Abstract
Introduction
Loss of bone stock is a technically challenging problem in revision total hip arthroplasty (RevisionTHA). Impaction bone grafting (IBG) is an attractive biological method of reconstruction. We performed acetabular revisions using IBG and cemented cup in patients with failed hip prosthesis and large defects. The purpose is to report the short term results of revision THA with using IBG.
Patients & Methods
We retrospectively reviewed 19 patients/19 hips revised for aseptic loosening of a cemented or uncemented cup, three male/16 female, mean 65.5 ± 8.8 years old (43–75). Mean follow up time is 18 months. Classification of acetabular defects according to A.A.O.S classification were Type I; 5 hips, Type III; 13 hips and Type V; 1 hip. Before impacting the morselized bone allograft and cement, segmental acetabular defects were reconstructed with metallic meshes screwed to the bone bed. Morselized allograft bone chips (diameter 7ï¼ 10 mm) were impacted forcefully. All-polyethylene cups (Stryker, Crossfire) were cemented. Clinical examination was performed using Japanese Orthopaedic Association (JOA) score. Radiographic examination was performed using AP radiographs. We measured the inclination cup angle, the distance of superior migration, the presence of loosening of the implanted cup, 4 weeks postoperatively and at the last follow up. Loosening was defined as migration distance was more than 5 mm in any direction.
Results
Clinical JOA score improved from 61.0±3.9 to 83.6±2.7 at the last follow up. Complication in this study included one sciatic nerve palsy and one dislocation. In the radiographical analysis, inclination angle changed 41.8 ±2.2° at 4 weeks postoperatively to 42.3±1.8° at the last follow up. The average superior migration was 1.65±0.62 mm (0–9.00), and one loosening case (9.0 mm) was founded. In the loosening case, preoperative radiograph showed the shell had penetrated into the acetabulum. The case had extensive bone defect (4 cm×4 cm) including the medial wall and anterior column.
Summary
The short term result of revision THA with using IBG was reported and most cases showed excellent clinical and radiographic results. But one loosening case was founded. The limitation of IBG may be associated with the lacked bony support behind the graft.
