ACETABULAR RECONSTRUCTION USING BIPOLAR ENDOPROSTHESIS AND BONE-GRAFTING IN PATIENTS WITH SEVERE BONE DEFICIENCY

Eighty-one patients who had hip reconstruction with bone grafting and bipolar endoprosthesis for severe acetabular deficiency were reviewed retrospectively at 3 to 8 years postoperatively, Failed total hip arth roplasty was the most common indication for operation, Bone grafts wer e fixed bone blocks, morselized cancellous bone, and wafer-type grafts used singly or in combination, The average Harris hip rating score wa s 49.9 points preoperatively, 81.4 points at 1 year, and 70.8 points a t latest followup examination, The 35 unsuccessful procedures included 25 reoperations for implant removal (resection arthroplasty or revisi on) and 10 cases pending revision, At latest followup examination, 54. 7% of patients considered themselves improved and 62.7% had no or mild pain, Eighty-five percent of cases had radiographic evidence of compo nent migration that was superior and medial in direction, Overall prob ability of implant survival was 96% at 1 year, but only 47% at 6.5 yea rs postoperatively, Because of the high failure rate, this procedure h as a limited role in hip reconstruction, but may be a reasonable part of a staged reconstruction for patients with massive bone loss or in c ertain revision cases where instability is a concern.