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Accident Compensation Cases

Grace v Accident Compensation Corporation (HC, 12/11/04)

Judgment Text

France J
The respondent declined Mr Grace's application for accident compensation following loss of sensation in his right hand after carpal tunnel decompression surgery. The decision to decline was made on the basis that the injury was not caused by medical misadventure. Rather, the respondent considered the symptoms were that of an exacerbation of carpal tunnel syndrome. 
Mr Grace sought a review of that decision. His review application was dismissed on 9 October 2003. Mr Grace then appealed to the District Court. That appeal was dismissed in a decision delivered on 19 March 2004. Another District Court Judge, in a decision delivered on 16 July 2004, refused to grant leave to appeal to this Court. 
Mr Grace now seeks special leave from this Court under s 162 of the Injury Prevention, Rehabilitation, and Compensation Act 2001. That section provides for appeals on points of law. The issue is whether the appeal, if leave were granted, would raise a question of law. 
Doogue J in Impact Manufacturing Limited v ARCIC (High Court Wellington, AP 266/00, 6 July 2001) discussed the approach to the issue of whether leave to appeal should be granted. On the question of what was a point of law, Doogue J noted that a decision-maker's treatment of facts can amount to an error of law. His Honour continued: 
“There will be an error of law where there is no evidence to support the decision, the evidence is inconsistent with, and contradictory of the decision, or the true and only reasonable conclusion on the evidence contradicts the decision: Edwards v Bairstow ([1995] 3 AC 48 at 57). ”
Doogue J cited from Lang v Eagle Airways Ltd [1996] 1 ERNZ 574 at 576 to the effect that if conclusions on the facts were not reasonably open then the Court can rule as a matter of law that they are unsustainable and should be set aside. 
On 16 June 2001, Mr Grace was seen by a Dr M Toes, an orthopaedic registrar, at an orthopaedic outpatient clinic under the supervision of Dr T Love, an orthopaedic specialist. 
On 13 August 2001, Mr Grace had right carpal tunnel decompression surgery undertaken by Dr M Toes. Earlier, in 2000, left carpal tunnel decompression surgery had been successful. 
Mr Grace was later seen by Dr Schaumkel, an orthopaedic registrar, on 10 December 2001. At that point, his forearm pain was reduced but he complained of numbness in the middle and index finger and at the tip of his right thumb. That numbness has persisted. 
On 16 April 2004, Mr Grace was seen by Dr Love. Although it looked satisfactory, the doctor concluded that the relevant nerve was not conducting. He considered that the only option was to re-explore the nerve and on 25 June 2002 Mr Grace had further re-exploratory surgery. Although that surgery resolved the pain Mr Grace had been experiencing, it did not fix the problem of numbness. 
Mr Grace seeks special leave to appeal on the basis that mistakes were made that are evident on the face of the judgment which go to the heart of the causation issue. In particular, it is submitted a question of law does arise on the grounds that, first, the District Court Judge failed to take into account relevant considerations and, second, either relied on irrelevant considerations or made findings unsupported by the evidence. 
As to errors on the face of the decision, the error referred to is the conclusion that the medical evidence supports exacerbation as the more likely cause of the injury. Mr Grace refers in this context to the District Court's acknowledgement during the course of the appeal that the Judge had not read in any detail the medical 4 records containing the medical evidence before him. Mr Grace suggests that the Judge may not have fully grasped the significance of the medical evidence when he did read it. The following evidence is relied on by Mr Grace in this context: 
From the time of the first operation until at least December 2002, no medical authority including Mr Davey was expressing an opinion that the more likely cause of Mr Grace's numbness was the pre-first operation exacerbation. Rather, during this period the medical response was that there was no problem and Mr Grace just needed to be patient and give the first operation time to work. After a scan and nerve test and confirmation of nerve damage by Dr Silverberg, the prevailing medical view prior to the second operation was that something had happened or not happened during the first operation that required further examination. 
Mr Grace then says that during the second operation, Mr Davey extended the area of release in the carpal tunnel area. Immediately following the second operation, Mr Grace says that the continuing pain he had experienced was gone but the numbness that first arose immediately after the first operation continued. 
