WORKPLACE SAFETY AND INSURANCE APPEALS TRIBUNAL DECISION NO. 2464/03

Transcription

1 WORKPLACE SAFETY AND INSURANCE APPEALS TRIBUNAL DECISION NO. 2464/03 BEFORE: T. Carroll: Vice-Chair G.V. Stewart: Member Representative of Employers D. Gillies: Member Representative of Workers HEARING: December 17, 2003 at Thunder Bay Oral Post-hearing activity completed on August 19, 2005 DATE OF DECISION: November 28, 2006 NEUTRAL CITATION: 2006 ONWSIAT 2788 DECISION(S) UNDER APPEAL: WSIB ARO decision dated May 17, APPEARANCES: For the worker: For the employer: Interpreter: Mr. G. Sirois, Office of the Worker Adviser Mr. W. Lemay, Lawyer Not applicable Workplace Safety and Insurance Appeals Tribunal Tribunal d appel de la sécurité professionnelle et de l assurance contre les accidents du travail 505 University Avenue 7 th Floor 505, avenue University, 7 e étage Toronto ON M5G 2P2 Toronto ON M5G 2P2

2 Decision No. 2464/03 REASONS (i) Issue [1] The Panel has to determine whether the worker is entitled to a pension assessment (either a permanent disability or permanent impairment assessment) of his left knee. (ii) Background [2] The Panel s findings of fact in regard to the background in regard to the worker s knee injuries and related medical treatment during the time period from 1979 to the date of the hearing in 2003 are contained in Tribunal Decision No. 2464/03I. [3] The background facts contained in Decision No. 2464/03I outline the worker s injuries and treatment in regard to both his right and left knee. [4] For ease of understanding, the Panel felt it would be of benefit if injuries and treatment in regard to the worker s left knee were repeated in this decision. [5] On October 13, 1982 the worker, a police officer, injured his left knee while lifting an intoxicated person. The worker sought medical attention on October 14, The diagnosis was left knee pain and the worker was instructed to ice and elevate the leg. The worker did not lose time from work due to this injury. [6] On December 15, 1983 the worker, now a patrol sergeant, twisted his left knee while arresting a person. The worker sought medical attention from his family physician Dr. V. Zaitzeff on December 15 th. The diagnosis was a sprained ligament of the left knee. The doctor applied a tensor bandage and recommended rest. An x-ray of December 20, 1983 showed no evidence of a fracture. On December 27, 1983 Dr. Zaitzeff diagnosed a sprained quadriceps tendon of the knee. The worker returned to his regular job duties on January 3, [7] On July 8, 1991 the worker was carrying a 40 pound portable television set down a steep flight of stairs when his right knee buckled and he favoured his left knee while executing the remaining stairs. The initial diagnosis was quadriceps tendonitis. On July 12, 1991 Dr. A. Porter, orthopaedic surgeon, diagnosed a partial rupture of the left quadriceps tendon. [8] The worker s left leg was placed in a cylinder cast. The worker s leg continued to remain in a full cast to August 1991 when he began physiotherapy. Physiotherapy continued from September to November The worker returned to modified light duties, four hours per day, on October 15, The worker returned to full time regular duties on November 18, [9] In late July 1994 the worker was seen in the emergency department of a hospital. The worker s left toe was lanced due to an apparent abscess. The worker was followed by Dr. Porter due to acute redness in the left knee and the worker s left toe difficulties. Dr. Porter believed the worker s right knee problems were due to extensive chondrocalcinosis. He felt the worker may be developing recurrent crystalline synovitis in both knees.

