The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker is appealing the decision made by the Workers Compensation Board ("WCB") that responsibility should not be accepted for the worker's right total knee replacement. A videoconference hearing was held on March 2, 2022 to consider the worker's appeal.

Issue

Whether or not responsibility should be accepted for the worker's right total knee replacement as being a consequence of the March 29, 2019 accident.

Decision

That responsibility should not be accepted for the worker's right total knee replacement as being a consequence of the March 29, 2019 accident.

Background

On April 1, 2019, the worker filed a Worker Incident Report with the WCB, reporting an injury to her lower back/right knee that occurred at work on March 29, 2019. The worker reported she slipped on ice and twisted her right knee, noting that in the process "…I felt a shooting and throbbing pain in my knee. I did not finish my shift. The next day, I felt sharp pain in my lower back." The worker sought medical attention at a local hospital emergency department the same day, reporting her slip and fall and having twisted of her right knee. On examination, it was noted that there was no laxity, swelling or bruising on her right knee, but there was tenderness to her proximal tibia. The diagnosis of a mild knee strain was provided, and it was recommended that the worker use crutches for a couple of days and that modified duties might be required at work.

At an initial physiotherapy assessment on April 4, 2019, the worker was diagnosed with a right knee meniscus sprain and low back sprain. The physiotherapist noted the worker was complaining of severe right knee joint pain, popping or clicking on the inside of her right knee joint, and increased pain with standing, walking and climbing stairs. Grade 1 tenderness and mild swelling was noted along the worker's right knee joint.

The worker also was seen by her family physician on April 4, 2019. The worker reported to her physician that she slipped on ice at work on March 29, 2019, grabbed on to a portion of a fence as she fell, and immediately developed right knee pain. The worker also reported that currently her right knee was locking and popping, and she had increased pain with weight-bearing and flexion. The worker further reported that the following day, she noticed low back pain with movement, that radiated laterally to her right hip. After examining the worker, the treating physician noted decreased range of motion in the worker's spine, with tenderness, and pain with flexion, decreased range of motion, and swelling medially in her right knee. The physician diagnosed the worker with a right knee sprain, and queried an aggravation of a medial meniscal or medial collateral ligament tear in the right knee, and a lower back strain. The physician recommended the worker remain off work until April 12, 2019, then return to work on modified duties.

At a follow-up appointment with the family physician on April 15, 2019, the physician noted that the worker had continued difficulty with weight-bearing and her right knee locking, but her lower back and right hip pain were resolved, and the worker's treating family physician referred the worker for an MRI of her knee.

The WCB contacted the worker on April 18, 2019 to discuss the claim. The worker confirmed the mechanism of injury and advised she had not had trouble with her knee before. The worker reported her knee felt worse at the back, with swelling when sitting. After discussion with the employer, the worker returned to work on modified duties and reduced hours on May 23, 2019.

On June 13, 2019, the worker underwent an MRI on her right knee, which showed:

1. Osteoarthritis, moderate in the medial and patellofemoral compartments and mild in the lateral compartment. 

2. Vertical tear anterior horn lateral meniscus.

The worker was seen by her family physician on June 24, 2019 to review the MRI, and the physician requested that the worker be assessed by an orthopedic surgeon. On July 9, 2019, the worker was seen by the orthopedic surgeon. After examining the worker, the surgeon opined that the majority of the worker's pain in her knee came from the lateral meniscus tear, as most of the worker's symptoms were over the lateral joint line. The orthopedic surgeon noted, however, that "In the areas of greater osteoarthritis including medially she has less symptoms." The orthopedic surgeon recommended arthroscopic surgery, with a view to partial lateral meniscectomy. The surgeon noted the worker was made aware that surgery "…will have no impact over the degenerative changes in the knee and is also aware that these conditions were likely pre-existing." The surgeon further indicated that if the arthroscopy was not successful and the worker continued to have symptoms after the tear was debrided, they might need to consider knee replacement surgery.

