"Q. And as time goes by and the joint continues to be used may some degeneration take place or further degeneration?
A. Well, the condition of chondromalacia progress is with the time [sic: ?progresses with time]. If it is exposed to same sort of injuries, that is if the kneecap keeps clicking out, the person has more injuries, that can lead to further deterioration."
62 When asked about change in gait from chondromalacia, Mr Khan said -
"A. Yes. When it depends on the degree of chondromalacia and what state it is in, acute pain, you can have chondromalacia and it might have settled down and may not give you any problem. He is asymptomatic if leading a quiet existence. If he is active then the condition can flare up. He can walk with bent knee gait, slight flexed knee, and slight limb [sic: limp] on the side, because full extension causes the upper part of that upper kneecap to touch the chondro and commonly it is the upper half of the medial side that's affected."
63 In cross-examination Mr Khan was referred to medical literature, and agreed that chondromalacia could result from overuse during athletic activity, from disuse following prolonged immobilisation, and from direct injury such as a blow to the patella from a car dashboard or an old patella fracture. He agreed that its treatment was difficult "because of the multiple causes and the general irreversibility of this degenerative process".
64 Mr Khan was then taken to the respondent's pre-army history. He agreed that the 1980 injury was the respondent's most traumatic injury. He agreed that slight crepitus and lateral movement of the left patella were "classic of chondromalacia": it will be recalled that these were found by Dr Cook in 1986.
65 The cross-examination continued -
"Q. Accepting the age of the young man involved at the time his knee was certainly not normal by the time he joined the Army, was it?
A. Well, he seemed to be asymptomatic by then. He was 18.
Q. Well it's just, Doctor, take your time over this, but that's just not the picture clinically of a normal knee, is it?
A. No, he had a few knocks, yes.
Q. But it's more than a few knocks. That sort of picture that's painted in the clinical records together with the notes taken by the examining doctor does not suggest a normal knee, does it?
A. No, not at the time, yes.
…
Q. Assuming, again, that the history that I have given you is correct, and having regard to what we discussed arising out of the literature, it's likely, is it not, if you make those assumptions, and have regard to the nature of chondromalacia and it's degenerative nature, that the chondromalacia was kicked off, if I can use an inelegant expression in 1980, and that what we have seen since then is the result of the developing, or degenerative process, working it's way, as it does, in people who suffer from it?
A. Can I explain my way, my answer to what you are saying?
Q. You must Doctor explain your way, because that's the way we get the best understanding?
A. From what I understand these injuries in 1980 and '81 he certainly, no doubt that he had a bad injury then and he had a few more injuries, I think, and as a result of this main injury we are talking about he was found by the doctors to have damaged the medial cruciate ligament. He had some laxity. He had swelling. All these things have been recorded and he had crepitus in the knee. What we are not aware of is whether he recovered from it or not. All I can tell you is that, yes, I agree with you that he could have been clicking the knee out since then, may be. I'm not sure.
Q. See, Doctor, you consider this please. See, on the basis of what you put to you at the beginning when I read to you from the literature ---
A. Yes.
Q. --- isn't the picture, assuming the accuracy of the history I put to you, isn't the picture of this man's history from 1980 classic of a diagnosis of the commencement of the degenerative process of chondromalacia in this young man in 1980?
A. He could have had chondromalacia in 1980 but the trauma of the injury in 1987 produced direct flap lesion- He had a little flap off the cartilage which looked like there was of a traumatic type."
66 Mr Khan was then taken to his report of 25 November 1993, and agreed that the flap off the cartilage was the tear to which he referred in that report and was a recent tear occurring in August 1993.
67 The cross-examination continued -
"WILLIAMS: Q. Doctor, I think I have just got two short matters. Do you agree with the proposition that this condition, chondromalacia, is often associated with patients with a family history of osteoarthritis?
A. May be, I am not sure about that.
Q. I have got to put two propositions to put to you. You have already agreed with the proposition that the condition is degenerative in nature, correct?
A. Not only degenerative.
Q. It can be?
A. It can be.
Q. It is often degenerative in nature?
A. No, not often. There is a lot of people come in with osteoarthritis.
Q. Perhaps I'll put the rest of this, and we will get to the point. If the process is degenerative in nature, that results in the knee being progressively more unable to withstand use and insult than a normal knee, it would usually manage without difficulty, doesn't it?
A. Yes.
Q. Thank you. If the condition is caused by trauma, doctor, and the patient continues to sustain knee injuries or knee complaints in circumstances where one wouldn't expect it, the capacity of the knee to withstand the normal insults of life diminishes, doesn't it?
