The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker is appealing the decision made by the Workers Compensation Board ("WCB") that she is not entitled to further benefits in relation to her June 7, 2016 accident. A hearing was held on December 13, 2018 to consider the worker's appeal.

Issue

Whether or not the worker is entitled to further benefits in relation to the June 7, 2016 accident.

Decision

That the worker is not entitled to further benefits in relation to the June 7, 2016 accident.

Background

The worker reported that she injured her left knee in a workplace incident on June 7, 2016, which she described as follows:

Around 8:30am all I did was grab a breakfast tray off the cart, it wasn't heavy, in the dining room, I took a step backwards and went to turn around and felt a pop in my knee. I didn't trip on anything.

I didn't finish my shift today.

The worker saw a physician on June 7, 2016. The physician noted that the worker reported "She was just managing a tray when she turned and felt a bit of a pop and has had a pain in her knee since. She doesn't recall major problems with that same knee in the past." The physician noted objective findings of "a minor effusion" and "Her ligaments still appear intact. A bit of tenderness on stressing both menisci lateral and medial. Overall weight bears." The worker was diagnosed with a knee strain and referred for an x-ray. The results of the x-ray, taken June 9, 2016, were that "No bone or joint abnormality is seen at the left knee joint."

The worker attended an initial physiotherapy assessment on June 17, 2016. The physiotherapist diagnosed a left knee medial collateral ligament (MCL) sprain, a possible meniscus injury and patellar cartilage irritation.

The WCB accepted the claim and wage loss and medical aid benefits commenced.

The worker participated in a graduated return to work program beginning June 22, 2016, and returned to her full-time regular duties as of August 22, 2016.

On September 1, 2016, the case manager advised the worker that her file would be closed the following week, unless she called back, and asked that the worker call back if she had any concerns. By letter dated September 7, 2016, the WCB advised the worker that file information showed she was working her regular job duties and was no longer seeking medical treatment for her compensable injuries, and they would take no further action on her claim as a result.

On April 19, 2017, the worker contacted the WCB and advised that on March 18, 2017, she felt something "pop out the back of her knee and then back in place again." She noted that the pain felt significantly worse, her knee swelled immediately and felt unstable. The worker said she saw her physician on March 27, 2017 and had an MRI on April 12, 2017.

The April 12, 2017 MRI of the worker's left knee showed a "Chronic, complete tear of the posterior cruciate ligament."

The worker attended an initial physiotherapy assessment on April 24, 2017. The worker advised the physiotherapist that she continued "to have episodes of shifting/buckling dating back to work injury last year." The worker further reported that she had a "shift" in her knee in mid-March, that her knee buckled backwards and reduced spontaneously, and she had pain and swelling for 24 to 36 hours then it resolved. The physiotherapist diagnosed the worker with a "PCL full tear - unstable knee."

On May 5, 2017, a WCB medical advisor reviewed the worker's claim and provided an opinion to file.

On May 9, 2017, Compensation Services advised the worker that they were unable to accept responsibility for the complete tear of her PCL and she was not entitled to further benefits. Compensation Services cited the WCB medical advisor's May 5, 2017 opinion, in part, as follows:

…The PCL is a thick, strong ligament. It takes powerful force to tear it. This is most commonly seen after a direct blow to the front of the lower leg, particularly when the knee is bent - such as in a motor vehicle accident or in a contact sport like football.

The MOI [mechanism of injury] did not involve the degree of force required to acutely tear the PCL. The worker did not present after the workplace accident with clinical findings of a tear…

An acute PCL tear presents with characteristic findings (the posterior sag and false positive ACL testing). The worker saw a physio several times with this injury and he did ligament testing and never documented any PCL laxity. If the PCL tear happened acutely in June 2016 it would have been expected that the therapist would have noticed the clinical findings associated with it at least by the end of the treatment.

Compensation Services determined that given the mechanism of injury, the accepted diagnosis, the treatment to date and all the medical findings reported, they were unable to relate the worker's PCL tear to her June 7, 2016 injury.

On April 6, 2018, the worker's union representative submitted further medical evidence and requested that Compensation Services reconsider their decision. The representative noted disagreement with the WCB medical advisor's opinion that the workplace accident could not have caused a PCL tear due to a lack of force. He submitted that the worker's treating physician and an orthopedic surgeon had both expressed that the worker's reported medical history was consistent with the development of a PCL tear. He noted that there was no evidence the worker had ever had any other traumatic injuries to her left knee, and while she had improved with treatment, she had experienced persistent symptoms since her workplace accident. The representative submitted that the worker was entitled to further benefits because the June 7, 2016 accident had caused a tear of the worker's PCL which was responsible for her persistent left knee symptoms and restrictions.

