Ducat and Military Rehabilitation and Compensation Commission (Compensation)

[2021] AATA 613

Ducat and Military Rehabilitation and Compensation Commission (Compensation) [2021] AATA 613 (24 March 2021)

Division:VETERAN’S APPEALS DIVISION

File Number(s):      2020/1424

Re:Robert Ducat

APPLICANT

Military Rehabilitation and Compensation CommissionAnd  

RESPONDENT

DECISION

Tribunal:Dr I Alexander, Senior Member

Date:24 March 2021

Place:Sydney

The decision under review is affirmed.

...................................[sgd]....................................

Dr I Alexander, Senior Member

CATCHWORDS

WORKERS’ COMPENSATION – Undated compensation claim – whether the Applicant’s bilateral knee osteoarthritis was contributed to “in a material degree” by his service in the Australian army – independent expert evidence - decision under review affirmed.

LEGISLATION

Safety, Rehabilitation and Compensation Act (Defence-related Claims Act) 1988 (Cth) ss 4, 5B, 7 and 14

CASES

Comcare v Sahu-Khan [2007] FCA 15

Military Rehabilitation and Compensation Commission v May [2016] 257 CLR 468

SECONDARY MATERIALS

The Federal Court Expert Evidence Practice Note (GPN-EXPT) dated 25 October 2016.

REASONS FOR DECISION

Dr I Alexander, Senior Member

24 March 2021

BACKGROUND

1. Mr Ducat, who is now 88 years old, enlisted in the Army on 30 October 1951 and was discharged on 29 October 1957.

2. On 16 March 2019, Mr Ducat lodged an undated compensation claim form for “bilateral hearing loss, bilateral tinnitus, solar keratosis and bilateral knee osteoarthritis”.

3. On 22 July 2019 pursuant to section 14 of the Safety, Rehabilitation and Compensation Act 1988 (Defence-related Claims Act) 1988 (Cth) (the DRC Act), the Department Of Veteran’s Affairs [DVA] accepted liability for “bilateral hearing loss, tinnitus and solar keratosis” but denied liability for  “bilateral knee osteoarthritis”.

4. In a reviewable decision, dated 4 February 2020, a Review Office affirmed the earlier decision to deny liability for “bilateral knee osteoarthritis” under section 14 of the DRC Act.

5. In these proceedings, Mr Ducat who was represented by a legal aid advocate, seeks review of the reviewable decision.

6. In view of the temporary changes regarding the suspension of face-to-face Tribunal hearings during the COVID-19 pandemic, all the parties attended the hearing by video conference.

   RELEVANT STATUTORY PROVISIONS

7. Section 14 of the DRC Act provides that the Commonwealth is liable to pay compensation in respect of an ‘injury suffered by an employee if the injury results in death, incapacity for work, or impairment’.

8. ‘Injury’ is defined in subsection 5A(1) of the DRC Act to mean:

   (a)       a disease suffered by an employee; or

   (b)       an injury (other than a disease) suffered by an employee, that is a physical or mental injury arising out of, or in the course of, the employee’s employment; or

   (c)       an aggravation of a physical or mental injury (other than a disease) suffered by an employee (whether or not that injury arose out of, or in the course of, the employee’s employment), that is an aggravation that arose out of, or in the course of, that employment;

   but does not include a disease, injury or aggravation suffered as a result of reasonable administrative action taken in a reasonable manner in respect of the employee’s employment. [emphasis added]

9. ‘Disease’ is defined in section 5B of the DRC Act:

   (1)       In this Act:

   disease means:

   (a)         an ailment suffered by an employee; or

   (b)         an aggravation of such an ailment;

   that was contributed to, to a significant degree, by the employee’s employment by the Commonwealth or a licensee.

   (2)       In determining whether an ailment or aggravation was contributed to, to a significant degree, by an employee’s employment by the Commonwealth or a licensee, the following matters may be taken into account:

   (a)         the duration of the employment;

   (b)         the nature of, and particular tasks involved in, the employment;

   (c)         any predisposition of the employee to the ailment or aggravation;

   (d)         any activities of the employee not related to the employment;

   (e)         any other matters affecting the employee’s health.

