SUMMARY. Permanent impairment; Osteoarthritis (knee); Tear (ligament).

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1 SUMMARY DECISION NO. 359/95 Permanent impairment; Osteoarthritis (knee); Tear (ligament). The worker suffered a right knee injury, diagnosed as a torn meniscus and a torn anterior cruciate ligament. The worker appealed a decision of the Hearings Officer denying a NEL award. The Board found that the worker's permanent condition was osteoarthritis which was not related to the accident. The Panel found that the accident was a significant contributing factor to the permanent impairment. There was medical support (although not unanimous support) for the proposition that anterior cruciate ligament injuries can be important in the later development of osteoarthritis. The appeal was allowed. [7 pages] PANEL: McCombie; Rao; Meslin DATE: 26/01/96

2 WORKERS COMPENSATION APPEALS TRIBUNAL DECISION NO. 359/95 This appeal was heard in Sudbury on May 17, 1995, by a Tribunal Panel consisting of: N. McCombie: Vice-Chair, M. Meslin : Member representative of employers, F. Rao : Member representative of workers. THE APPEAL PROCEEDINGS The worker appeals the decision of Hearings Officer L. Carr, dated April 8, That decision concluded that the worker was not entitled to a non-economic loss ( NEL ) assessment for his right knee condition. The worker appeared and was represented by G. Hrytsak from the CAW. D. McPhee, the accident employer s claims management supervisor had also intended to participate, but was unable to attend on the day of the hearing. He did, however, make written submissions, dated May 8, THE EVIDENCE The Panel considered the material included in the Case Description prepared by the Tribunal Counsel Office (Exhibit #1). In addition, we considered three Addenda (Exhibits #2 -#4). The Panel also heard oral evidence from the worker. Oral submissions were made by Mr. Hrytsak. As noted, the accident employer s written submissions were also before the Panel. THE ISSUES The Panel must decide whether the worker is suffering from a permanent impairment resulting from his compensable injury. THE PANEL S REASONS (i) Background The worker sustained a compensable injury to his right knee on February 5, He testified that he felt his knee go outside, when he stepped up onto a platform. This platform was approximately eight inches high and he believed that there was a pebble on it which caused the accident. He indicated that his knee twisted when this accident happened. At the time of the accident, he was 60 years old. The initial diagnosis from Dr. M.D. Yankowsky, his family doctor, was internal derangement to rt. knee - meniscus tear quite possible. Further investigation led to the worker s referral to an orthopaedic surgeon, Dr. D. Gordon. On March 26, 1991, Dr. Gordon carried out arthroscopic surgery. His operative report indicates: 1

3 Inspection of the patellofemoral compartment revealed absolutely no abnormalities. Inspection of the medial compartment revealed a very nice looking knee with very little articular damage. He did however have a horizontal and radial tear of the medial meniscus at the junction of the posterior horn with the medial wall of the meniscus. Using multiple munchers the torn piece and flap was removed initially as one piece and then the edges were trimmed. Following this, the residual meniscus was tested for stability and the posterior horn was stable. In light of this it was left intact. Inspection of the notch revealed a torn anterior cruciate ligament. The posterior cruciate ligament was intact. The lateral compartment was excellent. Following this operation, the worker returned to work some time in September He testified that when he returned to work he still felt pain in his knee, and he would get help from co-workers. The evidence indicates that the worker continued to get physiotherapy until December The worker continued to have problems with his right knee. In a letter dated February 13, 1992, Dr. Yankowsky noted ongoing complaints. As a result, the worker was again referred to Dr. Gordon. Dr. Gordon s next report is dated August 10, This report is a significant one which we will quote in its entirety. Before doing so, however, it is important to note that the worker had had complaints concerning his left knee since before the accident. He testified that these complaints were rare and that the problems in his left knee would start at the thigh and radiate over the front of his knee and down to his foot. As noted, this would flare up only on rare occasions. There is a reference in Dr. Gordon s reports to the left knee, although it appears from the context of his reporting that he only dealt with the right knee; that is the knee injured in the compensable accident. Dr. Gordon s August 10, 1992, report reads: Thank you for asking me to see [the worker] again in consultation regarding his right knee. As you know, this man has had problems with his right knee since an injury at work. He underwent an arthroscopic evaluation and medial meniscectomy on March 23rd, He has done reasonably well, although recently, he just started to have recurrent pain in his knee. He is describing recurrent giving way episodes followed by intermittent swelling. He feels a catching sensation under his patella which is associated with a very sharp, knife-like pain which is followed by buckling of his knee. He is still working and has no limitations at work presently. He has had no re-injury that he can recall other than the episodes of giving way. Examination reveals that his right knee has no effusion. He has a click in the patellofemoral compartment. He has pain with patellar compression 2

