The Appeal CommissionThe Workers Compensation Act of Manitoba

Applicable Legislation and Policy

There are two issues before the panel arising from the worker's 2006 compensable injury.

In deciding the appeal, the Appeal Commission panel is bound by the Act. Under subsection 4(1) of the Act, where a worker suffers personal injury by accident arising out of and in the course of employment, compensation shall be paid to the worker by the WCB. Subsection 39(2) of the Act provides that the WCB will pay wage loss benefits until such a time as the worker’s loss of earning capacity resulting from the accident ends.

WCB Policy 44.10.80.40, Further Injuries Subsequent to a Compensable Injury (the “Further Injuries Policy”) applies to circumstances where a worker suffers a separate injury which is not a recurrence of the original compensable injury, but where there may be a causal relationship between the further injury and the original compensable injury. WCB Policy 44.10.20.10, Pre-existing Conditions, deals with the relationship between a worker's compensable injury and a pre-existing condition.

Worker's Position

The worker was represented by a worker advisor who made a submission on the worker's behalf. The worker answered questions posed by his representative and the panel.

Issue 1: Whether responsibility should be accepted for the worker's left knee complaints as having a relationship to the right knee injury of June 23, 2006.

The worker advisor submitted that the degeneration of the left knee progressed at an accelerated rate as a result of the worker's compensable injury. He said the evidence on file shows that the worker had prior left knee issues which had been asymptomatic for a number of years between a surgery in 2000 and 2006 when he was injured at work. Following his work injury the worker developed an altered gait. He worked for a number of months, both regular duties and modified duties relying more and more on this left knee because of the status of his compensable right knee injury.

The worker advisor submitted that the worker had a sense of instability and there were actually instances of falls due to his compensable injury. He said this likely contributed to the potential for further damage to both the left and right knees. He also said there were recovery periods from a number of compensable surgeries where use of his right knee was very restricted, resulting in the increased reliance on his left knee.

He noted that the deterioration of the left knee was rapid and that this was causally related to his compensable injury. He said this position has been supported in general terms by the worker's orthopedic surgeon, the Board’s orthopaedic consultant, a sports medicine physician, and an occupational health physician.

Issue 2: Whether the worker is entitled to wage loss benefits beyond October 10, 2008.

The worker advisor referred to new evidence that the worker has a posterior horn medial meniscus tear. He said the information on file dating back to 2006 supports such a tear. He noted there was confusion stemming from the reports provided by the first orthopaedic surgeon, but that the recent medical information confirms the actual status of the worker's right knee.

The worker advisor stated that the worker had compensable surgery on September 25, 2007 debriding a medial meniscal tear and an MRI in 2008 showed that same meniscal tear was there. He noted that the new evidence shows there was still a medial meniscal tear of the posterior horn in 2011.

He submitted that this tear was either caused by:

1. the initial compensable injury,

2. a recurrence of the compensable injury by way of further fraying that happened despite treatment, or a

3. a further injury that happened as a consequence of treatment.

He referenced the Further Injuries which describes when a further injury is going to be compensable. He said that the worker's right knee continued to deteriorate because of the repeated debridement of cartilage in his knee which was authorized and paid for by the WCB. He submitted that the claim continues to be compensable because the cause of the further injury arises out of a situation over which the WCB exercised direct specific control and out of delivery of treatment for the original compensable injury.

The worker advisor also said that the three WCB-authorized surgeries caused enhancement of the pre-existing degenerative conditions in the worker's right knee. The worker advisor submitted that the debridement of chondromalacia has accelerated the deterioration of the right knee. His position was that as the WCB authorized the surgery, the acceleration in deterioration is the WCB's responsibility under WCB Policy 44.10.20.10, Pre-existing Conditions. In answer to questions the worker described his duties, the injury, onset of symptoms, activities after the injury and medical treatments.

The worker asked that the panel take a compassionate and humanistic point of view in deciding the appeal.

Employer's Position

The employer was represented by an advocate who participated by teleconference.

Issue 1: Whether responsibility should be accepted for the worker's left knee complaints as having a relationship to the right knee injury of June 23, 2006.

