The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker appealed the Workers Compensation Board ("WCB") decision that their claim is not acceptable. A panel considered the worker's appeal at a hearing held on August 19, 2026.

Issue

Is the claim acceptable?

Decision

The claim is not acceptable.

Background

The employer submitted an Employer’s Accident Report to the WCB on September 19, 2025 describing an injury to the worker’s left and right wrists that occurred on March 24, 2025 and was reported to the employer on September 18, 2025. The employer noted the worker advised they were diagnosed with carpal tunnel syndrome ("CTS") bilaterally and may require surgery. The employer noted it provided a dictation system for the worker's use to limit repetitive stress on the worker’s wrists. On September 24, 2025, the employer also provided a copy of the worker’s job description to the WCB.

On September 24, 2025, the worker submitted a Worker Incident Report to the WCB noting they were diagnosed with severe carpal tunnel on their left wrist and moderate carpal tunnel on their right wrist on March 17, 2025. The worker attributed their development of CTS to their job duties during the COVID-19 pandemic which involved using fine hand movements during increased working hours. The worker reported first noticing symptoms in 2021, when their hands went numb with any fine motor movements. The symptoms progressed to the point where the worker wore wrist braces when they slept. Current symptoms include their hands going numb when driving, writing or using their hands or wrists. The worker noted they mentioned their difficulties to their co-workers periodically.

When the WCB spoke with the worker on October 3, 2025, the worker confirmed the information in their report, noting no time missed from work and that they continued working regular duties. The worker confirmed they underwent nerve conduction studies ("NCS") on March 17, 2025 and were diagnosed with CTS. The worker stated they were advised to avoid typing and computer work. The worker noted the employer offered a dictation program to help with their duties involving typing. The worker described current symptoms of throbbing hands on waking and numbness when driving, writing or performing fine motor tasks with their wrists.

The WCB received a copy of the March 17, 2025 report from the treating neurologist to the treating nurse practitioner which recorded the worker’s report of a history of “…left greater than right whole hand dysesthesia…” approximately 11 years ago, which worsened after increased computer work but also with driving or any use of their hands. The neurologist provided the NCS tests indicated "Moderate right median mononeuropathy at the wrist (as seen in carpal tunnel syndrome)" and "Mild left median mononeuropathy at the wrist." The neurologist recommended the use of carpal tunnel braces for night and voice-to-text software to reduce the worker's typing/mousing on their computer.

The WCB also received chart notes from the treating nurse practitioner for August 15, 2024 and October 16, 2025. The notes of August 15, 2024 indicated the worker was seen for concerns related to carpal tunnel, which the worker had a long history of, with symptoms causing sleep disturbance. The nurse practitioner recorded positive Tinel’s and Phalen's testing bilaterally as well as a ganglion at the right wrist and referred the worker for nerve conduction studies. The October 16, 2025 chart notes recorded the worker’s complaint of worsening CTS symptoms after undertaking specific tasks repetitively during the COVID-19 pandemic, and that the worker requested a referral for surgery after trialing conservative treatment involving bracing with no improvement. The chart notes included a copy of the referral to a plastic surgeon of October 17, 2025.

A WCB plastic surgery consultant reviewed the worker's file on November 19, 2025. They confirmed the medical information on file indicated the worker had bilateral CTS and a palmar wrist ganglion. The consultant noted that CTS typically develops over the long-term and that medical guidelines for the risk of development of CTS include work duties involving a combination of force and repetition or force and awkward posture, as defined in those guidelines. The consultant further noted the cause of the development of a ganglion is unknown. The WCB consultant outlined that conservative management of CTS symptoms includes nighttime splinting and that some patients require carpal tunnel release surgery.

On December 5, 2025, the WCB advised the worker by letter that the claim was not accepted as it could not establish a relationship between their job duties and their bilateral wrist difficulties.

On December 12, 2025, the worker requested Review Office reconsider the WCB’s decision, outlining their belief that the medical reporting indicated a relationship between their development of CTS and their job duties. On January 15, 2026, Review Office upheld the WCB’s decision that the claim was not acceptable.

The Appeal Commission received the worker's appeal on May 5, 2026 and arranged a hearing.

Reasons

Applicable Legislation and Policy

The Appeal Commission and its panels are bound by the provisions of The Workers Compensation Act (the "Act"), regulations under that Act and the policies established by the WCB's Board of Directors.

