Analysis of the results of implantation of total hip endoprothesis in severe dysplastic coxarthrosis.

BACKGROUND The aim of this study is to affirm the importance of operative treatment of severe dysplastic coxarthrosis through analysis of the results of implantation of total cementless endoprothesis in patients with DDH Crowe types III and IV. PATIENTS AND METHODS This retrospective study involved 28 patients (30 hips) with dysplastic coxarthrosis, in whom an implantation of cementless total hip endoprothesis was performed at the University Clinic for Orthopaedic Surgery in Skopje. In 26 of the patients the involvement was unilateral and in two patients it was bilateral. The inclusion criterion was radiographically proved severe hip dysplasia Crowe types III and IV. Twenty-one of the patients were female and 7 male, and age distribution was in an interval from 30 to 65 years. The ingrowth of the implant was evaluated using the clinical method, native radiographs and radioisotopic examination with Tc99m. The follow-up period lasted 5 years, and the results were evaluated using the Harris hip score system. RESULTS 19 of the patients presented an excellent result of the operative treatment, there were 8 good results with persistent local pain 6 months postoperatively, in one case a surgical revision and reimplantation of the acetabular cup was performed, while one patient underwent a surgical revision and reimplantation of the femoral stem and in another patient there was nonunion at the place of the subtrochanteric osteotomy. Full weight-bearing without the use of crutches was achieved 3 months postoperatively, and no serious early postoperative complications were registered in our patients. DISCUSSION AND CONCLUSIONS In the majority of cases in whom a total hip replacement with cementless endoprothesis is performed because of dysplastic coxarthrosis, a sufficient primary fixation both of the acetabular and the femoral component is achieved, unless one-third of the acetabular cup is left uncovered with bone stock. The problems of decreased muscle strength and limping are usually solved by means of physical therapy in a time period of 45 months.