Postoperative ulnar-nerve palsy. Are there predisposing factors?

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.