature of the pathology.”[30]
[28] [2017] NSWCA 260 (Christensen).
[29] Christensen, [339].
[30] Melksham v Dywidag Systems International Pty Ltd 5332/19, 10 December 2019 (reasons), [33].
The appellant submits that the Arbitrator’s “bare assertion” of left knee pain resulting from the fall in 2007 was sufficient to establish injury is not consistent with McColl JA’s observation in Christensen that s 4 of the 1987 Act requires a physiological change or disturbance of the appellant’s normal state.
The appellant asserts that it cannot be said that the Arbitrator’s reasoning disclosed a “fact by fact” evaluation of the evidence. The appellant says that the Arbitrator’s finding that there was an aggravation of previously asymptomatic pathology fails to take into account the facts before him, in particular that there was no medical evidence of injury to the right knee following the fall in 2007. Nor did the Arbitrator take into account that there was a five year gap between the fall and the onset of complaints in the left knee.
The appellant submits that the Arbitrator was required to undertake an analysis of the evidence before determining the physiological change which was causative of injury to the left knee, in accordance with Christensen. The appellant asserts that there was no evidence as to what the physiological change was and so the finding of injury to the left knee was not available to the Arbitrator. The appellant contends that the Arbitrator’s reasons in finding an injury pursuant to s 4 were deficient because of his failure to apply Christensen which led the Arbitrator to incorrect factual conclusions, revealing error of fact and law.

