Abstract
Aim Although converting a loosened fixation of the proximal femur into a total hip arthroplasty restores the joint, it is a technically complex operation and often requires steps that are not usually performed in arthroplasty for common diseases. The aim of this study was to assess clinical and radiographic results of 127 total hip arthroplasties due to loosening of proximal femur fixation, performed at our institute.
Materials and methods From 1987 to 2001 we performed 127 total hip arthroplasties (THA) in patients with loosened facture fixation of the proximal femur. Patients treated by endoprosthesis were excluded from this study.
The patients were divided into two groups according to the fracture site. Group 1 included 71 patients with medial fracture, and Group 2 contained 56 patients pertrochanteric or subtrochanteric fracture. All patients were assessed by the Merle d’Aubignè clinical evaluation method. Radiographically, the bone-implant interface was assessed by the presence of radiolucency lines according to the DeLee-Charnley method modified by Martell
Results The mean time lapse between fixation and conversion was 31 months for Group 1 and 10 months for Group 2 patients. In 12 cases of Group 2 bone grafts were used and surgery time was on average 20′ longer than that of Group 1. Furthermore, in Group 2, we had 4 dislocations compared to none in Group 1. In Group 2 long-stem prostheses with diaphyseal conical anchorage were more frequently used, whereas in Group 1 standard prostheses were used in all cases. Patients of Group 2 had a lower clinical score for the three parameters assessed (pain, walking and ROM) than those of Group 1. The final clinical results were also better for Group 1 patients.
Conclusions This study shows how THA in fixation loosening of proximal femur fractures can provide good results. Especially in patients with medial fractures of the femur, since the anatomy is not altered, THA does not pose any particular difficulties and ensures excellent results. In fractures of the trochanteric mass, where non-union or malunion alter markedly the anatomy of the bone segment, the site for the implant, results are certainly inferior However, careful planning of the operation, the use of special prostheses, and bone grafts enable satisfactory results to be achieved in these patients too.
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
