The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker appealed the Workers Compensation Board ("WCB") decision that their claim is not acceptable, and a hearing took place on March 4, 2025 to consider the worker's appeal. After the hearing, the appeal panel requested and received additional information, which it shared with the participants, before meeting on September 10, 2025 to discuss the case and render a decision.

Issue

Is the claim acceptable?

Decision

The claim is acceptable.

Background

The worker made a claim to the WCB on September 29, 2022 that they sustained injury to their hands, fingers, wrists and forearms at work on September 13, 2022. The worker attributed the injury to repetitive and intensive use of the keyboard and mouse while performing their job duties. The worker noted onset of symptoms in late July 2022 or early August 2022, when they sought medical treatment and were referred for a nerve conduction study, which happened on September 13, 2022, the last day they worked. The worker advised they had a prior diagnosis but with treatment, they had no difficulties since that time and their treatment providers ruled out that condition as the cause of their current difficulties.

A report from the treating physiatrist that included a copy of the nerve conduction study of September 13, 2022 indicated the worker had moderate median neuropathy, or carpal tunnel syndrome ("CTS") bilaterally, a flare of rheumatoid arthritis ("RA"), and tenosynovitis of the wrist flexors. The physiatrist noted the worker’s diagnosis some 5 years earlier of RA and the diagnosis some 3 years earlier of CTS. The physiatrist reported the worker’s RA was treated with medication that also provided relief for the CTS symptoms and as such, the worker did not proceed with the recommended carpal tunnel release surgery. The physiatrist outlined the worker's report that over the previous 2 weeks, they experienced significant pain in their hands and wrists, worse when performing repetitive tasks such as keyboarding and mousing, as well as forearm pain and some numbness evident at night and first thing in the morning. The physiatrist prescribed use of wrist braces when sleeping for 3 months, advised the worker of the benefits of a wrist injection and recommended surgery should conservative treatment not relieve their symptoms.

In a report arising out of an appointment on September 16, 2022, the treating family physician recorded the worker's report of bilateral wrist pain, difficulty working on a keyboard and mouse and noted the worker related their difficulties to repetitive movement on the computer while performing their job duties. The physician noted tenderness on the ulnar side and dorsum of both hands and highlighted that a recent nerve conduction study indicated bilateral CTS. The family physician referred the worker to a plastic surgeon for possible carpal tunnel release surgery and provided a medical note placing the worker off work from September 13, 2022 to September 23, 2022. A later note from the treating physician extended the worker's leave from work to October 23, 2022.

At a physiotherapy assessment on September 21, 2022, the worker reported bilateral forearm, wrist and hand pain and numbness while performing their job duties starting the week of July 25, 2022, noting the symptoms were initially mild and worsened over the course of a few weeks. The worker also reported numbness and tingling in both hands, first thing in the morning and pain in their forearms, aggravated by repetitive use of their hands. The treating physiotherapist recorded their findings and provided a diagnosis of bilateral CTS and wrist flexor tendinitis/tenosynovitis. The physiotherapist outlined work restrictions to be in place for 4 weeks.

The treating rheumatologist saw the worker on September 27, 2022 and recorded the worker's report of pain in their forearms after a lot of keyboard and mouse use, which caused them to stop working. The rheumatologist noted the previous diagnosis of RA, with onset in 2016 and worsening symptoms in the winter of 2019. MRI imaging revealed inflammatory arthropathy with synovitis in the worker’s left wrist and ultrasound testing found Doppler signal and joint effusion. On examination, the rheumatologist found no evidence of inflammatory arthritis in the upper limbs, noting the worker’s pain was localized to their volar forearm and opined the worker had no evidence of a flare in their RA.

The Employer’s Incident Report submitted to the WCB on October 6, 2022 outlined that the worker injured their left and right wrists and left and right hands at work on September 13, 2022. The employer advised that the worker contacted their supervisor the same day reporting they were seeking medical attention for CTS caused by their work and may require surgery.