The respondent’s submissions

The respondent submits that the appellant’s notice disputing liability dated 3 May 2018 issued pursuant to s 74 of the 1998 Act (the s 74 notice) indicated that the appellant disputed liability for the left knee on the following bases:
(a)    the left knee injury on 26 June 2007 was only a “soft tissue” injury;
(b)    the x-ray dated 28 June 2007 indicated no injury to the bone, and
(c)    on the basis of the opinion of A/Prof Myers, the respondent did not suffer an aggravation of degenerative changes in the left knee in the 2007 fall.
The respondent says that there was, therefore, no dispute that the respondent suffered an injury to his left knee on 26 June 2007. The respondent referred to the Commission’s bifurcated system for determination of lump sum compensation pursuant to s 66 of the 1987 Act. The appellant cites Jaffarie v Quality Castings Pty Ltd,[31] in particular at [247], where Roche DP cited the Court of Appeal decision in Bindah vCarter Holt Harvey Wood Products Australia Pty Ltd,[32] in which Emmett JA said:
“[T]he arbitrator did not need to make a determination about the precise nature of the injury, because that matter fell within the province of a medical dispute, which was for the approved medical specialist, and, if necessary, the Appeal Panel, to determine. The arbitrator’s determination that Mr Bindah had suffered an injury meant that he had suffered an injury according to the definition of that term in s 4 of the Compensation Act. That definition includes both a personal injury and an aggravation, acceleration, exacerbation or deterioration of a disease. It was then for the approved medical specialist to determine the degree of permanent impairment that resulted from the injury. That determination involved a conclusion on a matter of causation, as indicated by the words in bold.”[33] (emphasis included in original)
[31] [2014] NSWWCCPD 79 (Jaffarie).
[32] [2014] NSWCA 264 (Bindah).
[33] Bindah, [119].
The respondent further refers to the observations of Snell DP in Inghams Enterprises Pty Ltd v Belokoski[34] that the Commission has jurisdiction to determine whether a worker suffered an injury and the nature of the injury and whether it is necessary or desirable to make specific findings about the pathology will depend on the circumstances and the evidence in each case.
[34] [2017] NSWWCCPD 15 (Belokoski).
The respondent also relies on Kempsey Shire Council v Kirkman,[35] in which Roche DP observed:
“Though it will often be preferable, it is not essential, as a matter of law, that the Commission determines the precise nature of the injury received by a worker. What is required is a finding that the worker received an injury arising out of, or in the course of, his or her employment, and that employment was a substantial contributing factor to that injury.”[36]
[35] [2010] NSWWCCPD 104 (Kirkman).
[36] Kirkman, [82].
The respondent says that the appellant’s case at arbitration was essentially that the appellant’s left knee injury in 2007 had resolved, as noted by the Arbitrator at [24] of his reasons. The appellant submits that in relation to the question of whether the respondent suffered injury to his left knee in the fall in 2007, the following material evidence is relevant:
(a)    the respondent’s evidence that he fell 1.4 metres, striking his left knee was unchallenged;
(b)    the claim form completed by the respondent on 28 June 2007 reported the body parts injured in fall as the face, nose, head, right shoulder, neck and left knee;
(c)    on 28 June 2007, the respondent attended Dr Mills, who noted anterior left knee pain which was worse with bending the knee when weight bearing and swelling and bruising below the patella, and
(d)    the left knee was x-rayed on 28 June 2007.
The respondent submits that the appellant’s submission that the Arbitrator’s “bare assertion” of left knee pain as a result of the fall was not sufficient to found injury ignores that evidence. The respondent further submits that, as recorded by the Arbitrator at [24] of his reasons, the appellant conceded at arbitration that the contemporaneous evidence supported a complaint of pain at the time of the injury, but submitted that the clinical note dated 4 July 2007 indicated the pain had settled. The respondent points out that this was conceded in the s 74 notice dated 3 May 2018.
The respondent submits that on the basis of the above, the finding of injury to the left knee was undoubtedly correct.
The respondent further submits that, although in accordance with Belokoski the Arbitrator was not required to determine the pathology arising from the injury, (which the respondent says was his submission to the Arbitrator), the Arbitrator dealt with that issue in his reasons where he determined that while there was no bony injury, that did not preclude the finding that there was a non-bony injury, as in an aggravation of previously asymptomatic pathology.
The respondent asserts that Christensen is factually different to this case and can be distinguished. The respondent says that the issue in Christensen was the causation of the ventricular fibrillation causing cardiac arrest and its relationship to the employment, whereas in the present case, the issue is whether the respondent suffered injury to his left knee and whether a permanent impairment flowed from that injury. The respondent asserts that the appellant is conflating those two issues.
The respondent contends that, because the evidence clearly showed the respondent had suffered an injury in the fall, the ultimate question to be determined was whether or not the injury resulted in a permanent impairment, which was a question for the AMS, as was the case in Haroun v Rail Corporation of New South Wales.[37]
[37] [2008] NSWCA 192; 7 DDCR 139 (Haroun).

The respondent submits that it is irrelevant that the aggravation may have ceased, but in any event, the Arbitrator implicitly dealt with that question when he rejected the opinion of A/Prof Myers and accepted that of A/Prof Kleinman, which was a finding that was available to him on the evidence.
The respondent concludes that there was no error of the kind required to interfere with the Arbitrator’s findings on this point.

Ground 1(b): the Arbitrator erred in law by declining to determine the nature of the injury to the left knee and failing to make findings with respect to a nature and conditions claim in relation to the left knee

