Decision #70/16 - Type: Workers Compensation
Preamble
The worker is appealing the decision made by the Workers Compensation Board ("WCB") that the anterior cruciate ligament tear in his right knee was not related to the July 2, 2010 compensable accident. A hearing was held on March 17, 2016 to consider the worker's appeal.
Issue
Whether or not the worker's anterior cruciate ligament tear of the right knee is related to the July 2, 2010 compensable accident.
Decision
That the worker's anterior cruciate ligament tear of the right knee is related to the July 2, 2010 compensable accident.
Decision: Unanimous
Background
The worker filed a claim with the WCB for injury to his right knee that occurred on July 2, 2010. The worker reported that he went to his work station after coffee break at 6:00 p.m. and when he bent his knee to get onto the stand, he felt a crack and pain on the posterior aspect of his knee.
The Employer's Accident Report noted the worker had reported he bent his knee trying to get on the stand and felt a cramp and a pain. It occurred after coffee break when he set his ergonomic stand to the correct height. He reported to the health unit immediately. The employer noted they had concerns with the mechanism of injury.
A WCB adjudicator spoke with the worker on July 27, 2010 to discuss his claim. Regarding the mechanism of injury, the worker indicated that he went to the line and tried to pull up a stand to reach the line. When he tried to pull it up, he put his knee straight and it cracked. He started to feel pain on the knee. He went down to pick up the stand to pull it up into place. He bent down, and on his way up he felt a crack in his knee.
The worker's claim for compensation was accepted based on the diagnosis of a right lateral hamstring strain. File records showed that the worker continued to work his regular duties and that a physiotherapist outlined specific restrictions with respect to the compensable injury.
On September 21, 2010, the treating physiotherapist reported to the treating physician that the worker continued to report knee pain symptoms along the posterolateral aspect of the right knee and that the pain symptoms were aggravated with full squatting or running. The examination findings showed that the worker had tenderness to palpation of the distal aspect of the right biceps femoris. McMurray's and directional stress tests were unremarkable.
On February 15, 2011, the worker underwent an MRI assessment of his right knee. The imaging results showed a complex tear of the body and posterior horn of the medial meniscus with meniscal cyst. There was a suspected partial-thickness tear of the proximal attachment of the anterior cruciate ligament ("ACL"). The ACL was smaller than expected. There was also a small Baker's cyst.
A WCB medical advisor reviewed the file information on March 20, 2011 at the request of case management and stated:
The probable diagnosis at the time of injury was a knee sprain;
The current diagnosis was a complex tear of the meniscus with tear of the posterior horn of the meniscus. The ACL was questionable in relationship to the injury and would be resolved after further medical treatment;
The current medical report was limited but the worker had pain with mild restricted range of motion but was seemingly able to continue without time loss.
In a report to the family physician dated June 23, 2011, an orthopedic surgeon reported that the worker was seen for his right knee complaints. The surgeon noted that the worker had ongoing medial sided knee pain and a catching sensation. He said an MRI showed a complex medial meniscus tear as well as a possible partial ACL tear. The surgeon recommended arthroscopy to repair the medial meniscus tear.
On July 28, 2011, a WCB medical advisor wrote the treating surgeon to advise that the WCB was accepting responsibility for arthroscopic surgery directed at the right medial meniscus, but did not accept responsibility for any other procedures performed during the right knee arthroscopy, which included the suspicion of an ACL tear.
On August 12, 2011, the worker underwent surgery to his right knee. The post-operative diagnosis was: Medial meniscus tear and complete ACL tear, and chondromalacia medial femoral condyle.
In a letter dated October 4, 2011, the worker was advised that the WCB was unable to pay for the costs associated with a recommended knee brace for the ACL tear, as the WCB only accepted responsibility for the right medial meniscus injury.
On October 19, 2011, a WCB medical advisor stated:
Based on report from OS (orthopedic surgeon) worker has made a good recovery from surgery. The worker is now to have brace for non compensable complaint. No restrictions for CI (compensable injury). At this time any restrictions are related to non compensable complaint.
On October 20, 2011, the worker was advised that based on the WCB medical advisor's opinion and reports from his treating surgeon, the WCB was of the view that he had functionally recovered from his compensable right knee injury and that no further work restrictions were recommended. The WCB also was of the view that the use of a brace and any current restrictions were related to his non-compensable injury (ACL tear).
On March 3, 2012 the worker underwent right knee ACL reconstruction and a partial medial meniscectomy. The post-operative diagnoses were a right ACL tear and a medial meniscus tear.
