Injury of the axillary nerve subsequent to recurrence of shoulder dislocation. Clinical and electromyographic study.

Injuries of the axillary nerve subsequent to recurrence of glenohumeral dislocation have received only minimal attention. It is the purpose of this study to define the prevalence and the progression in time of injury of the axillary nerve in patients with recurrence of anterior shoulder dislocation. For two years we observed a total of 185 patients who had had primary shoulder dislocation. Excluded from the study were patients who had fractures associated with metabolic disorders that favored neurologic deficit. During the period of study, 98 patients contacted us again after recurrence of the dislocation: there were 89 patients aged over 60 years and 9 aged below 60 years. All of the patients were evaluated clinically and submitted to EMG in order to verify the condition of the axillary nerve. Four patients (4%) had neuroapraxia of the axillary nerve. One of these also had neuroapraxia of the radial nerve. Of the four patients, one was a male aged 34 years; the others were all aged over 60 years. In all of the cases, function of the axillary nerve completely recovered after a mean period of 4 months (3-5.3 months) after recurrence. Injury of the axillary nerve can occur at the time of the first recurrence of the injury. However, prevalence is significantly lower than that observed after primary dislocation. The occurrence of this injury should be taken into consideration, particularly in elderly patients, in order to avoid erroneous clinical diagnosis and massive rupture of the cuff subsequent to recurrence of the dislocation.