   This subsection does not limit the matters that may be taken into account.

   (3)       In this Act:

   significant degree means a degree that is substantially more than material.

   ‘Ailment’ is defined in subsection 4(1) of the DRC Act:

   “ailment” means any physical or mental ailment, disorder, defect or morbid condition (whether of sudden onset or gradual development).

10. Section 7(4) of the DRC Act states:

    For the purposes of this Act, an employee shall be taken to have sustained an injury, being a disease, or aggravation of a disease, on the day when:

    (a)the employee first sought medical treatment for the disease, or aggravation: or

    (b)the disease or aggravation resulted in the death of the employee or first resulted in the incapacity for work, or impairment

    ISSUES

11. There is no dispute that Mr Ducat’s “bilateral knee osteoarthritis” is an ailment for the purposes of subsection 4(1) of the DRC Act.

12. Mr Ducat contends that the Commonwealth is liable to pay compensation because his service in the Australian Army contributed to the development of his knee condition. 

13. Prior to 13 April 2007, employees were required to establish that their employment had contributed ‘in a material degree’ to their ailment or the aggravation of their ailment.

14. In April 2007, the legislation was amended and ‘in a material degree’ was replaced by ‘to a significant degree’ which was defined as ‘substantially more than material’.

15. The precise date of clinical onset regarding Mr Ducat’s knee condition is disputed, however, the Respondent accepts, and the Tribunal agrees that Mr Ducat sought medical treatment for “bilateral knee osteoarthritis” prior to 13 April 2013. Therefore, for present purposes, it is agreed that the contribution ‘in a material degree’ test under s 5B of the DRC Act applies.

16. Therefore, the definitive issue for the Tribunal is whether Mr Ducat’s ‘bilateral knee osteoarthritis’ was contributed to “in a material degree” by his service in the Australian army.

    DOCUMENTARY EVIDENCE

    Ms Ducat’s written statements

17. In an undated statement Mr Ducat stated, inter alia, as follows:

    I served in the Army between 1951 and 1957. I completed basic training which involved regular lifting and carrying of heavy pack and weapons. I was then posted to a heavy vehicle workshop at: Liverpool where my duties included carrying toolboxes, fuel jerry cans tyres and vehicle parts. During my deployment as a motor mechanic/recovery operator in Darwin 1953 -1957 I did a great deal of heavy physical labour ……when not working on recoveries I worked on as a heavy vehicle mechanic in the workshop……my work in the army was heavy work every day for six years ……

    I began to notice discomfort in my knees as the years passed. I recall complaining to a doctor about my knees and being told there was nothing that could be done, that it was likely arthritis. This would have been 20 years or so after leaving the army. In 1987 I discussed my knee problem with my treating GP, Dr Bruce Williams who told me it was probably arthritis and nothing could be done until I reached a stage where pain and discomfort became intolerable ……in 2002 Dr Williams referred me for an xray of my knees ….in October 2011 I saw orthopaedic surgeon, Dr Cossetto, who operated on my knees on 24 November 2011.

18. In a statement dated 16 June 2020, Mr Ducat provided a summary of his employment after leaving the army and stated inter alia as follows:

    1958-68: itinerant lifestyle ... grape picking in season. Seeking farm gate employment…service station attendant

    1968-76: Hastings Deering in Darwin … parts interpreter, ordering part to be dispatched to NT and South Pacific

    1976 -1978:    Nowra ... workshop manager in an automotive brake station

    1978-1996: Shoalhaven City Council ...  motor mechanic servicing and running repair on cars

    Oral evidence

19. In his evidence in chief, at the hearing, Mr Ducat stated that he first noticed “a problem with the knees ….. closer to 1968” and was told in the “outpatients……that it was possibly arthritis”.

20. When asked about the difference between his work during his Army service and subsequent civilian work he said that his “Army work was in the Northern Territory in the tropics, muddy conditions ….bog situations. When I came back to civilian life ….although some work was difficult and heavy, it was nothing compared with the sort of work I did in the Army”.

