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Work-related bilateral osteoarthritis of the first carpometacarpal joints.

BACKGROUND
A 44-year-old industrial worker produced panels for folding doors for 9 years. During this period, he developed osteoarthritis (OA) of both first carpometacarpal joints. Surgery was performed without improvement.


METHODS
Clinical examination, demonstration and recording of work conditions, with photos and videos. The literature concerning first carpometacarpal OA was reviewed using PubMed.


RESULTS
The observation of work conditions demonstrated unusual forceful and repetitive ulnar flexion of both first fingers. No competing causes of OA could be identified.


CONCLUSION
This patient had specific and intense work-related strain of both first carpometacarpal joints. A good temporal relation between work exposure and disease development was demonstrated and it appears likely that the OA was caused by work. However, there is very limited epidemiological evidence relating first carpometacarpal OA to work exposure.