A. Does it mean that the knee is not A grade compared to the normal knee, is that what it means [sic].
Q. Yes?
A. With chondromalacia the knee is not.
Q. It is not unusual for chondromalacia to be diagnosed in young people, is it?
A. It is not uncommon, yes.
Q. Often associated with athletic young people?
A. Yes.
Q. Some of the time the diagnosis comes about as a result of trauma, doesn't it?
A. Yes, sometimes.
Q. But not all?
A. No, many girls get, females more.
Q. Without necessarily presenting with a history of trauma?
A. Not necessarily, but athletics, so you know they are active.
Q. Doctor, some of the time in your experience, I suggest, are you able to identify a traumatic component to the diagnosis by probing the history of the patient?
A. Yes.
Q. And that even comes about for two reasons. First of all sometimes the traumatic incident might predate the onset of symptoms by a long period of time, months sometimes?
A. Yes, that is true.
Q. And sometimes the particular trauma that might be implicated by the on set of chondromalacia might be relatively mild?
A. Yes.
Q. It all depends?
A. Can I talk a minute. The chondromalacia can lie dormant and it may not cause any symptoms, and if you see that kneecap with the eyes, it may even look reasonably normal and the reason is that the person has probably learned to live with their limitations and knocks exposed to the traumas, but still if that person performs more active things it can become painful again.
Q. And it is typical of the nature of this disease, if we can call it that, that it does lie as you say essentially a-symptomatic for periods of time, then when something specific happens, whether trauma or stress, it will flair up?
A. Yes, but it can aggravate, make it worse.
Q. It can flair up?
A. You can have mild tendency for knee cap slipping out. It is not a disease, an expression telling you this, you can have injury.
Q. I am sorry about the word, use of disease, but at the end of the day each time from, by the very nature of the problem once there is an onset of it, each time there is an insult to the knee there is a potential for the condition to become progressively worse, potentially worse.
A. If it is there, depending on the spread of the disease.
Q. That is because the injured compartment that the potential femoral compartment when insults occur will shed debris and particles within the compartment?
A. Yes, when it is active it does that."
68 In re-examination Mr Khan said -
"SHORE: Q. At your arthroscopy you saw indication of chondromalacia in form of the oedema?
A. Yes.
Q. Recorded by grade 1 to 2?
A. Grade 1 to 2, yes.
Q. Doctor, of what significance would it be that in the arthroscopies conducted by Dr Shannon in 1987 and Dr Huntsdale in 1987 there was no reference at all to any occasion to chondromalacia. Would that be of any assistance to you whether it first came on in [sic] after the '87 incident in the army?
A. It wasn't as severe, probably earlier on.
Q. The chronology February '87 injury in the army. You have been told about the earlier incident in 1980. I would ask you to assume that the plaintiff after 1980 had resumed active sport, was playing cricket, indoor cricket, football and had been selected for a representative team in indoor cricket, and that he and his mother would say that throughout that time they simply cannot recall any such incident as is recorded in the notes of Dr Hemmings, that is not to say that didn't take place, "If it was significant we would have remembered that".
I would ask you to assume at examination involving the assumption you were asked to make about slight crepitus, and movement of the left patella was noted by an army medical officer and in consequence Dr Carter was called upon to examine and express his opinion.
I would ask you to assume that the incident took place in February '87 and that in the two weeks before that the plaintiff had been actively involved in shuttle runs, short runs, sprinting, running formation, a 2.4 kilometre endurance training circuit running and agility over the first two weeks until this incident occurred, he had no problems whatsoever.
I also want you to assume that after the incident in February there was an initial arthroscopy by Dr Huntsdale that makes no reference to any chondromalacia being present, and I ask you to assume later in the same year, May, June, Dr Shannon conducted his arthroscopy again, making no reference to the symptoms of chondromalacia.
What significance are those matters to the opinion you expressed in your report, that in your view the chondromalacia was traumatic and brought about by the incident in the army in 1987?
…
SHORE: Q. Could you answer that question, doctor?
A. I think he was probably recovered from the previous injury when he went to the army, and after the injury he did have some problems with the kneecap and subsequent injury when I saw him and that is what you are seeing.
Q. You were asked some questions by my learned friend about findings in 1997 and you were you say something that might relate to other falls and things that may have occurred in the meantime [sic]?
