Upper extremity cumulative trauma disorders became a potentially significant occupational hazard among sign language interpreters at the National Technical Institute for the Deaf in the 1988-89 academic year. The following case control study was conducted to identify factors that might play a role in developing, exacerbating, and maintaining upper extremity cumulative trauma disorders among interpreters. Investigations were conducted to determine whether medical status, physical capacities, interpreting styles, pain, fatigue, and job stress differed among NTID's sign language interpreters. This report provides a general summary of selected findings as well as a conceptual framework that should help clarify the factors associated with upper extremity cumulative trauma disorders in sign language interpreters.
The results indicated that the upper extremity cumulative trauma disorder diagnosed most often is tendinitis rather than a nerve entrapment syndrome (e.g., carpal tunnel syndrome). Analysis of the frequency of potential biomechanical risk factors indicated that those reporting pain demonstrated higher frequency of hand and wrist deviations from the neutral position, higher frequency of the upper extremities leaving a predefined workspace, fewer rest breaks during interpreting sessions, and higher evaluator ratings of pace of finger and hand movements. Specific features of interpreting styles were associated with increased pain and fatigue.