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 complaints were not related to his compensable injury of September 20, 2012. A hearing was held on December 4, 2013 to consider the matter.

Issue

Whether or not further responsibility for the worker's right knee complaints should be accepted as being related to the September 20, 2012 compensable injury.

Decision

That responsibility for the worker's right knee complaints should be accepted as being related to the September 20, 2012 compensable injury.

Decision: Unanimous

Background

On September 20, 2012, the worker twisted his right knee while pulling a skid with a pallet jack in the course of his workday. Initial medical reports diagnosed the worker with a right knee strain, but an MRI dated November 4, 2012 revealed a complex horizontal tear of the posterior horn on the body of the medial meniscus, as well as moderate chondromalacia.

Following consultation with a WCB medical advisor, the WCB advised the worker on November 27, 2012 that his claim for compensation had been accepted for a strain to the right knee occurring on September 20, 2012, but that his right knee strain had resolved and that his current difficulties were related to the pre-existing degenerative changes in his right knee.

On August 23, 2013, Review Office considered an appeal by the worker and determined current right knee difficulties were not related to the September 20, 2012 compensable injury. On September 3, 2013, the worker appealed Review Office's decision to the Appeal Commission and a hearing was arranged.

Reasons

The issue before us is whether responsibility for the worker’s right knee complaints should be accepted as being related to the compensable injury incurred on September 20, 2012.

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.

Worker’s Position

The worker advanced the position that when he twisted his knee pulling a skid on September 20, 2012, he not only incurred a strain to his right knee, but also caused a tear to his meniscus. He does not dispute the medical findings that at the time of this injury there were pre-existing degenerative changes in his right knee, but takes the position that new meniscal tearing occurred at that time and that the tear to the medial meniscus is the cause of his ongoing right knee complaints.

Employer's Position

The employer, represented by an advocate in the hearing, took the position that the medical evidence available does not support a finding that the worker’s right knee complaints are related to the compensable injury that occurred on September 20, 2012. She pointed to the WCB medical advisor’s opinion of November 28, 2012 to support the employer’s view that the only compensable injury was a knee strain, which had resolved by that date. There is, according to the employer, no evidence of a link between the diagnoses identified in the worker’s November 4, 2012 MRI results and the workplace accident of September 20, 2012. Although the complex horizontal meniscal tear could potentially be linked to the workplace injury, the employer argued that the medical evidence supports that the tear is the result of pre-existing, degenerative changes. In sum, the employer’s position is that the worker’s ongoing right knee complaints are the result of pre-existing, degenerative changes and not caused by the September 20, 2012 compensable workplace accident.

Analysis

In order to find that responsibility for the worker’s right knee complaints should be accepted as being related to the compensable accident of September 20, 2012, the panel must find on a balance of probabilities that the accident, or the accident in concert with the worker’s pre-existing condition, is the cause of the worker’s loss of earning capacity arising out of 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. The report of September 21, 2012, the day after the workplace accident, sets out that the worker noted localized pain to the right medial knee, pain to touch and increased pain with a change of position. The examining physician noted a diagnosis that indicates a question with regard to a right medial meniscal tear and a MCL minor sprain. An MRI was suggested if no improvement was seen in 3 weeks.

On October 19, 2012 the worker returned for a follow-up visit. Clinical findings noted were much the same as on the initial visit, and the worker was referred for an MRI.

The MRI report of November 4, 2012 indicates moderate chondromalacia, and also indicates that:

There is a complex but predominantly horizontal tear noted involving the posterior horn and body medial meniscus. This emerges along the inferior aspect and is associated with a small 12 mm parameniscal cyst. The lateral meniscus appears intact.

The worker’s medical file was reviewed by a WCB medical advisor, who noted in a November 20, 2012 report that:

The diagnosis related to the September 20, 2012 workplace incident is a right knee strain in an environment of likely pre-existing degenerative horizontal medial meniscal tear and moderate chondromalacia.

Sudden twisting of the knee joint on a planted foot could cause a strain.

Complex horizontal medial meniscal tears are usually degenerative. …the horizontal medial meniscal tear is…likely a pre-existing condition that was perturbed by the September 20, 2012 workplace incident.

The pre-existing conditions…do not appear to have significantly impacted this claimant’s recovery.

On November 28, 2012, the same WCB medical advisor gave the opinion that the worker has underlying pre-existing degenerative changes to his right knee, but that the effects of the right knee strain appear to have resolved.

The worker’s symptoms did not resolve and in February 2013, he went for an orthopaedic consultation. The February 22, 2013 report from that consult notes that:

There was tenderness along the medial joint line consistent with the MRI defined complex and horizontal tear involving the right medial meniscus.

…Some portion of the tearing is complex in nature and although the horizontal tearing may well be pre-existing, I would think the history and physical findings suggest that something did happen to his meniscus on that particular date.

While the WCB medical advisor on November 20, 2012 says the worker is “likely to continue to improve” and on November 28, 2012 says that “the effects of the right knee strain appear to have resolved,” the evidence before us does not support the medical advisor’s conclusion. In fact, the worker’s symptoms have not resolved. The worker, in his submission, noted that he continues to use a knee brace when he can in the activities of daily living, but that he is unable to use it in his work. From time to time, he experiences buckling, or giving way of his right knee. He also noted that he experiences ongoing impairment of function in his right knee.

The mechanism of injury as described by the worker was a torqueing type of injury: his right foot was firmly planted forward when his right knee twisted as he pulled a heavy pallet. As suggested by the orthopaedic consultant’s report, this mechanism of injury is consistent with the evidence of a meniscal tear.

The early medical reports, together with the evidence of the mechanism of injury, lend support to the worker’s position that the complex, horizontal medial meniscal tear is related to the September 20, 2012 injury.

The employer recognized, in her submission, that the meniscal tear is the only potential diagnosis arising from the MRI scan that could be linked to the workplace incident, but argued that the medical evidence suggests it is the result only of a pre-existing injury.

Our review of the medical reports on file leads us to a different conclusion. The WCB medical advisor noted in her November 20, 2012 report that the medial meniscal tear is “…likely a pre-existing condition perturbed by…” (emphasis added) the workplace accident. This is consistent with the opinion of the orthopaedic consultant that while the horizontal tearing may be pre-existing, something did happen to the worker’s meniscus on September 20, 2012.

Taking into account the mechanism of injury and the worker’s ongoing and unresolved symptoms as well as the initial medical reports that suggest a possible diagnosis of a meniscal tear and the later reports that suggest the workplace incident perturbed a pre-existing meniscal tear, we find, on a balance of probabilities, that the compensable injury was due in part to a compensable and non-compensable pre-existing medical condition. In accordance with the policy the panel finds that responsibility for the worker’s right knee complaints should be accepted as being related to the compensable injury incurred on September 20, 2012.

Panel Members

K. Dyck, Presiding Officer
A. Finkel, Commissioner
P. Walker, Commissioner

Recording Secretary, B. Kosc

K. Dyck - Presiding Officer

Signed at Winnipeg this 14th day of January, 2014