Occupational injury and illness of the thumb. Causes and solutions.

1. The special functions of the thumb (opposition, retroposition, palmar abduction, and radial abduction) account for up 50% of overall hand use. 2. Knowledge of specific questions to ask on history taking and proper initial evaluation can help with timely and appropriate referrals for suspected thumb fracture, dislocations, and/or torn ligaments. 3. Repetitive and/or forceful thumb movements can aggravate or cause the following cumulative trauma disorders: stenosing tenosynovitis ("trigger thumb"), de Quervain's tenosynovitis, and carpometacarpal joint arthritis. 4. The occupational health nurse can suggest many ergonomic solutions to decrease thumb motions and forceful thumb pressures encountered at work.