The Appeal CommissionThe Workers Compensation Act of Manitoba

Applicable Legislation

The Appeal Commission and its panels are bound by the Act, regulations and policies of the Board of Directors. Subsection 4(1) of the Act provides:

4(1) Where, in any industry within the scope of this Part, personal injury by accident arising out of and in the course of the employment is caused to a worker, compensation as provided by this Part shall be paid by the board out of the accident fund, subject to the following subsections. (emphasis added)

The key issue to be determined by the panel deals with causation and whether the worker's bilateral CTS arose out of and in the course of her employment.

Worker's Position

The worker was represented by an advocate who made a submission on the worker's behalf.

The worker's representative submitted that the claim was acceptable under subsection 4(4) of the Act. He said that the dominant cause of the worker's wrist condition is her work duties. The representative clarified that the worker is left hand dominant only in relation to writing. In all other activities she uses her right hand or both hands. The representative disagreed with the Review Office comments regarding the worker's non-work risk factors for carpal tunnel.

The worker provided a detailed description of her job duties and answered questions from the panel. The worker advised that she has performed the same job, recreation aide in a personal care home, for 11 years. She said the number of patients she deals with has not changed. The worker said her job duties have increased over the last two years as one of the other staff in the area is required to perform more office work. Her duties include:

• organizing activities for residents of the care home. Many of the residents use wheel chairs and Broda chairs. Other residents use walkers. The number of residents involved in the activities varies but can exceed 25 residents of whom half use wheelchairs or Broda chairs. The worker pushes the wheelchairs to the activity room and assists those with walkers. After the activity is completed, she assists residents in going to other locations in the home. The worker then puts equipment away which can include stacking chairs and tables.

• taking residents on shopping and field trips. This involves loading and unloading the residents onto the bus, fastening and unfastening seatbelts, anchoring wheelchairs and driving the bus. In good weather the worker takes the residents for walks on the sidewalk near the home. This involves pushing wheelchairs and Broda chairs over rough sidewalks, and assisting residents use walkers.

• assists residents with restorative care, doing exercises prescribed by a physiotherapist.

• lifting patients and assisting other staff in moving patients and other activities.

When asked which activities involve vibration, the worker said pushing wheelchairs, Broda chairs and holding walkers. She said that jobs involving extreme flexion include pushing Broda chairs, moving a piano and stacking tables and chairs. She said forceful gripping was required when pushing heavy patients' wheelchairs and carrying plates. Pressure at the base of the palm occurred when pushing wheelchairs and lifting patients.

The worker sets up the activity room which involves moving chairs, tables, and equipment, including weights, carpet bowling balls and a piano. She then runs the activity which can include exercise, crafts, weights, shuffle board, and reminiscing.

The worker advised the panel that she has had surgery on both hands and is currently recovering.

Employer's Position

The employer was represented by an advocate who advised that the employer supports the worker's claim for WCB benefits and asks the Appeal Commission to overturn the WCB decision.

The advocate said that the WCB has not made a valid case that there is a non-occupational cause for the worker's CTS. He said that the worker performs repetitive duties on a daily basis and it is reasonable that the repetitive nature of her work would cause CTS. He noted that the worker performs the repetitive duties using both hands/wrists and submitted that it makes sense that she would develop CTS on a bilateral basis. He also noted Review Office accepted that the worker's duties involved lifting of weight, pulling, gripping and wrist flexion and extension.

The advocate stated that "In the absence of any plausible non-compensable cause for [the worker's] CTS, one must look at a balance of probabilities when determining the most likely cause of the CTS…We believe that the most likely cause is her work duties performed daily at the [care home] and we are therefore asking that this claim be accepted and benefits be paid accordingly."

Analysis

For the worker's appeal to be successful, the panel must find, on a balance of probabilities, that she suffered injury by a workplace accident within the meaning of subsection 4(1) of the Act. In order to do so, the panel must find that her bilateral CTS arose out of and in the course of her work duties. Based on the evidence before us, the panel is not able to make that finding.

The panel has considered the medical information on file and notes there is no dispute as to the diagnosis of the worker's condition, she has bilateral CTS. There is, however; a dispute as to what caused the worker's CTS.

CTS is defined as the impairment of the motor and/or sensory function of the median nerve as it traverses through the carpal tunnel. It is caused either by intrinsic swelling of the median nerve or by extrinsic compression of the median nerve by one of the many surrounding structures of the wrist. CTS has a variety of causes. It can be caused by underlying systemic conditions such as rheumatoid arthritis, osteoarthritis, hypothyroidism and diabetes. Middle aged females, individuals with a high body mass index, smokers and people genetically pre-disposed to the development of CTS are also at increased risk for the development of CTS.

It is accepted that work activities can cause CTS. Work factors commonly accepted to be associated with CTS include a wrist injury, frequent use of vibrating hand tools or any repetitive, forceful motion with the wrist bent, especially when done for prolonged periods without rest. It is generally considered that the greatest frequency of occupationally related CTS is found where the job duties involve high force and high repetition.

To decide this appeal, the panel has carefully examined the worker’s job duties to determine whether, on a balance of probabilities, they might have caused her CTS.

After considering the evidence on file and the worker's evidence at the hearing, the panel is of the opinion that the worker’s bilateral CTS is not causally connected to her work duties. The job duties identified by the worker are not consistent with the type of duties typically associated with the onset of CTS symptoms. The panel finds that the job is busy and involves use of both arms and hands. However, the duties are varied, are not done on a continuous basis, do not involve significant vibration, force, extreme flexion or pressure at the base of the palm. While the duties involve some gripping, pushing and pulling, they did not involve the degree of repetition, force, or awkward movement which would typically be associated with CTS.

The primary activities identified by the worker as being causative of her CTS condition was pushing residents' wheelchairs and Broda chairs and moving and stacking tables and chairs. The evidence demonstrates that these activities are not performed continuously rather are intermittent, being done between recreational activities, meals, other activities and breaks. The activities involves little vibration, force or flexion.