Mr Grace submits that two critical medical points follow from the above medical information on the file. First, the logical reason for the pain stopping immediately after the second operation is that during that operation Mr Davey completed a carpal release that had not been completed during the first operation by Dr Toes. He says that must be the more likely explanation for the pain going and the more likely outcome that the medical authorities were expecting at the time it was decided to proceed with the second operation. 
Second, while the pain vanished immediately following the second operation, the numbness remained. 
Mr Grace submits that these two pieces of uncontradicted medical evidence shed the greatest light when assessing the more likely cause of the numbness and when assessing the weight to be given to the opinion of Mr Davey. 
Mr Grace argues that Mr Davey's opinion fails to explain why the pain continued following the first operation but ceased after the second. 
Mr Grace next argues that the weight to be given to the pre-first operation pain must be reduced even further when consideration is given to the medical evidence that he had experienced worse episodes of pain much earlier than that which arose two weeks before the first operation. In some cases the earlier episodes of pain/exacerbation were so severe that Mr Grace received cortisone injections. 
The other aspect relied on by Mr Grace is that the District Court Judge stated that Mr MacDiarmid's opinion on the likely cause of his injury had followed an examination of him by Mr MacDiarmid. That was incorrect as no such examination ever occurred. 
The respondent makes two principal submissions. First, that no question of law is raised. Second, that the reference made by the District Court Judge to Mr MacDiarmid examining Mr Grace does not raise a question of law capable of serious and bona fide argument but rather is a question of the weight to be given to his evidence. 
In expanding on the first submission, the respondent notes that Mr Grace appears to accept that the correct legal test was identified by the Court. That is, that to succeed in the appeal Mr Grace has to establish on the balance of probabilities that his disability (the numbness or nerve damage) has resulted from the surgery. Rather, Mr Grace appears to claim that the Court erred in the way it addressed the evidence before the Court in order to determine the issue of causation. 
Although it is accepted that a decision-maker's treatment of the facts can amount to an error of law as explained in Impact Manufacturing, this is only where there is no evidence to support the decision or where the conclusions reached were not reasonably open on the evidence. Here, it is the Court's assessment of the evidence which is being challenged and this does not raise a question of law. 
It is further submitted that the evidence addressed the correct question, that is, causation and that not only was the Judge's finding open to him on the medical evidence but it was wholly consistent with that evidence. Indeed, the medical evidence on which Mr Grace relies does not establish a causal connection with the surgery but, at most, it is submitted is inconclusive. 
On the second aspect, that is Mr MacDiarmid's evidence, it is accepted that Mr MacDiarmid did not personally examine the appellant. Rather, he was asked to provide an independent opinion on the claim for medical misadventure. But, the respondent says, nothing turns on this error. That is because this is not a situation where there is a conflict of medical evidence and so Mr MacDiarmid's comments were not relied upon to resolve any such conflict. Rather, this was one piece of evidence and it supported the evidence provided by Mr Davey. This is a question of weight, not law. 
District Court Judges' decisions 
In the substantive decision, the District Court Judge discussed the history of the matter, the appellant's case, and the relevant legislation. The Judge stated that to succeed in the appeal,  
“the appellant has to establish on the balance of probabilities that his disability has resulted from the surgery. There has to be a pathological causal nexus between the surgery and the present disabilities. The information in front of me indicates two possible scenarios: 
that the present disabilities relate directly to the exacerbation of carpal tunnel compression which occurred in the two to four weeks prior to the surgery of 13 August 2001; or 
that the present symptoms are a direct consequence of the surgery. In this latter regard, the coincidence between the onset of the symptoms and the surgery is relevant. ”
(para [22])
The District Court Judge's conclusion was that the medical opinion all supports the first scenario. The Judge considered the fact that Dr Toes may have experienced difficulties during the operation did not necessarily mean that medical mishap occurred. Similarly, the fact that the doctor in his report confused which hand he had operated on did not really help to establish medical mishap. However, the Judge continued: 
“The pre-operation exacerbation of pain, coupled with the excessively flattened median nerve noted throughout the whole process, constitutes strong evidence against the medical mishap scenario. Finally, Millar v ACC (197/02) is authority for the proposition that coincidence on its own is insufficient to establish a causal nexus. ”
(para [26])
Accordingly, the Judge concluded that Mr Grace was not able to establish on the balance of probabilities that his present complaints were caused by the surgery. 
