Modular Cementless Total Hip Arthroplasty with Subtrochanteric Shortening Osteotomy in Patients with High Hip Dislocation

PURPOSE: The purpose of this study was to report on the results of performing modular cementless total hip arthroplasty with a simultaneous subtrochanteric shortening osteotomy in patients with high hip dislocation. MATERIALS AND METHODS: We evaluated 23 patients (24 hips) with high hip dislocation and who had undergone total hip arthroplasty using a proximally modular cementless stem in combination with a subtrochanteric shortening osteotomy in order to place the acetabular cup at the level of the anatomic hip center between May 1996 and June 2008. There were 6 males and 17 females with a mean age of 44 years. The mean duration of follow-up was 5.6 years. RESULTS: The mean Harris hip score improved from 53 points preoperatively to 88 points at the time of final follow-up (P<0.001), and there were good or excellent results in 21 hips (87.5%). There was one instance of isolated loosening of the acetabular component. With the exception of one hip requiring revision surgery at 12 years postoperatively because of polyethylene wear and cup loosening, all the remaining components were well-fixed at the time of the last follow-up. A total of 4 hips (17%) had complications during follow-up; one dislocation, two transient femoral nerve palsies and one nonunion of the subtrochanteric osteotomy site. CONCLUSION: Modular cementless total hip arthroplasty with a subtrochanteric shortening osteotomy in patients with high hip dislocation was associated with excellent clinical outcomes while it minimized additional fixation of the osteotomy site.

A Modular Cementless Femoral Prosthesis for Revision HipArthroplasty

Purpose: The goal of study was to evaluate the clinical and radiographic performance of the proximal modular cementless femoral stem for use in revision total hip arthroplasty. Material and method: Fifty seven patients (57 hips) were followed for longer than 24 months or up to 8.4 years after performing revision total hip arthroplasty with using the proximal modular cementless femoral stem between January 1997 and December 2002. The preoperative diagnosis included 45 cases of aseptic loosening, 5 cases of septic loosening (re-revision operation), 6 cases of periprosthetic fracture and 1 case of recurrent dislocation. The bone deficiencies were classified according to the Paprosky classification: there were 27 cases of Type I and II, 19 cases of Type IIIA, 9 cases of Type IIIB and 2 cases of Type IV. Results: The average Harris hip score improved from 47 to 87.6. Clinically satisfactory results were noted in 50 patients (87.7%). Radiographically, distal stable fixation was observed in 54 patients (94.7%). Intraoperative complications included two greater trochanteric fractures and two proximal femur fractures. Postoperative complications included 5 femoral stem subsidences (2hips20mm), 4 deep infections, 2 non-unions of the greater trochanter and the osteotomy site and set screw dissociation was noted in 1 case. 5 proximal component changes were done due to progressive subsidence in two cases, non-union at the osteotomy site and trochanteric displacement in two cases and set screw dissociation in one hip. For the infection cases, the proximal segment was removed and re-revised with a 2nd stage operation. (Ed note: check this.) The subsidence of the femoral stems was showed in 3 Paprosky grade IIIA cases and in 2 cases of grade IIIB or more. There was no postoperative periprosthetic fracture observed at the last follow-up. Conclusion: Revision total hip arthroplasty using the proximal modular cementless femoral stem showed good results in the face of the infection of the proximal component and deficient proximal bony support. This procedure appears to be convenient for the surgeon to correct anteversion of the femoral head and leg length discrepancy.