[Total hip replacement after slipped capital femoral epiphysis].

Background: Total hip replacement (THR) is at present an accepted treatment in patients with severe osteoarthritis of the hip after slipped capital femoral epiphysis. The aim of this paper is to evaluate the results of THR in patients suffering from secondary osteoarthritis, operated from 1987 to 2004 in the Orthopaedic and Traumatologic Department of Poznan University of Medical Sciences.

Material: Material included 16 patients, 9 females and 7 males, on whom 18 THR were performed, lateral approach was used in all cases. At the time of operation, the age of patients ranged from 32 to 70 years (mean 50). THR was carried out after 33 years afterwards slippage of capital femoral epiphysis. Follow-up ranged from 6 to 23 years (mean 11 years). The operative treatment was a multistage process (during one operation only one joint was replaced). Cemented total hip arthroplasty was used during 5 of the THR, 13 of them were cementless.

Method: The patients were clinically and radiologically evaluated preoperatively, postoperatively, and at final examination. The clinical state was evaluated with Harris hip score and WOMAC scale. We based our radiological examination on Hip Society system.

Results: The average preoperative Harris score for the group of patients was 32, WOMAC score 74. After an average of 11-years follow-up all hips were considered excellent, with average Harris score of 91, WOMAC Score of 6. All patients had increased function and decreased pain. The radiograms of all patients revealed that the acetabular and femoral components were correctly positioned with no radiographic evidence of loosening in the last examination. The inclination angle of the acetabular component was 22-49 degrees (mean: 36 degrees) and the acetabular opening angle was 0-10 degrees (mean: 4 degrees). The stem was valgus-oriented in 1 hip, and neutral-oriented in 17 hips. No ectopic ossification concentrations were found.

Conclusion: . Clinical and radiological evaluation of our material showed that total hip replacement in the treatment of osteoarthritis secondary to slipped capital femoral epiphysis allows regaining good lower limb function, which helps the patients staying less dependant on the surrounding environment. The results of THR are good regardless of the type of prosthesis and the type of fixation. Importantly, THR was carried out after a quite long time after slippage of capital femoral epiphysis.