Decision #32/12 - Type: Workers Compensation

Preamble

The worker is appealing the decision made by Review Office of the Workers Compensation Board ("WCB") which determined that there was no relationship between the current diagnosis of a lateral meniscus tear and the compensable injury of May 5, 2010. A hearing was held on January 12, 2012 to consider the matter.

Issue

Whether or not the worker is entitled to wage loss benefits beyond July 27, 2010 in addition to benefits issued for the period October 13, 2010 and October 18, 2010.

Decision

That the worker is not entitled to wage loss benefits beyond July 27, 2010 in addition to benefits issued for the period October 13, 2010 and October 18, 2010.

Decision: Unanimous

Background

The worker reported that she injured her left knee on May 5, 2010 in a work-related accident when she bent down to pick up an object. She said she "slightly twisted" and it felt like someone stabbed her in the back of the left knee. The worker reported that she continued working but within 10 minutes her left knee was just too sore to stand on.

Initial medical reports revealed that the worker attended a hospital emergency facility for treatment on the day of accident and was diagnosed with a left knee strain. The worker also attended a chiropractor on May 12, 2010 and the diagnosis was "possible internal cartilaginous derangement and quadriceps strain." When seen by her family physician on May 13, 2010, a meniscus tear was questioned and an MRI assessment was ordered. On June 3, 2010, the MRI revealed the following:

  1. Partial discoid lateral meniscus.
  2. No evidence for a medial meniscal tear.

The worker attended a physiotherapist for treatment on June 25, 2010. The worker complained of pain with decreased range of motion with mechanical blockage and intermittent swelling. The therapist's diagnosis was a possible meniscus tear.

On July 16, 2010, the family physician noted that there was no change in the worker's condition and that a referral to an orthopaedic surgeon was pending.

On July 26, 2010, a WCB medical advisor reviewed the medical reports at the request of primary adjudication. In his opinion, the worker suffered a left knee strain/sprain related to the accident. He noted that although the chiropractor questioned internal cartilaginous derangement within the left knee, the June 3, 2010 MRI demonstrated no such derangement medially. He said knee sprains/strains resolve within four to six weeks. The medical advisor noted that the MRI found no evidence of a meniscus tear and that there was no pathology thus far that would require a surgeon's input.

The medical advisor also stated that there was no evidence of a pre-existing condition delaying the worker's recovery. Although the MRI identified a partial discoid lateral meniscus, this was considered an anatomic variant, occurring in 1.5% to 3% of the normal population. He noted that there was no evidence of lateral knee symptomatology and no evidence of a tear of the lateral or medial meniscus and therefore the partial discoid lateral meniscus was not likely clinically significant.

On July 27, 2010, the WCB determined the worker was capable of working regular hours and duties effective July 27, 2010. The case manager noted in the decision that given the medical information on file (normal left knee MRI, the lack of effusion, the normal examination reported by the family physician in his June 22, 2010 progress report), there did not appear to be any patho-anatomic basis on which to restrict work hours or duties.

On July 30, 2010, the worker advised the WCB that she was unable to do her regular duties as she couldn't walk. She said her physiotherapist told her that her knee was off track.

In a report dated September 2, 2010, an orthopaedic surgeon reported that he saw the worker on August 30, 2010 regarding her left knee difficulties. He stated: "History and injury pattern and ongoing symptoms relate probably to extensor mechanism problems relative to the patellofemoral joint and the discoid lateral meniscus may have been torn or this may just be an incidental finding. It is probably reasonable to wait this out a little longer with conservative treatment, but if she has not responded, I believe she would be prepared to undergo a scope, which would include looking at the above differential and possible patellar release if indicated."

A WCB call-in examination took place on October 13, 2010. The medical advisor outlined the opinion that the proposed surgery and the prescribed buttress brace did not appear to be appropriate in relation to the compensable injury. The medical advisor stated in part:

…Even if a lateral meniscal tear were eventually to be found, such a tear would not be due to the compensable injury as findings in the early file are consistently related to the medial joint line -- not the lateral joint line as would be expected had a lateral meniscus tear been incurred with the compensable injury.

On November 10, 2010, a WCB orthopaedic consultant wrote to the treating orthopaedic surgeon to advise that based on the history and examination findings, the WCB was unable to accept responsibility for the proposed arthroscopic surgery.