On June 19, 2012, legal counsel submitted medical reports from an occupational health physician dated January 6, 2012 and a second orthopedic specialist dated May 16, 2012 to support that the worker's ACL tear was related to the mechanism of injury that occurred in July 2010. (The panel notes that the first page of the May 16 letter is dated May 16, 2011, but should say May 16, 2012.)
In his letter dated January 6, 2012, the occupational health physician stated:
The mechanism of injury in the July 2010 incident involved high force and torque applied across a flexed knee; ACL tears often accompany medical (sic) meniscus tearing injuries, so I disagree with the position taken by the WCB that they are not responsible for the ACL diagnosis. There is no pre-existing knee pathology that contributes to his knee condition.
In his letter of May 16, 2012, the second orthopedic specialist stated:
From the history given by the patient and from the MRI findings, it is entirely possible that he sustained the medial meniscal tear and also the ACL partial tear at the time of his injury whilst he was on the job for the (employer). As a result, I would say that both injuries should be covered under the Worker's Compensation Claim.
On June 21, 2012, a WCB orthopedic consultant stated:
It was accepted that the medial meniscus tear arose out of the workplace injury and from which the claimant has made a full recovery. There were no medical findings by way of claimed symptoms or physical examination to suggest any relationship between the workplace and the arthroscopically identified ACL tear of the right knee joint.
Current treatment is addressed to the surgical reconstruction of the right ACL and is not a responsibility of the WCB.
...The claimant had fully recovered from the surgical treatment of the accepted diagnosis of the compensable injury, torn medial meniscus, by October 2011, three months after the surgical treatment.
In a decision dated July 4, 2012, the worker was advised that the WCB was unable to accept responsibility for wage loss and medical aid benefits in relation to his right knee ACL tear as it was not related to his compensable accident.
In May 2013, the worker contacted the WCB to advise that he underwent surgery to both knees on April 29, 2013. The worker denied any new injuries to his right knee since the July 2010 accident. He said his left knee became injured due to "putting extra pressure on it for a long time" when walking with a limp due to his right knee problems.
On May 16, 2013, the WCB case manager referred the claim file to the WCB's healthcare branch to obtain medical advice regarding the worker's bilateral knee condition. On May 31, 2013, the WCB orthopedic consultant stated:
There is no change in my opinion of June 21, 2012, regarding the right knee joint. There is no continuing relationship between the original compensable diagnosis and the current status of the right knee joint.
With respect to the left knee joint, there is no report of a subsequent workplace injury or other injury outside of the workplace. The suggestion that the pathology identified at arthroscopy was related to increased weight bearing on recovery from the right knee ACL reconstruction is speculative at best, and if so would relate to treatment identified as unrelated to the compensable injury of this claim.
In a letter dated July 12, 2013, the worker was advised that his current right and left knee diagnoses were not related to the original workplace injury of July 2, 2010. There was no entitlement to wage loss or medical aid benefits.
On September 23, 2013, legal counsel filed an appeal with Review Office that the injury to the ACL occurred at the same time as the compensable right knee meniscus tear.
On October 30, 2013, the employer's advocate submitted to Review Office that "we do not believe that any of [the worker's] bilateral knee problems are related to the reported July 2, 2010 workplace injury, including the complex degenerative medial meniscal tear of the right knee. We ask that you review the decision to accept the medial meniscal tear as well. At most, we believe that [the worker] sustained a temporary aggravation of a pre-existing degenerative condition."
On November 28, 2013, Review Office determined that the compensable injury sustained on July 2, 2010 involved a right medial meniscus tear and not an ACL tear. Review Office stated it was unable to accept the medical opinions outlined by the occupational health physician and the second orthopedic surgeon that the worker sustained a medial meniscus tear and ACL tear at the same time, and that ACL tears often accompany medial meniscus tear injuries.
Review Office accepted the WCB medical opinions dated June 21, 2012 and May 31, 2013. Review Office referred to the August 12, 2011 operative report which stated there was Grade III chondromalacia of the medial femoral condyle which was debrided/shaved. It found this to be a pre-existing condition which was not caused, aggravated or enhanced by the compensable injury based on the mechanism of injury.
Review Office also stated that it did not find a review of the evidence supported a change to the original acceptance of the medial meniscus tear in relation to the July 2, 2010 accident.
On August 10, 2015, the worker's legal counsel appealed Review Office's decision to the Appeal Commission and an oral hearing was arranged.
Reasons
Applicable Legislation and Policy
The Appeal Commission and its panels are bound by The Workers Compensation Act (the "Act"), regulations and policies of the WCB's Board of Directors.
Subsection 4(1) of the Act provides that 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.
WCB Policy 44.10.20.10, Pre-existing Conditions, sets out the following definitions:
Aggravation: The temporary clinical effect of a compensable injury on a pre-existing condition such that the pre-existing condition will eventually return to its pre-accident state unaffected by the compensable injury.