On July 26, 2019, the worker's file was reviewed by a WCB sports medicine consultant, who opined that a lateral meniscus tear would be medically accounted for by a twisting injury, similar to the mechanism of injury the worker reported. The consultant noted that the degenerative changes found at the medial and patellofemoral compartments were not medically accounted for by the workplace accident but related to a pre-existing condition. The WCB sports medicine consultant further opined that if the lateral meniscus tear was considered to be acceptable by the WCB, the surgery would be authorized, with an expected recovery time of six to eight weeks. It was also noted that the worker's pre-existing condition was not anticipated to delay recovery.

On August 1, 2019, the WCB sports medicine consultant advised the orthopedic surgeon that the proposed procedure for right knee arthroscopy and partial medial lateral meniscectomy were authorized, but responsibility was not accepted for any treatment to the MRI-noted tricompartmental osteoarthritic changes. On September 9, 2019, the worker underwent right knee arthroscopy, partial lateral meniscectomy, partial medial meniscectomy, chondroplasty medial compartment, chondroplasty patellofemoral joint and partial synovectomy.

The WCB contacted the worker on September 12, 2019, and again on October 7, 2019, to discuss her recovery from the surgery, along with possible timelines for a graduated return to work. On October 7, 2019, the worker advised that she was still in a lot of pain, and that at an appointment with the treating orthopedic surgeon on October 3, 2019, the surgeon noted concern at the swelling in her right knee. The worker further advised she was attending an initial physiotherapy session the following day.

At the initial physiotherapy assessment on October 8, 2019, the worker's physiotherapist indicated the worker had tenderness, swelling and stiffness, and reported feeling instability with clicking and locking while walking. The physiotherapist recommended rest and that the worker remain off work for four weeks.

On November 4, 2019, the worker contacted the WCB to provide a further update. The worker reported that she had seen the orthopedic surgeon on October 31, 2019 and he had scheduled a second surgery for November 25, 2019 as he was concerned about complication from the first surgery and her lack of improvement. The November 25, 2019 surgical report indicated the worker underwent a second right knee arthroscopy, chondroplasty lateral compartment, and chondroplasty patellofemoral joint, with manipulation of the knee.

At a follow-up appointment on December 30, 2019, the treating orthopedic surgeon noted the worker continued to have significant swelling of her knee of unknown cause. The surgeon indicated that a knee replacement should not be considered at that time, but the worker would require more extensive rehabilitation and should continue with physiotherapy. The surgeon suggested that a return to work around mid-February might be reasonable.

On February 18, 2020, the worker attended a follow-up appointment with her treating orthopedic surgeon. The surgeon noted the worker's report of ongoing pain and swelling, and on examination, found decreased range of motion but a near normal exam after Lachman, Anterior Drawer and Pivot Shift testing. The surgeon did not recommend further surgical intervention, but recommended continued physiotherapy and a functional assessment to set out specific restrictions for a return to work.

On March 5, 2020, the worker attended a call-in examination with a WCB orthopedic consultant, who provided an opinion to the worker's file on March 9, 2020. The consultant opined that the worker's initial diagnosis in relation to the March 29, 2019 workplace accident was a right lateral meniscal tear, and her current diagnosis also included post-operative arthrofibrosis involving the post-operative right knee. The WCB orthopedic consultant opined that given the worker did not feel safe driving and mobilized with the use of a tripod-type cane, she would be unable to perform her job duties and would not be capable of even sedentary duties.

Due to ongoing issues, the treating orthopedic surgeon recommended a further MRI for the worker's knee. The MRI was performed on April 8, 2020, and indicated:

1. Tricompartmental degenerative change essentially unchanged. 

2. Mild degenerative change medial meniscus without complicating tear. 

3. Mild truncation anterior horn lateral meniscus with no evidence for residual or recurrent meniscal tear.

The MRI report and the worker's file were reviewed by the WCB orthopedic consultant on April 20, 2020. The consultant opined that the worker continued to experience right knee pain, as well as persistent swelling, with a restricted range of motion. The WCB orthopedic consultant opined that the worker still appeared to be restricted in the use of her right knee and recommended restrictions of a standing and walking tolerance of approximately 30 minutes; no squatting, crouching, crawling, or ladder climbing; and level terrain with a load carrying limit of 20 pounds for a short distance. The restrictions were provided to the employer on April 22, 2020.

