To the Editor.—
Peripheral nerve entrapment syndromes are common and may cause pain and dysfunction in a normal-appearing limb. These may arise from unusual activities, as in the following case.
Report of a Case.—
A 35-year-old woman had been well until, for the first time, she engaged in several hours of vigorous Frisbee-throwing. Transient mild pain in the right shoulder and elbow was followed in five days by inability to extend the right wrist or fingers. Palpation anterior to the right lateral epicondyle produced pain, and there was weakness of the right wrist (20% of normal) and finger (40% of normal) extensors as well as supinator weakness (50% of normal). Other muscle function was normal, as were sensation, reflexes, and roentgenograms of the right arm. Her strength slowly returned to normal.
This This case is an example of posterior interosseus nerve entrapment due to "Frisbee-flinging." The pathophysiologic mechanism is