The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker is appealing the decision made by the Workers Compensation Board ("WCB") that his right knee meniscal tear was not the result of his October 17, 2012 compensable accident. A hearing was held on December 17, 2014 to consider the matter.

Issue

Whether or not the worker's ongoing right knee difficulties are related to the October 17, 2012 compensable injury.

Decision

That the worker's ongoing right knee difficulties are related to the October 17, 2012 compensable injury.

Decision: Unanimous

Background

In June 2013, the worker filed a claim with the WCB for a right knee injury that occurred on October 17, 2012 when he was performing a safety check on his truck. The worker advised that he crawled up onto the wheel and bumper to check the coolant and somehow he slipped off the truck and fell to the ground, twisting his knee in the process. The worker indicated that there were no witnesses but he reported the injury immediately. He said the pain in his knee slightly subsided so he continued to work but eventually his knee got worse and he attended a doctor the same day.

On July 10, 2013, the accident employer confirmed that the worker reported the October 2012 injury when it occurred. He said the worker told him that his doctor diagnosed him with a sprain injury to his knee and that he should take a couple of days off work. He said the worker worked on October 31, November 1, 2 and 5 and his last day was on November 20. The employer indicated that he had no recollection of the worker complaining of his knee during this time period and he did not notice the worker limping. In early spring, the worker told him that he might require surgery to his knee.

A Doctor First Report provided indicates that the worker attended a physician on October 17, 2012 and reported that he slipped while checking over a truck. The diagnosis was a knee sprain and the worker was advised not to work until October 22, 2012. An x-ray was ordered.

On October 20, 2012, the worker sought treatment from a chiropractor. The Chiropractor First Report with respect to that visit indicates the worker had decreased range of motion in his right knee, was unable to perform a deep knee bend and had a positive right MCL stress test. The chiropractor diagnosed the worker with an MCL sprain and queried whether there was a meniscal injury.

In a doctor's progress report for an examination on January 31, 2013, it was reported that the worker required an MRI of his right knee for the purposes of an employment application. The physician noted that the worker injured his right knee last year and that he could not fully flex his right knee on squatting.

An MRI of the right knee was done on February 24, 2013 and was compared to previous x-rays dated October 17, 2012. The MRI revealed:

1.  Horizontal tear posterior horn medial meniscus.
2.  Horizontal tear body lateral meniscus.
3.  Chondromalacia most pronounced at the lower trochlea.

In a March 28, 2013 report, an orthopedic surgeon noted that the MRI scan showed a medial meniscal tear with a minor degree of osteoarthritis and that x-rays showed minimal, if any, osteoarthritis. A knee arthroscopy and intra-articular surgery was recommended.

On June 12, 2013, the worker underwent right knee surgery and the post operative diagnosis was "Right knee medial meniscal tear, lateral meniscal tear and chondromalacia patellofemoral joint right knee. Chondromalacia was grade II, trochlear groove, patellofemoral groove 2 x 2 cm grade II."

On September 30, 2013, the WCB advised the worker that his claim was accepted for a right knee sprain occurring on October 17, 2012 but responsibility was not being accepted for the meniscal tear and subsequent surgery, as the evidence did not establish a continuity between the incident on October 17, 2012 and the February 2013 diagnosis of a meniscal tear.

A November 5, 2013 report from the treating surgeon set out that:

"Patient is seen concerning his knee. He had a traumatic injury falling off and twisting his knee on a truck. He had no previous knee pain prior to this. The injury and the diagnosis was definitely traumatic. He had meniscal tear with a little bit of osteoarthritis. This is obviously from the injury, and not from anything else."

On March 12, 2014, the worker was advised that the new information had been reviewed and that no change would be made to the WCB decision of September 30, 2013.

On May 27, 2014, the Worker Advisor Office submitted to Review Office that the medical information on the worker's file supported that meniscal damage was suspected three days following the injury and the mechanics of injury would support a diagnosis of a meniscal tear. It was further noted that the worker did not have any right knee difficulty prior to the October 17, 2012 incident and had enjoyed good recovery from the surgical repair.

Review Office referred the claim file to the WCB's healthcare branch to obtain a medical opinion regarding the etiology of horizontal tears and an opinion on the February 24, 2013 MRI findings and the surgical findings of June 12, 2013. The WCB orthopedic consultant, in an opinion dated July 30, 2014, concludes that the MRI and arthroscopic findings are better explained by degeneration rather than trauma.

On August 12, 2014, Review Office determined that the worker's ongoing right knee difficulties were not related to the October 17, 2012 workplace accident.

On September 5, 2014, the worker appealed Review Office's decision to the Appeal Commission and an oral hearing was arranged.

Reasons

The issue to determine is whether or not the worker's ongoing right knee difficulties are related to the October 17, 2012 compensable injury.

Applicable Legislation and Policy

In considering this appeal, the panel is bound by The Workers Compensation Act (the “Act”), regulations and policies of the Board of Directors.

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.

Workers Compensation Board Policy 44.10.20.10, Pre-Existing Conditions, (the “Policy”) provides that when a worker’s loss of earning capacity is caused in part by a compensable accident and in part by a non-compensable pre-existing condition or the relationship between them, the Workers Compensation Board will accept responsibility for the full injurious result of the accident. The policy goes on to provide that when a worker has:

1) recovered from the workplace accident to the point that it is no longer contributing, to a material degree, to a loss of earning capacity, and

2) the pre-existing condition has not been enhanced as a result of compensable injury arising out of and in the course of the employment, and

3) the pre-existing condition is not a compensable condition, the loss of earning capacity is not the responsibility of the WCB and benefits will not be paid.