The worker returned to work on a graduated basis on May 1, 2020. A four week strengthening program was recommended and approved for the worker, with the initial assessment taking place on May 7, 2020. The worker continued to work modified duties on a graduated basis, and as there was improved pain control and function with the strengthening program, the sessions were continued for a further four weeks.

On June 16, 2020, the worker was seen by the treating orthopedic surgeon for a further follow-up. The surgeon noted the worker's ongoing pain and need for the use of cane to ambulate, and recommended sedentary duties only for work, with modified hours. The surgeon opined that consideration was to be given to a total knee replacement due to the worker's ongoing symptoms. On August 12, 2020, the worker contacted the WCB to advise that she had seen the orthopedic surgeon the previous day and he had placed her on a waiting list for knee replacement surgery.

On August 25, 2020, the WCB orthopedic consultant again reviewed the worker's file. The consultant summarized the medical treatment received by the worker and noted the worker's poor recovery from both surgeries, with continued pain, swelling and reduced range of motion in her knee. The consultant opined that ongoing restrictions remained appropriate, including restricted standing and walking of 30 minutes or less, and avoiding squatting, crouching, and climbing. The consultant further noted the treating orthopedic surgeon's hesitation to consider a total knee replacement, as well as the pre-existing degenerative conditions within the worker's knee.

A November 10, 2020 report was received by the WCB from the treating orthopedic surgeon recommending total knee replacement surgery. The surgeon noted that despite ongoing therapy and time, the worker's knee had not responded to treatment, and after long consideration and discussion, they had decided to proceed with the surgery. In a memorandum to file dated November 24, 2020, the WCB's orthopedic consultant recommended against approving coverage of the proposed total knee replacement surgery, indicating that such surgery was "…necessitated by virtue of preexisting advanced arthritis." On December 8, 2020, the WCB advised the worker that they would not be accepting responsibility for the proposed total knee replacement surgery as it had been determined that surgery was required as a result of pre-existing degenerative conditions.

On December 23, 2020, the treating orthopedic surgeon provided a letter to the WCB opining that the March 29, 2019 workplace injury was "…at the very least a major exacerbating factor to the deterioration of the joint." The surgeon further opined that while some degree of osteoarthritis is quite common, "it is very unlikely that [the worker] would be in her current predicament if the injury had not occurred." On January 12, 2021, the WCB advised the worker that the information from the treating orthopedic surgeon had been reviewed but there would be no change to the December 8, 2020 decision.

On February 9, 2021, the worker requested that Review Office reconsider the WCB's decision. The worker set out a chronology of her injury and noted she continued to experience difficulties with her knee that were restricting her ability to work as much as she did before her injury or to perform her regular duties.

On April 6, 2021, Review Office determined that responsibility should not be accepted for the worker's right total knee replacement. Review Office found that the medical evidence on the worker's file supported the worker's pre-existing degenerative conditions in her knee were present before the March 29, 2019 workplace accident, and that the evidence did not support that the pre-existing degenerative conditions were enhanced or aggravated by the workplace accident. Review Office further noted it was "unlikely and unusual" for a worker to require a total knee replacement in such close proximity to the workplace accident if the accident was a factor.

On September 24, 2021, the worker's representative appealed the Review Office decision to the Appeal Commission and a videoconference hearing was arranged.

Reasons

Applicable Legislation and Policy

The Appeal Commission and its panels are bound by The Workers Compensation Act (the "Act"), regulations made under the Act 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.

Subsection 27(1) of the Act states 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 27(10) states, in part, that "Medical aid furnished or provided under any of the preceding subsections of this section shall at all times be subject to the supervision and control of the board..."