On November 10, 2010, a decision was issued to the worker that the WCB was unable to support time loss benefits beyond July 27, 2010 or accept responsibility for the ongoing medical treatment and surgery as it was felt that her current symptoms were not related to the May 5, 2010 compensable injury.

The worker underwent surgery to her left knee on January 12, 2011. The postoperative diagnosis was: "Synovitis, femoral chondromalacia, patellar maltracking and stability, lateral meniscal tear and discoid meniscus left knee."

On March 17, 2011, a WCB orthopaedic consultant reviewed the arthroscopy findings and stated, in part:

  • the arthroscopy findings revealed a tear of the lateral meniscus which was not evident on prior MRI. Also found were patella maltracking, chondromalacia, and a plica which are findings unrelated to trauma. The medial meniscus was intact, but there was degenerative chondromalacia of the medial compartment.
  • the clinical findings shortly after the workplace injury were not consistent with trauma to the lateral compartment of the knee; rather, medial joint line tenderness was noted.
  • discoid lateral menisci are particularly prone to tearing with activities of daily living, often without accompanying symptoms. Symptomatic lateral meniscal tear would be expected to be associated with a clinical finding of tenderness of the lateral joint line.
  • the surgery of January 12, 2011 was not related to the workplace injury which caused a soft tissue strain of the left knee.

Based on the medical opinion provided by the WCB orthopaedic consultant, the worker was advised on March 17, 2011 that no change would be made to the previous decision of November 10, 2010.

On May 16, 2011, a worker advisor provided the WCB with a report from the treating orthopaedic surgeon dated May 10, 2011 to support that the worker was entitled to coverage of benefits and services beyond July 27, 2010. The worker advisor stated: "It is our opinion that [the orthopaedic surgeon] has provided clinical evidence of a meniscal tear during arthroscopy which he relates to the mechanism of injury. [The orthopaedic surgeon] also provided evidence of other possible pain generators that could have resulted from the injury."

On May 24, 2011, the WCB case manager confirmed the previous WCB decision that the lateral meniscal tear was not the result of the workplace injury and that the surgery of January 12, 2011 along with associated medical treatment, medical restrictions and time loss were not the WCB's responsibility. On June 17, 2011, the worker advisor appealed the decision to Review Office.

On August 16, 2011, Review Office confirmed that there was no entitlement to wage loss benefits beyond July 27, 2010 other than the wage loss benefits that were issued for October 13, 2010 and October 18, 2010 (the dates of WCB medical examinations). Review Office noted that the findings following the workplace injury consistently relate to the medial joint line and not the lateral joint line. It accepted the opinion of the WCB orthopaedic consultant outlined on March 17, 2011. Review Office concluded that the evidence on file including the initial diagnosis and the lack of findings related to the lateral joint line following the workplace injury did not support a causal relationship between the diagnosis of a lateral meniscus tear and the compensable injury of May 5, 2010. On October 11, 2011, the worker advisor appealed Review Office's decision to the Appeal Commission and a hearing was arranged.

Reasons

Applicable Legislation:

The worker is employed by a federal government agency or department and her claim is therefore adjudicated under the Government Employees Compensation Act (“GECA”). Under the GECA, an employee who suffers a personal injury by an accident arising out of and in the course of employment is entitled to compensation. The GECA defines accident as including “a willful and an intentional act, not being the act of the employee, and a fortuitous event occasioned by a physical or natural cause.”

Pursuant to subsection 4(2)(a) of the GECA, a federal government employee in Manitoba is to receive compensation at the same rate and under the same conditions as a worker covered under The Workers Compensation Act (the “Act”). The Appeal Commission and its panels are bound by the Act, regulations and policies of the Board of Directors.

Subsection 39(1) of the Act provides that wage loss benefits will be paid: “…where an injury to a worker results in a loss of earning capacity…” 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 ends, or the worker attains the age of 65 years.

Worker's position:

The worker appeared at the hearing accompanied by a worker advisor. The worker's position was that she sustained an injury to her left knee during the course of her employment on May 5, 2010 and that the injury resulted in the surgical treatment of January 12, 2011. The worker relied on the May 10, 2011 report of the treating orthopaedic surgeon to support her position. It was submitted that the orthopaedic surgeon provided evidence of how the January 12, 2011 findings related to the May 5, 2010 injury. This information was in accordance with WCB Policy 44.10.20.10 regarding pre-existing conditions. It was also noted that the worker had no history of left knee symptoms prior to the workplace injury and was able to perform her full regular duties. Overall, it was submitted that the evidence supported a relationship between the arthroscopic findings and the May 5, 2010 compensable injury and therefore the WCB should accept responsibility beyond July 27, 2010.