The appellant’s submissions

The appellant says that the power of the Commission to determine the nature of the injury was extensively discussed by Roche DP. The appellant does not nominate the case upon which it relies, but it is apparent that the appellant is referring to Jaffarie. The appellant cites the following passage, in which Roche DP discussed Emmett JA’s observations in Bindah:
“The absence of any similar provisions for ‘the nature of the injury’ points strongly to the conclusion that ‘the nature of the injury’ is a matter for the Commission to determine. This is consistent with Emmett JA’s statement at [111] that it is for the Commission ‘to determine whether a worker has suffered an injury within the meaning of s 4 of the [1987] Act’ and his Honour’s later statement (at [118]) that only ‘certain matters of causation’ (emphasis added) are within the exclusive jurisdiction of an AMS.”[38]
[38] Jaffarie, [257].
The appellant submits that the nature of the respondent’s left knee condition has been persistently raised as an issue in dispute in various notices issued pursuant to s 74 of the 1998 Act. The appellant says that it only accepted that the respondent suffered a strain in the injury on 26 June 2007. The appellant asserts that at all times it disputed that there was evidence that the respondent suffered an aggravation of degenerative changes in the left knee in that incident. The appellant contends that, given that the nature of the injury was in issue, the Arbitrator’s observation that it was unnecessary to determine the precise pathology was contrary to the proposition in Jaffarie, and therefore an error of law.
The appellant says that the Arbitrator failed to make any finding in respect of the allegation of injury to the left knee as a result of the nature and conditions of the respondent’s employment, an allegation which the appellant had disputed. The appellant submits that the failure materially impacts the outcome of the case because if the allegation was made out, the left knee would have been referred to the AMS for assessment on a different basis. The appellant submits that this is an error of law.

The respondent’s submissions

The respondent adopts his submissions already made in respect of the necessity to make findings as to the pathology in the left knee. The respondent submits that the Arbitrator accepted that the respondent suffered injury to his left knee on 26 June 2007, and that was the injury which was referred to the AMS. The respondent asserts that the appellant’s complaint that the left knee was only referred to the AMS in respect of the injury on 26 June 2007 has no basis. The respondent points out that the Arbitrator made no finding that any pathology in the left knee had been contributed to by the nature and conditions of the respondent’s employment after 2007.
The respondent says that if the appellant’s complaint is that the Arbitrator failed to make a finding as to whether the respondent suffered an aggravation, acceleration, exacerbation or deterioration of underlying osteoarthritis then that would be a matter about which the respondent would appeal. The respondent asserts that the Arbitrator’s findings speak for themselves, and there has been no appeal in respect of the failure to determine this issue. The respondent submits that the AMS must assess the degree of permanent impairment that results from the injury to the left lower extremity on 26 June 2007, which the Arbitrator found was an aggravation of a disease, namely osteoarthritis.

Ground 1(c): the Arbitrator made an error of fact by rejecting the opinion of A/Prof Myers on the basis that the opinion of A/Prof Myers was based on thinking that the worker had sustained a “minor fall”

The appellant’s submissions

The appellant submits that the Arbitrator has mischaracterised A/Prof Myers’s opinion in that A/Prof Myers frequently referred to the fall but did not describe it as “minor.” Further, A/Prof Myers did not base his opinion on that comment. The appellant submits that A/Prof Myers stated:
(a) the injury to the left knee and the symptoms arising out of the injury were minor, and
(b) there was no evidence that the fall caused an actual injury other than a minor soft tissue injury.
The appellant submits that in all of the reports of A/Prof Kleinman, he specifically noted that the respondent did not take any time off work after the fall. The appellant asserts that it is apparent that the injury to the knee was not as a result of the fall but resulted from a twisting movement and is best described as a “glancing blow.”
The appellant contends, therefore, that the Arbitrator has misstated the actual injury to the respondent’s left knee and A/Prof Myers’s opinion as to the seriousness of the left knee injury, which is a factual error in the Arbitrator’s reasons.