The WCB's Board of Directors has established WCB Policy 44.10.20.10, Pre-existing Conditions (the "Policy"), which addresses eligibility for compensation in circumstances where a worker has a pre-existing condition. The purpose of the Policy is stated, in part, as follows:

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.

Worker's Position

The worker was represented by a worker advisor, 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 representative, and the worker and her representative responded to questions from the panel.

The worker's position was that the March 29, 2019 workplace accident and the worker's lack of recovery from that accident resulted in the need for the right total knee replacement, and the WCB is responsible for that procedure and associated benefits.

The worker's representative submitted that the evidence shows the worker had no knee issues or problems prior to the day of the accident. On the day of the accident, she slipped on the ice, caught herself on the fence, and twisted her knee. Her claim was accepted, with the accepted diagnosis being a right knee sprain, that was later changed to a right lateral meniscus tear after imaging.

The worker's representative reviewed the history of the worker's injury and treatment, with reference to various reports on file. The representative also referred to a letter of support from the treating orthopedic surgeon dated July 22, 2021, which had been provided in advance of the hearing. The representative quoted from the July 22, 2021 letter, noting that the surgeon indicated the diagnoses that were relevant to the knee were "severe right knee pain related to underlying osteoarthritis and possible associated chronic regional pain syndrome following knee arthroscopy" and that the worker's "level of pain and disability has been significant and in excess of what would have been expected given the underlying pathology. She has not responded to conservative management and sufficient time to rehabilitate. Options have been discussed and she wishes to proceed with TKA [total knee arthroplasty]."

The worker's representative further noted that the surgeon stated in his July 22, 2021 letter that "although impossible to prove definitively, it has been my experience that these injuries often accelerate and aggravate symptoms of osteoarthritis in patients, even those who are relatively asymptomatic prior to the injury..." and that the worker's "…arthroscopic procedure certainly did not improve matters, and unfortunately may have indeed further aggravated the knee and symptoms from her degenerative changes."

The worker's representative submitted that what is important in this case is the continuity in symptoms since the date of the accident. The worker had no symptoms prior to the accident. Since the accident, she has been in constant pain and her knee has been constantly swollen and inflamed. The representative submitted that it is this swelling and pain, combined with the worker's inability to weight-bear without aids, that led to the need for the total knee replacement.

The worker's representative submitted that it is a well-known medical fact that surgeries and severe inflammation can accelerate arthritis in joints. The representative submitted that the worker's extreme inflammatory response to the surgeries and the accident was not factored into the WCB medical opinion, nor was the new diagnosis of chronic regional pain syndrome ("CRPS") from the second surgery factored into that opinion. The representative submitted that the WCB is responsible for both of these issues as they were caused by the accident or by the WCB-funded treatment for the accident.

In conclusion, it was submitted that "but for" the March 29, 2019 workplace accident, there may never have been a need for a total knee replacement. The accident, combined with the pre-existing condition, the subsequent severe inflammatory response to the injury and the surgeries, and the CRPS that resulted from the WCB-funded surgery, resulted in the need for a total knee replacement at the time it did, and the worker's appeal should be allowed.

Employer's Position

The employer did not participate in the appeal.

Analysis

The issue before the panel is whether or not responsibility should be accepted for the worker's right total knee replacement as being a consequence of the March 29, 2019 accident. For the worker's appeal to be successful, the panel must find, on a balance of probabilities, that the right total knee replacement is necessary to cure and provide relief from the worker's injury resulting from the March 29, 2019 workplace accident. The panel is unable to make that finding, for the reasons that follow.

The worker's representative has argued that a combination of various factors contributed to the worker's need for a right total knee replacement.

The worker described the mechanism of injury at the hearing. Based on the evidence on file, and as presented at the hearing, the panel is satisfied that the workplace accident itself appeared to be relatively minor in nature. The worker's claim was accepted for a right knee strain, but this was a later changed to a lateral meniscus tear, and the WCB authorized surgery, consisting of arthroscopy and meniscectomy or meniscal repair, which was performed on September 9, 2019.