Regarding the worker's left knee, the representative referred to a January 18, 2010 report from a WCB medical advisor. The medical advisor noted that the worker had a left knee arthrosis in 1992 and commented that over a period of eighteen years, arthrosis usually progresses, especially if the individual keeps running, and that a knee joint replacement is a reasonable treatment for progressive knee joint arthrosis.

The representative submitted that the medical advisor did not find a relationship between the left knee replacement and the right knee injury. The representative noted that the worker began complaining about the left knee within one or two months of the right knee injury which suggests the left knee injury is not related to the right knee injury.

Issue 2: Whether the worker is entitled to wage loss benefits beyond October 10, 2008.

Regarding the worker's right knee, the representative again referred to the WCB medical advisor's opinion. He noted that the medical advisor opined, after reviewing the file, that “A medial meniscus tear does not have a probable cause/effect relationship with the events in question.”

Regarding the new evidence, the representative questioned whether it is possible to relate this five year post-accident diagnosis with the accident that took place in May 31, 2006. He also noted the opinion from WCB medical advisor stating that even if the panel was to accept that diagnosis of medial meniscus tear, it doesn’t have any causal relationship to the accident that occurred in May 31, 2006.

Analysis

There are two issues before the panel.

Issue 1: Whether or not responsibility should be accepted for the worker's left knee complaints as having a relationship to the right knee injury of June 23, 2006.

For the worker's appeal of this issue to be successful, the panel must find that his left knee condition qualifies as a further injury under the Further Injuries Policy. There are three tests set out in this policy. The worker advisor submitted that the left knee injury is acceptable under paragraph (i) of the policy which provides that a further injury occurring subsequent to a compensable injury is compensable where the further injury is predominantly attributable to the compensable injury.

The panel finds, on a balance of probabilities, that the left knee injury is not related to the right knee injury and that responsibility should not be accepted for the worker's left knee complaints. At the hearing the worker's representative submitted that the likely cause of the left knee problem was the worker continuing to work four months in a physical job, going back to work, and the various surgeries the worker underwent.

In the panel's opinion, the evidence does not establish that the right knee injury significantly contributed to the enhancement of the left knee osteoarthritis and the resulting total knee replacement. The panel finds that the extent that the worker used his left knee after the accident was limited:

• within one to two months of the workplace injury the worker began experiencing pain in his left knee. The worker continued working for approximately four months after the accident. Although performing his regular duties after the accident, the worker indicated that he ceased doing the heavy physical work and obtained assistance from others. By September, he was doing little physical work. It is also noted that his duties involved driving a large truck long distances and finds that much of the time the left knee would not be used.

• the worker stopped working on October 4, 2006. At the first hearing, the worker indicated that he spent about 1 hour per day on his feet after he stopped working. He confirmed this estimate at the second hearing. The panel finds that this reduced mobility and reduced use of the left knee reduced the time during which the left knee would be load bearing and stressed.

The panel agrees with the assessment of the WCB medical advisor dated January 22, 2010. The medical consultant noted that the worker was documented as having a left knee arthrosis in 1992, probably related to multiple injuries. He opined that over a period of 18 years, arthrosis usually progresses and that left knee joint replacement is a reasonable treatment for progressive knee joint arthrosis. He concluded that there is insufficient information to establish that the worker had a greater reliance on the left knee in the examination notes on file.

The panel also notes that the WCB orthopaedic consultant commented in a memo dated June 19, 2008 that "problems with the left knee are documented prior to the CI of the right knee. There is no medical evidence of aggravation of the left knee because of problems with the right knee. Increased weight bearing on the left knee for a period of time would not by itself be expected to cause deterioration of the meniscal lesions."

The panel finds, on a balance of probabilities, that the worker's need for a left knee replacement was not related to the worker's right knee injury. The worker's appeal regarding his left knee injury is dismissed.

Issue 2: Whether or not the worker is entitled to wage loss benefits beyond October 10, 2008.

For the worker's appeal of this issue to successful, the panel must find that the worker's compensable injury caused the worker to sustain a loss of earning capacity.