The respondent’s submissions

The respondent refers to the Arbitrator’s preference for the opinion of A/Prof Kleinman over that of A/Prof Myers on the basis that A/Prof Myers was a vascular surgeon and not an orthopaedic surgeon. The respondent cites the passage from A/Prof Myers’s report where he describes his experience in general trauma surgery but mainly in the area of vascular medicine and submits that it was open to the Arbitrator to take that into account.
The respondent points out that A/Prof Myers examined the respondent on three occasions. In his report dated 3 May 2016, A/Prof Myers took only a brief history because he was asked to restrict his assessment to an assessment of the neck and shoulders and made no reference to the left knee. Notwithstanding the absence of any reference to the left knee, and without a re-examination of the respondent, A/Prof Myers proffered an opinion in relation to the left knee pathology and its causation in the subsequent report dated 4 May 2017. The respondent says that A/Prof Myers, again without the benefit of an examination of the respondent, reported dated 30 May 2017 that:
(a)    he had no way of knowing whether the respondent did or did not have a fall on 26 June 2007;
(b)    he did not take a history of injury to the knees, and
(c)    his opinion remained unchanged from his previous reports.
The respondent submits that A/Prof Myers took no history of the nature of the fall and does not explain how his conclusion was that the fall was “mild.” Further there was no evidence that the injury was a “glancing blow” as described by the appellant and the respondent’s evidence was that he struck his knee on concrete. The respondent refers to his evidence that he had no symptoms in either knee before 2007, and that after June 2007, his left knee never settled. The respondent submits that it was open to the Arbitrator to conclude that the blow to the left knee was not mild, as described by A/Prof Myers.
The respondent observes that A/Prof Myers reviewed the respondent on 9 October 2018 and took no further history of injury or any complaint by the respondent of ongoing symptoms in the knees.
The respondent submits that in the light of the above deficiencies in the reports of A/Prof Myers, it was open to the Arbitrator to accept the opinion of A/Prof Kleinman over that of A/Prof Myers, despite the brief manner in which the Arbitrator arrived at that conclusion.
The respondent submits that there is no reason for appellate intervention in respect of the Arbitrator’s conclusion.

Ground 2: the Arbitrator erred by failing to apply the requirements of s 4(b)(ii) and accepting the opinion of Dr Kleinman, as a basis for finding that the worker had suffered an injury to his right knee.

The appellant’s submissions

The appellant refers to the definition of injury in s 4(b)(ii) and the Arbitrator’s reasons for finding in the respondent’s favour on that issue, which were:
“The applicant’s statements concerning the nature and extent of his duties up until he was made redundant on 30 June 2013 are not seriously contested by any evidence offered by the respondent. I therefore accept his description of duties and accept Dr Kleinman’s reliance on that description in forming his conclusion.”[39]
[39] Reasons, [36].
The appellant submits that A/Prof Kleinman provided no opinion in respect of whether the respondent suffered an injury in accordance with s 4(b)(ii) of the 1987 Act or whether employment was the main contributing factor to the injury. The appellant submits that A/Prof Kleinman’s opinion only went so far as to say that the respondent’s employment “could have” aggravated his employment. The appellant says that falls short of what is required to establish a s 4(b)(ii) injury and is silent as to whether the respondent’s employment was the main contributing factor to the aggravation of the right knee.
The appellant remarks that if s 4(b)(ii) was properly applied, the respondent must have suffered a serious deterioration of his right knee during 2014 and 2015, which was after he ceased work.
The appellant concludes that A/Prof Kleinman’s opinion was not sufficient to establish that the respondent suffered injury to the right knee in accordance with s 4(b)(ii) and that the Arbitrator failed to apply the “main contributing factor” test as required by that section, which was an error of law.

