Drosd v Workers Compensation Nominal Insurer

Summons

1. The relief claimed in the Summons is as follows: "1. A declaration pursuant to s 69 of the Supreme Court Act 1970 (NSW) that the Certificate and Statement of Reasons issued by the second defendant, constituted by the third defendant, on 6 October 2015, is void and of no effect. 2. An order setting aside the Certificate and Statement of Reasons issued by the second defendant, constituted by the third defendant, on 6 October 2015. 3. An order remitting the matter back to the second defendant for referral to a different Medical Appeal Panel to determine the dispute according to law."
2. Costs were also sought.
3. The Summons went on to identify a number of specific errors, and grounds for the relief claimed.
4. By reference to the submissions which were subsequently filed in this Court, it is apparent that the first basis advanced by the plaintiff for the relief sought is that, in circumstances where the Appeal Panel found that the MAC issued by the AMS contained a demonstrable error, the Appeal Panel did not go on to undertake an assessment in compliance with ss 322, 331 and 376 of the 1998 Act.
5. The second basis for the relief sought is that the Appeal Panel, in proceeding to reassess the degree of whole person impairment affecting the plaintiff's left lower extremity, did so without reference to the requirements of the WorkCover Guides to the Evaluation of Permanent Impairment ("the Guides"), which the Appeal Panel was required to read together with the 5th Edition of The Guides to the Evaluation of Permanent Impairment of the American Medical Association ("AMA-5").
6. The third basis for the relief sought is that the Appeal Panel ought to have, but did not, re-examine the plaintiff in circumstances where the original examination by the AMS had not been conducted in accordance with the requirements set out in the Guides.
7. Finally, the plaintiff submitted that the deduction of 50% made by the Appeal Panel with respect to the pre-existing disability in the plaintiff's left knee was wrong in law.

The Medical Assessment Certificate Issued by the AMS

1. The MAC issued by the AMS was a 10 page document. The AMS noted the documentary evidence which was before him. He then recorded the history that he received relating to the incident and the plaintiff's symptoms. He undertook a physical examination of the plaintiff.
2. The AMS recorded his findings on physical examination, which were as follows: "a. Mr Drosd was of average stature and build. He was overweight and physically very deconditioned. He seemed to be in quite a lot of discomfort, particularly with his right knee. b. Lower limbs. He walked with a slight limp (ironically) of the left leg. Walking on his heels and toes was not effectively possible, nor was squatting. . c. The legs were equivalent in length and in circumference at the calves. . d. The right thigh was 6cm less in circumference than the left. . e. He had extensive surgical scarring over the medial side of the left knee and over the lateral side of the right knee. There was also scarring over the anterior of the right knee. . f. Movement of the hips, the left knee and ankles were relatively normal. Although he had full extension of the right knee, flexion was reduced to 85°. g. There were no significant neurological features."
3. The AMS went on to note the plain x-rays. He provided a summary of the plaintiff's injuries and diagnoses, and noted that the plaintiff gave his accounts of the events clearly and concisely.
4. The AMS then went on to give the following "Reasons for Assessment": "a. My opinion and assessment of (whole person) impairment (1) Right Knee. Loss of useful function of the right leg at or above the knee of 50%. Half of this is due to pre-existing pathology. (2) Left Knee. Loss of useful function of the left knee at or above the knee of 10%. All of this is due to pre-existing pathology. (3) Right Lower Extremity. 'Poor' result (less than 50 points). 30% whole person impairment. (Half due to pre-existing conditions. (4) Left Lower Extremity. 'Good' result. 10% whole person impairment. (All due to pre-existing conditions). b. An explanation of my calculations (1) According to the criteria of Table 17-35 on page 549 of AMA-5, Mr Drosd scores a total of 30 points, giving a whole person impairment for the knee joint replacement on the right of 30%. This is described technically as a 'poor' result. (2) By similar criteria, on the left side the result is technically 'good', giving a 10% whole person impairment. (3) The functional effects of the right leg in its current condition are considered to represent 50% of loss of useful function of the leg. On the left side, the figure is clinically assessed as a loss of useful function of 10%. (4) None of the condition of the left knee is reasonably associated with the event of April 1994. This joint structure was not significantly injured in this event and he has not done anything of significance with this knee to result in gross deterioration which would necessitate the current clinical management. It is therefore considered that the left knee condition is due to pre-existing and unrelated pathology. (5) There is also very extensive pre-existing pathology of the right knee. This is considered to contribute to half of the current condition of the right knee. c. … d. …"
5. The AMS then completed a Table 2 assessment which he stated was "in accordance with AMA-5 and WorkCover Guidelines for the evaluation of permanent impairment for injuries received after 1 January 2002". The MAC was issued pursuant to s 325 of the 1998 Act, and was in the following form: Body Part or system Date of Injury Chapter, page and paragraph number in WorkCover Guidelines Chapter, page, paragraph, figure and table numbers in AMA5 Guidelines % WPI WPI deductions pursuant to S323 for pre-existing injury, condition or abnormality (expressed as a fraction) Sub-total/s % WPI (after any deductions in column 6) Right lower extremity 11/04/94 P 16 Chap 3 P 549 T 17-35 30% ½ 15% Left lower extremity 10% All 0% Total % WPI (the Combined Table values of all sub-totals) 15%

