2. Notwithstanding that, as it were, prima facie ground of complaint available to the appellant, it seems to me that the course which Kelly J. took was completely justified, as his reasons disclose. The finding he made that there was an injury in compensable circumstances, having regard to the evidence of the doctors who saw the worker in late 1984 and early 1985, is a finding which is, it seems to me, virtually irresistible. And it does not throw any doubt on the finding that in his evidence before the magistrate the worker himself apparently made no particular reference to that incident.

3. So far as the other issue is concerned, the issue of incapacity, one answer to the complaint which the appellant makes is - as I think Wilcox J. has pointed out - that, although on reading the three or four pages of the learned magistrate's reasons I am left with a strong impression that he was quite unwilling to give any credence to the evidence of the worker, he does not, in terms, say so, and he does not give an account of any reasons which he might have had for that conclusion. In those circumstances, and upon an obviously very careful and exhaustive consideration of the whole of the evidence, Kelly J. was prepared to come to findings favourable to the worker without very much reliance upon the oath of the worker himself, but certainly, without any acceptance by him of the magistrate's apparent unfavourable view of the worker as a witness. In my opinion, Kelly J. was justified in the course he took. The justification, I think, can only be vindicated, so far as this court is concerned, by pointing to the persuasiveness and cohesion of the reasoning Kelly J. exhibits for his conclusion that incapacity did continue and was an incapacity, in a legal sense, caused by the injury.

4. The remaining point, as to what it is that constitutes the causal relationship between the compensable injury and the continuing incapacity, is one which was expressed by his Honour in terms of the reasoning of Toohey J., with whose judgment all of the other members of the High Court agreed in Asioty's Case [1989] HCA 40; (1989) 87 ALR 385. Asioty was a case concerned with disease, and it would appear that Kelly J. has dealt with this case as a case of injury, although he does from time to time make reference to disease. Asioty is really concerned with two quite different questions. In the first case, Toohey J. was concerned to identify precisely what it was that could be described as aggravation, and with that Kelly J. was not, for present purposes, concerned. The second question is the one that he was concerned with, and we are concerned with. The question may be put in this way: do you show incapacity for work by injury by showing that, as a result of physiological events consequent only upon the injury, the worker is in such a condition that if he returns to work he will produce symptoms of sufficient gravity to make it impossible for him to continue? This worker, like Asioty, was - at any rate, while he abstained from heavy physical work - not in any real sense unable to work, if you think of work in the abstract. But Kelly J. was able to conclude upon evidence, to some of which Wilcox J. has referred, that once he went back to the kind of work that he was qualified to do, the only kind of work he was likely to be able to get, he would suffer pain, and that the cause of that pain was the injury, in the sense that the injury had enhanced and increased his susceptibility to disabling pain in consequence of work of that kind. It seems to me that the reasoning in Asioty's Case is authority for the conclusion that that is sufficient to show entitlement to workers' compensation. It may mean no more than what is said when the doctor says, as Wilcox J. quoted from the evidence, "I told him not to go back to work." Not that he could not pick up the jackhammer and start using it. He was not incapacitated in that sense, but he was incapacitated in the sense that the opinion of the medical witness - and accepted by the court - is that once he did so, the incapacitating pain would occur and that he was brought to that point by the injury. And in that sense the injury did something which it is to be supposed, if one accepts this reasoning, the underlying condition upon which the injury operated would not have done.

5. For those reasons I would accept that the conclusion of Kelly J. and his reasons for his conclusion about incapacity are unassailable.

This is an appeal against a decision of Kelly J., whereby his Honour allowed an appeal against an award made by a magistrate, Mr. Michael Ward, in connection with a claim for compensation under the Workers' Compensation Act, 1951. Kelly J. remitted the matter to the magistrate for the entry of the appropriate award in the light of the findings made by him. Those findings, in effect, were that the appellant for compensation, Pertti Kattelus, the present respondent, had sustained a compensable injury in the course of his employment by Wakep Pty Limited, the present appellant, during December 1984; which injury resulted in his incapacity for work up to the date of the trial before the magistrate and continuing.

