In a prospective study in which we attempted to identify the etiology of
postoperative ulnar-nerve palsy, 6,538 patients were followed through
surgery and convalescence. In seventeen patients (0.26 per cent), an
ulnar-nerve palsy developed at varying times during the postoperative
period. Of these seventeen patients, all were re-evaluated at an average of
six months and eleven were re-evaluated at an average of three and one-half
years after operation. Bilateral nerve-conduction studies were done on all
seventeen patients during the initial visit and on five of the eleven who
were re-evaluated at an average of three and one-half years. Abnormal
slowing of the conduction times was found in both nerves, suggesting a
possible predisposition to this condition. Based on the results of the
study, it is suggested that many patients may have a subclinical ulnar
neuropathy that may become symptomatic as a result of the many maneuvers
and manipulations that are associated with surgical procedures.