Long thoracic nerve palsy: a follow-up study.

Twelve patients who had previously been treated for palsy of the long thoracic nerve of Bell and resultant serratus anterior paralysis were examined in a follow-up study designed to determine their extent of recovery and/or residual disability. The patients' histories were reviewed, following which they were recalled for updating of the history and reexamination. It was found that those patients whose lesions were due to acute trauma had only partial or no recovery of serratus function, while those with infectious, toxic, allergic or idiopathic etiologies had partial or complete recovery. The occurrence of a prolonged interval between onset of symptoms and institution of therapy was found to adversely affect prognosis. Among those patients with no recovery of serratus anterior function, some were able to maintain relatively good active motion in the affected shoulder by substituting with the trapezius.