With respect to the surgical procedures that were authorized and performed, the panel places weight on the August 25, 2020 opinion of the WCB orthopedic consultant that "An anterior horn lateral meniscal tear with partial, not total menisectomy (sic), is not that which is likely to lead to consideration of replacement in such a short time."

With respect to the effect of pre-existing conditions, the panel acknowledges the worker's evidence that she did not have problems with her right knee and was relatively asymptomatic prior to the accident. The panel finds, however, that the evidence indicates the worker had fairly significant pre-existing degenerative conditions in her right knee prior to the March 29, 2019 workplace accident which were not related to her workplace injury.

In this regard, the panel places weight on the July 26, 2019 opinion of the WCB sports medicine consultant, who noted that in addition to the lateral meniscus tear:

There is also evidence of degenerative changes at the medial and patellofemoral compartments being currently symptomatic (medial joint line tenderness), however these would not be medically accounted for by the workplace injury. Rather, these relate to a pre-x condition.

The panel also places weight on the April 17, 2020 opinion of the WCB orthopedic consultant, who opined that:

On a pre-existing basis (to the CI [compensable injury] March 29, 2019), there is evidence of medial compartment and patellofemoral wear (chondromalacia).

Indeed the latest MRI report describes "tricompartmental degenerative change essentially unchanged".

Unchanged that is from the MRI of June 13, 2019.

That MRI performed but two and one half months after the CI.

The panel is further unable to find that the evidence supports the worker's pre-existing degenerative conditions or changes were enhanced by the workplace accident or surgeries. The panel notes that in a November 4, 2020 opinion, the WCB orthopedic consultant opined that the facts of the case and time frame did not "allow for any credible consideration of acceleration or enhancement of the pre-existing arthritic process."

In addition, while the worker's representative relied at the hearing on the July 22, 2021 letter from the treating orthopedic surgeon, the panel notes that in his response to a question from the worker's representative as to whether the surgeries or the complications aggravated, enhanced or accelerated the course of the worker's pre-existing condition, the surgeon only indicated that the arthroscopic procedure "certainly did not improve matters" and "may have" further aggravated the knee and symptoms from her degenerative changes.

While the worker's representative also referred to WCB-funded surgeries, the panel notes that the WCB accepted responsibility for part only of the surgeries which were performed, and did not accept responsibility for surgical procedures that were directed to the worker's pre-existing degenerative conditions. The panel is unable to find that the available evidence supports that the surgical procedures which were approved by the WCB and performed were a factor in terms of the need for a total knee replacement.

The panel also notes that the treating orthopedic surgeon had acknowledged in his report dated December 30, 2019 that the worker's "ongoing symptoms in the knee are somewhat of a mystery."

While the worker's representative further referred in her submission to CRPS "…that resulted from the WCB-funded surgery", suggesting that this was one of the combined causes which led to the need for a right total knee replacement, the panel is unable to find that there is any such diagnosis on file. The panel acknowledges that the treating orthopedic surgeon referred in his July 22, 2021 letter to "possible" associated CRPS following knee arthroscopy, and the worker stated at the hearing that the last time she saw her doctor he told her she had CRPS, but finds that there is a lack of evidence on file to support such a diagnosis. Further, or in any event, the panel is satisfied that a relationship between any such diagnosis and the need for a total knee replacement is not supported by the evidence which is before us.

Based on the foregoing, the panel finds, on a balance of probabilities, that the right total knee replacement is not necessary to cure or provide relief from the worker's injury resulting from the March 29, 2019 workplace accident. The panel therefore finds that responsibility should not be accepted for the worker's right total knee replacement as being a consequence of the March 29, 2019 accident.

The worker's appeal is dismissed.

Panel Members

M. L. Harrison, Presiding Officer
J. Peterson, Commissioner
M. Payette, Commissioner

Recording Secretary, J. Lee

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

Signed at Winnipeg this 29th day of April, 2022