The respondent’s submissions

The respondent submits that it was open to the Arbitrator to find that the respondent injured his right knee. The respondent refers to the description of the nature of his duties provided in his statement which placed strain and stress on both knees. The respondent also quotes from the reports of A/Prof Kleinman in which A/Prof Kleinman considered that the nature and conditions of the respondent’s employment would have:
(a) aggravated and accelerated the osteoarthritic changes in the left knee which were significantly aggravated by the fall, and
(b) involved work that could have aggravated the pre-existing degenerative changes in the right knee.
The respondent asserts that the word “could” does not preclude a finding that the nature of the respondent’s work was the main contributing factor to the aggravation of the underlying disease, which is a factual conclusion to be reached on the basis of the evidence. The respondent refers to Adelaide Stevedoring Co Ltd v Forst[40] as authority for the proposition that “if medical science is prepared to say that something is possible, a Judge on examining the lay evidence may decide that it is probable.”[41]
[40] [1940] HCA 45; 64 CLR 538.
[41] Respondent’s submissions, [66].
The respondent says that the Arbitrator had before him the unchallenged evidence of the respondent as to the heavy nature of the work performed by him and had the benefit of A/Prof Kleinman’s opinion. The respondent refers to A/Prof Kleinman’s opinion that the work could have aggravated or accelerated the underlying condition and assessed the respondent as suffering from 18% WPI as a result of the right knee condition, which was as a result of the nature and conditions of employment. The respondent submits that it is implicit in that assessment that, not only could the work have aggravated the condition, it did, and that employment was the main contributing factor to the impairment which is a relevant consideration to the question of causation.
The respondent points out that the only contrary evidence was that of A/Prof Myers. The respondent submits that A/Prof Myers effectively dismissed that there was a medical possibility that the nature of the work performed by the respondent could cause degenerative change. The respondent explains that for an “aggravation” to be found, it is not necessary to show that there was an actual worsening of the condition itself, it is enough to show that there was an increase in symptoms and restrictions. The respondent refers to Rural Press Limited v Hancock[42] and Federal Broom Co Pty Ltd v Semlitch[43] as authorities to support that submission.
[42] [2009] NSWWCCPD 160, [67].
[43] [1964] HCA 34; 110 CLR 626.
The respondent submits that A/Prof Myers appears to accept that the “heavier” nature of the respondent’s work would cause symptoms and the respondent gave evidence of increasing pain while performing that work. The respondent says that the combination of the evidence of the nature of the work and the deteriorating condition, the opinion of A/Prof Kleinman and the concession by A/Prof Myers provided an evidentiary basis for the Arbitrator’s finding.
The respondent submits that the finding on causation is a finding of fact and the Arbitrator adopted a common sense approach as described in Kooragang Cement Pty Ltd v Bates.[44] The respondent further submits that to the extent that the factual question required the employment to be the main contributing factor to the aggravation, there was no evidence of any other aggravating factor.
[44] (1994) 35 NSWLR 452; 10 NSWCCR 796.
The respondent submits that although the Arbitrator’s reasons were brief, the ultimate finding was clearly available on the evidence.

THE RELIEF SOUGHT

The appellant seeks awards in its favour in respect of the allegation of injury in the form of aggravation of the degenerative changes in the left knee and in respect of the allegation of injury as a result of the nature and conditions of employment.
The respondent seeks to have the matter referred for determination by another arbitrator in the event that the appeal succeeds.

CONSIDERATION

Ground 1(a): the Arbitrator made an error of mixed fact and law by failing to determine the question of injury with respect to the left knee in accordance with the requirements of s 4 of the 1987 Act, and

