How does radial nerve entrapment occur?
Improper positioning during anesthesia, sleeping (or lying) on the arm, or improperly fitting crutches can result in prolonged compression of the nerve along the radial groove on the humerus. This results in wrist-drop, referred to as Saturday night palsy because it often occurs while the patient is intoxicated. Decreased sensation in dorsal web space can also occur. The posterior interosseous nerve, a motor branch of the radial nerve, can be impinged at the elbow (RA synovitis) with resulting weakness in finger extension at the metacarpophalangeal joints.