On May 9, 2018, the WCB medical advisor reviewed the new medical information provided and provided a further opinion to file.

On May 17, 2018, Compensation Services advised that there was no change to the May 9, 2018 decision. Compensation Services cited the WCB medical advisor's May 9, 2018 opinion, in part as follows:

…The treating practitioners have provided the opinion that since it was not known that she had a PCL tear prior to the workplace accident and an MRI showed it after the workplace accident, that the PCL tear has to be related to the CI [compensable injury].

In [treating physician's] report of October 12, 2017, he indicates that the worker has complained of instability of the knee since the workplace accident (June 7, 2016). On review of his report from June 7, 2016 and physio reports of June 17, June 30, July 14, and August 17, 2017 there was no documentation of any instability. If the accident caused an acute PCL tear, there should have been instability within that time.

The first time instability is documented in a medical report is March 23, 2017 (9 months after the accident). That time frame would not support that the PCL was acutely related to the C/I [compensable injury]…

Compensation Services concluded that after careful consideration of all the medical information presented, they were unable to accept the PCL tear in relation to the compensable injury of June 7, 2016.

On June 4, 2018, the worker's union representative requested that Review Office reconsider Compensation Services' decision. The representative noted that while the initially documented clinical findings did not suggest concern for ligament stability, the worker's healthcare providers' reports supported that a probable causal connection existed between her June 7, 2016 accident and the subsequently diagnosed PCL tear. Should Review Office not find that the evidence established the workplace accident caused a tear of the worker's PCL, the representative asked that they consider the worker's entitlement to benefits based on the likelihood that her workplace accident enhanced a previously-undiagnosed pre-existing condition.

On June 13, 2018, Review Office determined the worker was not entitled to further benefits. In arriving at their decision, Review Office placed significant weight on the mechanism of injury, the information collected in close proximity to the workplace accident and the WCB medical advisor's opinions. Review Office also quoted and placed significant weight on a June 6, 2018 opinion from a WCB orthopedic consultant, who reviewed the file and opined as follows:

Considerable antero-posterior force is usually required to cause a tear of the posterior cruciate ligament (PCL). Initial symptoms are usually of considerable pain, joint effusion, and inability to bear weight on the affected limb. After the pain and swelling and muscle protection settles, clinical signs of PCL deficiency become evident by positive posterior drawer and sag tests. That an acute tear of the PCL did not occur on 7-June-2016 is supported by:

a) The described mechanism of injury is much less than would generally be required to rupture a PCL.

b) Medical assessment on 7-June-2016 noted a minor effusion and the knee ligaments appeared intact. The worker was about to go off on vacation.

c) Physiotherapy assessment on 22-June-2016 noted lack of 15 deg extension but no instability. A diagnosis of injury of the medial collateral ligament (MCL) or medial meniscus was considered. Subsequent physiotherapy notes indicated range of motion within normal limits. No ligamentous instability was detected.

An acute tear is often seen on MRI as a defect in the PCL with proximal and distal portions detached from one another. A chronic tear after many months or years will be characterized by absorption of the remnants of the PCL, so that the PCL appears to be completely missing. The MRI report dated 12-Apr-2017 noted that the PCL was completely missing.

Review Office determined, on a balance of probabilities, that the worker sustained a left knee strain as a result of the workplace accident. Review Office was of the view that recovery from a strain occurs within of a short duration and that this was consistent with the worker being able to return to her regular duties and complete medical treatment. Review Office found that the evidence did not show that the complete tear of the PCL existed prior to, or was caused on, June 7, 2016. Review Office concluded that they were therefore unable to relate the worker's need for medical treatment and/or any time loss from work to the June 7, 2016 compensable injury.

On June 25, 2018, the worker's representative appealed the Review Office 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.

Under subsection 4(2), a worker who is injured in an accident is entitled to wage loss benefits for the loss of earning capacity resulting from the accident, but no wage loss benefits are payable where the injury does not result in a loss of earning capacity during any period after the day on which the accident happens.

Subsection 27(1) of the Act provides that the WCB "…may provide a worker with such medical aid as the board considers necessary to cure and provide relief from an injury resulting from an accident."

Subsection 39(2) of the Act provides that wage loss benefits are payable until such time as the worker's loss of earning capacity ends or the worker attains the age of 65 years.

WCB Policy 44.10.20.10, Pre-Existing Conditions (the "Policy") addresses the issue of pre-existing conditions when administering benefits. The Policy states that:

The Workers Compensation Board (WCB) will not provide benefits for disablement resulting solely from the effects of a worker's pre-existing condition as a pre-existing condition is not "personal injury by accident arising out of and in the course of the employment." The WCB is only responsible for personal injury as a result of accidents that are determined to be arising out of and in the course of employment.

