Nerve injury in repetitive motion disorders.

Nerve compression in repetitive motion disorders is being recognized with increasing frequency. The pathophysiology of chronic nerve compression spans a broad spectrum beginning with subperineurial edema and progressing to axonal degeneration. These changes depend on the amount and duration of the compressive forces. Certain postures or positions in the upper extremity will increase pressures around certain nerves increasing pressure exposure. Evaluation of these patients with chronic nerve compression should include examination at all levels of potential entrapment in the upper extremity to identify all sites of compression.