21. During cross examination Mr Ducat agreed that he “didn’t get any damage to his knees” during his Army service.

22. Mr Ducat explained that during basic training he was stationed at Liverpool for about 2 years where he was “working on plant and heavy equipment and trucks, general repairs and maintenance”. For the next four years he was stationed in Darwin where he worked as a mechanic in a workshop with seven men that included three other mechanics.

23. Mr Ducat confirmed that he achieved the honorary rank of corporal and was involved in supervision and training of junior soldiers. However, he emphasised his job was “to look after any recovering of bogged vehicles or vehicles that were damaged and had to be towed”.

24. Mr Ducat told the Tribunal that he left school at the age of 14 and worked fulltime seven days a week as a farmhand on the family dairy farm, until he joined the Army at the age of 18. The work included regular ploughing with a horse.

25. In response to questions about the nature of his employment after leaving the Army, Mr Ducat claimed that most of the work was “not very heavy”.

26. When asked about his symptoms and treatment between 2002 and 2008, he said he could “do nothing about it and it wasn’t till the pain became so great ……sent to a specialist.”

27. When asked about his knee injury June 2008, Mr Ducat said “I honestly don’t remember it”, but did remember having further x-rays and having knee surgery in January 2009. He also agreed that after the surgery his knees stated to progressively get worse.

28. In response to a question from the Tribunal Mr Ducat confirmed that after he left the Army he put on weight of up to 88kgs, and after retiring in 1996, he put on further weight of around 120kgs.

    Dr B Williams - General Practitioner (GP)

29. In a medical certificate dated 9 July 2019, Dr Williams stated as follows:

    This is to certify that I confirmed Mr Ducat to be suffering from bilateral knee osteoarthritis sometime in the period not long after my first consultation with him circa 1987. He attended on numerous occasions since then for treatment of the same eventually undergoing bilateral knee arthroplasties……   Unfortunately, the practice went paperless around the year 2000 and after 2007 all existing paper records were destroyed.

    All I can say is that to the best of my knowledge the condition was already chronic at the time we first met in 1987. It is highly probable that various activities during his military service contributed or aggravated the condition.

    Service records, especially from decades past, can be notoriously brief and fail to properly describe a person’s medical conditions.

30. Extracts from Dr Williams Practice Records from 2000 to 2020 with emphasis added:

    ·11.01.2000 – 21.06.2001: 8 consultations with no reference to any knee symptoms.

    ·20.06.2002: returned from 12mth round Aust trip. No major problems

    ·8.10.2002: bilateral knee. prob osteoarthritis. No clicking, locking or giving way …..weight 97 kg  BMI 34.4[1]

    [1] BMI: body mass index – 18.5-24-9 (healthy); 25-29.9 (overweight); 30 and over (obese)

    ·15.10.2002: follow up xrays early osteoarthritis

    ·12.11.2002 – 19.12.2003: 13 consultations with no reference to any knee symptoms

    ·23.12.2003: check-up prior to round Australia trip[2]

    [2] no reference to any knee symptoms

    ·2.03.2004- 28.02.2007: 21 consultations with no reference to any knee symptoms

    ·7.03.2007: review xrays feet. multiple sites of osteoarthritis in the 1^st MTPJs. Mid foot and rear foot bilaterally

    ·18.4.2007 – 9.04.2008: 10 consultations with no reference to any knee symptoms

    ·10.6.2008 – Reason for visit: hypertension - imaging request printed: Plain X-ray – Both Knees (Osteoarthritis)

    ·19.08 2008: – Reason for visit: Dry eyes - right knee medial pain consistent with medial collateral ligament tear 

    ·26.11.2008: Reason for visit-Hyperlipidaemia – knee injury June this year. Tripped with valgus strain right knee. Searing pain medially. Moderate amount of immediate swelling. Pain persisted and got worse, pain during the night …….Xrays show moderate degenerative changes and loose bodies …..orthopaedic review

    ·10.12.2008: Dr Cossetto wants to do knee surgery

    ·4.08.2009: Reason for visit: Bilateral osteoarthritis of the knee

    ·28.10.2010: X-ray report …. There is degenerative osteoarthritis at both knee joints with osteophyte formation

    ·16.11.2010: Follow up xray both knees; bilateral medial compartment osteoarthritis…. likely candidate for bilateral hemiarthroplasties 

    ·9.11.2011: Proceeding with bilateral total knee replacement

31. In a referral letter to Dr Cossetto, dated 26 November 2008, Dr Williams wrote, inter alia, as follows:

    Thank you for seeing Mr Ducat, age 75 years regarding right knee pain and limited range of motion …….knee injury June this year, tripped with valgus strain right knee, searing pain medially…….pain persisted and got worse …..xrays show moderate degenerative changes.

