Davis v Comcare

REASONS FOR JUDGMENT 1 This is an appeal from a decision of the Administrative Appeals Tribunal given on 6 February 2003, in which the AAT affirmed a decision of an Independent Review Officer (IRO) given on 21 February 2001 in which the IRO determined that the respondent was not liable to pay compensation to the appellant pursuant to the Safety, Rehabilitation and Compensation Act 1988 (the Act). 2 The questions of law which are said to be raised by the appeal are: '1. Whether the Administrative Appeals Tribunal in its decision of the 6th day of February 2003 gave any or any adequate reasons. 2. Whether the decision of the Administrative Appeals Tribunal of the 6th day of February 2003 was in accordance with the evidence. 3. Whether in accordance with the evidence the Administrative Appeals Tribunal should have found that the respondent was liable to pay compensation to the applicant for musculo ligamentus [sic] strain of the lower back.' 3 A number of grounds were advanced to support the questions of law which were said to be raised on the appeal. The appellant, by his counsel Mr Britton, addressed each of those grounds separately. 4 The grounds identified in the notice of appeal are: '(1) The learned Senior Member erred in failing to consider adequately or at all evidence of the applicant's history of work duties from the 2nd of January 1990 until the applicant's retrenchment in September 1997. (2) The learned Senior Member erred in failing to consider adequately or at all, the opinions of Dr R Bhola, Dr V K P Yeung, Dr P Sing, Dr N Broadhurst and Dr F Lim that the applicant's history of work duties from the 2nd of January 1990 to the applicant's retrenchment in September 1997 would on balance of probability have aggravated or exacerbated a musculo ligamentus [sic] condition of the applicant's spine. (3) The learned Senior Member erred in failing to consider the opinion of Dr Mills that the applicant's history of work duties from the 9th of January 1990 to the applicant's retrenchment in September 1997, could have affected the applicant's spinal condition and, that a degenerative condition of the spine could have been aggravated by the applicant's work. (4) The learned Senior Member erred in finding, against the evidence or the weight of the evidence that the condition of the applicant's spine was unrelated to the applicant's history of work duties from January 1990 until the applicant's retrenchment in September 1997. (5) The learned Senior Member erred in finding that the only major factor to support the applicant's argument that there was a compensable injury was Dr Broadhurst's opinion of internal disc disruption which finding failed to take into account the opinions of Dr Bhola, Dr Yeung, Dr Singh and the totality of the opinion of Dr Broadhurst. (6) The learned Senior Member erred in finding, against the evidence or the weight of the evidence, that the condition of the applicant's spine was as a result of a minor degenerative condition of the applicant's lower back.' 5 The appellant was born on 27 January 1951 and is presently 52 years of age. He is a former railway employee of the Commonwealth Railways which later became the Australian National Railways, and he was based in Port Augusta. 6 In January 1990 his duties included driving trucks and inspecting cars along various railway lines in South Australia and extending into the Northern Territory and Western Australia. 7 On 2 January 1990 he injured his lower back whilst lifting a metal plate. There is no dispute that he suffered an injury on that day although the evidence seems to suggest that the appellant has given different accounts of the incident giving rise to the injury. In the Injury/Illness/Hazard Report which he submitted to his employer on 29 February 1990 the appellant stated: 'Strained lower back whilst lifting equipment onto truck after completing bogie change at Bookaloo.' 8 A week later on 9 January 1990, whilst working in the motor shop at Port Augusta, he suffered an aggravation of that injury whilst lifting a heavy compressor. 9 He may have consulted his medical practitioner, Dr Bohla, on that date. A later certificate of Dr Bohla's suggests he first saw the appellant on 9 January 1990. The appellant submitted the Injury/Illness/Hazard Report on 29 February 1990. 10 The appellant consulted Dr Bohla in February/March 1990. On that occasion he complained of both incidents. Dr Bohla diagnosed 'musculo ligamentous strain lower back' but considered him fit to work 'having physio'. 11 The appellant did not undergo any medical treatment in relation to the injury or injuries of 2 January and/or 9 January 1990 until 18 October 1990 when he again consulted Dr R Bhola. 12 When Dr Bhola saw the appellant on 18 October 1990 he was told by the appellant that he had injured his back in January 1990 during a derailment when he pushed a piece of steel from under a truck. Dr Bhola again diagnosed the appellant as suffering from a musculo ligamentous strain in the lower back. X-rays taken by Dr Bhola showed degenerative changes in the lumbo sacral spine. 