In the decision declining to grant leave to appeal, the District Court Judge considered the background facts and the earlier decision of the District Court. The Judge then set out the appellant's submissions. 
The Judge noted that the issue of causation is a question of asking, first, the correct issue of law and then determining the factual issues against the legal test of causation. The District Court Judge considered that in the earlier decision, the question of law was correctly posed and then the factual issues were tested against that legal issue. Having then considered all of the medical evidence, the District Court Judge concluded:  
“I cannot see any strong statements from either Mr Love or Dr Silverberg establishing the causation test on a probability basis. There is the strong medical opinion of Mr Davey and Mr McDiarmid against a causal link. 
In my view, there is not even really a medical conflict. The appellant here is seeking to take passages out of the medical opinion of Mr Love and Dr Silverberg, and argue against the conclusions of Mr Davey and Mr McDiarmid. ”
The Judge could not see there was an issue of law arising sufficient to state for the High Court. The correct legal test was put forward and there was sufficient medical opinion upon which the Judge could base his decision. The evaluation of medical evidence is essentially a question of fact. 
Section 20 of the Injury Prevention, Rehabilitation, and Compensation Act 2001 provides there is cover for personal injury if that injury is caused by medical misadventure. Section 32 states that “personal injury caused by medical misadventure” means personal injury that is suffered by the person seeking or receiving treatment and is “caused by medical error or medical mishap”. Medical error is defined as meaning “the failure of a registered health professional to observe a standard of care and skill reasonably to be expected in the circumstances” (s 33). A medical mishap is defined as a severe adverse consequence of treatment resulting in the suffering of a restriction or lack of ability that is significant, which prevents the person from performing an activity that is considered normal for that person, and lasts for more than 28 days in total. A medical mishap only occurs if the probability is that the adverse consequence is rare, that is, it would not occur in more than one percent of cases in which that treatment is given (see s 34). 
Here there is no question of medical error but Mr Grace alleges medical mishap. The question for the District Court Judge was whether Mr Grace was entitled to cover for the numbness he experienced. This turned on whether there was a causal link between that condition and the first surgery. 
As Mr Grace put his case at the hearing, it is that the District Court Judge's decision comes within the Edwards v Bairstow test for an error of law. In particular, the conclusion drawn by the Judge was not reasonably open on the facts. Mr Grace emphasises the following matters: 
For the first 16 months after his initial operation, none of the medical people suggested the numbness resulted from pre-operative exacerbation. 
His pain ceased after the second operation and Mr Davey does not explain why the pain continued up to that point. 
The numbness remained. 
His pain was not as great in the two weeks prior to the first operation as it had been earlier. 
There was no evidence of nerve atrophy until after the first operation. 
The Judge may have been influenced by his mistaken belief that Mr MacDiarmid had seen the appellant. 
In considering whether there is a point of law raised by these matters, it is necessary to consider the medical evidence and I now set that out. 
When Dr Toes first saw Mr Grace on 16 July 2001, his notes included the following:  
“He now presents with increasing tingling and numbness in the index to ring fingers with increasing frequency. …  
On examination he has some mild right thenar eminence wasting. There is a subjective sensory deficit to light touch over the index to middle fingers. Phalen's and Tinel's tests are negative. ”
The operative record from Dr Toes dated 13 August 2001 notes that Mr Grace had severe bilateral carpal tunnel syndrome. In terms of the procedure he followed, Dr Toes noted that the “Median nerve found tightly trapped in the canal and markedly flattened” and the nerve was decompressed. The notes record his “check” that “full decompression achieved”
The outpatient's report for 24 August 2001 records that Mr Grace was seen by Mr Love one week after his right carpal tunnel release. The notes record Mr Grace had quite a lot of forearm pain since his surgery. The notes continue: 
“However on questioning him further he did admit that for the two weeks prior to coming in for his carpal tunnel he had exactly the same type of pain which was also very severe. ”
Mr Love noted that the wound had healed well and the daytime numbness and tingling had settled “dramatically”
It is relevant that although Mr Love thought, as Mr Grace says, that things would settle down, Mr Love was also at this early stage making some reference to the severity of the pre-operative pain. 