    Service Records

32. Perusal of sixty-one pages of Mr Ducat’s service records revealed no evidence of any complaints or injury with respect to his knees.

33. Mr Ducat’s weight on enlistment is recorded as 142 lb (64.4 kg).

    Dr Cossetto - treating orthopaedic surgeon

34. On 10 December 2008 in his consultation notes Dr Cossetto recorded, inter alia, “75 yo → twisting injury (R) knee ~ 6/12 ago……..O/A R knee  

35. In a letter dated, 10 December 2008, Dr Cossetto stated, inter alia, as follows:

    Robert is a 75 year old man who has had progressively worsening significant right knee discomfort ever since a twisting type injury which occurred 6 months ago …..Xrays (11/6/08) showed very mild osteoarthritic change in each knee joint, curiously worse in the asymptomatic left knee. I have made arrangements for …..an MRI scan as the symptoms could very well be attributable to the presence of a medial meniscal tear and not marked osteoarthritis …… [emphasis added]

36. In a letter dated 12 December 2008, Dr Cossetto noted that an MRI scan of the right knee showed the presence of “posterior horn medial meniscal tear with some developing medial compartment chondromalacia”.

37. In an operation report, dated 13 January 2009, Dr Cossetto noted that arthroscopic examination of the right knee joint revealed “minor patellofemoral degenerative changes with intact articular surfaces …..and degenerative tearing of the inner rim of the lateral meniscus”

38. In a letter, dated 26 November 2010, Dr Cossetto noted that Mr Ducat was “experiencing progressively worsening discomfort in both knees” but was managing well with conservative treatment.

39. In a letter, dated 26 October 2011, Dr Cossetto noted that Mr Ducat was “having increasing pain and dysfunction in both knee joints” and advised that the next step was “bilateral knee arthroplasty”, which was performed on 24 November 2011.

40. In a letter, dated 29 May 2020, Dr Cossetto stated, inter alia, as follows:

    For the purposes of preparing this report I have perused a medical certificate proved by Dr. Bruce Williams, Mr Ducat’s general practitioner, on the 9^th July 2019 and also statements made by Mr Ducat in relation to normal activities undertaken during the course of his enlistment in the Australian Army between 1951 and 1957.

    Dr Bruce Williams in his medical certificate confirms that when he first caught up with Mr Ducat in 1987, the patient was already suffering from symptoms related to bilateral knee osteoarthritis. He advises ……in his opinion the condition was already chronic at the time …..and it was highly probable that various activities during his military service contributed to or aggravated the condition.

    On reviewing the description of work duties undertaken by Mr Ducat for a period of six years as a heavy vehicle mechanic in at times quite muddy and wet questions, with a lot of heavy lifting, in my opinion the years of service in the Royal Australian Army contributed in a material way to the development of bilateral knee osteoarthritis. The likely onset date of his osteoarthritic process would have been in the mid to late 1980s about the time he sought help from his general practitioner …..

    Oral evidence

41. In his evidence in chief, at the hearing, Dr Cossetto stated, inter alia, as follows:

    ….I have a certificate from Dr Bruce Williams, who was Mr Ducat’s GP for many years. And I’ve reviewed Mr Ducat’s statement in particular, recently, and been aware that he was in the Australian Army for six years working as a mechanic looking after heavy vehicles. With the work he would be doing as he’s described in my opinion the knee arthritis would have been contributed to by that employment. There is evidence in the literature that knee osteoarthritis ia attributable to physical loading tasks in the workplace….and in particular with those activities involving heavy lifting and kneeling, there have been a couple of net analyses and they all support that heavy work and knelling activity, stair climbing, kneeling and squatting and heavy lifting can all contribute to the development of knee osteoarthritis.in the workplace. And even European countries such as Denmark and Germany, such knee osteoarthritis is recognized as an occupational disease.

