Short Term Assessment of Functional Results of Bipolar Hip Arthroplasty

INTRODUCTION: Bipolar hip arthroplasty is done using a low friction, total prosthesis that has motion at two bearings unlike the conventional unipolar prosthesis. The advantages of bipolar hip arthroplasty are better stability, rapid rehabilitation and reduced acetabular erosion on long term. Bipolar is indicated in younger and older age groups. It provides excellent functional results in fracture neck and trochanter of femur in older age group and chronic arthritis and osteonecrosis of femoral head in younger age group. It has extended use in tumor surgery and revision total hip Arthroplasty. Bipolar in fractures of neck and trochanter provides better pain relief, allows early rehabilitation and ambulance of older individuals thereby preventing complications of prolonged convalescent period. In younger individuals, bipolar hip arthroplasty provides an excellent functional result in chronic arthritis and osteonecrosis of femoral head. The movements in the inner and outer bearing are complementary to each other and thereby providing increased range of motion post operatively. Availability of wide range of sizes, wide spectrum of use from simple fractures to complex revisions and flexibility between cemented and uncemented procedures confirms it as one of the best prostheses. AIM: The aim of this study is to assess the short-term functional outcome of 60 cases of bipolar hip arthroplasty surgeries done in our institution during the period July 2004 to September 2006. MATERIALS AND METHODS: This is a prospective study conducted at Department of Orthopedic Surgery, Government General Hospital, Chennai-3 during the period from July 2004 to September 2006. We had done 63 bipolar hip arthroplasty surgeries in 60 patients for varied indications. The study included 33 males and 27 females. The age ranged from 18-85 years, average being 53.1 years. Thirty-five Right hips and 28 Left hips were replaced. Out of 63 hips, 41 hips were treated for fractures of femoral neck, 20 hips were treated for degenerative arthritis of various etiologies. One patient expired 1 month post operatively due to myocardial infarction and one patient was lost for follow-up. Lateral approach was used for 45 cases and the remaining 18 cases were operated by posterior approach. Out of 63 hips, 42 were uncemented and 19 hips were cemented. All the patients were operated under spinal anesthesia or epidural anesthesia. RESULTS: In this study, we have analyzed the functional results of the bipolar hemiarthroplasty, done in 63 hips of 60 patients, in Government General Hospital, Chennai during the period June 2004 to September 2006. All patients were evaluated clinically and radiologically preoperatively and at various follow up periods. All the patients were analyzed using Modified Harris Hip Score. Based on the Harris Hip Score (HHS), the results were divided into excellent, good, fair and poor as below: Excellent : > 90 points, Good : 80-89 points, Fair : 70-79 points, Poor :