In essence, the matters complained about by the appellant and the submissions of the parties made in this appeal jointly address both Ground 1(a) and Ground 1(b). It is therefore convenient to consider both Grounds together.
In their submissions, the parties refer to various authorities to support their respective positions. The appellant relies on Christensen. The respondent refers to Bindah, Jaffarie, Kirkman and Belokoski. Each of those decisions should be considered in the light of their facts and the issues to be determined.
As pointed out by the respondent, Roche DP observed in Kirkman that as a matter of law, it is not necessary for the Commission to determine the precise nature of the injury, but it is preferable.[45] Roche DP also observed that:
“The real issue in this case is whether Mr Kirkmanhas the symptoms of which he complains and whether those symptoms have resulted from the injury on 20 June 2006 and/or treatment provided for that injury. That is a causation issue which requires the application of the commonsense test of causation discussed in Kooragang Cement Pty Ltd v Bates …”.[46]
And
“The question is whether the symptoms have, as a matter of commonsense, resulted from the injury”.[47]
[45] Kirkman, [82].
[46] Kirkman, [78].
[47] Kirkman, [97].
In Kirkman, Roche DP was conducting a review of the merits of the matter (as he was required to do in accordance with the former s 352 of the 1998 Act), and determined that in the circumstances of that case, it was not relevant to an evaluation of the causation issue as to whether Mr Kirkman suffered from a neurological condition or an inguinal hernia. I do not accept that the facts in Kirkman are consistent with the facts in this case, where the nature of the injury was a very relevant issue. As Snell DP observed in Belokoski, whether it is necessary for the Commission to make specific findings as to the nature of the injury will depend on the circumstances and the evidence in each case.[48]
[48] Belokoski, [222].
The Court of Appeal decision in Bindah was discussed at length by Roche DP in Jaffarie. Roche DP referred in particular to the passage from the judgment of Emmett JA cited by the respondent at [79] above in which Emmett JA observed that certain matters were within the exclusive jurisdiction of the AMS. Following a consideration of the judgments of both Meagher JA and Emmett JA, Roche DP provided the following useful summary of the principles relevant to the issue in this case enunciated in Bindah:
“This means that … in a claim for lump sum compensation, the physical consequences of the injury (in relation to the assessment of whole person impairment as a result of the injury) are not within the exclusive jurisdiction of the Commission. They are within the exclusive jurisdiction of the AMS. That is so even if the matter also involves a disputed claim for weekly compensation and disputes about causation, which the Commission has determined.
However, it is accepted, as Emmett JA expressly acknowledged (at [111]), that it is for the Commission to determine whether a worker has received an injury within the meaning of s 4 of the 1987 Act (the one exception to this statement relates to loss of hearing claims, discussed below). It is also accepted, though it was not expressly considered in Bindah, that ‘injury’ in s 4 includes an injurious event and the pathology caused by that event.”[49]
[49] Jaffarie, [250]–[251].
Deputy President Roche added that:
“In other words, an ‘incident’ (an injurious event) is only a mechanism for suffering an injury and is not itself a s 4 injury. The relevant ‘injury’ in s 4 is the pathology that has arisen out of or in the course of the employment. …
To the extent that Emmett JA appears to have suggested (at [119]) that ‘the precise nature of the injury’ is ‘within the province of a medical dispute’, which is for an AMS to determine, I note that the definition of a medical dispute in s 319 [of the 1998 Act] does not include ‘the nature of the injury’, though it does include ‘the worker’s condition’ and the ‘aetiology of the condition’. However, to the extent that the expressions ‘worker’s condition’ and the ‘aetiology of the condition’ relate to ‘the nature of the injury’, it must be remembered that the AMS’s opinion (expressed in a valid MAC) on those matters is not conclusively presumed to be correct.”[50]
[50] Jaffarie, [253]–[254].
Deputy President Roche concluded that:
“The absence of any similar provisions for ‘the nature of the injury’ points strongly to the conclusion that ‘the nature of the injury’ is a matter for the Commission to determine. This is consistent with Emmett JA’s statement at [111] that it is for the Commission ‘to determine whether a worker has suffered an injury within the meaning of s 4 of the [1987] Act’ and his Honour’s later statement (at [118]) that only ‘certain matters of causation’ (emphasis added) are within the exclusive jurisdiction of an AMS.”[51]
[51] Jaffarie, [257].
In the context of a claim brought purely for potential entitlements to lump sum compensation pursuant to s 66 of the 1987 Act in respect of the appellant’s whole person impairment, the Arbitrator clearly did not have jurisdiction to determine whether the injury suffered by the respondent in 2007 had resolved. To the extent that this was an issue presented by the appellant at arbitration, the Arbitrator did not make such a finding.
The appellant asserts that in dealing with the question of “injury” within the meaning of s 4 of the 1987 Act, the Arbitrator was required to identify the pathological change that occurred in the event on 26 June 2007. Noting the respondent’s submission to the Arbitrator recorded at [12] of the Arbitrator’s reasons, the pathological nature of the injury on 26 June 2007 was clearly in issue before him. The Arbitrator accepted the respondent’s submission that it was not necessary for him to determine the pathology arising from that injury. In the circumstances of this case, the nature of the injury was indeed a matter for the Commission to determine. Applying the rationale set out by Roche DP in Jaffarie, the Arbitrator was in error by failing to determine that issue.