3 Page: 2 Decision No. 2464/03 [10] In October 1994 the worker reported problems with both knees when walking, driving or when there was damp weather. The worker also testified that going up and down stairs and carrying out the activities of daily living bothered both knees. [11] On January 18, 1995 the worker advised his employer that his right knee gave out going down stairs while at work and he put force on his left knee causing pain. The worker was seen in the emergency department of a hospital on January 18 th with a slightly swollen left knee and pain along the medial aspect of the left knee. The diagnosis was a left knee strain. [12] Dr. Zaitzeff saw the worker on March 13, 1995 in regard to his January 1995 accident. He diagnosed a strained lateral collateral ligament and a possible torn meniscus. The worker was off work from March 1st to March 9 th, [13] On April 7, 1995 the worker fell on ice while at work and felt pain in his left knee. The worker saw Dr. Zaitzeff on the same day and the diagnosis was a sprained ligament of the left knee with left collateral ligament pain. The worker was off work from April 7, 1995 to April 22, [14] In June 1995 Dr. D. Cadman, Medical Consultant at the Board, considered the worker s injury claims in January 1995 and April Dr. Cadman noted that the worker had problems in his left knee with gouty arthritis and it would flare with minor incidents. Dr. Cadman felt the worker could be paid on an aggravation basis (aggravation of the gout) and the worker should be considered at his pre-accident state in regard to the January incident. He felt the April 7 th incident was minor but it also could have caused the gouty arthropathy to flare up. The Board, based on Dr. Cadman s opinion and a subsequent medical opinion of Dr. J. Hignell, Medical Consultant at the Board, paid the worker lost time benefits from March 1, 1995 to March 9, 1995 and April 7, 1995 to April 22, The Board determined that the worker had recovered from these incidents when he returned to his regular job duties. [15] The worker s next medical attention for his left knee was on December 5, 1995 at the Port Arthur General Hospital. The worker complained to his employer that both knees were sore and swollen and these problems appeared to be in relation to the weather. The worker went off work on December 5 th. On December 19, 1995 the worker reported that both knees continued to swell and be sore without any precipitating event. [16] On January 26, 1996 the worker was seen at the hospital with pain in both knees with no precipitating event. The worker saw Dr. Zaitzeff on February 7 (pain in both knees) and February 19, 1996 (pain in left knee) and the worker was advised to discontinue working. The cause of the worker s left knee problems was noted as being walking while on duty. The worker saw Dr. Porter on February 7 th due to left knee problems unrelated to trauma. The pain could come on while sitting. Dr. Porter arranged for steroid injections. The injection helped to bring down the swelling in the left knee. On April 10, 1996 Dr. Porter saw the worker again in regard to his left knee difficulties and felt they may be related to crystalizing synovitis such as gout or degenerative arthritis in association with a degenerative medial meniscus tear.