13 Between January 1990 and September 1992 the appellant occasionally consulted his general practitioner in relation to his pain and received ongoing chiropractic treatment. However he continued in his employment carrying out the same work as he had done before, except that he was advised, and I think accepted the advice, not to lift more than 25 kg. 14 On 23 September 1992 he was walking back to his place of work when he felt a sudden sharp pain in his lower back in the same place as he had suffered pain in January 1990. He was taken to the Port Augusta medical centre where he consulted Dr Singh (a partner of Dr Bohla) and was given a certificate of unfitness for work until 29 September 1992. On 30 September 1992 he was certified fit for normal duties. He returned to work on normal duties, except that he attempted to avoid heavy lifting. He submitted a further Injury/Illness/Hazard Report in relation to that incident in which he described the original 3 (sic) January 1990 incident: 'Lifting steel plate from under rail truck at Bookaloo.' 15 Dr Singh submitted a medical report to the respondent on 18 January 1993 in which he wrote: 'I saw Mr John Davis on 23/9/92 complaining of gradually increasing severity of pain in the back. He has come to a point where he needs a bit of help. He hurt his back on 9/1/90 and has been going to the chiropractor every now and then for the past 18 months to 2 years. He has been in a satisfactory condition but lately the pain has been increasing gradually. The last two days the pain has been increasingly worse and he has been unable to carry out his routine work. He is still attending the chiropractor services. On examination I did not find anything that was related to disc under compression, his SLRT was 90. I than [sic] advised him to increase his Voltaren 50mg BD and I gave him some time off from 23/9/92 to 29/9/92. When I reviewed him on the 29/9/92 he was better and agreed to go back to work, which he did. According to his past his medical complaints there seems to be a link between the present increasing pain due to his past medical problems, starting on about 2/1/90 [sic] and I gave him the medical certificate on that basis. I saw him for other medical problems on the 24/12/92 and although he still had pains in the neck and the back he his able to carrying on working to some extent.' 16 Between 1992 and 1997, the applicant sought medical attention from his general practitioners. 17 Dr Singh referred the appellant to a chiropractor who treated him monthly or six weekly 'to prevent worsening of Mr Davis' condition, will continue to tighten in affected areas due to initial damage'. 18 At the request of the respondent Dr Bohla addressed the need for that treatment in a report dated 28 November 1995: 'With reference to your letter addressed to Mr Davis on the 14th November 1995 concerning chiropractic treatment by Andrew Hunter, I would like to say that this patient injured his lower back in 1990 at work when he lifted a steel plate and has had recurrent low back pain since then. He has managed to remain at work but avoids heavy lifting and finds that he has stiffness in the lower back which is relieved by chiropractic treatment every 4 to 6 weeks. He has seen Dr Singh on a regular basis since 1991 but no bills have been sent to Comcare seeing that he generally has other problems and has been billed to Medicare. It is in my opinion that he continues to need and derive benefit from chiropractic treatment every 4 to 6 weeks and this enables him to stay at work without losing much time off work. I think it is reasonable for him to continue with this treatment and this can be reviewed after a further period of 12 months.' 19 On 15 April 1997 the appellant consulted Dr Bohla, who diagnosed him as suffering from a recurrence of low back pain caused by lifting at work. 20 On 23 April 1997 Dr Yeung, a general practitioner in partnership with Dr Bohla and Dr Singh, certified the appellant as fit to return to work 'not to lift > 15kg, not to bend repeatedly'. 21 The appellant was retrenched on 9 September 1997. 22 In a report dated 15 May 1997 four months before the appellant's retrenchment, Dr Yeung, a general practitioner in partnership with Dr Bohla, reported to the respondent that he had referred the appellant to Mr Felix Lim, orthopaedic surgeon. An x-ray of the appellant's lumbo sacral spine and sacral-iliac joints had been taken and it showed: 'There is only very minor degenerative lipping of the edges of some of the mid and lower lumbar bodies. The disc at L5S1 is a little narrow and there is slight posterior displacement of L5 on S1 by 2 or 3 mm. This mat [sic] be evidence of early disc degeneration but the bones remain normal and there is good alignment elsewhere. The bone density is satisfactory and the pedicles are intact. Both sacro-iliac joints appeared normal with no erosion or degeneration.' 23 The appellant underwent a left sacro-iliac joint injection under CT scanning control on 29 April 1997. 24 A report of that procedure showed: 'In the prone position and under local anaesthesia, a needle was placed into the sacro-iliac joint adjacent to the site of the patient's maximum discomfort. Contrast verified the intra-articular positioning of the needle tip and at this site 3 cc of 0.5 per cent plain Marcaine and 2 cc of Celestone chronodose were injected. There was some reproduction of the patient's symptoms upon injection of this fluid but these rapidly subsided.' 