The Act defines an accident in s 1(1) as including:

(a) a chance event occasioned by a physical or natural cause, 

(b) a wilful and intentional act that is not the act of the worker, or 

(c) 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.

Under s 4(1) of the Act, a worker injured as a result of an accident at work is entitled to benefits. The WCB established Policy 44.10.20.10, Pre-Existing Conditions (the “Policy”) which provides that “The fact that the worker has a pre-existing condition does not disentitle them to compensation for their workplace injury. However, the workers compensation system is designed to compensate workers for workplace injuries, not all injuries. It is often necessary, therefore, to distinguish between a worker's pre-existing condition and their workplace injuries.” The Policy defines pre-existing condition as:

"…any medical condition the worker had prior to their workplace injury. Pre-existing conditions may contribute to the severity of a workplace injury or significantly prolong a worker's recovery. Workplace injuries can also have an effect on pre-existing conditions. When a worker’s pre-existing condition is temporarily worsened because of a workplace injury, this is considered an aggravation of a pre-existing condition. When a worker’s condition is permanently worsened because of a workplace injury, this is considered an enhancement of the pre-existing condition."

Worker’s Position

The worker appeared in the hearing on their own behalf, offering testimony in response to questions from members of the appeal panel, and relying upon a written submission provided to the Appeal Commission on July 17, 2026.

The worker's position is that the changes in their job duties during the COVID-19 pandemic caused the development of bilateral CTS. The worker described those job duties as involving repetitious and frequent use of both hands in undertaking fine motor activities, over the course of long shifts during that period. The worker confirmed they did not miss any work as a result, and resumed their regular job duties at some point prior to August 2024, but that their symptoms did not resolve and worsened to the point where they sought medical attention. The worker indicated they reported the injury to the employer in March 2025.

The worker described waking with numbness in both wrists and self-treating those symptoms with bilateral wrist braces, worn while sleeping. The worker noted experiencing similar symptoms some 14 years earlier but that those symptoms were completely resolved without treatment and confirmed they did not seek medical attention at that time.

When the symptoms were not resolved after the pandemic job duties concluded, the worker sought medical attention from their treating nurse practitioner on August 15, 2024 and obtained a referral for NCS. That testing occurred in March 2025 and indicated bilateral CTS, worse on the left than the right. The worker stated the treating physiatrist recommended surgery, but the worker confirmed they cancelled the surgical consult requested by the treating nurse practitioner pending the outcome of their WCB claim. The worker confirmed their belief they will require surgical treatment.

Employer’s Position

The employer was represented in the hearing by an advocate who made an oral submission on behalf of the employer. The employer’s position is that the worker’s claim should not be accepted as the evidence does not support a finding that the worker’s bilateral CTS arose out of the performance of their job duties in 2025, noting the worker reported onset of symptoms in 2020 that worsened with non-occupational activities. As such, the evidence does not establish an occupational cause for the worker's diagnosis. Further, the employer's representative noted that the diagnosis of bilateral CTS is not suggestive of an occupationally related cause. The employer's representative also noted the evidence that the worker experienced CTS symptoms previously, suggesting a pre-existing condition, and noted the absence of any evidence that the pre-existing condition was aggravated or enhanced by the worker's job duties.

Analysis

The issue for the panel to determine is whether the worker’s claim is acceptable. For the worker’s appeal to succeed, the panel would have to determine on the standard of a balance of probabilities that the worker was injured as a result of an accident as defined by the Act, arising out of and in the course of their employment. In other words, for the claim to be accepted, we must find that it is more likely than not that the worker sustained an injury caused by an event or condition, or a combination of events or conditions, related to their work or workplace. The panel was unable to make such a finding for the reasons detailed below and therefore determined the worker’s claim is not acceptable.

The worker’s claim arose out of the diagnosis of bilateral CTS in March 2025, which the worker believes developed due to the changes in their job duties beginning in 2020. The panel accepts and relies upon the medical evidence confirming this diagnosis, as supported by the diagnostic testing in March 2025. We note that the diagnosis of "Moderate right median mononeuropathy at the wrist (as seen in [CTS])" and of mid left median mononeuropathy at the wrist, described as bilateral CTS. The WCB plastic surgery consultant confirmed the diagnosis of "bilateral carpal tunnel syndrome" and noted the presence of a left palmar wrist ganglion.