4 Page: 3 Decision No. 2464/03 [17] Dr. Porter s arthroscopy examination results of the worker s left knee showed tremendous chondrocalcinosis with the articular surface covered with calcific deposits. There was no evidence of a torn meniscus. [18] In May 1996 Dr. J. Hignell of the Board reviewed the worker s file and opined that the worker was not entitled to benefits for lost time from work in 1996 as the worker s left knee was not aggravated at work and treatment was directed at the worker s pre-existing condition (gout). Dr. Hignell felt the worker was not entitled to a permanent disability award under the October 13, 1982 and December 15, 1983 claims. Dr. Hignell repeated his opinion in August He stated that the worker had recovered from the aggravating left knee incidents in 1995 and his subsequent left knee problems appeared to be gouty arthritis which was a noncompensable but could be triggered by trauma. [19] On July 17, 1996 the worker saw Dr. J. Roddy, a rheumatologist. Dr. Roddy had seen the worker in 1994 with a painful left great toe. The toe was aspirated and the worker had multiple uric acid crystals. At this visit the worker reported that he had left knee problems for one year. Aspiration of the left knee showed the presence of multiple monosodium urate crystallizing consistent with an acute attack of gouty arthritis. Dr. Roddy stated trauma may be a provocative factor in initiating acute gouty attacks. [20] In March 1999 Dr. W. Fidler, a rheumatologist, opined that the worker had degenerative arthritis of both knees. He felt the worker s knee problems resulted from his previous injury. It should be noted that Dr. Fidler believed, incorrectly, that an injury to the worker s right knee in May 1994, that resulted in a subsequent arthroscopy, was in relation to the worker s left knee. In November 1999 Dr. Fidler stated that he believed the worker was suffering from osteoarthritis of the left knee and the injury of 1991 and perhaps previous injuries were the causes. Dr. Fidler believed the worker s crystal arthritis was more probably related to injury rather than CPPD disease based on the worker s age. [21] In June 2001 Dr. G. Wentzell, Medical Consultant at the Board, reviewed the worker s file and concluded that there was no causal relationship between the worker s left knee problems and his June 1991 accident when the worker suffered a partial tear of the quadriceps tendon. (iii) The medical reports of Dr. A. Gordon, Rheumatologist and Professor of Medicine, University of Toronto [22] Due to the medical complexity of the case, the Panel forwarded all case record material together with Decision No. 2464/03I to Dr. D. Gordon, Tribunal Medical Assessor, for his medical opinion in regard to various medical issues and concerns. [23] The Panel s concerns were expressed in a number of questions forwarded to Dr. Gordon. Dr. Gordon, before offering his opinion, requested further medical information not contained in the file. This medical information was obtained through the Tribunal Counsel Office and included x-rays of the worker s hands, knees, ankles and feet taken in May The x-rays showed that the worker had minimal osteoarthritis of the fingers of his hands, minimal arthritis of both knees and minimal osteoarthritis of both feet. [24] The Panel s questions and Dr. Gordon s reply are noted below.

5 Page: 4 Decision No. 2464/03 [25] 1. Please provide your differential diagnosis of this worker s left knee condition. In your opinion, what is the most likely diagnosis? Please explain the reasons for your opinion. The diagnostic considerations are gouty arthritis, calcium pyrophosphate dihydrate (CPPD), crystal deposition disease (pseudogout), rheumatoid arthritis, and osteoarthritis Gouty Arthritis Gout is a disease resulting from tissue deposition of crystals of monosodium urate leading to recurrent attacks of gouty arthritis, accumulation of crystalline deposits called tophi, and often uric acid calculi in the urinary tract. This condition has a strong hereditary component in keeping with [the worker s] family history of gout. However, there are multiple environmental influences governing manifestation of the disease in addition to genetic factors. These factors include body weight, diet, alcohol, medications, and trauma. The stages of the disease include an asymptomatic interval for many years followed by intermittent inflammatory attacks commonly affecting one or other great toe. In [the worker s} case, he would fit into the category of polygout or polyarticular gout since he has had a number of joint areas affected, such as the knees, elbow and ankle, and after 10 or more years of intermittent gout, persistent swelling related to topaceous deposits of monosodium urate coming on about a decade or more after the onset of acute episodes. In my view, the calcific deposits, described by Dr. Porter at arthroscopy March 15, 1996, were those of urate crystalline material, in keeping with tophaceous gout also affecting his left great toe. Provocative factors of acute attacks include trauma, which may be as minor as a long walk, without causing pain during the activity, but later at rest, leading to gouty attacks commonly occurring at night. Drinking alcohol, that [the worker] stopped more than a decade ago, may predispose to gout through several mechanisms, since ethanol can raise uric acid production. Medications such as diuretics may also precipitate gouty attacks, as can low doses of Aspirin. Ordinarily, gouty attacks can be controlled and prevented by two forms of medication, first Allopurinol, and second Sulfinpyrazone. It is clear form the documentation that at times [the worker] tried taking Allopurinol, but Dr. Fidler, in his report of January 30, 1997, makes this comment, he has tried Allopurinol in the past, but did not tolerate this. It is not documented whether he now takes it or not.

