Cemented total hip arthroplasty with subtrochanteric femoral shortening transverse osteotomy for severely dislocated hips: outcome with a 3- to 10-year follow-up period.

BACKGROUND: Total hip arthroplasty (THA) for the treatment of severe dislocation of the hip is a technically demanding procedure. In most previous reports, techniques and clinical outcomes using cementless prostheses are widely reported, but there have been few reports on the technique and outcomes using cemented prostheses. The purpose of this study was to evaluate the outcomes of a cemented THA with a simultaneous subtrochanteric femoral shortening transverse osteotomy in patients with Crowe type III or IV developmental dysplasia of the hip.

METHODS: We retrospectively reviewed 15 hips in 11 patients who underwent cemented THA with subtrochanteric femoral shortening transverse osteotomy and with placement of the acetabular component at the level of the anatomic hip center. Patients were evaluated preoperatively and postoperatively with the Merle d'Aubigné and Postel hip score. Radiographic examination was performed to evaluate the level of the femoral osteotomy site, of the radiographic leg lengthening, and of bone union.

RESULTS: The clinical evaluation by the Merle d'Aubigné and Postel hip score was improved from 8.1 ± 2.5 preoperatively to 15.1 ± 1.3 at the time of final follow-up. Radiographic evidence of bone union at the osteotomy site appeared at more than 6 months after operation. Moreover, there were 3 (20%) nonunions that needed reoperation. No acetabular and femoral components exhibited radiological loosening at the time of final follow-up. In addition, one delayed union causing thigh pain was treated with low-intensity pulsed ultrasound that accelerated bone formation.

CONCLUSION: Our results in this study indicate that we should prevent instability at the transverse osteotomy site and an adequate intercalary cortical bone graft is needed to prevent nonunion in cemented THA combined with a subtrochanteric femoral shortening transverse osteotomy. We should apply this procedure with caution in patients, especially those who show less potential bone formation activity.