Although bipolar hemiarthroplasty of the hip is a frequently performed
procedure, little information is available about the frequency of pos
toperative dislocation and its treatment. For this study, 1,934 hips t
reated consecutively with primary bipolar hemiarthroplasty were review
ed. A postoperative dislocation developed in 29 patients (1.5%): durin
g the first month after surgery in 24 patients and between 1 month and
5 years after surgery in 5 patients. Of the 29 dislocations, 25 were
successfully reduced with routine closed methods. Among these 25 hips,
13 (52%) subsequently redislocated, and 7 of these required operative
treatment for the recurrent dislocation. Dislocation after primary bi
polar hemiarthroplasty is infrequent, can usually be reduced by routin
e closed methods, but is associated with a high rate of recurrent disl
ocation.