On 10 December 2001, Mr Grace was seen by Dr Schaumkel at Mr Love's clinic. This was then some four months following his right carpal tunnel release. Dr Schaumkel noted that the follow-up pain had resolved “a lot” but Mr Grace was “still complaining of marked numbness involving his middle and index fingers and the tip of his thumb.” 
Dr Schaumkel said he discussed the case with Mr Love and that Mr Grace was referred for nerve conduction studies. 
Mr Grace saw Dr Silverberg, a neurologist, on 6 March 2002. Dr Silverberg's notes record that in March of 2000, Mr Grace had decompression of his left median nerve at the wrist for carpal tunnel syndrome. He continued having pain and numbness in his right hand. The pain was very severe in July 2001. On 13 August 2001 he had a release of his right median nerve at the wrist. Dr Silverberg notes Mr Grace's recollection that there seemed to be “some difficulty” with the surgical process done under local anaesthetic. Dr Silverberg continued: 
“Within a month of the surgery he was aware that he had constant numbness in the distribution of the right median nerve. He has also noted severe atrophy of the thenar muscles. He is unable to do up buttons and trim his toe nails. The problem is not improving and it does cause him a lot of frustration. … He believes that at the onset there was some numbness on the dorsal aspect of his thumb, index and middle fingers but this numbness has cleared. ”
On examination, the doctor noted that there was severe atrophy of the right thenar muscles and that Mr Grace was unable to abduct his right thumb. Further, he had severe numbness in the median distribution including the median half of the ring finger. 
The doctor said that this was certainly something “we would not expect” after carpal tunnel surgery. 
Mr Grace was seen next by Mr Love on 15 March 2002. Mr Love noted Mr Grace's distress at his right hand function. Mr Love noted also the marked atrophy of the thenar muscles but a reasonably well healed scar. Further, there was significant sensory disturbance with almost absent sensation in the median nerve distribution. The notes continue:  
“I have told Mr Grace that he has developed seemingly two problems. He certainly now clearly has developed a reflex sympathetic dystrophy type problem. I attempted to explain what this is and that it is a rare complication of surgery procedures and/or injury. … He also appears to have no conduction through the median nerve at all. Occasionally this can be seen with severe atrophy of the nerve in that even decompressing the nerve does not result in resolution of the internal derangement of the nerve. Mr Grace points out that he did not have significant symptoms prior to having his carpal tunnel release but the fact of the matter is that at surgery it was observed the nerve was atrophied. ”
The radiology report of 26 March 2002 found that the median nerve appears flattened as it passes through the carpal tunnel. 
When Mr Grace was seen again on 15 April 2002 by Mr Love after his MRI scan, Mr Love noted that the scan had shown slight flattening of the nerve but the nerve appears to be in continuity with no evidence of iatrogenic injury to the nerve. Mr Love thought this was a “most puzzling” situation. “Mechanically and anatomically” the nerve looks “fine” but it is not conducting. Mr Love said he was at a loss to explain the lack of median nerve function and the only option faced was the possibility of re-exploring the nerve. 
Mr Grace was then seen by Mr Davey on 10 June 2002. The notes record that it would appear from Mr Grace's history that he had quite severe carpal tunnel syndrome pre-operatively and this was confirmed at surgery by the gross appearance of the tight tunnel and marked flattening of the nerve. The notes continue: 
“I explained to Mr Grace that sometimes the median nerve does not recover completely when it has been severely compressed and some residual loss of sensation and muscle power occurs. However the MRI appearance of a thickened, reconstituted flexor retinaculum raises the question as to whether there is still some residual compression and the only way of determining this would be by a further decompression, …  ”
Mr Davey's operative record of 25 June 2002 refers to the re-exploration which then took place. The record of this exploration notes that there was an area of marked indentation and flattening of the median nerve and that in this area the nerve was narrowed down and looked atrophied. 