42. In cross examination when asked about what other information he had considered in forming his opinion, Dr Cossetto stated that “his weight was obvious ….And yes that can be a contributing factor to symptoms developing. But on the history of service and when his symptoms developed – yes I was relying on his statement and on the statement of his GP.”

43. When asked to consider the fact that Mr Ducat’s work life spanned approximately 50 years, Dr Cossetto conceded that he was unaware of the physical nature of Mr Ducat’s employment in 44 years when he was not in the Army and conceded that he had only considered his employment in the Army when providing his written report.

44. When asked to clarify the contribution of Mr Ducat’s weight to his knee condition, Dr Cossetto said that “weight can contribute to bringing on symptoms …..but not to the onset.”

45. When asked what else can contribute to osteoarthritis, Dr Cossetto said “It can be many factors. It’s multifactorial. It can be genetics, it can be activity related, sport-related, work -related, trauma. It could be age related”.

46. When asked to consider when he would have expected the osteoarthritis to become symptomatic after the six years of Army service, Dr Cossetto’s’ reply was unconvincing and he simply referred back to Mr Ducat’s statement and the evidence of his GP which suggested symptoms had been present in 1987.

47. When asked about the evidence in the literature he had raised in his evidence in chief, Dr Cossetto said he had not reviewed the relevant articles and was not able to provide any details as to the “extent of those activities” that had to be undertaken to make the connection with osteoarthritis and employment.

48. In response to a question from the Tribunal, Dr Cossetto agreed that osteoarthritis is very common over the age of 65 and said that “It’s very rare to see symptomatic osteoarthritis in a younger age”.

    Dr Gray – Orthopaedic surgeon

49. In a report dated 4 August 2020 Dr Gray stated, inter alia, as follows:

    During his Army career from 1951-1957 Mr Ducat said that he sustained no injury to either knee and recalled no specific knee symptoms despite heavy manual work …..to direct questioning, Mr Ducat recalled no specific injury or symptoms related to either knee in the past. He said that his weight had generally been about 80kgs while in the Army and about 100 kgs while working.; he said that his weight increased to about 124 kgs when he retired and is now about 115kgs.

    Mr Ducat said that he believed that he had some problem with his knee while doing itinerant work after leaving the Army….going up and down on ladders in particular he would feel soreness in his knees and some awkwardness afterwards. However, his history was somewhat vague in terms of time of onset and he was unable to give any specifics with regard to having had any treatment or investigation  ……..In 1987 Mr Ducat said that he attended Dr Williams GP and said that he was told that he had ‘arthritis in the knees’ and that it was too early to do any surgical intervention…. Mr Ducat underwent bilateral knee replacement in 2011[3] ……Mr Ducat was 167cm in height and said he was 115kgs (BMI =41).[4]

    [3] 24 years later.

    [4] Supra at 1

1. After reviewing all the available imaging reports, Mr Ducat’s service records, the relevant GP practice records, Dr Cossetto’s practice records, Dr Williams’ medical certificate, Dr Cossetto’s letter of 29 May 2020 and Mr Ducat’s statements, Dr Gray stated, inter alia, as follows:

   Mr Ducat advised me initially that there had been various times in both the 1970’s and 1980’s where he had spoken to Dr Williams about his knees -however, to direct questioning, Mr Ducat acknowledged that he had not attended Dr Williams in the 1970s.

   Dr Williams entry of 18 October 2002, with no former history of knee injury or medical documentation, in my assessment would reflect the symptomatic onset (clinical onset) of the condition of constitutional bilateral knee osteoarthritis.

   Mr Ducat advised me that he believed he had troubles with his knees that might relate to arthritis while fruit picking and while negotiating ladders…after discharge from the Army, although his history was vague…..he did not convey to me that he had sought medical advice with regard to these before review by Dr Williams in…1987….30 years post discharge …..no documentation available.

   Despite multiple visits to his GP documented after 2000, there was no reference to knee symptoms or history of knee problems or injury by Dr Williams before October 2002; early knee osteoarthritis was documented in 2002.