Employer's position:

A representative from the employer appeared at the hearing. The employer agreed with the WCB's previous decision and supported the WCB orthopaedic advisor's opinion dated March 17, 2011 where he opined that the clinical findings shortly after the workplace injury were not consistent with trauma to the lateral compartment of the knee. Rather, medial joint line tenderness was noted. The later arthroscopic findings revealed a tear of the lateral meniscus and indicated that the medial meniscus was intact. The workplace injury was not consistent with trauma to the lateral compartment of the knee and, based on the mechanism of injury, it was submitted that the worker's pre-existing condition was neither aggravated nor enhanced. The employer suggested that the worker's surgery was the result of non-occupational reasons rather than her work related injury, and asked the panel to uphold the WCB decision which denied benefits beyond July 2010.

Analysis:

The issue before the panel is whether or not the worker is entitled to wage loss benefits beyond July 27, 2010 in addition to benefits issued for the dates October 13, 2010 and October 18, 2010. In order for the worker's appeal to succeed, the panel must find that the injury to the worker's left knee on May 5, 2010 was more serious than a soft tissue strain and that the compensable injury/diagnosis either caused or contributed to the need for arthroscopic surgery on January 12, 2011. On a balance of probabilities, we are not able to make that finding.

The worker’s claim was originally accepted by the WCB based on a diagnosis of a left knee strain. The emergency department report, the doctor's first report and chiropractor's first report all reference medial side symptoms and a medial meniscus tear was suspected. It was subsequently determined by MRI imaging and arthroscopic surgery that there was no damage or tear to the medial side structures.

The worker, however, continued to complain of pain in her knee, and was referred to an orthopaedic surgeon. Arthroscopy performed January 12, 2011 indicated the following post-operative diagnoses: synovitis, femoral chondromalacia, patellar maltracking and instability, lateral meniscal tear and discoid meniscus left knee.

The question the panel must ask is whether there is evidence to satisfy us on a balance of probabilities that any of these conditions were caused by the compensable injury.

In the panel's opinion, the evidence does not support the conclusion that these findings on arthroscopy were causally related to the compensable injury. In coming to this result, we note the following:

  • With respect to the lateral meniscal tear, the panel notes that there were no findings of lateral tenderness at the outset of the claim. The reports all refer to medial joint line tenderness. We also note that by the time the worker was examined by a sports medicine physician on July 31, 2010, the joint lines were noted as "ok". The sports medicine physician's diagnostic impression was of patellofemoral pain.
  • The panel considered the orthopaedic surgeon's report of May 10, 2011 which stated: "It has been my experience that lateral meniscal tears are somewhat vaguer in their presentation on history and physical examination." While this may be the case, the panel is not satisfied that this observation overcomes the complete lack of symptoms on the lateral side in conjunction with multiple reports of medial joint line tenderness. We also place weight on the absence of joint line tenderness by July 31, 2010, which would be consistent with a healed medial side strain injury.
  • With respect to the finding of chondromalacia, the panel is of the opinion that the mechanism of injury does not support this type of injury. The worker described bending down to pick something off the ground when she felt a pull in her knee. There was no acute impact to the knee which is the type of mechanism of injury typically associated with chondromalacia.
  • Similarly, with respect to the patellar maltracking/instability, the movements described by the worker again do not support this type of injury. There was no striking or acute impact to the knee.
  • The finding of synovitis simply refers to inflammation. The finding of discoid meniscus is a congenital condition which the worker would have had since birth.

The panel is therefore unable to relate any of the findings on arthroscopy to the workplace accident. The panel accepts the opinions of the WCB medical advisor and the WCB orthopaedic specialist who indicate that the surgical findings were not consistent with early clinical findings and the mechanism of injury.

For the foregoing reasons, the panel concludes that the compensable injury of May 5, 2010 was limited to a soft tissue strain and neither caused or contributed to the need for arthroscopic surgery on January 12, 2011. As such, the worker is not entitled to further wage loss benefits. The worker's appeal is dismissed.

Panel Members

L. Choy, Presiding Officer
A. Finkel, Commissioner
P. Walker, Commissioner

Recording Secretary, B. Kosc

L. Choy - Presiding Officer

Signed at Winnipeg this 5th day of March, 2012

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