25 Dr Yeung offered the opinion that the appellant was suffering from left sacro-iliac joint pain which radiates up into the thoraco lumbar region and which gives rise to the low back pain that he was then experiencing. 26 He said that the appellant's pain was directly related to his employment and the incident on 2 January 1990. He offered the further opinion that the degeneration showed in the x-ray of the appellant's lumbar spine was most likely the result of the injury of 2 January 1990. Dr Yeung said that the appellant was suffering from a work related injury. 27 Dr Yeung offered the opinion that the painful effects were likely to be permanent as 'there are regular recurrences of his symptoms and the degenerative changes in his spine will only deteriorate with time'. He said '[p]rognosis is guarded and recurrence of low back pain and left sacral pain is expected from time to time.' 28 He recommended that the appellant should not be required to lift loads heavier than 15 kg and should not be required to bend repetitively: 'He should be allowed to continue with his "modified duties" so that he can work at his own pace.' 29 Dr Yeung provided certificates after that date that the appellant should only work on modified duties. 30 The appellant resumed work and remained at work carrying out his physical activities which were reasonably heavy until his retrenchment on 9 September 1997. He was advised in writing that the position he occupied would be 'surplus'. 31 The appellant's evidence was that prior to his retrenchment he attended a meeting with representatives of his employer and his union. At that meeting he was shown Dr Yeung's report, to which I have just referred, and told that as a consequence of the information contained in that report he was to be retrenched. The AAT did not make any findings on this aspect of the appellant's evidence but there was no evidence to contradict the appellant's account. The appellant's evidence was generally accepted by the AAT, although no precise finding to that effect was made. 32 On 30 November 1997 Dr Lim, orthopaedic surgeon, provided the respondent with a medical report concerning the appellant. He first saw the appellant about his back condition on 26 March 1997. It was he who ordered the x-rays to which Dr Yeung had referred in his report of 15 May 1997. He wrote: 'Mr Davis told me that he injured his back in the course of his work in 1992. He had not mentioned about any back injury at work in 1990 and I have not taken any history regarding this. From clinical and x-ray examination in April 1997, it appears that he suffered ligament injury of the lumbar spine, probably in the left sacroiliac region. There was no clinical or x-ray evidence of any serious injury. This is consistent with the history of injury as related to me. It is difficult to ascertain this from clinical examination carried out several years later. He has x-ray evidence of degenerative changes of the lumbar spine which is consistent with his age. This is not necessarily symptomatic on its own but may have been aggravated by his work. I could not determine from the clinical and x-ray assessment some five years after the event whether his current back pain is the direct result of the effect of his employment. As far as I could determine, there was no pre-existing back pain or other contributing factor to his back injury. I did not recommend any treatment other than to continue with medication and physiotherapy. His symptoms have not resolved at the time of the examination several years after the event. Therefore, it appears unlikely that his back pain will resolve in the foreseeable future. Based on the examination in April 1997, I am of the opinion that he has approximately 7% loss of function of the lumbar spine as a result of the on-going symptoms.' 33 Nothing turns on the first paragraph there referred. The appellant inadvertently gave the wrong date. 34 His general practitioners certified from time to time that he was unfit to work. Certificates were given for periods up to and including 31 December 2000. 35 On 14 September 2000 Comcare obtained a medical report from Mr Duthie-Mills, orthopaedic surgeon, and on 11 October sent a copy of that report to the appellant. Comcare advised that it intended to review his claim to decide whether his entitlements to benefits under the Act should continue. 36 The appellant told Mr Duthie-Mills: '... he attended a trail [sic] derailment at Bookaloo. It was a very hot day, approximately 50o and Mr Davis described pushing a heavy steel plate from under a rail truck. Later, he picked up the plate and put it on the back of a truck with difficulty and following this, he noted pain in his lumbosacral region to the left of the midline.' 37 That account seems to incorporate both versions previously described. 