Mr Grace was then seen by Mr Davey on 8 July 2002. In relation to the reexploration operation, Mr Davey noted that Mr Grace was found to have quite marked narrowing of the median nerve in the carpal tunnel over an area of about 1.5cm. Apart from this there was no sign of any previous surgical trauma to the nerve. 
Mr Grace was then seen by Dr Singh on 19 August 2002. He was seen again by Mr Davey on 26 August 2002. Mr Davey noted Mr Grace's disappointment that since the re-exploration there had been no recovery in the quality of sensation nor in the feeling of weakness in his right hand. On the positive side he had complete relief of his pain symptoms. Mr Davey had had a long discussion with Mr Grace about the sequence of events surrounding his right carpal tunnel syndrome. Mr Davey noted there was no mention of anything untoward in the operation notes and that at the time of re-exploration there was also no sign of anything untoward which may have occurred at the operation. There was however marked narrowing over a small section of the median nerve which is a common finding in quite marked carpal tunnel syndrome. 
When seen again by Mr Davey some six months after the re-exploration (on 16 December 2002), Mr Davey noted Mr Grace's view that there was no recovery in the quality of sensation. 
On 1 May 2003, Mr Davey prepared a report for the respondent. The report sets out the background noting that there is no record of any untoward event occurring during the first operation. Mr Davey then discussed his involvement and Mr Grace's subsequent care. In terms of the re-exploration, Mr Davey noted there was no evidence of any surgical trauma to the nerve and nor was there any sign of residual compression, that is, the original release procedure appeared to have been “perfectly adequate”. Importantly, in my view, is this comment from Mr Davey's report: 
“Although Mr Grace maintains that he did not have significant loss of sensation prior to his surgery, it is clearly recorded in Dr Toes's initial assessment notes that there was subjective loss of sensitivity. It is apparent from Mr Grace's own history that between the time of that initial assessment and his operation four weeks later that he had very marked increase in severity of the pain associated with his carpal tunnel symptoms and I suspect that this pain, to some extent, masked the severity of the sensory loss which almost invariably accompanies severe carpal tunnel syndrome. It would certainly be very unusual to have the degree of flattening of the median nerve which was observed by both Dr Toes and myself, without very significant sensory loss. I feel that it was only when the majority of his pain was relieved by the initial decompression that Mr Grace became aware of the sensory loss, which I believe would have developed pre-operatively. 
In summary I feel that Mr Grace is unfortunate to have suffered from a severe acute exacerbation of carpal tunnel compression immediately prior to his release operation on 13.08.01 and that his ongoing numbness is due to a degree of permanent damage to the nerve caused by this compression and that there is no evidence of medical mishap relating to the procedure on 13.08.01. ”
Dr Riddell on 15 June 2003 wrote to the respondent attaching Mr Grace's clinical notes. His letter confirms that on earlier occasions, the pain was such that Mr Grace was given cortisone injections. Dr Riddell also said: 
“I do not feel that the nerve was damaged at surgery, but am not sure whether full decompression was achieved. The second operation appears to have eased the pressure on the nerve but Mr Grace is left with definite weakness in the hand. He still feels that the sensation in the hand is not as good as it had been, although clinically this is not so obvious. However there is a definite weakness remaining in the hand. ”
Finally, reference should be made to the review by Mr MacDiarmid the orthopaedic surgeon. The report of that review is dated 26 June 2003. It sets out the background facts and then concludes as follows: 
“The findings at surgery were of a severely compressed median nerve. There were no untoward events occurring during surgery or postoperative recovery and further surgical exploration confirmed that the nerve was intact but it was tightly compressed. It is also clear that Mr Grace's condition deteriorated in the 4 weeks prior to surgery with significant exacerbation of symptoms. 