When the WCB contacted the worker on October 12, 2022, the worker confirmed the information in their incident report and that they first noticed symptoms in late-July or early August 2022. The worker advised they began wearing wrist braces in July 2022 and described being unable to hit buttons with any strength, pain and tingling, loss of accuracy, severe pain in forearms, left hand a little better than the right, tingling and numbness into both thumbs and heel of hand, pinky and ring fingers and into other fingers as well and inflammation of tendons going to their forearms. The worker confirmed all their work involves using a mouse and keyboard and that they had started their employment fulltime in January 2022 on an employment contract ending October 7, 2022. The worker advised there was no change to their job duties after the 3-month training period, and that from the end of March 2022, they were doing their regular job duties full time. The worker confirmed they contacted their supervisor on September 13, 2022 to advise of their difficulties and had tried to contact them before that. The worker noted their last day worked was September 13, 2022 and stated they related their symptoms to their job duties as they did not have that pain before starting this employment.

On October 17, 2022, the WCB advised the worker that their claim was not accepted as it could not establish that the worker's job duties amounted to an accident that would cause development of CTS. The worker submitted additional medical information to the WCB in December 2022, including an October 26, 2022 report from their treating physiatrist, an October 31, 2022 letter from their treating physiotherapist, a November 10, 2022 letter from their treating rheumatologist and a December 9, 2022 letter from their treating endocrinologist, supporting the worker’s request for the WCB to reconsider their decision. The worker also submitted copies of research studies on risk factors and development of CTS. On December 28, 2022, the WCB advised the worker the additional information was reviewed and there would be no change to the decision the claim was not acceptable.

On January 10, 2023, the WCB received a January 6, 2023 report from the worker’s treating plastic surgeon indicating the worker reported a flare-up of their RA which aggravated CTS and resulted in the worker being off work. The surgeon recorded clinical test results and diagnosed moderate CTS, recommending a repeat nerve conduction study and that the worker consider carpal tunnel release surgery. In a chart note dated February 17, 2023, the surgeon again recorded positive test findings and set out that the worker wanted to go ahead with the proposed release surgery.

The WCB received a Physiotherapy Initial Report for an assessment on April 11, 2023. The physiotherapist noted the worker's description of a repetitive stress injury from repetitive keyboard and mouse use, and noted the worker's complaints of difficulty flexing their 4th and 5th fingers bilaterally with increased use, ulnar side forearm and 4th and 5th digit numbness and tingling, burning sensation after typing, palmar pain into 1st and 3rd fingers to fingertips with constant numbness and tingling, limited function to use the computer as symptoms increase and feelings of tightness, achiness and weakness in both extensor and flexors with inner elbow pain greater on the left side. The physiotherapist found mild palmar wasting of hand intrinsics bilaterally, ulnar and median nerve upper limb tension tightness sensitized at the wrist and elbow and positive testing for carpal tunnel bilaterally and medial epicondyle testing on the left. The physiotherapist offered a diagnosis of bilateral CTS and stated the worker was totally disabled from work. On April 12, 2023, the WCB advised the worker that upon review of the additional medical information, there was no change to the previous decisions.

On May 5, 2023, the worker submitted further information to the WCB, and on May 15, 2023, the WCB advised the worker the information was reviewed but the decision was unchanged.

On July 31, 2023, the worker requested Review Office reconsider the WCB's decision. On request of Review Office, the worker's file and the medical information were reviewed by a WCB plastic surgery consultant on September 14, 2023. The WCB consultant concluded the worker's diagnosis was bilateral CTS and noted that the risk factors for development of CTS involved a combination of force and repetition, or force and awkward positioning. The consultant noted there was insufficient evidence to relate keyboard activities as a risk factor and very strong evidence that certain comorbidities, including inflammatory arthritis such as rheumatoid, thyroid disease and diabetes, represented risk factors for CTS. In reviewing the information provided, the WCB plastic surgery consultant opined the worker's reported job duties did not require the threshold of grasp force associated with CTS. On reviewing a copy of the WCB plastic surgery consultant's opinion, the worker provided a submission in response on October 12, 2023. Review Office determined on October 18, 2023 that the worker's claim was not acceptable.

On May 23, 2024, the worker submitted additional information, including chart notes from a pain management clinic physician dated April 25, 2022, a February 15, 2024 report from a physician with an interest in occupational medicine, and a January 11, 2024 report from an ergonomist. The worker requested Review Office reconsider the earlier decision based on the new information provided. On June 4, 2024, Review Office again determined the worker's claim was not acceptable. The worker's representative appealed to the Appeal Commission on June 14, 2024 and a hearing was arranged.