Enhancement: When a compensable injury permanently adversely affects a pre-existing condition.
Worker's Position
The worker was represented at the hearing by legal counsel who made a presentation on the worker's behalf. The worker answered questions from the panel with the assistance of an interpreter. A workplace union representative was also in attendance, and provided evidence with respect to the plant operations.
It was submitted that the worker's job on the product line is physically rigorous and fast-paced. As such, workers rotate from one work station to another every two hours. At each work station, there is a metal stand which has to be adjusted up or down based on the workers' height. Workers stand on them with product moving past them at considerable speed on a conveyor belt.
At the hearing, the worker provided a further description of the stands and the circumstances of the July 2, 2010 accident. He said that the stands have a sturdy metal base and a metal platform which has to be pulled up and down. Pins are placed in holes on each side of the stand to hold the platform in place at the appropriate height. The stand and platform weigh 21 kilograms. The worker said that the stands are all different. The janitors take them away at night and clean them. Sometimes the pins get stuck or are too tight, and the platforms are sometimes put back on the wrong base where they do not fit as well. It is sometimes too hard for one person to adjust the height of the stand, and it takes two people to adjust it.
The union representative explained that the stands are removed from the line at the end of the day and not always returned to the same spot. The stands have to be sturdy to support workers of different weights. Not every platform goes into the same stand every day, so the stand can become twisted. The stands are cleaned with chemicals, which get stuck underneath, making it tougher to move the platform.
The worker explained through the interpreter that the stands usually have two handles, one on either side of the platform, which they use to lift it up. The stand that he was trying to adjust when he was injured, however, had a handle on the left side only, and was missing the right side handle. The pins were too tight and were stuck, and he was struggling to loosen the platform to raise it. He needed to raise it so that it was approximately one foot high. When he was unable to move the platform, the worker tried to shake it to get it unstuck. He was crouching down, almost into a squat, with his buttocks at basically the same height as his knees. He was in that position for about five seconds, with the stand in front of him, trying to shake it and lift it, using his hand and the one handle, but the platform would not move. He said that was when he felt the pain in his knee, indicating that it was towards the side and the back, and heard a crack.
The worker felt more pain as he stood up. He could not get up on the stand after that or finish what he was doing. A co-worker noticed and asked him what had happened, and at that point he spoke to the lead hand who took him to the nurse's station. He said he was limping badly on the way to the nurse's station. His knee started to swell right away and the back of the knee was purple. At the nurse's station, he explained what had happened using his broken English and signs and symbols. They put an ice pack on his knee. He stayed in the nurse's station for about 15 minutes, then went back to work. When he moved on to the next work station, his co-worker helped him adjust the stand. He had to put more ice on his knee when he went home. The ice did not take the swelling down, but it relieved the pain a little.
The worker said that he continued working because he had a family to support. He was able to manage because he had help all the time. He could not walk to the bus stop to take the bus, so his wife or a co-worker drove him to work. Co-workers helped him every day with adjusting the stand. He could not bend, and would mostly use his arms and the upper part of his body when working. He went to the nurse's station every day to get ice for his knee. He was very slow climbing stairs, going up each step with the left foot first then bringing his right foot up. When he tried to put weight on his right knee, he felt that it was loose and moving, that it would not stay in place.
He said that he could not do anything like a normal person because of the pain and pulling. Every movement was hard because of the pain. He had difficulty bending or walking even short distances. He could not run or do any kind of sport. It was difficult or complicated for him to do regular daily activities, such as taking a bath. He could not play with the baby or do things to help her.
Counsel submitted that, based on his research, roughly 50% of ACL injuries occur at the same time as meniscus injuries. The worker had no past knee injuries and was in good health. He submitted that the trauma, the mechanism of the injury, the weight of the stand, the twisting and turning to get it up, could very well have caused the ACL, and in fact, for the most part, the physicians agreed with that. The literature indicates that the signs and symptoms of an ACL injury usually include a loud pop or popping sensation, and the worker indicated that he heard a crack. While he was able to continue working, he was not working his full regular duties, as he had assistance. There were difficulties and he was in pain.
In conclusion, based on the worker's medical history, the 2011 MRI, the treating orthopedic surgeon's pre-operative and post-operative diagnosis, the medical reports of the occupational health physician and the second orthopedic surgeon, and the mechanism of injury, it was submitted that on a strong balance of probabilities, the injury to the ACL occurred at the same time as the meniscus tear which was accepted by the WCB as being work-related.