   Mr Ducat’s current knee diagnosis is: constitutional bilateral knee osteoarthritic/degenerative change - status post bilateral total knee replacements (TKRs) with no obvious complications; clinical situation currently complicated by associated symptomatic spinal stenosis, high BMI and cardiac status.

2. In reviewing Dr Cossetto’s letter, dated 19 February 2019, and noting the pattern of recorded consultations in the practice records of Dr Williams and Dr Cossetto, Dr Gray commented that “the above pattern would fit with the onset of early knee symptoms in about 2002, with his GP initiating X-ray investigations at that stage, reflecting early constitutional knee osteoarthritic/degenerative change. Over a short period of time, there was the fairly rapid period of deterioration in both knees, before requiring total knee replacements in 2011”. [emphasis added]

3. Dr Gray also stated that in his assessment, “heavy work activity over several years in the absence of knee symptoms or injury in a young man of normal weight, would not in any way cause or contribute to the development of bilateral knee arthritis”. [emphasis added]

4. In response to a schedule of questions Dr Gray stated inter alia as follows:

   ·Date of onset of bilateral knee osteoarthritis?- In my opinion, the clinical onset was in 2002, although Dr Williams apparently recalled Mr Ducat having symptoms from 1987; however Dr William’s own multiple clinical entries documented no knee complaints between 2000 and October 2002…..probable early essentially asymptomatic degenerative/osteoarthritic changes would have been present for a  period of about 10 years before 2002.

   ·Aetiology of bilateral knee osteoarthritis? - In my opinion, constitutional in origin; that is, has no specific external cause, apart from Mr Ducat’s own constitutional factors; he would have developed this bilateral condition, with natural deterioration with time, independent of the known factors in the 1950s. Constitutional OA of the knees is a common condition in older Caucasian males. The documented obesity in later adult life would have aggravated any constitutional tendency to knee OA. The symmetrical nature of the OA changes would lend weight to a constitutional cause; a specific unilateral injury would accelerate OA in one knee over the other; some extreme physical factors might cause /accelerate bilateral knee OA – any such factors were not present, from Mr Ducat’s history or documentation. No traumatic cause identified with Mr Ducat.

   ·Did Army service contribute to bilateral knee osteoarthritis? – No cause, contribution or aggravation bilateral knee osteoarthritis by his Army service at any stage because no history of knee symptoms or knee injury during Army service ….symmetrical onset of  degenerative/osteoarthritic changes on x-rays……no documentation of any knee arthritis until 2002, although some allusion to complaints in 1987 that being some thirty years post discharge from the Army.

   ·Any pre-existing or non-work related factors? – Nil specific apart from documented high BMI in later adult years……obesity may accelerate propensity to knee degenerative change. 

   Oral evidence

5. In his evidence in chief, at the hearing, Dr Gray confirmed his opinion that Mr Ducat’s Army service did not cause or materially contribute to his ‘bilateral osteoarthritic knee condition’.

6. Dr Gray said he would diagnose the condition “as what’s generally known as constitutional degenerative osteoarthritic change of both knees. This is common in the Caucasian adult population as you get older.  Both male and female.  Generally, bilateral.  Usually no obvious cause……. originating from the patient himself.  Can be aggravated by… particularly once it is established …. by certain activities…..by obesity….by injury……by  specific trauma.”

7. Dr Gray confirmed that Mr Ducat had said that he during his Army service “apart from heavy work …there was no specific injury to either knee” but noted that there had been some discomfort in the knees “when doing some itinerant work” when he had left the Army.

8. Dr Gray explained that it is generally accepted that heavy or repetitive activity has no effect on normal knees but aggravate already damaged knees with already established arthritic change.