6 Page: 5 Decision No. 2464/03 CPPD Crystal Deposition Disease This disorder can be hereditary or associated with various metabolic diseases or trauma. These metabolic associations, for example, include hyperparathyroidism, hemochromatosis, and hypothyroidism, as well as aging and diabetes mellitus. The typical radiologic feature of this condition is the typical appearance of linear densities in articular hyaline or fibrocartilaginous tissues. Radiologic appearance is specific. Basic calcium phosphate can also produce a radiologic appearance, and shards of hydroxyappetite crystals can initiate an inflammatory response by interaction with other crystal surfaces such as monosodium urate and CPPD. The presence of soft tissue calcium reported in the X-ray of December 12, 1994, I believe, would be compatible with such a mechanism since the soft tissue deposition is not characteristic of CPPD crystal disposition disease. Otherwise, he has no metabolic factors that would cause CPPD. Rheumatoid Arthritis This is a chronic inflammatory disease that produces persistent and progressive inflammation in peripheral joints. These joints, unlike [the worker s] are, affected in symmetrical fashion, affecting upper and lower extremities with inflammatory synovitis. The presence of rheumatoid factor auto antibody is a major immunologic abnormality of rheumatoid arthritis. However, rheumatoid factor is not specific for rheumatoid arthritis, and these auto antibodies may be detected in normal individuals and in patients with a variety of conditions, including viral infections, liver disease and other auto-immune disorders. In [the worker s] case, the description of his condition appears to not favour this diagnostic possibility. Osteoarthritis Osteoarthritis is the consequence of cartilage loss of the joint that is the most common form of arthritis. It prevalence and severity parallel age in most individuals, and more than half of all persons over age 65 have X-ray changes of osteoarthritis affecting their knees. Other factors, in addition to age, are involved in OA. Occupations that subject particular to repetitive trauma predispose individuals to osteoarthritis of those joints. Prolonged overuse of any particular joint can be related to its development. Obesity is another factor that correlates well with OA of the knee. Other factors associated with OA include trauma, a history of inflammatory arthritis, and metabolic disorders such as gout. Cartilage damage by inflammation in rheumatoid arthritis, by urate, or CPPD is further altered by osteoarthritis. Once it starts, OA continues unchecked. With cartilage loss, its architecture changes and the mechanics of joint use

7 Page: 6 Decision No. 2464/03 are altered, leading to more stress and further joint damage. Thus, the process of OA becomes self perpetuating. The clinical diagnosis of OA is confirmed with X-rays of the affected joint. The classic radiographic findings of bony proliferation, called osteophytes, appear at the margins of the joint. With cartilage loss, joint space narrowing and bony sclerosis below the cartilages develops as the disease progresses. Later changes include the formation of cysts and bone remodeling with alteration of the shape of bone ends. Because the diagnosis is confirmed by history and physical examination, routine blood tests are normal unless there is some other associated condition such as CPPD, rheumatoid arthritis or gout. As in [the worker s] case, OA involves a typical pattern affecting distal finger joints as well as carpometacarpal joints, neck and lumbar spine, metatarsal joints of the feet, as well as knees and hips. When three or more joints are affected, this is termed generalized OA. The Most Likely Diagnosis The primary diagnosis in [the worker s] case is gouty arthritis. This diagnosis is based on the strong family history, recurrent episodes of podagra (painful gouty inflammation of the foot), and reports of elevated serum uric acid crystals from both of his knees (1994 and 1996), and his left toe (1994). The diagnosis of gout is also in keeping with his favourable response of these attacks to knee joint injections of cortisone and oral colchicines medication. Moreover, Dr. Porter s description at arthroscopy March 15, 1996 of, calcific deposits covering the articular surface of the left knee are more in keeping with uric acid crystals and a previous cortisone injection than the presence of calcium pyrophosphate crystals. The recent X-ray of the feet, taken May 5, 2004, also showed changes in keeping with gouty tophi of the 1 st metatarsophalangeal joints. In [the worker s] case, there are two secondary diagnoses. The first, recurrent posttraumatic left and right knee strain, aggravated by his underlying hyperuricemia and gouty arthritis. As such in this case, the link between trauma and gouty synovitis is that his gouty condition predisposed him to pain and inflammation from trauma rather than being fundamentally responsible for it. The second diagnosis is that of generalized osteoarthritis, confirmed in the May 6, 2004 report of X-rays of his hands and feet, and both knees. Here, the link between knee strain and gout may have advanced his heredity predisposition to osteoarthritis rather than being fundamentally