With respect to wage loss eligibility, the Policy states, in part:

When 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 compensable injury 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.

The following definitions are set out in the Policy:

Pre-existing condition: A pre-existing condition is a medical condition that existed prior to the compensable injury.

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 by a union representative, who provided a written submission in advance of the hearing and made an oral presentation to the panel. The worker responded to questions from her union representative and from the panel.

The worker's position was that she is entitled to further wage loss and medical aid benefits in relation to her left knee condition because the available evidence supports that her ongoing symptoms and restrictions are, on a balance of probabilities, a direct result of her June 7, 2016 workplace accident.

The worker's representative submitted that while a forceful injury is typically required to tear the PCL, force is not necessarily required in all cases. The representative submitted that this was implied by the wording used by the WCB orthopedic consultant. Medical literature included with his written submission also indicated that a twisting injury or a simple misstep, both of which were consistent with the worker's reported mechanism of injury, can cause a PCL tear.

The representative noted that the medical literature also explained that pain and swelling occurring soon after an injury, along with swelling that causes stiffness of the knee, difficulty walking, and the feeling of instability are typical symptoms of a PCL tear, and that this clinical presentation is similar to the initial assessment of the worker's knee. He noted that although the initial treatment providers did not document findings indicative of a PCL tear, a PCL tear is a less common injury and more difficult to diagnose. The representative also noted that the WCB's orthopedic consultant had stated that the clinical signs of a PCL tear would only be apparent once the pain, swelling and muscle protection settled.

It was submitted that the worker's knee was never the same after her injury. Her symptoms and function improved sufficiently to enable her to gradually return to her pre-accident duties, but she continued to have issues with her knee popping and giving way, along with a sense of instability, and she had to be careful. The worker stated at the hearing that when she returned to work, she needed help with some tasks, notably pushing wheelchairs, and would refuse to do things she did not feel comfortable doing. The worker said she talked to co-workers about her knee and the difficulties she was having at work. The representative noted that statements provided by some of the worker's co-workers corroborated her complaints. It was submitted that the fact that the worker was asking for help and making complaints supported that she had never fully recovered and still had a residual injury. It was submitted that the worst instance of this instability was the incident on March 18, 2017, which caused her to seek medical attention. Her treating physician made note at that time of the worker's "increasing difficulties" and the subsequent MRI revealed her PCL tear.

The worker's representative noted that while the WCB medical advisors opined that a forceful injury was typically required, the worker maintained she never had such an injury and there is no evidence of such an injury since her 2016 workplace accident. In spite of the lack of force, the worker's treating physician and orthopedic surgeon provided letters supporting that the mechanism of injury likely caused the tearing of the worker's PCL.

The worker's representative further noted that while the WCB medical advisor opined that the MRI supports that the worker's tear was longstanding and had taken months, if not years, to develop, the MRI was not done until ten months after the accident. He submitted that this could account for the chronic appearance of the findings, as findings which would have appeared to be acute at the time of the accident would no longer appear to be so.

The worker's representative submitted that if the worker's torn PCL was not directly caused by the June 7, 2016 workplace accident, the worker likely had an underlying pre-existing condition which was enhanced by the accident. The representative stated that from his perspective, it was most likely that there was some pre-existing degenerative condition or structural problem in the worker's knee to begin with, which was made worse or enhanced by the accident. The accident resulted in the knee becoming symptomatic and being consistently symptomatic thereafter. The representative submitted that the accident caused the tear or tearing, which got progressively worse, and was responsible for the recurrent symptoms the worker experienced in the workplace.

In conclusion, it was submitted that given the WCB orthopedic consultant's opinion that the PCL tear as seen on the MRI was likely several months old, and the worker's consistent report that she had no issues with her left knee prior to June 7, 2016, it was reasonable to conclude that the tear was either caused, or made worse, by the workplace accident. The representative submitted that in either event, there is a probable relationship between the June 7, 2016 workplace accident and the worker's ongoing difficulties, and the worker is entitled to further wage loss and medical aid benefits.

Employer's Position

The employer did not participate in the appeal.

Analysis

The issue before the panel is whether or not the worker is entitled to further benefits in relation to the June 7, 2016 accident. For the worker's appeal to be successful, the panel must find, on a balance of probabilities, that the worker sustained a further loss of earning capacity and/or required further medical aid as a result of her June 7, 2016 workplace accident. The panel is unable to make that finding.

The worker's claim has been accepted as a left knee sprain. The panel notes that a number of different diagnoses and injuries were identified following the June 7 accident with respect to the worker's left knee. The panel accepts that the worker may have suffered more than a sprain injury on June 7, 2016, but is unable to find that she suffered a PCL injury or tear at that time.