9. Dr Gray indicated that he was aware of the literature mentioned by Dr Cossetto and explained that the American Academy of Orthopaedic Surgeons does specifically outline the physical loading tasks described in those studies “as aggravating symptoms from underlying arthritis……it’s not really a causative situation, it’s merely there are obvious activities that exacerbate symptoms from established arthritis.  There’s no evidence that, without specific injury, that those types of activities cause an initiation of osteoarthritis of the knees.” [emphasis added]

10. Dr Gray stated that, “in the absence of any symptoms at that stage”, the arduous work performed by Mr Ducat during his time in the Army would not have made a material contribution to the onset of his knee osteoarthritis. He added as follows:

    ….In a fit young man, it’s probably advantageous to be active and do physical activity, rather than be a, sort of, couch potato aspect of things. It’s generally accepted, now, in the orthopaedic world, and rheumatological world, that being active and doing heavier, repetitive activities is relatively good for joints, rather than the older concept that, you know, you might damage your joint by overuse of it. ……overuse may pertain once the joint is damaged to a significant degree, but not in the initial  ‑ in a fit patient with normal joints.

    CONSIDERATION

11. There is no dispute that Mr Ducat suffered from severe osteoarthritis of both knees for many years.

12. Mr Ducat contends that there is a causal connection between his Army service and the development of the osteoarthritis.

13. In order to satisfy section 5B of the DRC Act, Mr Ducat submits, that the six years of heavy work during his Army service, contributed to, “in a material degree”, to a “physiological change”[5] in both his knees which, in or about 1987, was diagnosed as “bilateral osteoarthritis” by Dr Williams, his GP.

    [5] Military Rehabilitation and Compensation Commission v May [2016] 257 CLR 468.

14. In the Federal Court’s decision in Comcare v Sahu‑Khan[6] Finn J. considered the meaning of “in material degree” and having regard to the history of the provision, and to the second reading speech for the SRC Act, which in relation to that provision is mirrored in the DRC Act, he concluded:

    I consider that one of the meanings of the word ‘materially’ in the Shorter Oxford English Dictionary probably captures the essence of what the legislature was conveying. And that meaning is: in a material degree, substantially, considerably. [emphasis added]

    [6] Comcare v Sahu-Khan [2007] FCA 15.

15. I consider this to be the ‘evaluative threshold’ that Mr Ducat needs to meet in order to satisfy the Tribunal that his “bilateral osteoarthritis” was caused by his Army service.

16. Mr Ducat relies on the medical certificate, dated 19 July 2019, in which Dr Williams claimed that Mr Ducat was “suffering from bilateral knee osteoarthritis sometime not long after my first consultation with him circa 1987 …..and to the best of my knowledge the condition was already chronic  at the time we first met in 1987”. [emphasis added]

17. The difficulty with Dr Williams’ claim is that it is not supported by any contemporaneous documentary evidence and is not consistent with other evidence before the Tribunal, including his own practice records.

18. The first recorded evidence of any “knee symptoms” was on 8 October 2002 when Mr Ducat was seen by Dr Williams who recorded “bilateral knee pain prob osteoarthritis, no clicking or locking or giving way”.

19. On 9 October 2002 Dr Williams recorded “follow up knee xrays early osteoarthritis”. [emphasis added]

20. The next consultation with respect to Mr Ducat’s “knees” was on 10 June 2008 in the context of an acute injury was to the right knee which in December 2008 was diagnosed by MRI as a “medial meniscal tear”.

21. Dr Williams also expressed the opinion that “It is highly probable that various activities during his military service contributed or aggravated” Mr Ducat’s knee condition. 

22. The difficulty with Dr Williams untested opinion is that he did not provide any reasons to support his opinion and there is no evidence before the Tribunal as to any expertise he has with regard to the epidemiology of knee osteoarthritis.

23. Mr Ducat also relies on Dr Cossetto’s written and oral evidence.

24. In his letter of 29 May 2020, Dr Cossetto expressed the opinion that Mr Ducat’s heavy work duties during his Army Service “contributed in a material way to the development of the bilateral knee osteoarthritis’.

25. In support of his opinion, he relied on Mr Ducat’s statement and on Dr Williams’s medical certificate in which it was claimed that Mr Ducat’s bilateral knee osteoarthritis “was already chronic” in 1987. He also relied on an assumption that “the likely onset of the osteoarthritic process would have been in the mid to late 80’s” but provided no other reasons.

26. In his oral evidence, Dr Cossetto confirmed that his opinion on causation was firmly based on the medical certificate from Dr Williams and Mr Ducat’s first statement.