8 Page: 7 Decision No. 2464/03 responsible for it. However, the radiology report by Dr. Jaward, May 6, 2004, notes both knees show, minimal osteoarthritis and in particular, no description suggesting chondrocalcinosis or pseudogout. Although rheumatoid factor was reported positive once, November 25, 1996, there are no other clinical, radiologic or laboratory tests supporting a diagnosis of rheumatoid arthritis. Moreover, a positive rheumatoid factor test may be seen in many non-rheumatic conditions such as viral infections or non-specific fatty liver. 2 a. Based on the medical reports on file, is there any component of rheumatoid arthritis contributing to the worker s current impairment related to his knee condition? No. See my comment above. 2 b. Please comment on the role of gout or pseudogout, any impact these may have on his current knee condition. First, I have no evidence to support a diagnosis of pseudogout in [the worker s] case. Rather, I believe his basic diagnosis is gouty arthritis. Its relationship to his current left knee condition is described above in my response to Question Please comment on any relationship between the worker s knee condition and the accidents in February of 1979, October of 1982, December of 1983, and December of 1987, as described in the Panel s finding of fact. Is it medically likely that these accidents or their sequelae caused the worker s left knee condition, or permanently aggravated an underlying condition in the left knee? Please explain the reasons for your opinion. These accidents represent recurrent posttraumatic left knee strains aggravated or magnified by his underlying inflammatory gouty arthritis. As such, they may have advanced the presence of his minimal osteoarthritis of the left knee. This osteoarthritis affecting both knees is a permanent condition that can be expected to progress in coming years. Moreover, unless his serum uric acid is controlled by medication, his gouty arthritis can be expected to contribute to the advancement of his left knee osteoarthritis.

9 Page: 8 Decision No. 2464/03 4. Is there any other medical information which you feel would be of assistance in the Panel or Vice-Chair and Parties in understanding the nature and etiology of the worker s condition? No, but I would be pleased to answer any question the Panel might have about my views expressed above. [26] The Panel noted, subsequent to receiving the opinion of Dr. Gordon, that he had answered question 3 incorrectly in that he had not referred to worker s left knee accidents in July 1991, January 1995 and April 1995 as set out in the Panel s original question to him. The Panel returned the file to Dr. Gordon and asked him to reconsider his opinion in light of the totality of the worker s accidents in regard to his left knee. Dr. Gordon reviewed the file and advised the Panel that the addition of the three accidents, as noted above, did not result in a basic change to his previous medical opinion. (iv) The Panel s Analysis [27] The issue for the Panel to determine is whether a series of work related accidents significantly contributed to, or permanently aggravated, the worker s left knee difficulties described as minimal osteoarthritis by x-rays of May [28] The Panel, before reaching its ultimate findings in regard to this issue, determined that it would put significant weight on the medical opinion of Dr. Gordon based on his medical credentials and that he had the Panel s findings of fact (Decision No. 2464/03I) and the worker s medical history of gout and gouty attacks since Dr. Gordon also obtained, post-hearing, additional medical evidence, including the x-rays of 2004, that were not included in the worker s file. [29] The Panel, from the analysis of Dr. Gordon and other evidence in the file, finds the following as fact: [30] - The worker suffers from the condition of gouty arthritis and this condition is the primary medical diagnosis in regard to the worker s left knee condition. The worker suffers from polygout in that he has had gouty attacks in a number of joints of the body including both great toes (prior to the 1990 s), and subsequently, in the both knees and the left elbow. [31] - The worker also suffers from a hereditary predisposition to arthritis and generalized osteoarthritis. This finding is supported by the opinion of Dr. Gordon and x-rays of 2004 that show that the worker has osteoarthritis in his hands, feet and both knees. [32] - The worker s various left knee injuries did not cause the worker s gout. Gout is a metabolic condition that is closely related to heredity. This is consistent with the worker s testimony that various members of his family also suffer from gout. The worker s gouty attacks are often unrelated to trauma or accident. In July 1994 it was suspected that the worker s was developing recurrent crystalline synovitis in both knees.