With respect to the PCL tear, the panel notes that there was an absence of subjective complaints or clinical findings regarding a PCL injury in the medical reports following the accident. The treating physician on the date of the accident reported that the worker's "ligaments still appear intact." The initial physiotherapy assessment report, dated June 17, 2016, shows that the physiotherapist was testing the knee ligaments, reported pain with the MCL stress test only and noted no laxity. The August 17, 2016 physiotherapy report, more than two months after the accident, refers to "Ligament tests - mild discomfort with MCL stress test", and does not mention laxity in any ligaments or instability.

The panel is satisfied that the evidence indicates that with treatment, the worker's symptoms and left knee injuries had resolved by the time her file was closed in September 2016. The panel notes that in the final physiotherapy report to the WCB prior to the worker's return to full duties, dated August 17, 2016, the physiotherapist indicates that the worker should be "cautious" with push/pull of heavy carts and heavy transfers, and can return to her regular duties on August 22, 2016. No restrictions were provided and the file was closed a little more than two weeks later.

While the worker stated that she had ongoing pain and symptoms and difficulties following her return to work, there is an absence of documentation from September 2016 to March 2017 to support her assertions. At the hearing, the worker said that she would have help and would refuse at times to do certain tasks. She said that she "would just say I'm not comfortable with that, that's going to hurt" or "I don't feel I can do that right now" and added that it depended on who she was working with. The panel notes that while the worker may not have been doing her full duties at all times as she returned to work, the evidence indicated that her symptoms and functional abilities had improved. The worker acknowledged at the hearing that she did not have any restrictions when she returned to her full-time regular duties.

Information on file and at the hearing further indicates that the worker did not see her treating physician for her knee or knee issues between September 2016 and March 2017, although she did see her physician a few times for other issues. The worker said she borrowed a brace from a co-worker which she found helpful, but did not seek medical treatment. If the worker was having ongoing issues with her knee, the panel would have expected her to seek medical attention in respect of those issues or to raise them with her physician when she saw her.

The worker's representative has suggested that the March 18, 2017 incident was more evidence of the worker's ongoing issues with her knee. The panel notes, however, that the worker's symptoms in March 2017, as she described them, were new and different from her symptoms following the June 7, 2016 accident. The worker described the March 18, 2017 incident, stating that she bent down to grab supplies off a cart and her knee "popped out the back and I stood straight up and it went right back in." She said that this had never happened before. Any time prior to March 18, 2017, she had felt that her knee was shifting from side to side, but on March 18 it went front to back. The panel notes that the mechanism of injury from the June 7, 2016 accident involved rotational forces as opposed to the back and forth forces involved in the March 18, 2017 incident.

The April 12, 2017 MRI of the worker's left knee showed a "Chronic, complete tear of the posterior cruciate ligament." The panel is satisfied, on a balance of probabilities, that the tear to the worker's PCL pre-dated her workplace accident. The panel understands a chronic complete tear to be a remote tear that would have occurred much earlier. The panel places weight on the opinion of the WCB orthopedic consultant who stated that "An acute tear is often seen on MRI as a defect in the PCL with proximal and distal portions detached from one another. A chronic tear after many months or years will be characterized by absorption of the remnants of the PCL, so that the PCL appears to be completely missing." The consultant went on to state that the April 12, 2017 MRI report noted that the PCL was completely missing. While the worker's representative has suggested that the chronic appearance of the tear could be accounted for by the fact that the MRI was done ten months after the accident, the panel is of the view that it is more likely that the tear occurred earlier and prior to the accident, particularly as the medical tests and reports at the time of injury did not point to an immediate or acute issue with respect to her PCL.

Based on the foregoing, the panel finds that the worker's June 7, 2016 workplace accident did not cause, aggravate or enhance the worker's PCL tear. The panel further finds that the worker's ongoing symptoms were not consistent with her previous symptoms or mechanism of injury, and her ongoing symptoms and difficulties are not related to her June 7, 2016 workplace accident.

In the result, the panel finds, on a balance of probabilities, that the worker did not sustain a further loss of earning capacity or require further medical aid as a result of her June 7, 2016 workplace accident. The panel therefore finds that the worker is not entitled to further benefits in relation to that accident.

The worker's appeal is dismissed.

Panel Members

M. L. Harrison, Presiding Officer
A. Finkel, Commissioner
M. Kernaghan, Commissioner

Recording Secretary, J. Lee

M. L. Harrison - Presiding Officer
(on behalf of the panel)

Signed at Winnipeg this 11th day of February, 2019