The Appeal CommissionThe Workers Compensation Act of Manitoba

Applicable Legislation

The Appeal Commission and its panels are bound by The Workers Compensation Act (the “Act”), regulations and policies of the Board of Directors. This case deals with ongoing entitlement to benefits for a worker with a pre-existing condition.

Under subsection 4(2) of the Act, a worker who is injured in an accident (as defined under the Act) is entitled to wage loss benefits for the loss of earning capacity resulting from the accident. 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.

The Board of Directors has established policy 44.10.20.10, Pre-existing Conditions, which deals with injuries that involve pre-existing medical conditions. It provides, in part, as follows:

1. WAGE LOSS ELIGIBILITY

(a) Where 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.

(b) Where 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 an

accident 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.

…

B. DEFINITIONS

1. Aggravation: The temporary clinical effect of a compensable accident on a pre-existing condition such that the pre-existing condition will eventually return to its pre-accident state unaffected by the compensable accident.

2. Enhancement: Where a compensable injury permanently and adversely affects a pre-existing condition or makes necessary surgery on a pre-existing condition.

3. Pre-existing Condition: A condition that existed prior to the compensable injury.

Worker's Position

The worker was represented by her union representative who made a presentation on her behalf. The worker answered questions posed by her representative and the panel.

The worker's representative acknowledged that the worker has pre-existing osteoarthritis in her right knee but that this condition was symptomatic only on an intermittent basis. He submitted that the pre-existing condition had not been disabling prior to the workplace incident on December 30, 2006. He noted there was very little reference to the worker's right knee prior to the December 30, 2006 workplace injury. The representative submitted that the temporal relationship between the December 30, 2006 workplace injury and the worsening of the worker's condition can't be overlooked and result in a conclusion that this workplace injury resulted in the meniscal tears.

The representative contrasted the reports from an orthopaedic surgeon who assessed the worker on December 21, 2006, 9 days before the workplace injury, and the physician's assessment of January 10, 2007. In the prior assessment, the physician noted probable osteoarthritis in her right knee but did not note any signs of meniscal tears or recommend any action to address the osteoarthritis in her knee. In the subsequent assessment, the physician noted signs of an acute injury which he ascribed to probable meniscal tears.

The representative also noted that the worker attended at an urgent care facility on December 31, 2006 and that the examining physician noted probable meniscal tear.

The representative noted that the worker saw her family physician on January 9, 2007 who diagnosed a probable meniscal tear. He noted that this physician had not previously made this diagnosis.

The representative also noted that the worker attended another orthopaedic specialist on May 9, 2007 and that he opined "…the injury the patient suffered in December 2006 on the balance of probabilities most likely resulted in a significant tear of the menisci of her right knee…It should be noted that a tear of the meniscus does not necessarily require a violent injury to the knee…Just twisting the knee at times or getting up from a squatting position can result in a tear of the meniscus…" In his August 18, 2007 report the physician commented that while the workplace injury is not wholly responsible for the deterioration of her knee, it is partially responsible.

The representative concluded that when all the evidence is taken into consideration, the weight of evidence supports the conclusion that the worker suffered a meniscal tear in her right knee on December 30, 2006, which required surgery.

The worker answered questions about the workplace accident, described her work station duties and demonstrated the movements which caused the injury. The worker indicated that while seated on a stationary chair without arms, she reached to a counter on the right, her knee clicked three times, and she immediately experienced pain.

Employer's Position

The employer was represented by legal counsel who made a presentation on behalf of the employer. The counsel advised that the employer agrees with the WCB's position.

The employer's legal counsel submitted that information on file regarding the worker's right knee prior to the workplace accident indicates that the knee was symptomatic. He referred to the worker's hand written note, a report from her family physician, a report from an orthopaedic surgeon and various other references in the file.

In supporting the WCB's decision, legal counsel relied upon the opinions of three WCB medical advisors who were consulted by the WCB, specifically:

· WCB medical advisor who provided memos dated March 6, 2007, June 11, 2007 and March 18, 2009 and opined that the workplace injury of December 2006 was unlikely to cause a degree of damage to the pre-existing condition of the worker's right knee such that significant disability and the need for surgery would result.

· WCB orthopaedic consultant who provided a report of April 15, 2009 and opined that the claimed compensable injury of December 30, 2006 did not result in new pathology or aggravation/enhancement of pre-existing pathology requiring arthroscopy.

· WCB orthopaedic consultant who provided a report of June 3, 2010 and opined that the probable diagnosis of the compensable injury was a strain of an osteoarthritic right knee, rather than a meniscal tear or enhancement of the pre-existing osteoarthritis.

Analysis

There are two issues before the panel. The first issue is whether the December 30, 2006 workplace accident resulted in an enhancement of the worker's pre-existing right knee osteoarthritis. For the worker's appeal to be successful the panel must find that the workplace accident enhanced the worker's pre-existing knee condition. The panel was not able to make this finding.

The second issue before the panel is whether the worker is entitled to wage loss benefits and services beyond March 13, 2007. For the worker to be successful on this issue, it is necessary that the panel find that the workplace injury had not resolved as of that date resulting in the need for wage loss and other services. The panel was not able to make this finding.

The worker's representative argued that the temporal sequence cannot be ignored, especially when one considers the lack of evidence prior to the workplace injury that would indicate a severe problem in the worker's right knee. While the temporal sequence is somewhat compelling, the panel finds that there is evidence of the significant degenerative nature of the worker's right knee prior to the workplace injury and rejects this argument. The panel notes the Doctor's First Report prepared by the worker's family physician who examined her knee on January 9, 2007. The physician refers to recurrent pain and swelling and clicking the past 12 months in the right knee. The panel also notes the report of the orthopedic surgeon who examined the worker on December 21, 2006, nine days prior to the workplace accident. The physician found the worker's right knee to be suffering from progressive patellofemoral arthritis and medial compartment arthritis. The panel finds this evidence that the worker's right knee was symptomatic prior to the workplace injury confirms the severity of the right knee problem.

In reaching the above conclusions, the panel considered the mechanism of injury described by the worker at the hearing and in the file. The panel is unable to find that the minimal amount of movement in turning to the right, as demonstrated at the hearing, is capable of causing the significant injury to the menisci or to the other medical conditions present in the knee as identified in the subsequent surgery. In the panel's opinion, the movement of the right knee was very slight and did not involve weight bearing. It was much less significant than many of the activities the worker would be involved with in daily living.

The panel accepts the opinion of the WCB orthopaedic consultant set out in a memo dated June 3, 2010. The orthopedic consultant wrote:

"The description of symptoms that occurred on 30 December, 2006, is that sudden exacerbation of pain of the right knee occurred when turning on a chair towards the right side, accompanied by a sensation of three clicks in the knee. Assuming the feet were firmly on the floor, such a motion typically done hundreds of time by office workers each day and would be expected to cause a mild varus strain at the right knee and slight internal torsion of the tibia relative to the femur…In an osteoarthritic knee, motions such as this would be expected to increase symptoms, as would such everyday motions as rising from a chair, walking on the level, or stepping up a stair. It is improbable that such a motion would cause tears in both menisci, even though the menisci were degenerative. It is more probable that the degenerative tearing of both menisci was the result of repeated ongoing fragmentation as part of the degenerative process."