10 Page: 9 Decision No. 2464/03 [33] - The worker s gouty condition of the joints (including the knee) can become manifest or be provoked by trauma (the medical opinion of Drs. Gordon, Roddy and Hignell). The worker s gouty attacks could also occur, from the testimony of the worker, spontaneously without any identifiable precipitating event. This is the worker s treatment history in regard to his left knee in late 1995 and In February 1996 the worker saw Dr. Porter with left knee problems unrelated to trauma. In April 1996 Dr. Porter opined that the worker was suffering from crystalline synovitis such as gout or degenerative arthritis in association with a degenerative medial meniscus tear. An arthroscopic examination did not reveal a meniscus tear. There was tremendous chondrocalcinosis within the articular surfaces which were covered with calcific deposits. The Panel accepts Dr. Gordon s analysis that these deposits were consistent with a diagnosis of gouty arthritis. This diagnosis is supported by the testimony of the worker who stated that Dr. Porter aspirated his left knee on several occasions in 1996 and he was informed that he had gouty arthritis of the left knee. [34] - Gouty arthritis is associated with osteoarthritis in that it can contribute to cartilage damage and the ultimate diagnosis of osteoarthritis. [35] - The development of osteoarthritis is associated with the aging process. [36] The Panel, after considering all of this evidence including its findings of fact as noted above, concludes that the worker s various left knee injuries were not significant contributing factors, individually or taken as a whole, in causing the worker s left knee problems (osteoarthritis) nor did the accidents hasten the development of the worker s osteoarthritis. [37] In reaching this conclusion, the Panel took particular notice of the following: [38] The worker s accidents were generally minor in nature and did not result in direct trauma to the worker s knee joint. The worker was able to return to his regular job duties after each accident. The Panel recognizes that injuries such as a strained ligament may result in stress on the knee joint. However, after every injury the worker received immediate and proper medical care in the form of medication, rest and physiotherapy. [39] There were lengthy periods of time, after the accidents in 1984 and 1991, when the worker was not treated for left knee difficulties. This indicated that the worker had recovered from these injuries. [40] The only work related accidents that were compensable in 1995 were minor in nature and paid on an aggravation basis. There were two flare-ups of the worker s gouty arthritis. The Panel accepts Dr. Cadman s opinion that these flare-ups resolved after a short period of time. The more serious gouty attacks of the knee occurred in late 1995 and These attacks came on with no precipitating event. The worker was treated by Drs. Zaitzeff, Porter and Roddy in Knee problems could come on while walking or sitting. A number of knee aspirations showed multiple monosodium urate crystals that the panel has concluded represented gouty attacks unrelated to work. This finding is supported by the medical opinions of Drs. Gordon and Hignell.