The appellant refers to the Arbitrator having made a finding that there was an aggravation of previous asymptomatic pathology in the left knee, which was not founded on the evidence. There was no such finding made by the Arbitrator. The Arbitrator simply observed that:
“The finding of no evidence of bony injury in the x-ray report in 2007 does not preclude a finding that there was other (for example non-bony) injury, namely aggravation of previously asymptomatic pathology in the sense contemplated by Dr Kleinman.”[52]
[52] Reasons, [34].
The respondent submits that the Arbitrator “dealt with” the issue of identification of the pathology in that passage. I do not accept that the Arbitrator’s observation that such a finding is not precluded amounts to a finding that the pathology was in fact an aggravation of a previously asymptomatic condition.
It follows that Grounds 1(a) and 1(b) of this appeal establish error on the part of the Arbitrator.
Further, in respect of Ground 1(a) of the appeal, the appellant submits that the Arbitrator failed to make any finding in respect of the allegation of injury to the left knee as a result of the nature and conditions of employment with a deemed date of 30 June 2013. That observation is indeed correct. Unusually, the respondent has not agitated this failure on the appeal. Nonetheless, the appellant has agitated the point and the failure of the Arbitrator to deal with an issue raised before him is an error and, as long as the issue remains a live issue, must be corrected.

The appellant has identified error on the part of the Arbitrator in respect of his determination in relation to the injury to the left knee occurring on 26 June 2007. It remains that the issue as to the nature of the injury suffered requires a re-determination. The challenge to the Arbitrator’s rejection of the opinion of A/Prof Myers pertains to whether the left knee was injured as alleged, including the nature of the pathology arising in that event. Consequently, the Arbitrator’s reasons and determination in respect of the left knee are to be set aside and require re-determination. The acceptance or otherwise of the medical evidence pertaining to this issue will therefore be a matter for the new decision maker and it is not appropriate for me to express a view about the cogency of that evidence.
It is therefore not necessary or appropriate to determine this ground of appeal.

Ground 2: the Arbitrator erred by failing to apply the requirements of s 4(b)(ii) and accepting the opinion of Dr Kleinman, as a basis for finding that the worker had suffered an injury to his right knee.

The Arbitrator correctly identified that the respondent’s evidence about the nature of the work he performed was not contested by evidence from the respondent. It was therefore open for the Arbitrator to accept that evidence and to consider that it was a proper basis upon which A/Prof Kleinman reached his conclusion on that issue.
The appellant submits that A/Prof Kleinman did not offer an opinion in respect of whether the respondent suffered an injury in accordance with s 4(b)(ii) of the 1987 Act.
In his report dated 31 October 2014, A/Prof Kleinman expressed the opinion that the respondent “most probably also has degenerative changes in his right knee which have been aggravated by the nature and conditions of his work.”[53] In a subsequent report dated 27 June 2018, A/Prof Kleinman described the nature of the respondent’s work duties and concluded that the respondent:
“probably had idiopathic, degenerative changes in his right knee but the nature and conditions of his employment as a carpenter which would have involved hard physical work, climbing up and down ladders and stairs, kneeling and squatting and carrying heavy weights could have aggravated the underlying degenerative change in his right knee.”[54]
[53] ARD, p 113.
[54] ARD, p 145.
A/Prof Kleinman also provided an assessment of 20% WPI in respect of the right lower extremity (knee) of which he attributed 18% WPI to the nature of the work the respondent performed as a carpenter/builder.
In circumstances where evidence is not inherently illogical or implausible, if the Arbitrator makes an apparently rational choice between competing expert evidence, it is very difficult for a disappointed party to complain on appeal that there should have been a different outcome.[55]
[55] Caruana v Darouti [2014] NSWCA 85 per McDougall J (Leeming JA agreeing), [124]
Reading A/Prof Kleinman’s opinion in those reports together, the evidence was not illogical and was probative of the issue for determination. It provided a sufficient and proper basis upon which the Arbitrator could found his conclusion that the respondent had made out his case that the degenerative change in the respondent’s right knee had been aggravated by the nature of the work, in accordance with s 4(b)(ii) of the 1987 Act.
The appellant further asserts that A/Prof Kleinman’s opinion did not support a finding that the respondent’s employment was the main contributing factor to the s 4(b)(ii) aggravation, as required by that section. As the respondent submits, there was no evidence of any other, non-employment, aggravation of the disease process in the respondent’s right knee. On that basis, the Arbitrator’s finding that the employment was the main contributing factor to the aggravation was a matter of commonsense, and no error is disclosed.
It follows that the appeal against the Arbitrator’s decision that the respondent suffered an injury to his right knee in the form of an aggravation or acceleration of the disease in the right knee, to which the respondent’s employment was the main contributing factor, with a deemed date of injury of 30 June 2013, fails.