38 Mr Mills offered the following opinion: 'On the information at my disposal it would appear likely that Mr Davis has suffered a soft tissue injury of his lower back as a result of a lifting incident in his work in 1990. Recent x-rays demonstrate relatively minor but definite disc degenerative disease in his lumbosacral spine. It is notable that Mr Davis has complained of progressive deterioration in his symptoms despite chiropractic treatment and also, during the three years since he stopped working with Australian National Rail. It would appear likely that Mr Davis continuing and progressive deterioration in symptoms is due to some progress in the underlying disc degenerative disease in his lumbosacral spine. In reply to the specific questions contained in your letter dated 31 August 2000: 1. What is the history that Mr Davis gave at the consultation. The history as given to me by Mr Davis is contained in the body of my report above. 2. What is the specific diagnosis of the medical condition from which Mr Davis currently suffers (if any)? Mr Davis presents with definite but mild disc degenerative disease in his lumbosacral spine. He also presents with ischaemic heart disease, with angina and some form of cardiac arrhythmia which has demanded the insertion of a pace maker. It is beyond my area of expertise to comment further in respect of Mr Davis' cardiac disorder. 3. Please detail the results of the tests (if any) that you have organized and comment on the findings in relation to Mr Davis' injury. I have commented above on the x-rays that were presented for review. As I have noted previously, Mr Davis does demonstrate mild but definite disc degenerative disease in the lumbosacral region. 4. On the balance of probability, is Mr Davis' current condition related to: a. the incident at work on 2 January 1990? If so, how? b. some other aspect of his employment with Australian National Rail? If so, what? c. factors unrelated to work? If so, please detail what they are. d. The natural progression of an underlying condition? In my opinion Mr Davis current condition is related to (d) the natural progression of an underlying condition i.e. the mild disc degenerative disease in his lumbosacral spine. 5. If the condition is still related to the employment, to what incident in his employment and has the employment: i. caused the condition? ii. aggravated or accelerated a pre-existing condition? If so, please provide details of the pre-existing condition and advise whether the effects of the aggravation are continuing or have ceased? In my opinion Mr Davis' employment has not caused the condition of disc degenerative disease of his lumbosacral spine. This is an age related condition, but in my view it is not possible to entirely exclude that the condition has been aggravated or accelerated by the reported incident in 1990. However, no radiologic or other special investigations are available from 1990 to confirm that the disc degenerative changes presently noted in his low back were present at that time. 6. In a report from Dr Felix Lim dated 30 January 1997 he states "He has X-ray evidence of degenerative changes at the lumbar spine which is consistent with his age" however, Dr Victor Yeung in his report dated 15 May 1997 states "the degeneration in his lumbar spine as shown in the X-ray of 1 April 1997 are most likely the result of his injury of 1 February 1990". In your opinion what is the cause of Mr Davis' degenerative back condition? In my opinion the most likely cause of Mr Davis' degenerative back condition is an age change as expressed by Dr Felix Lim in his report of 30 November 1997. 7. On the balance of probability as distinct from mere possibility, would Mr Davis be in the same condition today regardless of his employment contribution on 2 January 1990? On the balance of probability Mr Davis would in my opinion, be in the same condition today regardless of his employment contribution on 2 January 1990. 8. Given that Mr Davis has not worked since 12 September 1997, has the employment component of his condition now ceased and has the aging process now overtaken any contribution from his employment with Australian National Rail? In my opinion the employment component of Mr Davis' condition has now ceased. 9. In your opinion is Mr Davis totally incapacitated for any employment? If not, what type of duties can he undertake and what restrictions (if any) would be applicable? In my opinion Mr Davis is not totally incapacitated for any employment. He would be fit to carry out a wide array of selected light work, which does not involve any heavy manual labour, repetitive bending or heavy lifting. He would for example, be fit enough to undertake duties as a gate keeper or working on a console in a service station. 10. Is the current treatment of a monthly chiropractic session appropriate and what therapeutic benefit would it be providing? What treatment would you recommend? It is likely, from the history provided by Mr Davis, that his monthly chiropractic sessions have resulted in transient symptomatic benefit only. It is unlikely that the chiropractic treatment will alter the ultimate outcome here. In my opinion Mr Davis would be well advised to continue with a self-directed gentle exercise program and to take suitable analgesics as necessary. 11. What is the prognosis? It is difficult to ascertain the prognosis, but I consider that Mr Davis would be fit enough to continue in paid employment for at least a further decade in respect of his musculoskeletal condition. It is beyond my area of expertise to comment on Mr Davis' work capacity taking into account ischaemic heart disease.' 