Appeal Panel Reasons

1. The reasons of the Appeal Panel commenced by noting the procedural history up to and including the referral of the Appeal by the Registrar to the Appeal Panel. The reasons noted that a preliminary review was conducted and a determination made that it was not necessary for the plaintiff to undergo a further medical examination. The basis for that determination was as follows: "This is because the Panel is of the view that the material before it is sufficient to enable it both to determine whether a ground for appeal is established and to reassess the medical dispute referred for assessment. In other words, the Panel does not consider that it would obtain any additional useful clinical data from examining the appellant again."
2. The Appeal Panel noted the matters that were referred to the AMS for assessment and the content of the MAC issued by the AMS. It then noted and summarised the submissions made by each party to the Appeal Panel. The Appeal Panel also noted that it had invited the parties to make additional submissions on a question which had been raised for consideration, namely, whether the MAC was a nullity. It determined that it would proceed to determine the appeal, and recorded its findings and reasons. Relevantly, those findings and reasons included the following: "34. It seems to the Panel that the signs the appellant exhibits and the symptoms he suffers currently in his left knee are due to a number of factors. They are the natural progression of the pre-existing degenerative changes in the appellant's left knee as well as to the appellant overloading his left knee joint due to the symptoms he has experienced in his right knee both as a result of the pre-existing degeneration in that knee at the time of injury, and the progression of that degeneration due to both age and the injury. 35. In short, in the Panel's view, the AMS did not properly consider what the effect was of the extra loading on the appellant's left knee due to the extensive degenerative changes in his right knee and consequent symptoms. These symptoms were partly the consequence of the injury the appellant suffered to his right knee on 11 April 1994. The fact that the AMS did not properly consider that factor meant that he both applied a criterion wrongly when assessing the medical dispute insofar as it related to the appellant's left lower extremity, specifically s 323(1), and that consequently the AMS made an error which resulted in the MAC containing a demonstrable error. … 38. In short, the Panel can find no error in the AMS' assessment that a proportion of the appellant's permanent impairment relating to the right knee is due to the previous and extensive degeneration that was existing in the appellant's knee joint prior to his injury. The Panel can also find no error in the AMS' assessment that that proportion is 50%. 39. Hence the Panel does not find any ground for appeal established insofar as the appeal relates to the AMS' assessment of the appellant's permanent impairment relating to the right lower extremity."
3. The Appeal Panel then went on to determine that as there had been a demonstrable error in the MAC relating to the permanent impairment of the plaintiff's left lower extremity "… the Panel must reassess the medical dispute relating to that".
4. The Appeal Panel went on to make these statements and findings: "41. The Panel notes that neither party has raised any challenge to the AMS' assessment that the appellant had 10% whole person impairment relating to the left lower extremity. The controversy between the parties relates to the deduction the AMS made under s 323(1) of the 1998 Act. Given that no challenge was made to that assessment, the Panel adopts it. … 43. In the Panel's view, this evidence indicates that the appellant had extensive osteoarthritis in both joints prior to his injury on 11 April 1994. At that time, the appellant was 37 years of age. The degeneration existing in his knees was far greater than what is normal for someone of comparable age. The view of those members of the Panel who are specialist doctors is that the deterioration of symptoms that is described in the evidence that the appellant has experienced in his left knee after 1994 is the result of the natural progression of the pre-existing degenerative changes to the appellant's left knee, as well as to the appellant overloading his left knee joint due to the symptoms he has experienced in his right knee, both as a result of the pre-existing degeneration in that knee at the time of injury and the progression of that degeneration due to both age and the injury. … It is the clinical judgment of the members of the Panel who are specialist doctors, that a proportion of the appellant's whole person impairment relating to his left lower extremity is due to that pre-existing degeneration and that that proportion is half. … 44. The AMS has made the same error when assessing the impairment dispute relating to the appellant's loss of use of the left knee at or above the knee, as he did when assessing the medical disputes. That is to say, for the reasons provided above, it seems to the Panel that the AMS was wrong to conclude that the proportion to be deducted under s 68A(1) of the 1987 Act was 100%, and ought to have assessed that it was only 50%."
5. The Appeal Panel then went on to issue a new MAC. Insofar as the MAC related to injuries after 1 January 2002, the MAC said this: "This certificate is issued pursuant to s 328(5) of the [1998 Act]. The Appeal Panel revokes the medical assessment certificate of Dr Tim Anderson and issues this new medical assessment certificate as to the matters set out in the table below: Body Part or system Date of Injury Chapter, page and paragraph number in WorkCover Guidelines Chapter, page, paragraph, figure and table numbers in AMA5 Guidelines % WPI Proportion of permanent impairment due to pre-existing injury, abnormality or condition Sub-total/s % WPI (after any deductions in column 6)
6. Right lower extremity 11 April 1994 chapter 3 chapter 17 30% ½ 15%
7. Left lower extremity 11 April 1994 chapter 3 chapter 17 10% ½ 5% Total % WPI (the Combined Table values of all sub-totals) 20%

