The Appeal CommissionThe Workers Compensation Act of Manitoba

Introduction

This appeal deals with claim acceptability. Central to this appeal is the relationship between the worker’s bilateral CTS and her work duties.

Background

The Work Duties

The worker has worked for the same employer doing full-time administrative duties for over 20 years. Approximately two years before the onset of her bilateral CTS, the worker’s work station and duties changed. Since that date, the worker rotates work stations once a week over a six week period.

Work stations 1 – 5 have computers, telephones and paging systems. Work station 6 is an “information” position. It is work stations 1 – 5 that the worker says are more likely to have caused her bilateral CTS.

While at each work station (1 – 5) the worker receives on average 500 calls per day. Most of these calls require her to use the paging system. The paging system requires the worker to push buttons down while making an announcement. While at work stations 1, 3, 4, and 5, she uses the fingers on her left hand to push down the buttons, though if the page requires several fingers, she also uses the fingers on her right hand; This happens about 50% of the time. While at work station 2, she uses the fingers on her right hand. She hold the keys for approximately 5 minutes while paging.

The worker also needs to reach forward to reach for the telephone and various books. Her typing is limited to entering a letter or name to retrieve page numbers.

The Onset of Symptoms

In about 2002 the worker began to notice some tingling and numbness in her first three fingers of both hands when she was riding the bus home at the end of her work day. Over time, these symptoms progressed into a “tired” feeling in her wrists. In 2004 she sought medical treatment for her symptoms and was diagnosed with bilateral CTS, severe on the right and moderate on the left.

The Medical Evidence on the Cause of the worker’s CTS

Several medical reports deal with the various risk factors associated with the worker’s bilateral CTS as well as the casual relationship with her work duties.

An April 19, 2004 referral letter from her family physician notes that the worker was 62 years of age with hypertension, obesity, Type II diabetes, gouty arthritis, diabetic peripheral neuropathy and diabetic foot ulcers.

The neurologist she was referred to in June 2004 thought that in addition to her bilateral CTS, she also had a more diffuse peripheral neuropathy.

The worker’s family physician thought that the worker’s job duties had caused her bilateral CTS. In a February 21, 2005 report he wrote:

“In my opinion, a causal relationship exists between the development of her bilateral [CTS] and her work related duties, tasks, and responsibilities at her job as a switchboard operator. For well over 20 years she has been using her hands on a repetitive basis at her job with movements and actions of keyboarding and typing causing ongoing, regular strain on her hands, wrists and fingers. Although the [worker] has a long history of pre-existing Type II diabetes dating from 1980 and evidence of diabetic complications involving nephropathy and recurrent diabetic foot infections, I am of the opinion that her hand difficulties are not secondary to any diabetic neuropathy but rather directly related to her bilateral [CTS] caused by repetitive strain at work for many years…”

An ergonomic assessment of the worker’s workstations was done by an occupational therapist on March 15, 2005. She found that the workstations could cause some physical difficulties for the worker but these were mainly with respect to upper back and neck difficulties. In particular, she found that it was the excessive reach for the paging equipment that could cause stress on the neck and back. There is no reference to a potential risk for the development of CTS. The only mention she makes with regard to risk factors for the development of CTS is the positioning of the keyboard which she found contributed to wrist flexion, a major factor in the development of CTS.

Worker’s Position

The worker says that her claim is acceptable. She says that although she has non-work related factors that put her at risk for the development of CTS, she has never had problems with her wrists before. She says that her wrist problems only began after her change in duties in 2000 that required her to use the paging equipment that requires forceful pressure in a non-neutral wrist position.

Employer’s Position

The employer says that the worker’s claim is not acceptable. It says that it is more likely than not that the worker’s bilateral CTS is due to the worker’s non-work related risk factors than her job duties.

In support of its position, the employer submitted several medical articles dealing with CTS.

Analysis

To accept the worker’s appeal we must find that she suffered an accident at work in accordance with subsections 4(1) and 1(1) of The Workers Compensation Act, and more particularly that the worker’s job duties caused her to develop bilateral CTS. Based on the evidence before us, we are unable to make that finding.

CTS has a variety of causes. It can develop as a result of pressure on the median nerve caused for example by 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 can also be caused by underlying conditions such as rheumatoid arthritis, ostearthritis, hypothyroidism, and diabetes. Middle-aged overweight females, smokers and people genetically pre-disposed to the development of CTS are also at increased risk for the development of CTS.

Given the variety of causes of CTS, it is extremely important to examine the worker’s job duties to determine whether on a balance of probabilities they might have caused her bilateral CTS.

In reviewing the worker’s job duties we are unable to find that they caused her CTS. While the worker asserts that the keypad of the paging equipment requires her to use forceful pressure with a non-neutral wrist position, this was not a finding of the occupational therapist. While the occupational therapist does not squarely dispel the worker’s evidence, the panel draws the inference that this particular duty was not a risk factor in the development of CTS given that she did not make any mention of it. While she does indicate that keyboarding could be a risk factor, the worker’s evidence is that she does very little typing and certainly no typing for extended periods of time.

Further, while the family physician takes the position that the worker’s job most likely caused her bilateral CTS, he bases this opinion on job duties that are not consistent with those of the worker. In particular, he states that the worker “has been using her hands on a repetitive basis at her job with movements and actions of keyboarding and typing causing ongoing, regular strain on her hands, wrists and fingers” for over twenty years. This is not the evidence before us. Further, the worker candidly stated at the hearing that she did not discuss her job duties in detail with her family physician. For these reasons we are unable to place any weight on the family physician’s opinion.

Based on the foregoing, we are unable to find on a balance of probabilities that the worker’s bilateral CTS was caused by her work duties. Although it developed contemporaneously with the change in her duties, we find that this was merely coincidental and not causative of her CTS.

Accordingly, we find that the worker’s claim is not acceptable.