by Lewis B. Millender, MD
Lewis H. Millender, MD, is clinical professor of orthopaedic surgery, Tufts Medical School, and chief, occupational medicine, New England Baptist Hospital, Boston.
The issue of causality of musculoskeletal conditions to one's employment is controversial and is being discussed in various medical and government arenas. The subject was passionately debated at the recent Academy course on upper extremity disability in October 1995. The issue also was addressed by Graham Lister, president of the American Society for Surgery of the Hand, in a recent editorial in the Journal of Hand Surgery.1
The difficulty in arriving at definitive answers is twofold. From a medical/scientific point of view there are numerous conflicting positions regarding causal relationship and there are inadequate and insufficient controlled studies to definitively establish causal relationships. Additionally, causal relationship of disability to employment has become a sociopolitical issue with decisions based on different state legislation plus legal decisions.
From a scientific point, several positions are popular regarding etiology of musculoskeletal disorders:
1. Armstrong and Silverstein feel that forceful usage and repetition of the hand are responsible for these conditions and therefore the conditions are job-related.2
2. Kasdan and Hadler feel these "aches and pains" are related to normal usage and aging. They would state that the workers compensation system encourages workers with expected musculoskeletal discomfort to become litigants leading to prolonged disability and legal confrontation.3,4
3. Ireland proposes from his studies in Australia that many of these chronic conditions are related to psychosocial stresses both at the workplace and home.5
4. Recently, several surgeons have begun to relate some of these vague conditions to entrapment of the cervical nerves in the neck or the thoracic outlet.6
5. Some rheumatologists attribute some of these conditions to variants of fibromyalgia.7
How should we, as treating physicians, respond to these controversial, unexplained, and difficult issues? First, we must be careful how we label a patient's complaints. When a patient has clear cut symptoms of lateral epicondylitis, carpal tunnel syndrome, or subacromial bursitis, these are clear diagnoses. However, the label of cumulative trauma disorder, repetitive strain injury, or overuse syndrome implies causation and should be avoided.
When a worker has vague, unexplained arm pain with no positive physical findings, the diagnosis should be unexplained arm pain. Tendinitis, bursitis, and ligament strains have specific findings and patients with vague wrist or arm discomfort should not be labeled with a diagnosis of tendinitis. Not only is this inaccurate, but it gives the patient the impression that they have a serious condition which only exacerbates their symptoms. It is much better to reassure the patient and state that the discomfort is not serious and will resolve.
What is our responsibility to the insurer, employer, and plaintiff attorney in the area of causal relationship? Obviously, objectivity and honesty is the principal. There are obvious situations where upper extremity musculoskeletal symptoms are job-related. Chipping paint for eight hours a day for four days can cause extensor tendinitis. Long standing overhead work can cause rotator cuff pathology. These are clearly job-related.
How do we deal with causal relationship in more difficult cases? Does word processing for four hours a day cause carpal tunnel syndrome? Does counting money in a bank cause long-standing tendinitis? What should our position be when the hotel housekeeper has four months of persistent trapezium pain with no objective findings and fails to respond to conventional treatment? When one is unsure, this should be stated in a carefully balanced statement. One might state that the condition could have been aggravated by the work condition. One might state that the findings do not substantiate the complaints or that the complaints seem out of proportion to the physical findings.
I would caution physicians to use restraint when addressing causal relationship either as the treating physician or the independent evaluating physician. Let us battle this issue in journals and scientific meetings and develop more data regarding causality. However, to categorically deny that the job may have been a factor in a work-related disorder can be devastating and hurtful to a patient. I have seen this approach result in prolonged litigation and prolonged disability until finally the courts will almost always rule in favor of the patient after enormous distress and hurt has occurred.
As physicians our goal is to heal. Moderation and caring support for the patient will minimize disability and restore workers to the job. We must gather more scientific data and knowledge and then develop more uniform legislation and judicial positions before we can take hard stands regarding causality.
1. Lister GD: Ergonomic disorders. J Hand Surg 1955;20A:353.
2. Silverstein BA, Armstrong TJ: Hand and wrist cumulative trauma disorders in industry. BrJ Ind Med 1986;43:779-784.
3. Vender M, Kasdan M: Upper extremity disorders: A literature review to determine work-relatedness. J Hand Surg 1955;20A:534-541.
4. Hadler NM: Occupational illness: The issue of causality: J Occup Med 1984;26:587-593.
5. Ireland DCR: Psychological and physical aspects of occupational arm pain. J Hand Surg 1988;13:5.
6. MacKinnon SE, Novak CB: Clinical commentary: Pathogenesis of cumulative trauma disorder. J Hand Surg 1944;19A:873-883.
7. Goldenberg DL: Fibromyalgia syndrome. JAMA 1987;257:2782.