Reasons

Applicable Legislation and Policy

The worker is employed by a federal government agency or department and therefore this claim is adjudicated under the Government Employees Compensation Act (the "GECA"). Section 4(1) of the GECA provides that an employee is entitled to compensation if they sustain personal injury by an accident arising out of and in the course of their employment. An accident is defined in s 2 of the GECA to include "a wilful and an intentional act, not being the act of the employee, and a fortuitous event occasioned by a physical or natural cause." Section 4(2)(a) of the GECA provides that a federal government employee in Manitoba receives compensation at the same rate and under the same conditions as a worker who is covered under The Workers Compensation Act (the "Act").

The Appeal Commission and its panels are bound by the provisions of The Workers Compensation Act (the “Act”), regulations under the Act and the policies established by the WCB's Board of Directors. The Act defines an accident, in s 1(1) as including a chance event occasioned by a physical or natural cause, a wilful and intentional act that is not the act of the worker, or an event or condition, or a combination of events or conditions, related to the worker's work or workplace, that results in personal injury to a worker, including an occupational disease, post-traumatic stress disorder or an acute reaction to a traumatic event. The Act provides in s 4(1) that compensation under the Act is payable to a worker who sustains personal injury by accident arising out of and in the course of the employment.

The WCB established Policy 44.05, Arising Out of and in the Course of Employment (the "Arising Policy") which confirms that an injured worker will be entitled to compensation under the Act if the WCB determines that they suffered a personal injury by accident and that the accident arose out of and in the course of employment and provides how the WCB determines whether an accident arose out of and in the course of employment.

The WCB established Policy 44.10.20.10, Pre-existing Conditions (the "Pre-existing Policy"), to address eligibility for compensation in circumstances where a worker has a pre-existing condition, which the Policy defines as any medical condition the worker had prior to their workplace injury. The Policy outlines that a pre-existing condition may contribute to the severity of a workplace injury or significantly prolong a worker's recovery, and workplace injuries can impact pre-existing conditions. A temporary worsening of a worker’s pre-existing condition is considered an aggravation of the pre-existing condition and a permanent worsening of the worker’s condition because of a workplace injury is an enhancement of the pre-existing condition.

Worker's Position

The worker's position, as outlined by the worker advisor in their written and oral submissions, is that the evidence supports a finding that the worker sustained bilateral arm injuries as a result of undertaking their job duties in an environment that was ergonomically deficient and required intense and sustained repetitive motions with their hands, wrists and arms and therefore the claim should be accepted. Alternatively, the worker's position is that these same job duties caused or contributed to an increase in symptoms of the worker's pre-existing conditions, resulting in the aggravation or enhancement of the pre-existing conditions, and as such the claim should be accepted.

Employer's Position

The employer did not participate in the appeal.

Analysis

The worker's appeal arises out of the WCB's decision that the worker's claim is not acceptable. For the appeal to succeed, the panel would have to find that the worker sustained injury as a result of an accident arising out of and in the course of their employment. As detailed below, the panel was able to make such a finding and therefore the worker's appeal is granted.

The panel considered that the definition of accident under the GECA includes "a fortuitous event occasioned by a physical or natural cause" and that an employee is entitled to compensation under that legislation if they sustain personal injury by an accident arising out of and in the course of their employment. The GECA also provides that a federal employee working in Manitoba is entitled to compensation under the same conditions as a worker covered by the Act.

The panel considered whether the evidence supports a finding that this worker was injured by an accident arising out of and in the course of their employment. The worker's accident report indicates they sustained injury to both arms while undertaking their usual job duties, involving use of a computer with keyboard and mouse while working from a home office with poor ergonomic setup, with symptom onset first noted during the summer of 2022, and that by September 13, 2022, they were unable to continue working.