Employer's Position
The employer was represented by an advocate, who provided a written submission dated March 10, 2016. In her written submission, the advocate stated that the employer's position, based on objective, clinical and diagnostic medical evidence, was that the worker did not sustain an ACL injury on July 2, 2010. It was submitted that an ACL tear requires substantial trauma to occur. From information provided immediately following injury to the employer, doctor, WCB adjudicator, and physiotherapist, this did not occur. Not only did it not occur, but the reports of the mechanism of injury were inconsistent.
It was submitted that such damage to the knee would not be expected in setting up a stand to the right height. The various descriptions of the mechanism of injury did not involve the type of motion that would lead to an ACL tear as referred to in the medical literature. It did not involve twisting, pivoting, hyperextension of the knee or sudden deceleration.
It was also submitted that clinical examination did not confirm an ACL injury. Initial reports did not show any instability, just mildly restricted range of motion. This was not consistent with an ACL tear. If the worker had sustained a full tear of the ACL at the time of the workplace incident, one would have expected him to have experienced difficulties. The worker was able, however, to continue working his full, regular duties, following injury, and to do activities such as squatting and running, which are normally impossible with a full ACL tear.
The advocate asked that the panel accept the clear and unequivocal opinion of the WCB orthopedic specialist provided June 21, 2012. She noted that the WCB specialist indicated that the ACL tear identified on arthroscopy did not have any relationship to the workplace injury, and that only the right medial meniscal tear arose out of the workplace injury, although the specialist appeared to question that as well. The advocate recognized that English was not the worker's first language, but added that the employer reported that his communication was adequate, that the adjudicator did not express any difficulty in obtaining a mechanism of injury from him, and that he was able to provide descriptions of the mechanism of injury to his healthcare providers. In conclusion, the employer asked that the appeal be denied.
Analysis
The issue before the panel is whether the worker's anterior cruciate ligament tear of the right knee is related to the July 2, 2010 compensable accident. For the worker's appeal to be successful, the panel must find, on a balance of probabilities, that the worker's ACL tear arose out of and in the course of his employment. Having reviewed all of the evidence, the panel was able to make that finding.
The panel spent a considerable amount of time at the hearing exploring the configuration and condition of the stand the worker used, and the worker's movements and symptoms. The evidence from the hearing, including that of the union representative, provided us with much more detail and a deeper understanding of the mechanism of injury than was previously available on the claim file.
The panel notes that the evidence disclosed that the worker was down in almost a full squat, and was lifting up and shaking the platform of the stand back and forth to try to get it loose and raise it. The worker heard a crack near his knee and felt pain. The worker went from being able to work to limping badly, with a swollen knee, and being substantially limited in his normal ability to function.
The panel is satisfied that this detailed mechanism of injury is consistent with the findings of a medial meniscus tear, which was accepted by the WCB as being compensable.
Regarding potential mechanisms of injury that might cause an ACL tear, it is the panel's understanding that ACL injuries are most commonly associated with external rotation, hyperextension, deceleration, and rotational movements of the knee. Common first symptoms include giving way or buckling of the knee or an audible popping in the knee.
The panel finds the significant forces and rotational torqueing of the knee which were involved in the detailed mechanism of injury are consistent with the types of forces and movements which result in an ACL tear.
The panel also notes that the report of the arthroscopic surgery on August 12, 2011 revealed significant degenerative conditions in the worker's right knee, including Grade 3 chondromalacia which the panel understands would not have come on quickly or been brought on by the accident. While asymptomatic, these would nevertheless have been pre-existing conditions.
Based on the evidence and the worker's detailed description of his mechanism of injury, the panel finds on a balance of probabilities, that the July 2, 2010 accident resulted in a significant change and enhancement in the degenerative condition of the worker's ACL which ultimately required surgery.
In coming to its conclusion, the panel places significant weight on the May 16, 2012 opinion of the orthopedic specialist that it was entirely possible that the worker sustained the medial meniscus tear and the ACL partial tear at the time of the July 2010 injury. The panel recognizes that there are differences in the specialist's description of what happened, in particular with the reference to the worker lifting a series of weights of 15 to 20 pounds, but notes that the weight the specialist referred to is much less than the almost 50 pound weight of the platform which was described at the hearing, and therefore, in the panel's opinion, has little or no impact on the opinion itself.
Based on the totality of the evidence, and on the balance of probabilities, the panel finds that the worker's anterior cruciate ligament tear of the right knee was related to the July 2, 2010 compensable accident.
The worker's appeal is allowed.
Panel Members
M. L. Harrison, Presiding OfficerA. Finkel, Commissioner
P. Walker, Commissioner
Recording Secretary, B. Kosc
M. L. Harrison - Presiding Officer
Signed at Winnipeg this 13th day of May, 2016