The panel notes that this claim has been complicated by confusion regarding the medical procedures that were performed on the worker's right knee and conflicting medical opinions and diagnostic tests. Evidence on the file includes:

• no tear of the right medial meniscus found: initial evidence indicates no tear of the right medial meniscus. This includes the August 2006 MRI and an arthroscopy performed on the right knee on December 6, 2006.
• tear of right medial meniscus noted: a June 2007 MRI reports a complex tear of the posterior medial meniscus.
• previous tear of right meniscus noted: a second arthroscopy was performed by the first orthopaedic surgeon on the right knee on September 25, 2007 which noted "a previous partial meniscectomy and another flap based proximally and some cleavage tear of the medial meniscus."
• tear of right medial meniscus noted: a March 2008 MRI reports that the tear of the posterior horn of the medial meniscus is seen unchanged from the previous examination of 2007.
• no tear of right meniscus found: in May 2008 a second orthopaedic surgeon performed an arthroscopy and found no tear of the right meniscus.
• prior surgery to right meniscus noted: a March 2011 MRI found that "the medial meniscus is small in the posterior horn adjacent to the root and likely this relates to prior surgery." No retear of the meniscus was found.
• small tear of right meniscus found: an August 2011 arthroscopy performed by a third orthopaedic surgeon confirmed the existence of a small tear involving the posterior portion of the posterior horn of the medial meniscus. In a report dated June 1, 2012, the orthopedic surgeon wrote that "The meniscus tear itself was actually quite small and I really could not tell whether in fact this was acute or chronic."

The panel has considered all the evidence and is not able to find, on a balance of probabilities, that the worker tore his right medial meniscus in the 2006 workplace accident. The panel notes there is conflicting evidence on the existence of the meniscal tear in 2006, but finds the evidence that the medial meniscus was intact in 2006 to be more substantial. This evidence includes the August 2006 MRI, the December 2006 arthroscopy and the May 23, 2008 arthroscopy which found that the medial meniscus was intact. The panel places considerable weight on the 2008 arthroscopic evidence as this involved a visual inspection by a specialist.

While a meniscus tear was clearly identified in 2011, the panel is not able to relate this finding back to 2006 or to 2008. The panel notes that the orthopedic surgeon who performed the arthroscopy on the worker's right knee in August 2011 was specifically asked whether the tear was acute in nature or degenerative and whether the findings arise from the worker's previous surgeries or are coincidental or separate findings. He responded that he could not determine whether the tear was acute or chronic.

The panel notes, however; that the tear noted in the 2011 arthroscopy has no apparent impact on the function of the knee given the orthopedic surgeon's comment that he placed no restrictions on the knee. In the panel's view, the absence of functional limitation in 2011 from the meniscal tear strongly suggests that the meniscal tear was not a factor and likely not present in 2006 or 2008. The panel concludes that the worker's difficulties with his right knee are not due to an acute workplace injury.

The worker advisor also submitted that the three WCB-authorized arthroscopic surgeries resulted in a further injury in accordance with the Further Injuries Policy. The worker advisor also submitted that the worker's right knee injury was enhanced in accordance with WCB Policy 44.10.20.10, Pre-existing Conditions.

The panel finds, on a balance of probabilities, that the worker did not sustain a further injury as provided by the Further Injuries Policy and that the worker's knee condition was not enhanced as provided by the Pre-existing Conditions Policy. In reaching this decision the panel agrees with the opinion of the WCB medical advisor dated January 18, 2010. The medical advisor commented that:

"Grade III patellofemoral chondromalacia was documented in the first arthroscopy as well as the third, with no documented anatomic progression. It does not appear evident how the arthroscopies themselves, which were authorized by the WCB, would make the patellofemoral pain worse, on the balance of probability. Therefore, I would state that the surgical procedures have not probably enhanced the worker's pre-existing right knee chondromalacia of the patellofemoral joint."

The panel also accepts the findings of the August 31, 2011 arthroscopy. The operative report concludes that "This knee is surprisingly well preserved and certainly should not require any surgical intervention for a long time." In a report dated June 1, 2012, the orthopedic surgeon reported that:

"… I found a small tear involving the posterior portion of the posterior horn of the medical meniscus with a little bit of very mild synovitis and some quite mild chondromalacia in the medial femoral condyle grade 2 from about 30-40 degrees of knee flexion and some very mild changes underneath the patella and femoral groove. The degenerative changes were extremely mild and certainly do not indicate a knee that required further intervention at that time, particularly in form of major surgery like joint replacement." (underlining added)

The panel finds that the opinion noted above does not support a finding that the worker has suffered a further injury or an enhancement of his pre-existing degenerative condition.