The evidence before the panel supports a finding that the worker's symptoms arose in the course of their employment, which they began in January 2022 followed by a three-month training period. The medical reporting confirms that in late April 2022, the worker already reported some pain in their hands and wrists and that by early August 2022, the worker sought medical attention in relation to numbness and tingling in their hands, which they attributed to repetitive motion in their job. Furthermore, the evidence from the worker's medical treatment providers indicates that prior to starting their employment in January 2022, the medication prescribed to treat the worker's RA was successful in that there were no flareups of the inflammatory arthritis noted and there was a related improvement in the worker's CTS symptoms. The panel also noted there is no evidence to indicate the worker's report of any increase in hand and wrist symptoms until April 2022, more than three months after the worker's employment began and after the period of training had ended.

The panel reviewed the medical reporting and noted the worker was previously diagnosed with bilateral rheumatoid arthritis, with a "likely onset in 2016, with worsening symptoms in the winter of 2019." The worker was also diagnosed with left CTS, a complete tear of the left scapholunate ligament and the triangular fibrocartilage disc, as well as synovitis of the flexor and extensor tendons in 2019. As well, there are findings from a December 2019 nerve conduction study that indicate bilateral median neuropathies at the wrists. We find that these conditions, diagnosed well before the worker even began this employment, are pre-existing conditions. Further, we note that these are the active diagnoses referenced in the medical reporting leading up to and following the worker's medically mandated removal from work duties in September 2022, and as such, we are satisfied that there is evidence that these diagnoses or conditions did not arise out of the worker's employment.

The panel also considered whether there is evidence that the worker's job duties would not have impacted any of the pre-existing conditions, whether as an aggravation or enhancement, as defined in the Pre-Existing Policy. We noted the treating family physician reported in August 2022 that the worker's RA seemed "symptomatically under control" and in September 2022 that there was "No evidence of a flare of [the] rheumatoid arthritis at this time" but the treating physiatrist outlined in a September 13, 2022 report their impression that the current diagnoses were of bilateral moderate CTS, probable polyneuropathy and "Rheumatoid arthritis flare with tenosynovitis of wrist flexors." The panel also reviewed the February 15, 2024 report from the physician with an interest in occupational medicine, who concluded that the "worker's job duties resulted in the reactivation" of their bilateral CTS. Based on these comments and noting the absence of any WCB opinion as to whether the worker's job duties impacted the pre-existing arm conditions, the panel obtained an opinion from a WCB Physical Medicine and Rehabilitation Consultant dated June 17, 2025. The consultant concluded:

"In my opinion, [the worker's] reported keyboard and mouse utilization while in the performance of [their] job duties, the repetitive key strokes for commends, cutting and pasting documents over 7.5 hours per day, 5 day work week, and the probable contribution from suboptimal work station ergonomics could have impacted [their] pre-existing arm conditions.

While progress in [the worker's] pre-existing arm conditions could have occurred without a work related contribution over the period January 2022 ([their] start of employment) to September 2022 (going off work), it is probable that the aforementioned job demands temporarily aggravated the pre-existing arm conditions (over the duration of [their] employment).

With no material evidence that enhancement occurred of the pre-existing arm conditions over [the worker's] period of employment within the aforementioned job demands."

Noting the consultant's areas of expertise and that they reviewed the worker's claim file in its entirety including the latest medical reporting available and the transcript of this appeal hearing, the panel gives significant weight to the consultant's opinion that the worker's pre-existing arm conditions were impacted by their job duties during their period of employment. As the panel did not specifically request or require an opinion as to whether this amounted to an aggravation or an enhancement of those conditions and as the WCB has not adjudicated that question, we make no findings in that respect.

Based on the evidence before the panel, we are satisfied that as a result of the combined effects of the worker's job duties and the identified ergonomic deficiencies in their work station as detailed in the file evidence, the worker experienced an increase in the symptomatic presentation of their pre-existing bilateral arm conditions which amounts to an injury caused by an accident arising out of and in the course of their employment.

Based on the evidence before the panel and on the standard of a balance of probabilities, we are satisfied that the worker sustained injury as a result of an accident arising out of and in the course of their employment. Therefore, the claim is acceptable, and the appeal is granted.

Panel Members

K. Dyck, Presiding Officer
J. Peterson, Commissioner
M. Kernaghan, Commissioner

Recording Secretary, J. Lee

K. Dyck - Presiding Officer
(on behalf of the panel)

Signed at Winnipeg this 18th day of September, 2025