1. The Appeal Panel concluded its certificate with the following statement: "The above assessment is made in accordance with the WorkCover Guides for the Evaluation of Permanent Impairment for Injuries Received after 1 January 2002."
2. It is convenient at this point, in order to understand the submissions raised by the parties, to refer to the relevant parts of the Guides.

The Guides

1. The 3rd Edition of the WorkCover Guides was published, and took effect, in February 2009. That edition was current at the time of the initial assessment by the AMS and at the time of the assessment by the Appeal Panel.
2. The Guides are issued under s 376 of the 1998 Act. In most cases they adopt AMA-5. Where differences exist between the Guides and AMA-5, the Guides are to be followed.
3. The Guides require the assessment of the level of permanent impairment resulting from work-related injury or disease to be based upon the Guides.
4. Clauses 1.50 to 1.52 of the Guides deal with the question of deductions from whole person impairment assessments for pre-existing condition or injury. Assessors are directed not to include in their assessment of whole person impairment any permanent injury resulting from a pre-existing impairment. That pre-existing impairment is deducted from the whole person impairment existing at the time of the assessment. Clause 1.52 provides for a default deduction. It reads: "1.52 For the injury being assessed, the deduction is 1/10 of the assessed impairment, unless this is at odds with the available evidence."
5. Chapter 3 of the Guides deals with the assessment of permanent impairment of the lower extremities. The Guides provide that Chapter 17 of AMA-5 is to be used for that assessment "… subject to the modifications set out below".
6. Of particular relevance is clause 3.30. It provides: "Note that Table 17-35 (P549, AMA-5) is incorrect. The correct table is shown below."
7. That table is headed "Table 17-35: Rating Knee Replacement Results". It does not need to be reproduced here. What is of significance is that it allocates a number of points to be added together with respect to pain, range of motion and stability. These points are allocated on the basis of a clinical examination undertaken by a specialist. The table then provides that points allocated with respect to "flexion contracture", "extension lag" and "alignment-valgus" are to be deducted from the total points allocated with respect to the first three heads of assessment.
8. In the course of argument, both of the parties accepted that Table 17-35 in AMA-5 differed in content from Table 17-35 in the Guides.
9. The Guides direct that the points allocated in accordance with Table 17-35 are to be converted into a whole person impairment percentage by reference to Table 17-33 of AMA-5. That Table is not amended by the Guides.
10. Table 17-33 of AMA-5 is a particularly long and complex table. Relevantly for present purposes, the table is divided by reference to the region and condition of the impairment. In the case of a total knee replacement, a term which is expressed to include unicondylar replacement, the table provides for the following conversions to whole person impairment: Total Knee Replacement Whole Person (lower extremity) Impairment (%) Good Result 85-100 points 15% Fair Result 50-84 points 20% Poor Result, less than 50 points 30%

