OBJECTIVETo study the efficacy of acetabular antiprotrusio cage for the reconstruction of acetabular bone defect in revision hip arthroplasty.

METHODSTwelve cases of severe acetabular bone defect after total hip arthroplasty were revised with antiprotrusio cage and bone grafting from February 2003 to October 2008. Clinical and radiological data before and after revision surgery were collected and compared for assessment.

RESULTSThe classification of acetabular bone defect of this group of patients according to Paprosky classification was: 2 cases of type IIB, 6 cases of type IIIA and 4 cases of type IIIB. The average postoperative follow-up period was 37 months (9 - 71 months). Mean Harris score of all cases was 35.2 before revision surgery, 80.9 at the first time follow-up and 84.6 at latest follow-up. There were no prosthesis loosening and breakage. There was mild radiolucent line in Delee & Charnley III zone of the acetabulum in one patient 6 month after revision, but no deterioration was found during further follow-up. No further revision was needed in this group of patients during the follow-up.

CONCLUSIONSReconstruction of acetabular bone defect using antiprotrusio cage and bone grafting is a useful method to restore the bone defect and stability of the acetabulum. The outcome via short to middle term follow-up is encouraging.