39 The contents of the report were unfavourable as far as the appellant was concerned. 40 The respondent invited the appellant to 'present further evidence in support of his claim'. 41 The respondent also obtained a further report from Dr Lim dated 19 November. He had not seen the appellant since April 1997. In his report he said: 'The following are answers to your specific list of queries: 1. I believe he is suffering from muscular and ligamentous strain of the lumbar spine. There was no clinical evidence that he suffered any lumbar disc prolapse or nerve root impingement. As far as I know, he did not have CT scan or MRI of the lumbar spine. 2. I first saw him about his back pain in 1997. He told me that he injured his back at work in 1992 while moving a steel plate. From your letter, it appears that this happened on 2 January 1990 and not in 1992. It is difficult to explain how a lifting episode that appeared to have caused muscular and ligamentous strain of the lumbar spine should still be causing back pain more than 10 years later. The type of low back pain that he complains of is very common in the general population. It is quite common for these to be naturally occurring; and it is not always possible to determine the exact cause. There is often no definite history of injury. Be that as it may, I don't think it is possible in 1997 to determine whether his back pain was caused by an injury in 1990. Do you have any medical report documenting about his back injury in 1990? Is there any documentation of the clinical findings about his back pain soon after his injury in 1990? It may be possible to compare such findings to the current clinical findings to see if they are similar. 3. He had x-ray examination of the lumbar spine in 1997. This showed very minor degenerative changes. X-ray taken in November 2000 also showed only minor degenerative changes. I believe these changes are normal for his age. There is no direct co-relation between such observed x-ray changes and the presence of low back pain in the general population. 4. I am not aware of any other condition or factor contributing to the worker's current symptoms and incapacity at the lumbar spine.' 42 On 27 November 2000 Comcare decided that compensation payments should cease. On 27 November 2000 Comcare wrote to the appellant in the following terms: 'Dear Mr Davis Safety, Rehabilitation and Compensation Act 1988 I refer to your claim for musculo-ligamentous strain lower back and our letter of Wednesday, 11 October 2000. In that letter we advised you of the need to provide further evidence to support your claim. Comcare wrote to Dr Felix Limmo [sic] who re-assessed you on 01/11/2000 and requested a report on your condition. Dr Lim advised that he has only seen you three times, the time prior to the examination of 01/11/2000 being April 1997. At the recent assessment, clinical examination did not reveal any significant restriction of range of motion and he confirmed that the recent x-rays showed slight degenerative changes of the lumbar spine and he had referred you to another doctor for assessment. He reported "I believe these changes are normal for his age. There is no direct co-relation between such observed x-ray changes and the presence of low back pain in the general population". Dr Lim reports "It is difficult to explain how a lifting episode that appeared to have caused muscular and ligamentous strain of the lumbar spine should still be causing back pain more than 10 years later. The type of low back pain that he complains of is very common in the general populations. It is quite common for these to be naturally occurring; and it is not always possible to determine the exact cause. There is often no definite history of injury". Based on the medical opinion of both doctors' Lim and Mills, I am satisfied that on the balance of probabilities you are no longer suffering from a compensable condition. Therefore, having regard to the evidence presented and the provisions of the Safety, Rehabilitation and Compensation Act 1988, I have determined that on and from Friday, 8 December 2000, we are no longer liable to pay compensation for your claim under any provision of the Act. Your rights relating to my decision are explained on the enclosed sheet. If you have any questions in relation to this claim, please call Samantha Gilmore on 1300 366 979 or write to this office quoting the claim number stated above.' 