1. Attention to these tables demonstrates the following: 1. the initial assessment by reference to Table 17-35 establishes a point score by reference to the six assessed heads of functionality established by clinical examination; 2. that assessed point score enables a categorisation of the result of the knee replacement into one of three identified categories, namely: good, fair or poor; and 3. depending upon the categorisation of the result of the knee replacement into good, fair or poor, Table 17-33 allocates a level of whole person impairment. That level only ranges between 15% and 30%. No other percentage impairment is recognised.

Issue 1: Determination According to Law

1. The plaintiff submitted that the Appeal Panel erred in law when it concluded that the whole person impairment of the left lower extremity after January 2002 was 10%, a figure which was then reduced for pre-existing injury by one half. The plaintiff submits that this was an error for two reasons, namely: 1. 10% whole person impairment is not an available assessment in Table 17-33. That table permits only a whole person impairment ranging between 15% and 30%, depending upon the categorisation of the knee replacement result as good, fair or poor. 2. the Appeal Panel's assessment of 10% whole person impairment for the plaintiff's left lower extremity did not accord with the Guides because the Appeal Panel used Table 17‑35 as it appeared in AMA-5, and not the replacement table found in the Guides.
2. The plaintiff submitted that the nature of these errors is such that either individually or together they constitute jurisdictional error on the part of the Appeal Panel.
3. The Nominal Insurer submitted that there was no error in the particular circumstances here. The Nominal Insurer noted that the Appeal Panel accepted the 10% whole person impairment figure because that was the figure assessed by the AMS in the initial assessment, and that assessment was not the subject of any challenge by the plaintiff in his application to appeal from the MAC.
4. The Nominal Insurer pointed to the provisions in s 328 of the 1998 Act and submitted that, having regard to sub-section (2), the plaintiff is precluded from complaining about the 10% whole person impairment assessment because it was not part of the original appeal to the Appeal Panel.
5. In response, the plaintiff submitted that s 328(2) of the 1998 Act is of no application in circumstances where the Appeal Panel determined that there had been an error by the AMS, and proceeded to reassess the extent of the plaintiff's whole person impairment. In those circumstances, the plaintiff submitted that the Appeal Panel is obliged to undertake its reassessment in accordance with the law, regardless of whether a ground of appeal has raised an error.
6. The 10% whole person impairment figure which is challenged was the figure determined by the AMS. In reaching that percentage impairment, the AMS purported to apply Table 17-33 of AMA-5. He gave no explanation as to the basis for the selection of 10%. On the contrary, he came to a conclusion that the result of the knee replacement procedure on the plaintiff's left side was "technically good", and then assigned the 10% whole person impairment figure. Table 17‑33 obliged him to assign a 15% whole person impairment figure to a result regarded as 'good', on the basis of the points calculated according to (the correct) Table 17-35. Thus, the plaintiff submitted that the assessment of the AMS in this respect did not accord with the law. The AMS was not entitled to find a whole person impairment figure of 10% because that finding was not permitted by the Guides.
7. The assessment of the left lower extremity made by the AMS was adopted by the Appeal Panel.
8. As shown in [30] above, the Appeal Panel determined that there had been a demonstrable error in the MAC "… relating to the AMS' assessment of the appellant's permanent impairment relating to the left lower extremity". The Appeal Panel recognised that its obligation according to law was to "reassess the medical dispute relating to that".
9. It is at this point that the Appeal Panel adopted the assessment of the AMS that the plaintiff suffered a 10% whole person impairment in his left lower extremity. As can be seen above at [32], its reason for so doing was that no challenge had been made to that assessment in the application for leave to appeal to the Appeal Panel.
10. As the new MAC attached by the Appeal Panel to its Statement of Reasons demonstrates, the Appeal Panel purported to review the AMS' finding of 10% whole person impairment by reference to the provisions of Chapter 17 of AMA-5 and Chapter 3 of the Guides. That was its task. It should also be observed that the Appeal Panel, proceeding in accordance with its task, and prior to making its assessment of whole person impairment, revoked the MAC issued by the AMS.
11. The provisions of the 1998 Act require that the Appeal Panel determine whether or not there has been a demonstrable error on one of the grounds specified in s 327(3) of the 1998 Act.
12. Section 328 of the 1998 Act provides that, after undertaking its review, the Appeal Panel: "(5) … may confirm the certificate of assessment given in connection with the medical assessment appealed against, or may revoke that certificate and issue a new certificate as to the matters concerned."
13. Having found error in the MAC issued by the AMS, the Appeal Panel revoked the MAC and determined for itself that the plaintiff's whole person impairment relating to the left lower extremity was 10%. It did so in a shorthand way. That shorthand way was to adopt the assessment of the AMS because no party had challenged it. This shorthand way, whilst arguably permissible, did not relieve the Appeal Panel from its statutory obligation to conduct its assessment according to law.
14. In particular, the Appeal Panel was required to have regard to the provisions of s 322(1) of the 1998 Act in reviewing the AMS' medical assessment. Those provisions require an assessment of the degree of permanent impairment of an injured worker "… to be made in accordance with Workers Compensation Guidelines (as in force at the time the assessment is made) issued for that purpose".
15. That law required the Appeal Panel to apply the Guides, which as I have already explained adopt Table 17-33 of AMA-5. As is evident in [45] above, that Table does not permit an assessment of 10% whole person impairment of the left lower extremity. The fact that there was no appeal against that specific assessment by the AMS is beside the point. Once the Appeal Panel determined to set aside the MAC, it was required to undertake a fresh assessment of the plaintiff's whole person impairment in accordance with the Guides.
16. The Appeal Panel's finding of 10% whole person impairment for the plaintiff's left lower extremity as a consequence of his left knee replacement was not an outcome permitted by, or in accordance with, Table 17‑33 of AMA-5. Nor did the figure reflect an accumulation of points which accorded with a calculation carried out in accordance with Table 17-35 of the Guides.
17. The only conclusion open to this Court is that the assessment by the Appeal Panel of the whole person impairment of the plaintiff's left lower extremity of the plaintiff did not accord with law, and constituted a jurisdictional error. It follows that the MAC issued by the Appeal Panel on 6 October 2015 must be set aside.

