The Appeal CommissionThe Workers Compensation Act of Manitoba

As noted in the background, the worker suffered injuries to both legs while at work in January 2005. While the worker’s claim was accepted, the worker at the outset did not suffer any time loss. He later experienced increased symptoms and medical difficulties with his left knee, and is seeking to have these medical conditions accepted as being causally related to his January 2005 claim.

The Worker’s Position:

The worker argues that the WCB had underestimated the nature and severity of the crush injury he had suffered when he was attacked by the bull and pinned against a fence by the bull. He provided considerable evidence at the hearing regarding the mechanics of the injury, including photographs of the location of the accident. He notes that when the bull attacked him, he jumped onto the fourth rung of a steel gate and “that’s when it started going up and down the back of the legs, ramming my legs, trying to push me through the gate.” The bull itself weighed 2,600 to 2,800 pounds, and hit him four or five times before he was pulled over the fence by a co-worker. He landed on his hands and knees on the frozen ground on the other side of the fence. After, both legs were burning from the rubbing against the gate, and there was bruising and swelling of both legs by the next day, from the ankles to the groin. Regarding knee pain, the worker indicated “It was a burning feeling. I couldn’t really tell until later on, the clicking and that, until the swelling went down.” The swelling continued for almost a month, and it was at that time that he noticed a clicking in his left knee and saw his doctor.

The worker advises that he was to have had an arthroscopy because of his left knee problems (prior to the second incident in 2006), but it did not happen, as his orthopaedic surgeon had moved away. He indicates that his left knee continued to deteriorate and weaken throughout 2005, and wanted to pop out to the inside. It clicked when he knelt down, and he was wearing a cloth knee brace at work. In describing the 2006 injury when he stepped off the tractor and heard a pop, he indicated that his knee was already very weak, and that his symptoms after that incident were in the same place as before.

The worker advisor argues that the worker likely had a knee injury that was more severe than originally thought, and that he had continuous and increasing problems with his left knee, until the time of the 2006 incident. She argues that his already injured knee put him at risk for further injury, which should be part of the WCB’s ongoing responsibility.

Legislation

WCB Policy 44.10.80.40, Further Injuries Subsequent to a Compensable Injury provides that:

“A further injury occurring subsequent to a compensable injury is compensable:

(i) where the cause of the further injury is predominantly attributable to the compensable injury; …”

Analysis:

As noted in the background, the adjudication of this file has been complicated by the presence of two traumatic events involving the worker’s left knee/leg. The first incident involving the bull is a compensable event, and the second occurred while the worker was employed with a not-covered employer, and thus is not, if it had occurred alone, a compensable event within the meaning of the Act. WCB Policy 44.10.80.40, as noted above, does provide a limited set of circumstances where a non-compensable second event or injury could lead to it being compensable as well.

After a careful review of the evidence on file and from the hearing, the panel has concluded, on a balance of probabilities, that the first injury was significant and caused significant internal derangement, and that the cause of the second injury in 2006 is predominantly attributable to the compensable injury in January 2005. In support of this decision, the panel relies on the following observations and findings.

The panel notes that the medical information in this case is complex, as the worker’s left knee condition clearly worsened in a non-WCB-related incident in 2006, when he stepped off a tractor and heard a popping sound in his knee. Months later, he and his treating physicians suggest that his knee had already been damaged from the work incident in January 2005.

Earlier reviews of this file focus on the earliest clinical examinations which refer to lateral injuries to the worker’s left leg and knee, and the apparent lack of medial symptoms or findings in those initial examinations. Those reviews also focus, to some extent, on whether contact by the bull on the lateral aspect of the left knee could indeed lead to medial injury to the worker’s left knee.

At the hearing, the panel had the opportunity to question the worker extensively about the mechanism of injury, and has come to the conclusion that the mechanism of injury was more complex than may have been presumed at earlier levels of adjudication. The panel notes that the expanded mechanism of injury creates ample opportunities for a more severe injury than may have been previously considered.

Dealing firstly with the mechanism of injury, the panel notes and finds that:

• The attack by the bull was sudden and very violent, and there was multiple contact between the bull and the worker’s legs, including ramming against a gate and rubbing up and down the worker’s legs.
• The worker had jumped onto the lower cross-bars (rungs) of a steel gate. Thus his feet were planted during most of the collisions with the bull. The nature of the lacerations, abrasions, and bruising to both sides of both legs, calves, and ankles, as well as the specific findings in the lateral left knee, suggest that the bull hit the worker with considerable force, more than once. These clinical findings are also consistent with the worker’s evidence that he was also being pinned between the bull and fence bars, and suggests that there was direct contact on both the lateral and medial sides of the leg, either by the bull or the fence or a combination of both. The panel notes that the blows against the worker’s legs would create horizontal forces that would have had to be absorbed by the lateral and medial sides of the left knee joint, depending on the angles of the blows. These forces would have been greater when the worker’s feet were planted.
• The worker is a large man who was dragged up by a co-worker and flipped over the top of the fence to the other side, to save him from further injury. From photographs provided by the worker, the panel notes that the worker fell up to five feet to the ground, from the top of the fence. This was not a planned fall, and the worker fell onto his hands and knees from that height. The panel notes that the clinical findings in subsequent medical reports are also consistent with an awkward fall to the ground.

Dealing with the medical information on the file, the panel notes that later medical commentaries tend to focus on the 2006 tractor incident and the later appearance of symptoms on the medial side of the knee as well as diagnostic evidence of osteoarthritis on the medial side of the knee, which are contrasted with the earliest medical reports which note difficulties noted on the lateral side of the knee. The panel has reviewed the chronology of symptoms subsequent to the January 2005 incident and notes the following:

• Although the worker did not suffer any time loss from work, he did move to lighter duties for an extended period of time after the accident.
• The worker had considerable swelling and numbness for several weeks following the accident, which finally led to the worker seeing a doctor and ultimately a referral to an orthopaedic specialist.
• His left knee continued to deteriorate, he first noted clicking in his left knee within a month of the January 2005 incident, and he started to wear a cloth brace.
• An orthopaedic specialist saw the worker in October 2005, and noted the worker’s complaints, of several months duration, of increasing knee pain. The specialist confirmed a meniscal problem at that time, in particular a medial pseudo-laxity. The orthopaedic specialist proposed an arthroscopy to deal with a conjectured medial meniscus tear at that time. The arthroscopy had not been performed by the time of the second incident in 2006, at which time the medial meniscal tear became a definitive diagnosis.

As to the relationship between the mechanism of injury and the worker’s current left knee condition, the panel makes the following findings:

• Although the worker did have pre-existing degenerative processes in his left knee, they were asymptomatic prior to the accident and the worker did not have any medical treatment for same. As the swelling and numbness dissipated several weeks later, the worker noted clicking in his left knee for the first time.
• The worker suffered multiple blows to both legs, as well as a significant fall. The forces or awkward positions of these events suggest a mechanism of injury that could lead to internal derangement to either a healthy knee, or to a knee with pre-existing problems.
• The worker’s evidence regarding the steadily worsening left knee is supported by his attending physician’s reports, and in particular by his orthopaedic surgeon who identified ongoing acute medial-side knee problems in October 2005, several months prior to the second incident in February 2006.

Based on these findings, the panel concludes that the worker’s left knee difficulties are, on a balance of probabilities, causally related to the January 2005 compensable injury.