43 On 8 December Dr Norman Broadhurst, musculoskeletal physician, at the request of the respondent provided a medical report. Dr Broadhurst had seen the appellant at the request of Dr Lim. He wrote: 'It would seem reasonable that this patient has sustained a significant injury which for unknown reasons has not resolved. His marked tenderness over the region of the iliolumbar ligament would make me think that that is the source of his pain with possible involvement of the upper aspects of the sacroiliac ligament. I arranged to have the area injected by Benson Radiology and when the needle was put into the lumbosacral area to inject the iliolumbar ligament, there was significant reproduction of his pain. The next day, the patient informed me that he had had a couple of hours relief which would reflect the analgesic affect of the local anaesthetic, but once this wore off, his pain went back to normal. Prognosis I feel that this man's difficulty is genuine and that attempts at mobilising, plus or minus injections should be the way forward at this time. Reproduction of his pain under image intensifier would support the genuineness of this man's claim. Ongoing treatment would consist of further injections and mobilising the tight lumbosacral area and if this was not successful, some thought might be given to sclerosing the area. With regard to Dr Duthie Mills' comments, while there are some degenerative changes, it is not possible to blame all pain on degenerative change. Dr Mills can not substantiate this as the cause of his pain which would require a provocative discogram to be done. Documentation of Mr Lewis's [sic] claim seems to be consistent since I've not seen him until nearly 11 years from the time of the accident, I cannot comment on this, only to say that it is likely that his pain has an ongoing relationship to the initial injury and the type of work that he has been doing. I would agree that chiropractic treatment is not going to alter the ultimate outcome and needs to be found a particular job which does not require heavy labour which is probably the cause of his current state.' 44 His opinion is at odds with Mr Duthie-Mills' opinions. 45 On 3 January 2000 Dr Bohla reported to the respondent. He had been supplied with Mr Duthie-Mills' report and Dr Lim's most recent report. After reciting the appellant's history, earlier investigations and diagnoses, Dr Bohla continued: 'Causation 1. I feel that the cause for this patient's symptoms is the injury in 1990 which caused a strain on certain ligaments, and of late this may have been aggravated by degenerative changes. 2. I believe that the incident of 1990 contributed to the onset of his condition. 3. I think that the onset of his condition was pushing the steel plate under the truck. His symptoms have been aggravated by the alternative duties of maintaining bogies. Treatment 1. He initially had physio, chiropractic treatment and pain killers. He later received injections in to the painful areas with only temporary relief. 2. He needs to continue self-motivated physiotherapy to keep active and pain killers as required. 3. As his problem will be a long term one I think he needs some guidance as to what sort activity he should continue on his own and not formal physiotherapy. 4. It is not possible for me to estimate costs of further treatment but I think that his treatment in future will be basically symptomatic. Incapacity 1. Mr Davis is unfit for his normal duties as a truck driver and a bogie maintainer at present. 2. It is possible that Mr Davis may be able to some work providing he avoids heavy lifting above fifteen kilograms and excessive bending or prolonged sitting.' 46 These two reports were received after the respondent's decision to cease payments of compensation under the Act. 47 Comcare was asked to reconsider its decision but on 21 February 2001 it decided to affirm its determination of 27 November 2000. 48 The IRO, in reconsidering her decision, did not refer in her reasons to the reports of Dr Broadhurst or Dr Bohla. She merely reiterated her previous opinion relying upon the same material as she had in November 2000. 49 The appellant applied to the AAT for a review of that decision. 50 The only other medical report of consequence received by either party prior to the hearing of the AAT was a further report from Dr Norman Broadhurst, dated 6 September 2001. In that report Dr Broadhurst reiterates his previously expressed opinion. In particular he said: 'As Mr Davis' impairment and his pain has been consistent for more than a decade, it is not feasible to say that his pain is solely due to degenerative changes, especially in light of his repeated complaints of his pain to the local medical profession. Lumbosacral pain can be due to a multitude of causes. The consistent complaint of this patient together with the biomechanics of the initial injury and his ongoing manual labour would support employment as being a significant contribution to his ongoing discomfort.' 51 The appellant gave evidence before the AAT. His evidence in chief was largely contained in a statement dated 10 January 2002 which was tendered to the AAT. His evidence was consistent with his complaints to medical practitioners over the previous ten or so years. In cross examination he identified as well as he could the number of times that he had seen his medical practitioners. 52 The appellant called Dr Broadhurst who repeated, in oral evidence, that ongoing manual labour would support employment as being a significant contribution to his ongoing discomfort. 