Ground 2: Examination of Plaintiff

1. The plaintiff submits that as the MAC issued by the AMS contained internally contradictory findings with respect to the results of the left knee replacement, namely referring to it as either "good" or "poor", the Appeal Panel, in order to assess the resultant degree of whole person impairment once it revoked the original MAC, was required to consider afresh which of the three results contemplated by Table 17-33 applied. In the presence of confusion on the part of the AMS, the plaintiff submits that the only lawful way that the Appeal Panel could have proceeded was to undertake an examination of the plaintiff. The plaintiff submits that as the Appeal Panel did not do so, it did not discharge its statutory duty.
2. In oral submissions in reply, the plaintiff added a further basis for its submission that medical re-examination was required by the Appeal Panel. He submitted that, in circumstances where both the AMS and the Appeal Panel had undertaken their review of the extent of the plaintiff's disability by reference to the incorrect version of Table 17-35, the Appeal Panel, when it came to undertake its reassessment, was obliged itself to examine the plaintiff and to record the requisite points against the correct version of Table 17-35 because, unless it did so, it could not complete that table accurately.
3. The defendant submitted that the description by the AMS of the result of the left knee replacement as both 'good' and 'poor' was simply the result of a typographical error, rather than a substantive error in the reasoning of the AMS.
4. Whilst on its face the report of the AMS does include such a contradiction, it is clear from a reading of the relevant paragraph that a typographical error has been made, and that the 'poor' result was referrable to the plaintiff's right knee and not the left knee. That this is so can be clearly seen by the source of that comment, which is the report of Dr Wallace. An examination of the report of Dr Wallace indicates that at no time was he asked to assess the functional result of the total knee replacement of the left knee. On the contrary, Dr Wallace was only asked to assess, and only carried out an assessment of, the right knee. Any remark by Dr Wallace about the extent of impairment of a lower extremity related only to the right knee.
5. It is clear that a typographical error has been made. It is not a matter of substance. There was no confusion in the Appeal Panel's approach to this matter. It proceeded entirely on the basis that the AMS assessed the result of the left knee replacement as being 'good'. It made its assessment on that basis.
6. The asserted confusion or error did not oblige the Appeal Panel to undertake a physical examination of the plaintiff.
7. There is no jurisdictional error or error of a kind sufficient to give rise to any orders in these proceedings.
8. The submission, raised orally, that the Appeal Panel did not make a lawful assessment because it used the incorrect version of Table 17-35 has greater force. There is a simple attraction to the submission that if the wrong table was used, then another examination would be necessary to enable calculations to be made in accordance with the correct table.
9. This may be correct, but that must depend upon the state of the disability remaining in the left knee. Alternatively, an assessment of the left knee according to the correct Table may not make any difference. These are matters which can only be properly considered by medical practitioners whose expertise is in the clinical examination of a claimant, the obtaining of results of clinical examinations and the interpretation of those results, and whose experience also includes the application of the correct version of Table 17-35. The Court is not in a position to express a firm view that a fresh examination is required in order to enable the assessment in accordance with the correct Table to be completed. It may be entirely possible for an appeal panel, undertaking its assessment in accordance with the law, to reach a conclusion about the point score on the correct Table 17-35 without an examination.
10. In light of my conclusion with respect to the first submission, with the result that the MAC issued by the Appeal Panel will be set aside and it will be necessary for the whole person impairment of the plaintiff to be assessed afresh, no doubt either the AMS appointed to undertake the fresh assessment or, alternatively, the appeal panel appointed to undertake the fresh assessment, will consider whether an assessment of the plaintiff's disability in accordance with the correct version of Table 17-35 can be made without undertaking a physical examination of the plaintiff. It is unnecessary to resolve this submission.