27. In the course of cross-examination it was clear that in forming his opinion Dr Cossetto had paid little attention to the epidemiology and recognised risk factors in respect of the constitutional and degenerative nature of osteoarthritis.

28. I note that in Dr Williams’ referral letter, as well as in Dr Cossetto’s consultation record and letter of 10 December 2008, there was mention of “chronic bilateral knee osteoarthritis” since 1987.

29. In his letter, Dr Cossetto also noted that the x-rays performed on 11 June 2008 showed “very mild osteoarthritic change in each knee joint”. This would appear to be somewhat inconsistent with a proposition that Mr Ducat had been suffering from “chronic bilateral knee osteoarthritis” for over 20 years.

30. It is submitted, on behalf of Mr Ducat, that the Tribunal should prefer the opinions of Dr Williams and Dr Cossetto over Dr Gray because of their years of experience in treating Mr Ducat and because Dr Gray “only saw Mr Ducat on one occasion, and has not been his treating doctor at all”.

31. This submission, in my view, suggests a failure to appreciate the role of an independent medical expert.

32. The purpose of the use of expert evidence in proceedings is for a Tribunal or Court “to receive the benefit of the objective and impartial assessment of an issue from a witness with specialised knowledge (based on training, study or experience).[7]

    [7] The Federal Court Expert Evidence Practice Note (GPN-EXPT) dated 25 October 2016.

33. The value of expert opinion evidence is determined by the “assumptions adopted by the expert (i.e. the fact or grounds relied upon)” and his or her reasoning “expressly stated in any written report or oral evidence given”.[8]

    [8] Ibid.

34. In his written report, Dr Gray recorded a detailed and accurate medical and employment history and provided a comprehensive assessment of the available documentary evidence. He concluded that Mr Ducat suffered “constitutional bilateral knee osteoarthritic/ degenerative change” and that his Army service did not cause or contribute to the knee condition.

35. In his oral evidence, Dr Gray confirmed his opinion that Mr Ducat’s Army service did not cause or contribute to his “bilateral knee osteoarthritis” and provided additional reasons.

36. In my view, in both written and oral evidence, Dr Gray provided a persuasive independent assessment of Mr Ducat’s knee condition. He had regard to the totality of Mr Ducat’s employment history, his weight history, his risk factors, his medical records, and his reasons and opinions demonstrated an understanding of relevant medical literature in respect knee osteoarthritis.

    Conclusion

37. On consideration of the evidence before the Tribunal, I am satisfied, on the balance of probabilities, that Mr Ducat’s bilateral knee osteoarthritis was not contributed to, in a material degree, by his Army service.

38. The evidence, in my view, actually points to a conclusion that there was no contribution to Mr Ducat’s bilateral knee osteoarthritis by his Army service.

39. In reaching my conclusion, I have preferred the evidence of Dr Gray.

40. The evidence of Dr Williams and Dr Cossetto I found to be incomplete and unconvincing.

41. Their evidence suggested a poor understanding of the nature of degenerative osteoarthritis of the knee combined with an attempt to satisfy the requirements of the legislation without proper evaluation of Mr Ducat’s actual knee condition.

42. It follows that Mr Ducat’s ‘bilateral knee osteoarthritis’ is not a ‘disease’ for the purposes of s5B of the DRC Act and therefore, he is not entitled to compensation under s14 of the DRC Act.

    DECISION

43. For the reasons set out above, the Tribunal finds that Mr Ducat’s ‘bilateral knee osteoarthritis’ is not a ‘disease’ for the purposes of s5B of the DRC Act and, therefore, the Commonwealth is not liable to pay compensation under s14 Of the DRC Act.

44. The decision under review is affirmed.

I certify that the preceding 93 (ninety-three) paragraphs are a true copy of the reasons for the decision herein of Dr I Alexander, Senior Member

.....................................[sgd]...................................

Associate

Dated: 24 March 2021

Date(s) of hearing:	1 March 2021
Solicitors for the Applicant:	Tony Latimore, Legal AID NSW
Solicitors for the Respondent:	Anella Bortone, Sparke Helmore Lawyers