Abstract
A case of posterior interosseous nerve paralysis resulting from a constricting band is repored. A 35-year-old man complained of weakness in his left hand. Extension of the thumb and fingers was weak, and a so-called finger drop deformity was present. A constriction of the posterior interosseous nerve was found proximal to the supinator muscle. No other compressive force was noted along the course of the nerve. The constriction seemed to be caused by local torsioning of the nerve itself. When the forearm was pronated, the torsion became severe. The torsion point was released by gentle neurolysis around the constricting site. Four months later, full function returned to the left hand.