Ground 3: Unlawful Deduction Pursuant to s 323 of the 1998 Act

1. The plaintiff submits that the Appeal Panel erred in assessing the extent of the deduction to be made under s 323 of the 1998 Act with respect to pre‑existing disability.
2. The plaintiff points to the fact that the 50% deduction made by the Appeal Panel on account of the plaintiff's pre-existing injury to his left knee was precisely the same as the deduction made by the Appeal Panel in respect of the plaintiff's right lower extremity. The identity of these deductions led the plaintiff to submit that the Appeal Panel must have ignored a proper assessment of the pre‑existing pathology in both knees because, on any view, it was not identical. The plaintiff went on to submit that it was plain from an examination of all of the evidence that the condition of the plaintiff's right knee prior to the subject injury was significantly worse than that of the left knee. As the plaintiff submitted, the deterioration in the left knee was occasioned by the weakness in the right knee.
3. The plaintiff accepts that there is evidence of left knee degeneration because x‑rays taken in June 1986 confirmed the existence of that condition. As well, there was a history of pain being experienced in the left knee in 1986. However, the plaintiff points to the fact that there is no evidence or history of ongoing or persisting left knee problems, and that the left knee was not treated at any time by Dr Laird, the plaintiffs general practitioner, prior to the subject injury which gave rise to the entitlement to compensation.
4. The absence of any treatment by Dr Laird, at least from 1990 when he took over the care of the plaintiff, was the basis for the plaintiff to submit that, if there was any pre-existing impairment of the left knee, it could only have been minor.
5. The plaintiff submitted that the Appeal Panel had ignored that evidence, had failed to consider its weight when endeavouring to evaluate the pre-injury condition of the plaintiff's left knee and, in the circumstances, that the finding of 50% attribution to pre-existing injury and impairment was incorrect. It was a finding which was not open to the Appeal Panel.
6. The Nominal Insurer submitted that the commencement point of the consideration by the Appeal Panel of the extent of pre-existing impairment for which there is to be a deduction under s 323(2) of the 1998 Act, is that this provision requires an appeal panel to deduct 10% by way of pre-existing disability "… unless this assumption is at odds with the available evidence".
7. The Nominal Insurer submitted that, having regard to the composition of the Appeal Panel, including two approved medical specialists, and having regard to the contents of the Appeal Panel's Statement of Reasons, there is no reason to think that it did not undertake its statutory task as required by s 323, and that the coincidence in finding does not of itself, and without more, demonstrate error.
8. The Nominal Insurer submitted that it was plain from a reading of these Reasons that the Appeal Panel undertook its task fully conscious of its statutory obligations. It reviewed the clinical evidence and history. It highlighted the specific features which provided the basis for its conclusions, and proceeded to express a conclusion. The Nominal Insurer submitted that the mere fact of a coincidence between the two figures in light of the review of the evidence and the findings of the Appeal Panel with respect to that evidence should be regarded by the Court as simply that, namely, a coincidence.
9. The Appeal Panel turned its attention to the issue of assessing the extent of pre-existing pathology in paragraph 42 of its Reasons. It commenced by noting the report of Dr Laird relating to the pre-existing injury to the left knee after the plaintiff had a fall from a ladder on 20 June 1986. It noted the results of x-rays carried out at that time. It also noted that between 1986 and Dr Laird's report of March 1991, the plaintiff had "arthroscopies and other procedures" done to his left knee.
