Occupational Musculoskeletal Disorder Case Study

University of Alberta
Edmonton, Alberta, Canada

Instructor(s): Guidotti, Tee L.
Subject area: Health / Medicine
Department: Faculty of Medicine
Level: Undergraduate Medical
Number of participants: 115
Duration of exercise: 1 hour
Learning objective: Develop Group Skills, Provide Information
Teaching style: Group Activity

Please note that the copyright for this course project is retained by the instructor.

This case study was used in an introductory, required course on occupational and environmental medicine for Phase III medical students at the University of Alberta Faculty of Medicine. The case describes shoulder and neck pain experienced by a 41 year old employee of a garment manufacturing company. The case describes nerve entrapment syndrome in detail. The students read the description and answer a set of questions pertaining to the case. Students are encouraged to work in teams.

Patient 1 is a forty-one year old former employee of a garment manufacturing company from 1977 to 1988. On 15 September 1986, she experienced the onset of left shoulder and neck pain and subsequently noticed numbness in an ulnar distribution of her left hand, primarily involving the fifth digit. This was worse when she used her hands repeatedly. She was initially given wrist supports but these made her condition worse. She also noticed the onset of right-sided discomfort, and numbness affecting digits four and five of her right hand. She was evaluated with nerve conduction studies, which showed entrapment of the ulnar nerve on both sides and a carpal tunnel syndrome of her left wrist. She is right-handed.

She underwent surgery twice, in June 1988, for release of a nerve entrapment at her left elbow and wrist and in February 1989 for release of nerve entrapment at her right elbow only. Since then, she has been much improved with respect to the pain in her upper extremities but still has pain in her left shoulder and neck, particularly with exertion.

Her duties at the company involved working on a sewing machine stitching jeans. She worked hunched over the machine, using her left arm and hand repetitively and vigorously to handle the heavy fabric while it was being sewn. In order to hold on, she had to grip very tightly continuously through the operation. She noticed little vibration, however, as she did not touch the machine but held on to the garment by the fabric.

A claim to the Workers' Compensation Board was initially denied on the grounds that her conditions were related to other medical problems, specifically a thyroid condition. Patient 1 had undergone radiation ablation of her thyroid with radioactive iodine, presumably for early thyroid cancer, and has done well on thyroid replacement since.

She immigrated to Canada as a young adult and had less than a high school equivalent education prior to leaving her native country.

On physical examination, the scars from her surgery are visible. An Adson's maneuver was negative, as was Phalen's test. She appeared to be depressed and tearful and her English skills were poor.

Nerve entrapment syndromes from repetitive strain and overuse are common and the garment industry is notorious as a source of these problems. The constant gripping and repetitive movement in an awkward position are very compatible with the subsequent development of this patient's nerve entrapment problems and certainly the musculoskeletal complaints affecting her neck and shoulders. It is particularly noteworthy that her problems are particularly severe on her left side, although she is right-handed. This is easily explained by the requirements of her job and there is no other plausible medical reason for this localization. Furthermore, it makes little sense that her musculoskeletal and nerve entrapment problems would be associated in any way with her thyroid condition. In the first place, the presentation of any thyroid disease, including extreme hypothyroidism, in this form in isolation would be such a remote possibility as to be inconceivable. Radionuclide ablation of the thyroid with appropriate replacements is an extremely benign treatment with few side effects. If there is any thought of her neck pain being associated with a thyroid disorder, this is not credible. Nothing else in the patient's medical history suggests an alternative cause for her musculoskeletal pain.

There is no reasonable doubt that her nerve entrapment and musculoskeletal pain is a direct consequence of her work. She experienced considerable relief following surgery, precisely as would be expected from nerve entrapment associated with overuse and repetitive motion. She has had residual pain in her neck and shoulder localized to the site primarily involved in her work. This has not been affected by surgery, and indeed one would not expect it to be relieved in this manner. Musculoskeletal disorders of this type, affecting soft-tissue structures primarily, persist quite long after the offending motion and load at work have ceased. She is permanently/partially impaired by her residual chronic pain and neck and shoulder discomfort. It was strongly advised that she not return to work requiring heavy and repetitive use of the upper extremities. Her lack of command of English and her limited educational level make it difficult for her to obtain alternate employment, however. Eventually, she was awarded permanent disability following an appeal to the Workers' Compensation Board. The consulting physician offered to refer her to a physician specializing in chronic pain control and coping with the sequelae of injuries but she declined, stating that her depressive reaction was strictly a matter of frustration and having her problem recognized.

Name: ____________________

I.D. No.: ___________________
Case Study #1

Maximum time required: 30 Minutes

Please turn in only the blue sheet.

Credit given for completion of exercise. You are welcome to work in teams.

1.a. What do you think is the principal hazard in this situation?

b. How would you confirm your impression?

2.a. What do you think is the principal health outcome of concern in this situation?

b. How would you confirm your impression?

3.a. How can this situation be corrected and further problems prevented in the future?

b. What is the physicians role in prevention in this situation?

4. Are the workers with health complaints fit to return to work in their usual occupation without presenting an excessive risk to themselves or others?

___Fit with restriction:___________________

5. On a scale of 1-10 where 10 is highest, how interesting did you personally find this material?

This document was last modified on 06/14/2000 03:07:50 PM

This resource was acquired by CEEM (Consortium for Environmental Education in Medicine), a program of Second Nature, under the auspices of a NIEHS grant to gather and disseminate environmental health educational resources over the internet in order to help medical and allied health sciences faculty identify, locate and use resources for incorporating environment and health perspectives into their curricula. CEEM has authorized the use of these materials on this website for archival purposes. Please note that the copyright for this material is retained by the instructor and/or contributing institution.