Baseline examination of 1,214 North American automobile manufacturing workers found that:
• 41 percent experienced upper extremity symptoms
• 23 percent had a specific upper extremity musculoskeletal disorder (UEMSDs) as per case definition of eight syndromes
• 45 percent of those with a specific UEMSDs had two or more conditions
• 18 percent had non specific UEMSDs (signs/symptoms that do not conform to traditionally accepted diagnostic indications of a specific disorder)
Subjects were examined on three occasions (in 1992, 1,198 subjects; in 1993, 771 subjects; in 1998, 506 subjects). This study compared the prevalence of disorders between the worker groups at the three separate times over the six years. The most common diagnosed disorder was tendinitis:
• At the shoulder, 70 percent had rotator cuff tendinitis at baseline which increased to 80 percent at both follow-up evaluations
• At the elbow, approximately 50 percent had medial or lateral epicondylitis at baseline, which rose to approximately 66 percent at first follow up and 70/80 percent at second follow up.
• At the hand/wrist, baseline findings showed an equal distribution of de Quervain’s disease, hand/wrist/forearm flexor tendinitis and hand/wrist/forearm extensor tendinitis; over the six years, these conditions diminished slightly in incidence
• Approximately 10 percent of those with hand/wrist/forearm symptoms were diagnosed as having carpal tunnel syndrome; an increase was found at the second evaluation followed by a decease at the third assessment
Only 365 subjects were seen at all three evaluation times. Approximately 25 percent of the baseline non-specific disorders progressed to a diagnosed UEMSD at the one year follow-up. This pattern continued to the six year point.
The Bottom Line – How This Applies To Ergonomists
Although this study draws on information collected in the 1990’s, it is reasonable to assume upper extremity conditions continue to occur at a high rate among automobile manufacturing workers. Also, in general, a reporting of non-specific upper extremity symptoms related to a task/job should be taken seriously. This study found that nearly a quarter of the time, a clinical condition developed over a one year period.
Other Key Points
At all three examination times, the most common specific conditions were rotator cuff tendinitis and de Quervain’s disease.
A higher percentage of subjects with a specific case type at baseline were on temporary illness/injury/disability or other permanent separation at the six year evaluation compared to baseline non-case types.
This position paper can be acquired at: http://www3.interscience.wiley.com/journal/121641637/issue
Article Title: Specific and Non-Specific Upper Extremity Musculoskeletal Disorder Syndromes in Automobile Manufacturing Workers
Publication: Journal of Industrial Medicine, 52:124-132, 2009
Authors: J E Gold, A d’Errico, J N Katz, R Gore, and L Punnett
This article originally appeared in The Ergonomics Report™ on 2009-03-11.