2. The principles which govern appeals to a single judge of the Supreme Court against decisions of magistrates in workers' compensation cases have been referred to previously in this Court and in the Supreme Court: see David Jones (Australia) Pty. Limited v. Arauner (unreported, Full Federal Court, 9 November 1982) and Selleys Chemical Company Pty Limited v. Grahame (unreported, Miles C.J., 8 October 1986). There is no need to repeat what was there said.

3. The proceeding before Kelly J. was a rehearing of the matter in which his Honour was obliged to form his own view about the facts and to draw any necessary inferences, but bearing in mind the view expressed by the magistrate about those facts and that he lacked the advantage of seeing and hearing the witnesses himself. How significant that advantage will be is a matter which depends upon the circumstances of the particular case. In the present case, no issue of credibility arose. The magistrate had the advantage of seeing some photographs and a video film in which the respondent was depicted carrying out particular activities. But Kelly J. also viewed this material.

4. The real problem in the case was the assessment of the medical evidence. In this regard, it seems to me that Kelly J. was in as good a position as the magistrate. Although his Honour did not hear and see the medical witnesses, he had their reports and a transcript of their oral evidence. As I have said, there was no question of the credibility of any of these witnesses.

5. There was no issue at the trial about the existence of a relationship of employee and employer between the respondent and the appellant. Nor was it denied that, as suggested by the respondent, he had been employed for some weeks prior to 18 December 1984 as a building labourer on a construction site; and, in particular, that he had been required to use a jack-hammer for substantial periods of time.

6. The applicant consulted a general medical practitioner, Dr G.B. Philip, on 18 December, complaining of back pain. He was apparently advised not to return to work with the appellant and he did not do so. Apart from a short "trial" period of work some time later, the respondent has not worked since.

7. In his reasons for decision the learned magistrate said that he was not satisfied that the respondent ever sustained "any significant compensable injury to his back". I do not understand what the magistrate intended to convey by the word "significant". An injury is either compensable or not, no question of degree arises. But whatever was meant, Kelly J. did not agree. At p 25 of his reasons for judgment his Honour said:

"I do not think it was fairly open to the

learned Magistrate to conclude that the

appellant had suffered no compensable

injury. Two doctors gave evidence of

having seen muscle spasm shortly after the

appellant ceased work in December 1984 and

the learned Magistrate did not indicate

that he disbelieved either of the doctors.

This court is in as good a position as was

the Magistrate to draw inferences from

that evidence."

8. I agree with this assessment of the position. It is sufficient to refer to the evidence of Dr W.J. Coyle, an orthopaedic surgeon, who first examined the respondent on 21 January 1985 and, subsequently, on a number of occasions.

9. In relation to his first assessment, Dr Coyle gave this evidence:

"Doctor, when you first saw him, you said

he did present with abnormal signs in

relation to his back?---Yes.

And what were they?---The back was stiff,

he had a spastic - he had a lateral

curvature of the spine which was due to

muscle spasm. That is an objective finding.

That is objective, yes?---Yes, that cannot

be, I do not believe that can be

simulated. And he had some restriction

with straight leg raising. He did not

have any signs of neurological deficit in

his lower limbs, but he did have evidence

that his back was painful and was causing

him trouble then."

10. This evidence was neither contradicted nor challenged at the trial. Nor, although Dr Coyle referred to the objective nature of the symptoms observed by him, did the magistrate find that the respondent had simulated, or attempted to simulate, his symptoms or otherwise tried to mislead either the doctors or the court.

11. Dr Coyle formed the view, on 21 January 1985, that Mr Kattelus was unfit for work. He has never since considered him fit for his previous employment but only for light work, if available.