In considering whether the worker's CTS can be causally related to the worker's participation in their employment activities, the panel reviewed the available medical opinions and reports. We noted the treating physiatrist outlined the worker's history of "left greater than right whole hand dysesthesias" during a pregnancy approximately 11 years earlier, described as "…progressively worsening with increasing computer work at [their] job but also with driving, painting, decorating cakes and anytime [the worker] is using [their] hands." The physiatrist outlined that the worker reported symptoms while sleeping and on waking, as well as flares of symptoms that also impact the left palmer ganglion cyst. The physiatrist recommended the worker avoid positions of excessive wrist flexion/extension, take frequent breaks when symptomatic, reduce typing and mousing with use of voice-to-text software and wear the nighttime braces every night. Further, the physiatrist recommended consideration of a carpal tunnel corticosteroid injection if the worker's symptoms flared again. The panel noted the specialist's recommendations for symptomatic relief or reduction with specific workplace accommodations and at-home treatment, but they did not comment on the cause of the worker's bilateral condition.

The panel also reviewed the treating nurse practitioner's chart, which documents the worker's statement that their symptoms arose when they took on pandemic-related job duties and progressive numbness and tingling to the point where the symptoms interfered with some job duties as well as driving and home activities. The chart note of August 15, 2024 references the worker's concerns related to carpal tunnel, with a "Long history of same" and no improvement with use of braces.

The panel also reviewed the WCB’s plastic surgery consultant's opinion of November 19, 2025, which indicates they consulted the AMA Guides to the Evaluation of Disease and Injury Causation (2014), an evidence-based review of the medical literature regarding a variety of conditions, including CTS and that the AMA Guides conclude, with respect to CTS:

• That there is very strong evidence that work duties involving a combination of i) force and repetition or ii) force and posture represent risk factors for CTS…. 

• That highly repetitive work alone had “conflicting (insufficient) evidence” to categorize such duties as a risk factor for CTS; 

• That awkward postures alone were considered low risk; and, 

• That there is insufficient evidence to relate keyboard activities as a risk factor for CTS.

The WCB consultant further outlined that the AMA Guides indicate that many of the reviewed studies on CTS define high force, high repetition and awkward posture as follows:

• High force was defined as more than 4 kilograms of force (per hand); 

• High repetitions was defined as a cycle time of less than 30 seconds or alternatively, more than 50% of the cycle time involved in performing fundamentally the same activity; and 

• Awkward posture was defined as more than 45 degrees of wrist flexion or extension without excessive radial or ulnar deviation.

The panel accepts and relies upon this evidence as a scientific basis upon which to establish an occupational cause for the development of CTS. We therefore considered these parameters in relation to the worker’s job duties as described by the worker in the hearing and as provided to the WCB. The panel noted the evidence that the worker is right hand dominant and that they experienced bilateral symptoms which are worse on the left than the right. We also noted the specific pandemic-related job duties described by the worker required use of both hands but in different ways, involving repetitively picking up and gripping small items hundreds of times over the course of a long shift, during certain periods of time. Considering the totality of the evidence, the panel is not satisfied that these job duties involve the required combination of repetitious and forceful gripping, or forceful gripping with awkward wrist postures as are known to increase the risk of development of CTS. While the panel agrees that the worker’s job duties do involve a variety of wrist and hand movements that require gripping and repetition, the evidence does not establish that these activities involved sufficient force, repetition, or use of awkward positioning so as cause development of bilateral CTS as defined in the AMA Guide relied upon by the WCB plastic surgery consultant.

The standard of balance of probabilities requires that the panel be satisfied that it is more likely than not that there is a causal relationship between the proposed occupational cause and the diagnosis. Here, the evidence is not sufficient to establish a causal relationship between the worker's specific job duties and their subsequent diagnosis of bilateral CTS.

The panel also noted the employer's position that there is evidence of a pre-existing condition; however, we considered that although the worker reported having similar symptoms previously, they did not seek any medical attention at that time and testified that they had no further symptoms until some point after 2020. We also noted the WCB plastic surgery consultant did not offer any comments as to the relevance of the worker's previous symptoms in relation to their present symptoms.

Based on the totality of the evidence before us and on the standard of a balance of probabilities, the panel is unable to find that the worker sustained injury arising out of and in the course of their employment. Therefore, the worker’s claim is not acceptable, and the appeal is denied.

Panel Members

K. Dyck, Presiding Officer
J. Peterson, Commissioner
S. Magian, Commissioner

Recording Secretary, J. Lee

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

Signed at Winnipeg this 27th day of August, 2026