53 In cross examination he suggested that the appellant might be suffering from an internal disc disruption. There had been no mention in his previous reports of the possibility of the appellant suffering from such a condition. When pressed on the recency of that opinion he said: 'That is a plausible reason for the initial injury and the non-resolution of that initial injury and it is not very often that I have to tell patients that: sorry, I can't help you one way or another, that is one of the conditions in which that is so. It is then over to the spinal surgeon if he wants to - to do anything about it.' 54 He was asked: 'Why didn't you mention that issue at the time you wrote your report in December 2000?' 55 He answered: 'I suppose, because at the time of dictating it when I have to dictate multiple reports I just - it didn't cross my mind to include it. I will confess my humanity and absent mindedness at the time. I am quite adamant that it is a reasonable thing to include in a report.' 56 In due course the Tribunal, in its reasons, preferred the evidence of Dr Lim and Mr Duthie-Mills. The AAT did not indicate why it preferred the reasons of those other medical practitioners. It may have been that the AAT was not convinced that Dr Broadhurst's opinions were well researched or well founded especially in light of the previously unexpressed opinion that the appellant was suffering from an internal disc rupture. 57 The respondent called Dr Lim who adhered to the view that it was not possible to determine whether the appellant's back pain was caused by an injury in 1990 or otherwise. He also expressed the view that 30 to 40 per cent of people of the appellant's age would show some signs of degenerative changes on x-ray in their lumbar spine. In any event, so Dr Lim said, the appellant had a residual working capacity. 58 In cross examination he accepted that it was possible that the work that Mr Davis had carried out after September 1992 and until his retrenchment might cause some sort of aggravation or exacerbation of his back condition. In particular, Dr Lim said that he would not disagree with Dr Broadhurst's statement which was: 'The consistent complaint of this patient, together with the biomechanics of the initial injury and his ongoing manual labour, would support employment as being a significant contribution to his ongoing discomfort.' 59 Mr Duthie-Mills gave evidence by video. At the time of the hearing before the AAT Mr Duthie-Mills was an honorary consultant orthopaedic surgeon in Auckland, New Zealand. 60 He was asked by the respondent's counsel during his evidence in chief to consider Dr Broadhurst's opinions expressed in the two reports to which I have referred. 61 In particular he was referred to a number of the opinions which Dr Broadhurst had expressed. He said: 'It is my contention that Mr Davis' continuing symptoms are due to a degenerative change in the low back.' 62 He was directed to Dr Broadhurst's opinion that the appellant might be suffering from an internal disruption and said: 'This is a concept of which I am not familiar and I am not certain as to how you might diagnose that in the absence of discography.' 63 When pressed he said: 'It's a concept with which I am unfamiliar but I suspect that to demonstrate this proposed internal disruption that one would have to carry out discography, or even an MRI scan of the spine, and the latter examination of course is contrary indicated in Mr Davis' case in view of the fact that he has a pacemaker. But from my point of view as an orthopaedic surgeon, it is not a concept that I would recognise.' 64 It was put to Mr Duthie-Mills in cross examination that the appellant's employment had aggravated whatever underlying condition the appellant suffered. Mr Duthie-Mills adhered to his opinion that his employment conditions had not caused a degeneration in the low back but at the same time agreed that a degenerative condition of the low back could be aggravated by injury. However, in the end he said he was of the opinion that the appellant's continuing symptoms were not in fact due to an aggravation of his pre-existing degenerative condition but due to the degenerative condition itself. He had particular regard to the fact that by 1997 the appellant had stopped working. (transcript 161) 65 It was Mr Duthie-Mills' opinion that the fact that the appellant's condition had not improved after the appellant ceased working suggested that the work was not a contributing factor to the condition. 66 He was cross examined in relation to Dr Broadhurst's opinion of an internal disc disruption. He was asked: 'Is this your position in relation to the suggestion that there may be internal disc disruption, that you say you can't say whether that is the case because a discogram, or an MRI has not been taken?' 67 Answer: 'No. My point - my position in respect of an internal disc disruption is that this is not a concept that I recognise but perhaps you could help me and tell me what you mean by that.' 68 Question: 'Yes, well, as I understand that Dr Broadhurst says is that the disc can be internally disrupted - quite a separate thing from say, say a prolapse disc.' 69 Answer: 'This is an unusual concept, as I say, which I don't understand.' 70 In its reasons the AAT set out the evidence of each of the witnesses in some detail but without any comment either favourable or adverse. 