Radial nerve entrapment by the lateral intermuscular septum after trauma

Radial nerve palsy is associated with humeral shaft fractures, usually occu rring at the time of injury but sometimes occurring later. We report on a c ase in which a progressive radial nerve palsy occurred three months: after a fracture; on exploration, the nerve was found to be trapped by the latera l intermuscular septum. It is important to recognize progressive radial ner ve palsies or late presentations, because they often represent chronic comp ression and a delay in exploration may be detrimental to the return of nerv e function.