Decision #162/11 - Type: Workers Compensation
Preamble
The worker is appealing the decision made by the Workers Compensation Board ("WCB") which determined that his bilateral hand condition did not arise out of and in the course of his employment. A hearing was held on October 13, 2011 to consider the matter.Issue
Whether or not the claim is acceptable.Decision
That the claim is not acceptable.Decision: Unanimous
Background
On September 13, 2010, the worker filed a claim with the WCB for numbness in both hands that he related to his job duties that involved cutting and trimming. The date of accident was August 23, 2010 and the worker said he reported the injury to his supervisor on the same day.
The employer's report of injury stated that the plant was shut down from July 17 to August 8 inclusive and a green card was not filled out until August 23. The employer noted that the worker had been doing his current job duties since March 2010. The job duties included seat trim, dash and under-dash, and typical production tasks such as drilling, trimming, etc. Prior to this, the worker did sash preparation and installation beginning in November 2009.
The worker underwent Nerve Conduction Studies on September 17, 2010 and the findings were reported as being consistent with bilateral carpal tunnel syndrome ("CTS").
On September 23, 2010, the worker advised the WCB that he started to notice difficulties with both hands when he started his new job in March 2010. Approximately three weeks later, he developed symptoms of numbness in all fingers especially when he awoke in the morning. He had pain around the base of the thumb and wrist. The worker advised that he did not report his difficulties to his supervisor until August 23 as he thought his symptoms would go away. He did tell a co-worker that his hands were sore but he was not sure if the co-worker would remember.
On September 29, 2010, the worker's supervisor provided the WCB with a full description of the worker's job duties from November 2009 until March 2010. The supervisor said he first became aware of the worker's difficulties when the worker submitted a green card. The worker was a long term employee and knew that he should report any difficulties. When the worker's symptoms appeared, they were at a lower line rate. They were giving people multiple tasks to do but more time to do it.
A work site and job analysis was carried out by a WCB rehabilitation specialist on October 20, 2010. The following opinion was expressed:
Worker is required to use hands for all tasks. However, wrist movements are not sustained or repetitive in nature and there is a great variety in the types of tasks performed. No end range extension/flexion of wrists are observed. Worker is exposed to vibration on a rare basis through shift - when rimming or using electric drill. He uses both hands when rimming and right hand only when drilling.
On October 26, 2010, the worker was advised that his claim for compensation was not acceptable as the WCB was unable to relate the development of his bilateral wrist difficulties to an accident as described in subsection 1(1) of The Workers Compensation Act (the "Act"). On November 24, 2010, the worker appealed the decision to Review Office.
On January 20, 2011, Review Office confirmed the decision that the worker's claim for compensation was not acceptable. Review Office indicated that it carefully considered the worker's job duties as described by the worker and employer documented on the file and the worksite/job analysis as seen on video footage. In the opinion of Review Office, the worker's job duties involved a variety of tasks and did not involve significant repetition or high force. There was no awkward sustained positioning of the wrists and vibration was minimal throughout the shift when rimming or using the electric drill. Review Office felt it was unlikely that the worker's bilateral CTS would develop in the course of three weeks.
Review Office noted that the rehabilitation specialist's worksite/job analysis had not observed the worker performing the job functions. Nevertheless, it was felt that the analysis was representative of the job requirements, the tools used and the duration and timing of the tasks involved throughout the day. The rehabilitation specialist had consulted the worker during her assessment. Review Office commented: "Although the evidence has not indicated any personal risk factors, the worker's CTS is bilateral which, as noted above, is frequently an indication of a non-work related condition. The Review Office finds, on a balance of probabilities, that the worker's job duties have not caused his bilateral CTS and that the claim is not acceptable." On April 4, 2011, the worker 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 carpal tunnel syndrome (“CTS”) arose out of and in the course of his employment.
Worker’s position
The worker was accompanied by a union representative at the hearing. The worker's evidence was that he had been off work for an unrelated condition and when he came back to work full time he was placed in a different position. After approximately three weeks on the job, he started to feel pain in his hand and he would wake up with numbness in the morning. He went to see his doctor who told him that he was just new to his job and that it would go away once he got used to it. The worker continued to work in the new position, but the condition did not go away. During a three week company shut down, he hoped that with rest his condition would improve, but it did not. Finally, his doctor decided to refer him for nerve conduction tests and it was discovered that the worker had CTS. The worker then filed a report with his employer, but continued to work, despite the pain. His attitude was that he did not want to stop working and even if he had pain, he would continue to do the work if he could.
Employer’s Position
The employer's health management specialist appeared at the hearing on behalf of the employer. The employer confirmed that the worker was a good worker and had been off work for a non-work related occurrence. When he returned, he was moved to a new position, which was common in the employer's manufacturing operation. The positions were quite variable and workers were often moved around. The employer agreed with the work demands as identified by the WCB occupational therapist and while the employer did not deny that the worker had CTS, it was submitted that the injury/problem with his hands did not arise directly from his work relationship with the employer.
Analysis
To accept the worker’s appeal, we must find on a balance of probabilities that he 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 his bilateral CTS arose out of and in the course of his 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, individuals with 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 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 contributed to his 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. At the hearing, the panel carefully reviewed the duties being performed by the worker, not only during the period from March to August 2010, but also the duties he performed earlier in his career with the employer. The panel's impression was that the duties being performed by the worker were not the kind which are typically associated with the development of carpal tunnel syndrome. The worker did describe some tasks which involved awkward positioning and strain to the wrists; however, these tasks were not performed for any great length of time. The worker’s tasks were varied and only seldom was he required to sustain a position for more than a few seconds. No significant amount of force was required. For the most part, the worker's wrists were in a neutral or only slightly bent position when operating power hand tools. None of the jobs which the worker identified as ones which caused him the most difficulty involved 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 assembly work was performed with his right hand. This evidence makes it difficult to explain why CTS would develop in both hands at an equal rate when the right hand was being subjected to more strain.
It is notable that when the worker stopped performing the duties during a three week plant shut down in July 2010, he noticed no improvement or change in his CTS condition. Further, he has since been transferred by the employer to a different assembly area which requires no strain on the wrists, yet the worker indicates that he continues to experience the CTS symptoms with no improvement in his condition. One would expect that if the work duties were the cause of the CTS, the symptoms would improve once the work duties were discontinued.
Finally, the panel notes that the worker had only been performing the impugned duties for three weeks before he began to notice issues with his hands. CTS is often understood to be a cumulative injury and absent an acute wrist injury, three weeks would be a very short period in which CTS would develop.
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 him as an assembly associate. The worker’s appeal is therefore denied.
Panel Members
L. Choy, Presiding OfficerA. Finkel, Commissioner
M. Lafond, Commissioner
Recording Secretary, B. Kosc
L. Choy - Presiding Officer
Signed at Winnipeg this 1st day of December, 2011