CONCLUSION

The appellant’s appeal against the decision of the Arbitrator in respect of his failure to determine the issue of the pathological consequences of the incident on 26 June 2007 succeeds. The issue requires determination and, given the absence of a transcript of the submissions made by the parties at arbitration, is to be remitted to another arbitrator for re-determination.
The outstanding issue in respect of whether the respondent’s left knee condition was aggravated or accelerated by the nature and conditions of his employment with a deemed date of injury of 30 June 2013 remains at large. If that allegation is pressed by the respondent, this issue also requires determination.
As a consequence, it is inappropriate to determine whether it was open to the Arbitrator to prefer the opinion of A/Prof Kleinman over that of the A/Prof Myers in respect of the determination of whether the respondent suffered an injury to the left knee on 26 June 2007 in accordance with s 4 of the 1987 Act and/or an injury deemed to have occurred on 30 June 2013, in accordance with s 4(b)(ii) of the 1987 Act.
The appellant’s appeal against the decision of the Arbitrator in respect of the Arbitrator’s finding that the respondent suffered injury to the right knee injury as a result of the nature and conditions of the respondent’s employment in accordance with s 4(b)(ii) of the 1987 Act fails. Accordingly, the Arbitrator’s finding in relation to that issue is confirmed.
It is appropriate that the Arbitrator’s orders remitting the matter to the Registrar for referral to the Approved Medical Specialists for assessment of whole person impairment of the cervical spine, both upper extremities, gastrointestinal condition and the right lower extremity be stayed pending the outcome of the determination of the injuries described in [129] and [130] above.

DECISION

The Arbitrator’s finding that the respondent suffered injury to his right knee in the form of an aggravation or acceleration of a disease in accordance with s 4(b)(ii) of the Workers Compensation Act 1987 as a result of the respondent’s employment between 26 June 2007 and 30 June 2013 to which employment was the main contributing factor is confirmed.
The Arbitrator’s finding that the respondent suffered an injury to his left knee on 26 June 2007 is revoked.
The issues of whether the respondent suffered:
(a) an injury to the left knee (including the nature of the injury) on 26 June 2007, and
(b) an injury to the left knee in the form of an aggravation or acceleration of a disease as a result of the nature and conditions of employment from 26 June 2007 to 30 June 2013
are remitted to a different arbitrator for determination.
The Arbitrator’s orders remitting the matter to the Registrar for referral to the Approved Medical Specialists for assessment of whole person impairment of the cervical spine, both upper extremities, gastrointestinal condition and the right lower extremity are stayed until the outcome of the determination of the injuries to the left knee referred above.

Elizabeth Wood

DEPUTY PRESIDENT

30 June 2020