4 and tenderness with palpation over the medial patellar facet. This reproduces his symptoms actually. He has no pain on the medial side, although he has crepitus in the medial compartment. He has no tenderness on the joint line. He has no varus or valgus instability in flexion or extension. Lachmann and pivot shift were negative. McMurray testing was tender in his medial compartment. He has been on anti-inflammatories which help somewhat but he is still having problems. With lateral pressure over his patella, he had some relief of his patellofemoral discomfort. In summary then, this man presents with osteoarthritis of his left [right] knee. I feel that most of his symptoms presently are coming from his patellofemoral joint. I have given him a prescription for a patellar J- brace and he should wear this and this will hopefully resolve his symptoms nicely. At this point, I would not recommend any further surgery. He may eventually require further evaluation arthroscopically at sometime in the distant future. The worker testified that he has had no other injuries to his knees. He stated that before he could walk long distances, but now could not walk one block without experiencing problems. He has no problems with his other joints. He retired on January 1, (ii) The legal framework Section 42(1) provides that: 42(1) A worker who suffers permanent impairment as a result of an injury is entitled to receive compensation for non-economic loss in addition to any other benefit receivable under this Act. Impairment is defined in the Act as any physical or functional abnormality or loss including disfigurement which results from an injury.... Permanent impairment is defined as an impairment that continues to exist after maximum medical rehabilitation of the worker has been achieved. (iii) The Panel s conclusions As we read the Hearings Officer s decision, he finds that any physical or functional abnormality or loss results from the patello-femoral osteoarthritis and this condition arose independent of the accident. The Hearings Officer relies on the opinion of WCB Regional Medical Advisor, Dr. K. Erola. In a memo dated May 17, 1993, Dr. Erola quotes from Dr. Gordon s August 1992 report, noting that the accident and surgery involved the medial meniscus and that the worker was documented to have fully recovered. This is apparently a reference to a worker s progress report dated September 24, 1991, in which the worker answered the question, What is the present condition of your injury? with the notation full recovery. This report was completed as the worker was about to return to work. 3

5 We note, however, that Dr. Yankowsky, in a report dated that same day, answered No to the question, Complete Recovery Expected?, although he does indicate, but a very good recovery is expected. The worker himself testified that he did indeed continue to feel pain, but felt that he could return to work. Dr. Erola goes on to note, Then a report from Dr. Gordon dated 10 Aug 92 indicated worker having new problems with his knee. As is noted in Dr. Gordon s report cited above, there is no mention of new problems. In fact, Dr. Gordon s first full paragraph notes that the worker has had problems with his right knee since an injury at work. After the surgery, Dr. Gordon reports, the worker had done reasonably well, although recently he just started to have recurrent pain in his knee. The Hearings Officer also found that the arthroscopic surgery did not find a disability in the patello-femoral area. We note, however, that the 1991 arthroscopic surgery did find a torn anterior cruciate ligament ( ACL ). The Tribunal Counsel Office, in noting this fact, included in Addendum #2, an article concerning the relationship between injuries to the meniscus and damage to the ACL. 1 This article notes, at p. 430: Many investigators believe that the projected course of a knee after rupture of the anterior cruciate ligament includes the development of meniscal tears and degenerative arthritis. Others dispute this opinion, stating that the loss of the anterior cruciate ligament could be of no particular importance if the appropriate treatment is followed after the injury. The study carried out by these authors involved younger active athletes and supported the former position, noting: There is ample evidence from our data of the progressive meniscal involvement after an anterior cruciate ligament rupture in the athletically active individuals who continue that lifestyle. Mr. Hrytsak argued that the accident resulted in two injuries: a torn medial meniscus and a torn ACL. The ACL injury, in turn, resulted in an aggravation of an underlying osteoarthritic condition. He noted that there was also osteoarthritis in the left knee, but to a much lesser extent. This would support, he contended, a finding that the accident to the right knee accelerated the development of osteoarthritis at a greater rate than in the left. Mr. Hrytsak pointed to the WCAT Discussion Paper on Osteoarthritis 2. In particular, he noted the answer to question #4 of that paper, dealing with what factors might precipitate the onset of osteoarthritis. The answer makes clear that, in general, osteoarthritis related to trauma develops fairly quickly post-injury and tend to be more unremitting and more steadily progressive. On the other 1 2 Mitsou, A. and Vallianatos, P., Meniscal injuries associated with rupture of the anterior cruciate ligament: a retrospective study in, Injury: the British Journal of Accident Surgery (1988) Vol. 19/No. 5, 429. Harris, W.R. and McCarthy, D.D., June

6 hand, primary osteoarthritis at the worker s age, develops more slowly and is characteristically intermittent. Mr. Hrytsak claimed that the WCB was fixated on the medial meniscus to the exclusion of the ACL tear which, in his view, promoted the osteoarthritis. On balance, this Panel agrees with Mr. Hrytsak s position. It appears to us that there is clear support for a finding that the worker's ACL was damaged at the time of the injury. While the medical community does not appear unanimous in support of the importance of ACL injuries in the later development of osteoarthritis, there is certainly broad support for this proposition. In the case before us, we accept the worker's testimony concerning his left knee and the fact that his right knee had not completely recovered by the time of his return to work. The consequent development of osteoarthritis in the right knee, at a much faster rate than similar changes in the left, supports a finding that the compensable accident was a significant contributing factor in the development of his right knee impairment and therefore subject to a NEL assessment. 5

7 THE DECISION The appeal is allowed. The WCB is directed to arrange for a NEL assessment for the worker's right knee. DATED: January 26, 1996 SIGNED: N. McCombie, M.Meslin, F. Rao 6