[Medium-term results of the cementless femoral neck prosthesis CUT].

AIM The present work aims at evaluating the clinical and radiological midterm results of the femoral neck prosthesis CUT. METHOD 67 femoral neck prostheses of the type CUT were implanted in 63 patients between 4/1999 and 5/2003 (average age 56 years). At an average follow-up time of 5.1 years (min.: 2.9; max.: 6.9) 53 patients with 57 CUT prostheses were examined clinically with the Harris hip score and radiologically. All together we determined the state of 64 CUT prostheses (96%). RESULTS The mean Harris hip score improved from 55 points preoperatively to 90.4 points at the last follow-up and is assessed as a good result. A total of 7 CUT prostheses (11%) had been revised. 3 CUT prostheses (4.7%) had been revised because of aseptic loosening, 2 (3.1%) because of persisting postoperative thigh pain, 1 (1.6%) because of vertical migration of an unsuitable CUT prostheses a few days after the operation and 1 (1.6%) because of septic loosening. The survival rate according to Kaplan-Meier was 89.1% at 5.1 years. If the femoral neck was resected too widely there was an increased rate of horizontal migration with aseptic loosening of the CUT prostheses. CONCLUSION In the midterm follow-up the CUT prosthesis shows a higher loosening rate as compared with cementless standard stems.