Decision #93/09 - Type: Workers Compensation

Preamble

The worker is presently appealing a decision made by Review Office of the Workers Compensation Board (“WCB”) which determined that her bilateral carpal tunnel syndrome was not related to her work duties as an operating room technician. The worker disagreed with the decision and an appeal was filed with the Appeal Commission through the Worker Advisor Office. A hearing was held on August 13, 2009 to consider the matter.

Issue

Whether or not the claim is acceptable.

Decision

That the claim is not acceptable.

Decision: Unanimous

Background

The worker filed a claim with the WCB for right thumb and right wrist difficulties that she related to the following work activities:

“This is from repetitive motion. I work in the OR and hand instruments to the surgeon. It requires a twisting motion to attach syringes and other components to machines, and other instruments that need to be twisted on and off during an operation. Each surgery may last one half hour but we do 10 to 12 every day. I have pain in my right wrist and right thumb, and once I start performing my job duties it aches, and it is painful while I’m doing my job.”

The worker recorded an accident date of October 25, 2007 and reported to her employer on October 30, 2007.

On November 13, 2007, a WCB adjudicator contacted the worker to obtain additional information. The worker described her job duties as follows:

· she uses both hands to twist syringes and attachments (9 to 11 cases in one day);

· twists 8 to 12 things on and off;

· twists thumb towards fingers – attaches two ends to an instrument, the size of a pen. One hand twists away from her body and one towards her body.

· during eye surgeries, she squeezes the lever of a water bottle to provide moisture at the surgery site. She squeezes the bottle about 20 to 30 times and will alternate hands.

The worker indicated that she had mild symptoms in her left thumb but not as bad as her right. She took 20 minutes to half an hour for a case. There was a 5 to 10 minute break between each case. The worker advised that she worked 7.75 hours a day and worked 3 days a week. She had been doing the same job for 30 years. There were no changes in her job duties. The worker indicated that her symptoms began about three weeks ago. She had pain in her right thumb at the base of the thumb down into the wrist. The pain would go towards the elbow by the end of the day. The worker indicated that she was told she had arthritis. She wore a splint and was to remain off work until November 20, 2007.

The adjudicator also contacted the worker’s employer on November 27, 2007 to discuss the worker’s job duties. The employer noted that the worker complained around October 30, 2007 that her symptoms were caused by repetitive movements in her job. The employer noted that there were no other staff members with the same difficulties and they had no concerns with the claim.

Medical information on file showed that the worker was diagnosed with bilateral carpal tunnel syndrome (“CTS”) which was confirmed by nerve conduction studies dated December 12, 2007. A Physical Demands Analysis was also performed on March 4, 2008, by a WCB rehabilitation specialist.

On March 19, 2008, the worker was advised that the WCB was unable to accept responsibility for her claim. It was the opinion of the adjudicator that the work activities performed by the worker did not place her at risk for developing bilateral CTS.

On July 22, 2008, a worker advisor appealed the adjudicator’s decision to Review Office on the worker’s behalf. The worker advisor referred to an opinion expressed by an orthopaedic surgeon dated December 19, 2007 which related the worker’s CTS diagnosis to her work duties. She stated that the Physical Demands Assessment confirmed the orthopaedic surgeon’s opinion and demonstrated the presence of significant risk factors for CTS related to the worker’s work duties.

The worker advisor’s position was that the work duties performed by the worker satisfied the definition of an accident. She noted that while the worker did not perform one single activity continuously over the course of her workday, her various activities involved a combination of known risk factors for occupational CTS. The worker advisor indicated that should Review Office not find sufficient evidence to accept a direct cause-effect relationship, at minimum, the work duties were sufficient to cause an aggravation of an underlying CTS and her six days missed from work.

On August 13, 2008, Review Office confirmed the adjudicator’s decision that the worker’s claim for compensation was not acceptable. Review Office stated it was unable to find that the worker’s CTS was caused by her employment activities or that a pre-existing condition was aggravated by her employment activities. In support of its findings, Review Office relied on the following factors:

· the worker’s part-time work schedule limited her exposure to work tasks

· the job duties did not involve any degree of high repetition or high force

· as the worker’s CTS is bilateral, this suggested that the worker’s employment was not the cause of her CTS

· other medical conditions may be contributing to the worker’s symptoms, i.e. carpometacarpal osteoarthritis and pain was reported in the hand and at the base of the thumb

· Review Office was unable to accept that the worker had an aggravation of an underlying condition as there was no evidence to show that the worker had an accident to her left wrist or an accident to her right wrist;

· there was no evidence to establish that the worker had CTS prior to her nerve conduction studies carried out on December 12, 2007.

On January 29, 2009, the worker advisor provided Review Office with a further report from the orthopaedic surgeon dated December 29, 2008. The worker advisor stated:

“[orthopaedic surgeon] has indicated that, although [the worker] has several non-compensable factors which may predispose her to carpal tunnel syndrome, he does consider her work as an operating room technician to be a “significant contributing factor”.

It is our position that [the orthopaedic surgeon’s] opinion establishes that [the worker’s] employment duties contributed to a material degree in the development of the carpal tunnel syndrome.”