A. Indeed.
Q. That is your view?
A. That is my view."
69 I have set these passages out at some length, because they are important to the appellant's challenge to the judge's preference for the opinion of Mr Khan over that of Dr Coolican. The appellant said that, on a proper reading of his evidence, Mr Khan agreed that chondromalacia was an ongoing condition likely to have been initiated in 1980 and to have progressed with successive trauma, so that while the 1987 injury was amongst the contributors to the respondent's incapacities it was not the sole cause. It said that although in re-examination Mr Khan considered that the respondent "had probably recovered from the previous injury when he went to the army", that being taken up the by the judge in [51] of his reasons earlier set out, by recovery Mr Khan meant that the condition was lying dormant and not causing any symptoms. It said that Mr Khan's evidence was consistent with the 1987 injury causing the condition to flair up again, and aggravating it, but that the judge was in error in finding that the condition was "attributable to the Army accident alone".
70 In my opinion, the appellant is correct. Mr Khan still did not specifically exclude prior existence of the condition. In my view he accepted that it may have existed prior to the 1987 injury, at one point saying that the respondent "could have had chondromalacia in 1980", at another that he "seemed to be asymptomatic" by 1987. Read as a whole, in particular in the light of his explanation of progressive deterioration with successive traumas between which the condition may be asymptomatic, as applied to young athletic persons, his explicit acceptance that as at 1987 the respondent would not have had a normal knee meant that the knee was affected by the condition.
71 The central element of the appellant's challenge has been made good; with respect, the judge was led into a failure properly to appreciate the evidence of Mr Khan. But it is necessary also to consider the opinions of Mr Beetham and Mr Carter, the common sense considerations and the significance of the 1987 and 1988 arthroscopies.
72 The appellant submitted that Mr Beetham had come to his opinion on an incomplete history, in that the respondent "didn't recover in 1980 at all in terms of there being no further incidents. There were six." Mr Beetham does not seem to have had a history of the later injuries. For the opinions in his reports of 4 July 1998 and 15 April 1992 he did not have the benefit of Mr Khan's observation of chondromalacia, and while he provided a later report dated 1 April 1997 which referred to the arthroscopy performed by Mr Khan he mentioned only the observed tear of the medial meniscus. His statement that the respondent "recovered well from the 1980 incident", whereby he related the condition of the knee "particularly to the incident at the time of his fall on 27.2.97 [sic]", did not address the significance of a series of injuries to earlier development of chondromalacia, and is consistent with asymptomatic chondromalacia as at February 1987. It does not provide a good independent foundation for the condition being "attributable to the Army accident alone".
73 The opinion of Mr Carter, through his investigation in late 1986, was consistent with dormant chondromalacia, as were the beliefs of the respondent and his mother underlying the common sense view taken by the judge. The 1987 injury was correctly seen as a new and significant injury, but it could still be an exacerbation of an existing condition of chondromalacia. To determine whether or not it was required careful examination of the medical evidence.
74 The 1987 and 1988 arthroscopies may be of more significance. The appellant referred to Dr Coolican's evidence that "the diagnosis of patello-femoral pain is very difficult to make", which as I have indicated it equated with chondromalaica, and to Mr Khan's evidence that chondromalacia is "sometimes in the earlier stages not visible to the naked eye" and "may not be visible". I do not think Dr Coolican was directing his mind to observation upon arthroscopy. The chondromalacia observed in November 1993 was described at one point as "fairly advanced changes", but more fully as "fairly extensive but early changes". Observation in 1993 left plenty of time for development of the condition as a result of the injury of 25 February 1987, and if the 1980 injury had initiated its manifestation and it had developed through the subsequent schoolboy injuries, it does not seem that it would be correctly described as in its early stages in 1987 and 1988. The judge was entitled to give weight to a comparison between the chondromalacia observed in November 1993 and the absence of observed chondromalacia in no less than three arthroscopies in 1987 and 1988.
75 Nonetheless, the comparison was not of determinative weight. Dr Coolican referred to improvements in technology: he was not taxed with the comparison, but observed in passing that he did not understand "why nothing was found" in the early arthroscopies - it is not clear that he had chondromalacia in mind. Mr Khan was directly asked whether no observation of chondromalacia in the 1987 and 1988 arthroscopies would be "of any assistance to you whether it first came on in [sic] after the '87 incident in the army". His answer was that "[i]t wasn't as severe, probably earlier on". In short, he accepted that it could have been present but unobserved in an arthroscopy.
76 In my respectful view, on an assessment of the matters to which I have referred, the judge has been shown to have been in error in attributing the chondromalacia entirely to the 1987 injury. On the probabilities, the condition had been initiated in 1980 and had developed, in the manner described by Mr Khan, with the subsequent traumas, and the respondent's knee was not a normal knee as at February 1987.
77 What are the consequences?
78 The appellant had to take the respondent as it found him. If the respondent's incapacity following the 1987 injury is the greater because he did not then have a normal knee, the appellant remains liable in damages for the full extent of that incapacity.
