A Method for modeling long-duration joint motion

Musculoskeletal disorders of the upper extremities, in particular the wrist and the shoulder, have become the largest class of injury in workers´ compensation claims in the United States. Monitoring the development, progression, and treatment of degenerative orthopedic diseases, such as carpal tunnel and shoulder impingement syndrome, may be more effective when joint motions are assessed over long durations in real-world settings rather than controlled movements in standardized assessment and exercise protocols. Noninvasive long-duration measurements of joint motion would allow the standardized protocols to be quantitatively individualized and/or refined. In order to record three-dimensional joint activities over durations of eight or more hours, a portable, autonomous data logging system, using bi-axial electrogoniometers, was developed. Initial study results placed electro-goniometers on the shoulders and wrists of several subjects and demonstrated that variations in joint motion for multiple occupational settings between individuals can be quantified for the wrist. Based on the data collected, the cumulative effects of repetitive joint motions, which are a significant biomechanical risk factor in the development of work-related musculoskeletal disorders, can be accurately measured over long durations to provide detailed models of joint health in real-world scenarios.