On March 17, 2009, Review Office confirmed that the claim for compensation was not acceptable. Review Office’s opinion was that the information provided by the orthopaedic surgeon dated December 29, 2008 and the attached medical literature did not demonstrate the worker’s bilateral CTS condition arose out of her employment duties as an operating room technician. On March 25, 2009, the worker advisor appealed Review Office’s decision to the Appeal Commission and a hearing was arranged.

Reasons

Applicable Legislation:

The Appeal Commission and its panels are bound by The Workers Compensation Act (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 assisted by a worker advisor at the hearing. The position advanced on behalf of the worker was that the CTS is a compensable condition related to her work duties. It was acknowledged that there were other factors present in the worker’s case which medically have been associated with increased incidences of CTS, but it was noted that CTS often develops from a variety of causes. This in and of itself does not preclude acceptability of a claim as long as work factors are found to have played a material role in the condition. The worker relied on a report from the treating orthopedic surgeon who wrote that while the worker was likely more susceptible than the general population to developing carpal tunnel syndrome, her work nevertheless was “a significant contributing factor.”

Employer’s Position

An advocate appeared at the hearing on behalf of the employer. It was the employer’s position that the WCB’s decision to deny the claim was correct, made only after careful consideration of the medical information and the onsite assessment of the work duties. There was no substantive evidence to support the worker’s argument that her bilateral CTS arose out of and in the course of employment. It was not established that the work duties either caused or aggravated the condition. The preponderance of information on file and the evidence from the hearing showed that the worker’s condition was caused by noncompensable factors unrelated to the workplace.

Analysis

To accept the worker’s appeal, we 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, we must find that her bilateral CTS arose out of and in the course of her work duties. Based on the evidence before us, we are not able to make that finding.

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, overweight individuals, smokers and people genetically pre-disposed to the development of CTS are also at increased risk for the development of CTS. It can also be caused by some work activities. There remains considerable debate in the medical literature as to what work factors may cause CTS. Occupational factors most 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 must carefully examine the worker’s job duties to determine whether, on a balance of probabilities, they might have caused or aggravated her bilateral CTS.

After considering the evidence as a whole, we are unable to find that the work duties contributed to the CTS, either causally or as an aggravation. The duties being performed by the worker were not the kind which are typically associated with the development of carpal tunnel syndrome. The worker described duties which involved considerable squeezing, pinching and twisting, however the panel was of the view that the work did not involve sufficient force nor repetition in an awkward position. Although the Physical Demands Analysis indicated that there may be rapid work required for up to 10 minutes, the remainder of the worker’s tasks were varied. The pinching motions associated with applying tubing and syringes took only seconds to complete and were not performed on a continual prolonged basis. The worker had to apply firm pressure to attach tubes and operate syringes, but the required force was not so great as to cause shaking of her hands. The work was performed directly in front of the worker at a comfortable level and there was no issue regarding the need to sustain an awkward position. She also worked a .6 position, which normally only required her to work 1-2 days in a row. Only on the rare occasion did she ever have to work three consecutive days in a row. Overall, there simply was not the degree of repetition, force, or awkward movement which would typically be associated with CTS.

The panel also places significance on the fact that the worker’s condition is bilateral, which in itself suggests a non-work related etiology. Further, the worker’s evidence was that most of the syringe work was done with the right hand, with the left hand simply holding the body of the syringe steady. This evidence would not support a finding that there was a significant amount of repetitive work being performed with the worker’s left hand such that CTS would be caused.

Given the foregoing and the fact that several other etiological factors (such as underlying medical condition, age and gender) are present in the worker’s profile, the panel finds that it is more likely that the CTS was caused by factors other than her work duties.

The panel also gave consideration as to whether the worker’s pre-existing CTS was aggravated by her work duties. We have concluded on a balance of probabilities that there was no aggravation. The pinching and grasping duties being performed by the worker were not markedly different than the same type of activity which a person would perform in their daily life. As noted earlier, we found that there was not a significant degree of repetition in performing the tasks. More importantly, however, the panel noted that the worker suffered the most severe worsening of her pain in October 2007. It was during that period in which she incurred time loss related to debilitating pain in her right hand. It was notable, however, that after she returned to work, the worker resumed the exact same duties and experienced no recurrence of the debilitating pain in her hand. She continued to do the pinching and pulling tasks, yet was able to continue working in her position until February 2009, when she discontinued work for reasons unrelated to her CTS. In the circumstances, the fact that the debilitating pain did not return when she returned to the same job duties suggests that the October 2007 aggravation was not caused by the work duties. There is a lack of a temporal link between the worsening of symptoms and the performance of her job duties.

Based on the foregoing reasons, the panel is unable on a balance of probabilities to relate the worker’s carpal tunnel syndrome to the work duties which were being performed by her as an operating room technician. The worker’s appeal is therefore denied.

Panel Members

L. Choy, Presiding Officer
A. Finkel, Commissioner
P. Walker, Commissioner

Recording Secretary, B. Kosc

L. Choy - Presiding Officer

Signed at Winnipeg this 5th day of October, 2009

Back