Worker’s Position

The worker advanced the position that when he fell from the truck on October 17, 2012, he twisted his knee causing the tearing in the meniscus of his right knee. He immediately felt a pain in the knee and although it was initially diagnosed as a sprain, the symptoms did not resolve and later testing revealed the meniscal tear. The worker suggested the original diagnosis of a sprain was in error. The worker noted that prior to the accident on October 17, 2012 he had no knee difficulties. He took the position that his meniscal tearing occurred at that time and that the tears to the medial and lateral meniscus are the cause of his ongoing right knee complaints.

Employer's Position

The employer took no position.

Analysis

At issue is whether responsibility for the worker’s right knee complaints should be accepted as being related to the compensable accident of October 17, 2012. To find in favour of the worker, the panel must find on a balance of probabilities that the accident, or the accident in concert with a pre-existing condition, is the cause of the worker’s loss of earning capacity arising from his ongoing right knee complaints. The panel was able to make this finding.

In considering this appeal, we have reviewed the medical reports on file and considered the submissions of the worker with respect to his injury.

The worker saw a primary care physician on the date of the accident, within a few hours of his fall. The Doctor First Report, indicates on examination there was minimal swelling, full range of motion and no ligament laxity. The initial diagnosis, which the WCB accepted as a compensable injury, was a knee sprain.

Three days later, the worker attended a chiropractor as the pain in his right knee persisted. The Chiropractor First Report indicates that the worker was experiencing pain at the right medial aspect, described as 8/10. The worker was unable to perform a deep knee bend and had a positive right MCL stress test. His range of motion in the right knee was decreased and as a result his right meniscus could not be tested. The chiropractor noted a diagnosis of MCL sprain and queried whether there was a meniscal injury.

The worker attended for seven chiropractic treatments over the course of the following month, but noted in his submission that he didn’t see any improvement or change in his right knee as a result. He described being constantly aware of his knee between November 2012 and January 2013, noting particular difficulty and a feeling of weakness, or that the knee could give in, when walking down stairs.

In January 2013, as a result of his performance during a pre-employment screening test, the worker was advised to seek further medical attention with respect to a possible meniscal tear.

The subsequent MRI report dated February 25, 2013 noted the worker had horizontal tears to both the posterior horn medial meniscus and lateral meniscus in his right knee, as well as grade III chondromalacia in the lower trochlea and grade II chondromalacia involving the patella.

On March 28, 2013 the worker consulted with an orthopedic surgeon who noted that the “MRI scan shows medial meniscal tear with a minor degree of osteoarthritis.” At that time the worker was booked for surgery, which took place on June 12, 2013. The post-surgical diagnosis was right knee medial meniscal tear and chondromalacia patellofemoral joint right knee. The medial meniscus had a horizontal cleavage tear and the lateral meniscus had fraying.

The orthopedic surgeon, on November 7, 2013, provided an opinion that the “…injury and the diagnosis was definitely traumatic. He had meniscal tear with a little bit of osteoarthritis. This is obviously from the injury, and not from anything else.”

This opinion from the treating surgeon is challenged by the opinion of the WCB medical advisor who reviewed the file in July 2014 at the request of Review Office. The WCB medical advisor disagreed with the opinion of the surgeon stating the MRI and arthroscopic surgical findings are better explained by degeneration than by trauma. The medical advisor noted that fraying and horizontal or cleavage tears of the meniscus “…are generally considered to be of degenerative rather than traumatic etiology.”

In reviewing the evidence, the panel finds that the mechanism of injury as described by the worker is consistent with the evidence of a meniscal tear. A fall from the wheel of a truck to the ground below and resultant twisting of the right knee could have caused a traumatic injury to the worker’s meniscus. This is consistent with the conclusion of the treating orthopedic surgeon.

While the first physician’s report indicates only a sprain-type injury, we note that this assessment occurred within hours of the injury. The symptoms of a meniscal injury may not develop immediately and we have therefore placed less weight on this early diagnosis.

In fact, several days later, as noted in the first chiropractic report, different symptoms have presented, suggesting “internal derangement” and a possible diagnosis of a meniscal tear in the right knee. This report lends support to the worker’s position that meniscal tear is related to October 17, 2012 injury.

The evidence is that the worker had no symptoms prior to the injury, but we note that the evidence does not rule out a pre-existing condition that may have been asymptomatic until the injury of October 17, 2012. In this regard, we note the conclusion of the WCB medical advisor that the worker had a pre-existing degenerative injury to his right knee.

The evidence also points to a permanent change in course with respect to the pre-existing condition of the worker’s knee after the accident of October 17, 2012. The injury to the worker’s knee on that day permanently and adversely affected the pre-existing condition of his knee.

Taking into account the mechanism of injury, the early chiropractic findings suggesting a meniscal tear and the permanent changes in the worker’s right knee after October 17, 2012, we find on a balance of probabilities that as a result of the accident, there was a permanent enhancement of the pre-existing condition in the worker’s knee causing the worker’s loss of earning capacity.

We have therefore concluded that the worker's ongoing right knee difficulties are related to the October 17, 2012 compensable injury.