I would advise that this claim be declined as there is no evidence that medical mishap occurred during the carpal canal decompression. There is adequate evidence confirming that the nerve was quite severely compressed and that exacerbation of compressive symptoms occurred weeks prior to surgery. Both of these factors are more likely to be the cause of persisting postoperative numbness in the fingers of the right hand. There is no evidence that injury to the nerve occurred during the index operation. ”
Reviewing the evidence, I consider it was a reasonable conclusion that Mr Grace's present disabilities relate directly to the exacerbation of carpal tunnel compression which occurred in the two to four weeks prior to the initial surgery. Even putting Mr MacDiarmid's report to one side, that conclusion was open on Mr Davey's evidence. Mr Grace's view is that decompression and flattening are common with carpal tunnel and that the exacerbation referred to boils down to a question of pain. However, that is not what the medical evidence says. 
I deal then with the various matters relied on by Mr Grace in turn. 
First, in terms of the medical experts' initial response, there is the reference I have noted before to Mr Grace experiencing severe pain prior to the first operation. I acknowledge that the possibility of some residual compression is raised by Mr Davey in his notes of 10 June 2002. That is probably the best evidence of Mr Grace's argument that, as he put it, this was a job only half done at the first operation. However, the reality is that the medical people could not be sure without further exploration having been undertaken as to exactly what the position was. Hence, Mr Davey after re-exploration, said:  
“Nevertheless the question as to whether there was still some residual compression due to incomplete depression at the time of his initial surgery or the possibility of surgical damage to the median nerve at that initial procedure, could not be determined with any certainty without further surgical exploration of the nerve. Therefore it was decided, with Mr Grace's consent, to go ahead with re-exploration of the median nerve. … [With reference to the re-exploration Mr Davey continued] There was no evidence of any surgical trauma to the nerve, nor was there any sign of residual compression, i.e. the original release procedure appeared to have been perfectly adequately. ”
Second, in terms of the pain relief which followed the second operation, the issue before the District Court was related to the numbness. Ms Ahern is correct that the possibility that Mr Davey in re-exploration may have improved matters does not necessarily mean there was a problem with the first operation. In any event, the fact that, as Mr Grace put it, full decompression was eventually done and so supporting the view it could have been done originally, is not the critical point. More important is Mr Davey's conclusion that the initial decompression was “perfectly adequate”
Third, with reference to the numbness, the District Court Judge accepted that the appellant was unaware of the loss of sensation at the earlier time but said that the increased pain may have obscured this. There is evidence of some earlier sensory problems but the medical evidence is that the pain probably masked that. 
Fourth, in terms of the extent of pain pre-operation, I note that Mr Davey refers to a very marked increase in the pain prior to the operation. Again, the evidence is there for the conclusion drawn. 
Fifth, there is the question of atrophy. Mr Grace points to Dr Toes' note of 16 July 2001 which states that Phalen's and Tinel's tests are negative. However, I note that in Mr Davey's notes of 10 June 2002, Mr Davey states that Phalen's test “did not seem to make [Mr Grace's] numbness any more profound” and even at that stage, Tinel's test was negative. Accordingly, I doubt much can turn on those test results. Further, Mr Grace accepts that atrophy would not develop overnight and so it is perfectly possible that the process of atrophy was triggered by some earlier event, that is, other than the operation. 
Finally, in terms of the Judge's reference to Mr MacDiarmid having seen Mr Grace, I agree this is not very helpful. In the end however I do not see it as giving rise to any question of law capable of a bona fide argument. It is, at the end of the day, a matter of the weight given to Mr MacDiarmid's evidence. Given the strength of the other evidence, particularly that of Mr Davey, I just cannot see this point as giving rise to a question of law. 
Mr Grace, having been awake at the time of the first operation, reached the view that something had gone wrong. The resultant frustration when matters did not improve in terms of numbness after the second operation is very real and understandable. It is also not helpful from Mr Grace's point of view that it was not possible to have direct evidence from Mr Toes. That may have been able to clarify matters for Mr Grace. However, it is clear to me that the Judge has drawn a reasonable conclusion from the available evidence. The argument really is about that factual assessment made by the Judge and Mr Grace's preference for a different assessment of that evidence. That is not a question of law in the present case. 
The application for special leave is accordingly declined. 
The respondent did not seek costs in the event leave was declined. Costs therefore lie where they fall and no order as to costs is made. 

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