Revision of total hip arthroplasty using uncemented extensive porous-coated femoral components / 中华骨科杂志

ABSTRACT

Objective To demonstrate the clinical results of the patients with failed cemented femoral component due to aseptic loosening with extensive porous-coated femoral implants. Methods Be-tween 1998 and 2003, twenty hips (20 patients) with a failed cemented femoral component were revised us-ing extensive porous-coated femoral components and allograft. There were 12 males and 8 females. The mean age of the patients at the time of revision was 64 years (41-77 years). All of the revised femoral com-ponents were cemented stems,with first-generation cement technique in 18 hips and second-generation ce-ment technique in 2 hips. The indications for hip arthroplasty included osteonecrosis of the femoral head in 14 hips and femoral neck fracture in 6 hips. The interval from primary hip arthroplasty to revision surgery ranged from 5 to 17 years, with an average of 11.5 years. There were 4 re-revisions in this group. Based on Paprosky classification for bone deficiency, 3 hips were of type I, 6 of type II and 11 of type IIIA. The com-ponents implanted included AML (DePuy) in 5 cases , Solution (DePuy)in 7, full-coated (Zimmer)in 6 and Perfecta Extend Stems (Wright Med) in 2. The postoperative stability was evaluated according to the Engh criteria. The patients were followed for an average of 40 months (18-60). Results At the latest fol-low-up, the mean Harris score was improved from 40 to 85 points postoperatively. The bony ingrowths were found in 17 hips and the fibrosis stability in 3 on postoperative radiographic evaluation. There were no re-revisions in this group. The bone remodeling was observed in all osteolytic zones. Conclusion In the pres-ence of bone loss in the proximal metaphyseal region of the femur, the extensive porous-coated femoral com-ponents may provide a bypass for the deficient proximal bone. It may further obtain initial optimizing pros-thesis-bone fitting and an axial anti-rotational stability in the relatively normal diaphyseal region of the fe-mur to allow the reliable biological fixation with bony ingrowths.