71 It then set out the appellant's and the respondent's submissions and drew conclusions in a chapter headed 'Discussion and Findings' which I set out: '72. The Tribunal in arriving at its decision has taken the evidence as a whole into account including all of the medical evidence and the submissions of counsel. It is not disputed that the applicant suffered an injury to his lower back on 2 January 1990. Nor is it disputed that the applicant suffered aggravation on two occasions, namely 9 January 1990 and on about 23 September 1992. The Tribunal is satisfied that such was the case and so finds. 73. During the course of his employment the applicant worked in Port Augusta with the railways. When he first joined the railways it was known as the Commonwealth Railways. During his time there was restructuring and the name changed to Australian National Railways (ANR). With the changes there was the fear of employees losing their jobs. The applicant believing that if he stayed away or took too much time off as a result of his back condition that he may lose his job. He explained that, despite his back condition he attended at work in order to protect his job. On the evidence before it this explanation is acceptable by the Tribunal. 74. However, some five years after the 1992 incident, namely 12 September 1997 the applicant was retrenched. At that time the applicant went about his work but was cautious in the weight he lifted and not to bend repetitively. The applicant stated that when first brought to his attention of the pending retrenchment he became aware of Dr Yeung's report (T18) which referred to his back condition. Notwithstanding his retrenchment, the applicant continued to receive weekly compensation payments until cessation on 8 December 2000. The explanation given for the cessation of the compensation payments was that the respondent was satisfied that the applicant no longer suffered a work-related condition. 75. From the date of the cessation the applicant had not found nor been engaged in any other employment. The applicant submitted that throughout that period he has been unable to find any suitable employment and has tried to do so through employment agencies in Port Augusta. On the other hand the respondent contended that the efforts by the applicant to find employment were purely tokenistic. As to this issue the Tribunal without again setting out the facts nor conversing the law is satisfied that given the applicant's condition, his age, education, work opportunities and regional location that he had made every endeavour to find employment. The Tribunal rejects the submission of the respondent as to this issue. 76. As previously stated the Tribunal in arriving at its decision takes into account all of the medical evidence. Dr Broadhurst reported on two occasions that it would seem reasonable that the applicant sustained a significant injury, but for which unknown reasons has not resolved. Likewise Dr Lim raised the question of it being difficult to explain how a lifting episode that appeared to have caused muscular and ligamentous strain of the lumbar spine should still be causing back pain more than ten years later. 77. There is no doubt and the Tribunal accepts that the nature of the applicant's injury was ligamentous, but that all the medical evidence revealed the presence of a degenerative change. Both Dr Lim and Dr Mills were satisfied that on the balance of probabilities the applicant was not suffering from a compensable condition. The only major factor before the Tribunal to support the applicant was introduced for the first time by Dr Broadhurst during his oral evidence, namely the notion of "internal disc disruption". This was dismissed by Dr Mills, who cast doubts on such notion. 78. There is no doubt and the Tribunal is satisfied and finds that the applicant suffered the initial injury and subsequent aggravation. To this end all the medical evidence is in agreement. The difference of opinion arises after the applicant's retrenchment and some ten years after the initial injury. Whilst the Tribunal is satisfied that Dr Broadhurst's evidence has much merit it is not satisfied that on the balance of probabilities that the applicant's condition since 8 December 2000 is related to the initial injury. 79. The Tribunal in arriving at its decision prefers and accepts the medical evidence of Dr Lim and Dr Mills. In so doing the Tribunal is satisfied that the applicant had mild, but definite disc degenerative disease and that as a result of his injury in 1990 and aggravation in 1992 had some musculo-skeletal problems but that the soft tissue injury had abated. The Tribunal is satisfied and finds on the medical evidence that the applicant had recovered from the compensable injury by 8 December 2000. The Tribunal further finds that the age related degenerative disease was the cause and not the compensable injury. The Tribunal is further satisfied that the applicant has not been incapacitated for work since 8 December 2000 as a result of the compensable injury but rather from naturally occurring degenerative changes in the applicant's lower back.' 72 The critical finding is contained in par 78 where the Tribunal states: 'Whilst the Tribunal is satisfied that Dr Broadhurst's evidence has much merit it is not satisfied that on the balance of probabilities that the applicant's condition since 8 December 2000 is related to the initial injury.'