12. Once initial incapacity be found, the next question is the duration of that incapacity. It is common ground amongst all the doctors who dealt with the matter - five of them in all - that, on medical grounds, the respondent ought not to return to work as a builders labourer. But counsel for the appellant submitted that this evidence does not mean that the respondent remains incapacitated, within the meaning of that concept in workers' compensation law. The reason why he ought not to return to construction work, said counsel, is that he is a middle-aged man (aged 45 at the time of the trial) with a degenerative spinal condition which would occasion him risk of injury even if the December 1984 injury had never occurred.

13. No doubt these statements are true. But the matter is not as simple as that. Two of the medical witnesses were asked to comment about the ongoing significance of the December 1984 injury. In response to a question from the magistrate, Dr Gytis Danta, a neurologist, said:

"Well, it is very common for patients,

particularly with a history of recurrent

chronic backache, to get acute exacerbations,

presumably due to disc lesions, whilst bending

and lifting, and such patients, once they have

had an episode, are much more likely to get

similar changes and often subsequent injuries

are more severe than the first ones."

14. Later, he expanded this opinion in response to questions from counsel:

"Doctor, you said that he had an acute disc

lesion from which he has recovered but you have

recommended against him doing heavy work to

prevent further damage. And then you went on

to say that he is more likely to get subsequent

damage if he engages, as I understand your

evidence, from heavy work, once he has had an

acute disc lesion?---Well, this is common experience.

Why is that so?---Well, I suppose it is

difficult to answer, but as I mentioned before,

once a disc becomes disrupted it is never

normal and then lesser trauma can often produce

another acute episode.

And you went on to say, in cross-examination,

that the next episode is - I might be wrong, I

did not know whether you said usual or often -

worse than the first?---Well, this again, is

general experience.

Why is that the case?---Again, I cannot answer

that but when we see patients - we have had,

say, three or four acute episodes of backache

sciatica - it is very common to see the

subsequent ones to be more prolonged, more

severe, not responding so well to treatment,

compared with the initial ones.

And you would not regard it then as proper

advice to advise him to go back into heavy

work?---Well, all I would advise him against is

heavy lifting and bending."

"Has the disc been weakened by the episode that

Dr Coyle has given?"

"Well, it has been weakened. This is what I

have said, that once a disc is disrupted it is

never normal and it is often, with much less

provocation, liable to cause further symptoms."

17. Dr Peter Morris, an orthopaedic surgeon, gave similar evidence:

"When he aggravated his disc prolapse in 84; or

if you accept that that is what happened - has

that aggravation continued in relation to his

back situation, or has that resolved itself

back to the pre-jack hammering incident?---It

has resolved itself in as far as I do not think

he has got a lot of discomfort at the present

time, but whereas before the pre-jack hammering

incident, he could, theoretically, jackhammer,

now I think he is at a stage where, if he tried

it, he would have back pain a lot sooner.

Can you answer this, then. Has the

jackhammering put him into a situation that he

can no longer do heavy work of the

jackhammering sort?---Yes, I think it has put

him into a different category, yes."

18. In dealing with the question of continuing incapacity, Kelly J. applied the decision of the High Court of Australia in Asioty v. Canberra Abattoir Pty. Limited [1989] HCA 40; (1989) 87 ALR 385, see especially per Toohey J. at 390. In my view he was correct to do so. Although the evidence clearly establishes that the respondent has a degenerative condition of his back which created some problems for him prior to his employment by the appellant, both Dr Danta and Dr Morris made it clear that the continuing effect of the compensable injury is to make the respondent more vulnerable to a future aggravation than he would have been if that injury had not occurred. Independently of anything else, the effect of that injury is to preclude his returning to heavy work, such as employment as a builders labourer.

19. Reference was made during the argument to evidence about the respondent's perception of pain and the existence of some psychogenic overlay which would, in any event, preclude his returning to heavy work. In the view I take, it is not necessary to consider this alternative basis for the claim of continuing incapacity.

20. For the above reasons, which substantially coincide with those of Kelly J., I would dismiss the appeal and order that the appellant pay to the respondent his costs of the appeal.

I agree that the appeal be dismissed and the respondent's costs of the appeal be paid by the appellant.