11 Page: 10 Decision No. 2464/03 [41] Dr. Gordon found that the worker s primary medical condition was gouty arthritis. The worker also has a diagnosis of generalized osteoarthritis or a hereditary disposition to arthritis. Neither of these conditions is compensable. Both of these conditions could contribute to the worker s osteoarthritic condition of the worker s left knee. [42] It was the collective opinion of the Board s physicians (Drs. Cadman, Hignell and Wentzell) that the worker s compensable injuries did not result in a permanent injury to the worker s left knee. Dr.Gordon would only offer the possibility (using the word may ) that the worker s injuries advanced the presence of the worker s minimal osteoarthritis. Dr. Gordon emphasized that the worker s arthritis was minimal by putting the word minimal in italics. [43] From the above paragraph, the Panel notes that the worker s osteoarthritis of the left knee, by x-rays in 2004, was minimal and not diagnosed as greater than the worker s general arthritis in his feet and hands. The Panel has also found that arthritis is associated with the aging process. The worker was 56 years old when the x-rays were taken in [44] The Panel ultimately concludes, based on the six paragraphs above, that it is more probable than not, that the worker would have minimal arthritis of the left knee based on his age, spontaneous gouty attacks and hereditary disposition to arthritis - regardless of the various left knee accidents he suffered from 1982 to The Panel finds that the worker s accidents did not cause or advance the presence of the arthritis in his left knee. [45] In reaching these conclusions the Panel considered the medical opinions of Dr. J. Porter, orthopaedic surgeon, and Dr. W. Fidler, rheumatologist. [46] On March 7, 1995 (referencing a letter of December 21, 1994) Dr. Porter stated that the worker s gouty arthropathy was a compensable problem. It is not clear whether Dr. Porter s letter refers to the worker s right or left knee. Dr. Porter had performed arthroscopic surgery on the worker s right knee in Regardless, Dr. Porter went on to state that the gout was related to all the worker s previous difficulties he had with his knee. Dr. Porter also stated that the worker had degenerative arthritis and given the fact that the knee flares up with trivial injuries the knee problem should be considered a compensable problem. [47] The Panel does not agree that the worker s gout condition is compensable in and of itself. As stated earlier, gout is a metabolic condition associated with heredity. It is a pre-condition of this worker that would become compensable if a flare-up occurred due to a traumatic event at work. This is what occurred in relation to the worker s two minor accidents in The Panel has concluded that the worker recovered from his gouty flare-ups in In 1996 the worker had serious and significant knee problems due to his non-compensable hereditary condition unrelated to trauma. The significance of the gouty pre-condition was confirmed by arthroscopic examination in From this medical history the Panel concludes that the worker s hereditary gout condition contributed to the worker s osteoarthritis. However, the condition is not compensable.

12 Page: 11 Decision No. 2464/03 [48] In regard to Dr. Fidler, the doctor produced a medical report on March 8, 1999 and stated that the worker s degenerative arthritis of the left knee was as a result of previous injury. He referenced the worker s accidents of October 1982 and August He also believed the worker had a left knee injury in May 1994 and arthroscopic surgery to that knee in These later assumptions are incorrect as the accident and surgery involved the right knee. Therefore, the Panel put little evidentiary weight on this opinion. Dr. Fidler produced a second report in November 1999 and again stated that he felt the worker s accidents of 1982 and 1991 caused the worker s osteoarthritis of the knee. [49] Dr. Fidler gave his second opinion based on assumptions that the worker had continuous left knee treatment since 1991 and that ultimately resulted in Dr. Porter performing an arthroscope in April This assumption is contrary to the worker s medical history that shows that there was a considerable time period after 1991 when the worker was receiving no treatment for his left knee. Further, the arthroscope performed in 1996 was not in response to a work-related trauma but due to a series of spontaneous gouty attacks. Therefore, the Panel did not put significant weight on the second opinion of Dr. Fidler. [50] The Panel concluded, for the reasons stated above, that it prefers the combined medical opinion of the Board doctors and Dr. Gordon. Therefore, the worker s appeal is denied.

13 Page: 12 Decision No. 2464/03 DISPOSITION [51] The worker s appeal is denied. [52] The worker is not entitled to a pension assessment for his left knee. DATED: November 28, 2006 SIGNED: T. Carroll, G.V. Stewart, D. Gillies