79 The appellant was nonetheless not liable in damages for such of the respondent's incapacity as was wholly or partly the result of the pre-existing chondromalacia or would in any event have resulted from the pre-existing chondromalacia. For this, however, the appellant bore the evidential burden spoken of in Watts v Rake (1960) 108 CLR 158, in which Dixon CJ referred (at 160) to the "presumptio hominis in the plaintiff's favour which any tribunal of fact should insist that the defendant should overcome" and continued -
"If the disabilities of the plaintiff can be disentangled and one or more traced to causes in which the injuries he sustained through the accident play no part, it is the defendant who should be required to do the disentangling and to exclude the operation of the accident as a contributory cause. If it be the case that at some future date the plaintiff would in any event have reached his present pitiable state, the defendant should be called upon to prove that satisfactorily and moreover to show the period at the close of which it would have occurred."
80 In Purkess v Crittenden (1965) 114 CLR 164 it was made plain that Dixon CJ was referring only to an evidential burden: it was said (at 168) -
"We understand that case to proceed upon the basis that where a plaintiff has, by direct or circumstantial evidence, made out a prima facie case that incapacity has resulted from the defendant's negligence, the onus of adducing evidence that his incapacity is wholly or partly the result of some pre-existing condition or that incapacity, either total or partial, would, in any event, have resulted from a pre-existing condition, rests upon the defendant. In other words, in the absence of such evidence the plaintiff, if his evidence be accepted, will be entitled to succeed on the issue of damages and no issue will arise as to the existence of any pre-existing abnormality or its prospective results, or as to the relationship of any such abnormality to the disabilities of which he complains at the trial. It was, we think, with the character and quality of the evidence required to displace a plaintiff's prima facie case that Watts v. Rake was essentially concerned. It was, in effect, pointed out that it is not enough for the defendant merely to suggest the existence of a progressive pre-existing condition in the plaintiff or a relationship between any such condition and the plaintiff's present incapacity. On the contrary it was stressed that both the pre-existing condition and its future probable effects or its actual relationship to that incapacity must be the subject of evidence (i.e. either substantive evidence in the defendant's case or evidence extracted by cross-examination in the plaintiff's case) which, if accepted, would establish with some reasonable measure of precision, what the pre-existing condition was and what its future effects, both as to their nature and their future development and progress, were likely to be."
81 This must be reconciled with an allowance for contingencies, including the contingencies of accident and ill health, in the assessment of damages (see now the principles discussed in Malec v J C Hutton Pty Ltd (1990) 169 CLR 638). If a contingency is known to be greater than normal, that should be taken into account. Applied to allowing for contingencies, the appellant's evidential burden required that it lead evidence capable of establishing the respondent's pre-existing condition and that its ordinary progression and impact may have brought or may yet bring his incapacity. Thus in Wilson v Peisley Barwick CJ said (at 209) that there was no Watts v Rake question because "[t]he existence of pre-existing condition and of its propensity for harm to the plaintiff was fully made out".
82 On any view, the exacerbation of the respondent's chondromalacia in the 1987 injury must have been significant. The respondent was functioning adequately as at February 1987, to the extent that Mr Carter cleared him for entry into the army and he had withstood some weeks of initial training. The appellant accepted that it was a serious exacerbation. The appellant did not lead evidence from which it could be found that the respondent's incapacity was in fact wholly or partly the result of the 1980 injury, or of any particular injury. On the contrary, Dr Coolican was adamant that the contributions of the injuries could not be determined.
83 In my opinion, however, in accordance with the Malec v J C Hutton Pty Ltd principles the chondromalacia should have been taken into account in the allowance for contingencies. The respondent was subject to the ordinary risk of slipping. But from the explanation of the condition given by Mr Khan, the respondent ran a greater risk than most that a slip or slips injuring his knee would bring incapacity, as the slip on 25 February 1987 did. Although Dr Coolican could not determine the contributions of the various injuries to the respondent's incapacity, that an injury such as the 1987 injury could contribute was not in question. The contingency that he might have slipped, or would do so, with injury creating incapacity because he was at greater risk than most, had to be recognized in arriving at his damages.
84 The judge assessed the damages -
general damages $150,000.00
interest on general damages $22,500.00
past economic loss $300,000.00
interest on past wage loss $29,308.00
future economic loss $460,000.00
long service leave entitlement $5,689.00
interest on long service leave entitlement $3,156.00
loss of superannuation benefits $70,000.00
Fox v Wood $58,776.00
past domestic assistance $50,000.00
future domestic assistance $32,000.00
out-of-pocket expenses $166,842.67
future out-of-pocket expenses $100,000.00
$ 1,448,271.67