10. The Appeal Panel expressed the view, in paragraph 43 of its reasons, that the evidence indicated that the appellant had extensive osteoarthritis in both joints prior to his injury on 11 April 1994. It concluded that the degeneration existing in his knees was "far greater than what is normal for someone of comparable age". The Appeal Panel went on to say: "The view of those members of the Panel who are specialist doctors is that the deterioration of symptoms that is described in the evidence that the appellant has experienced in his left knee after 1994 is the result of a natural progression of the pre-existing degenerative changes in the appellant's left knee as well as to the appellant overloading his left knee joint due to the symptoms he has experienced in his right knee both as a result of the pre‑existing degeneration in that knee at the time of injury and the progression of that degeneration due to both age and the injury. Given the extent of the degeneration of the left knee joint prior to the appellant suffering injury to his knee joint in 1994, it is the clinical judgment of the members of the Panel who are specialist doctors, that a proportion of the appellant's whole person impairment relating to his left lower extremity is due to that pre‑existing degeneration and that that proportion is half."
11. The Appeal Panel referred to the assumed reduction of 10% for a pre-existing injury or condition in s 323 of the 1998 Act, but stated that it was applying a greater deduction figure because of the evidence before it, which revealed extensive degeneration in the plaintiff's left knee.
12. I can detect no error in the method which the Appeal Panel used to approach this task. It was a matter for medical assessment as to whether the evidence which was relied upon did or did not show that there was pre-existing degeneration and impairment and, if so, the extent of it.
13. If in truth what the Appeal Panel did was to assign an arbitrary figure, then that would not comply with its statutory obligation. However, the way in which the Appeal Panel approached this issue, and the way in which it expressed its opinion and the reasons for it, does not bespeak jurisdictional error simply because the result it reached was coincidentally the same as for the other knee.

Conclusion

1. In summary, I have concluded that the plaintiff has succeeded in persuading the Court that the MAC issued by the Appeal Panel should be set aside for jurisdictional error.
2. In the circumstances, it will be a matter for the second defendant, the Registrar, to determine to whom the impairment dispute should be referred. It is not a matter for this Court to make that determination.
3. However, the second defendant will need to keep in mind that, as the matter presently stands, the original MAC of the AMS has been revoked. That is what the Appeal Panel did. That decision has not been challenged, and stands. Accordingly, there is no existing MAC from an AMS. Nor is there a MAC from the Appeal Panel because this Court has set that MAC aside for jurisdictional error.
4. In those circumstances, it seems to me that there is no extant valid MAC. It will be a matter for the second defendant to consider how the absence of a MAC from either the AMS or the Appeal Panel is to be dealt with.

Costs

1. The appropriate course is that costs should follow the event.

Orders

1. I make the following orders: 1. Order that the Certificate and Statement of Reasons issued by the third defendant on 6 October 2015 be set aside as being contrary to law. 2. Order that the matter be remitted to the second defendant for consideration and decision as to whom a referral ought be made for an assessment of the left lower extremity impairment of the plaintiff in accordance with the law. 3. Order that first defendant to pay the plaintiff's costs.

Amendments 05 August 2016 - Incorrect reference to defendant on coverpage. DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated. Decision last updated: 05 August 2016