Background: Total hip replacement (THR) is at present an accepted treatment in patients with severe osteoarthritis of the hip after Perthes disease. The aim of this paper is to evaluate the results of THR in patients suffering from secondary osteoarthritis, operated from 1990 to 2000 in the Orthopaedic and Traumatologic Department of Poznan University of Medical Sciences.
Material: Material included 9 patients, 3 females and 6 males, on whom 9 THR were performed, lateral approach was used in all cases. At the time of operation, the age of patients ranged from 41 to 69 years (mean 56). Follow-up ranged from 11 to 21 years (mean 15 years). Cemented total hip arthroplasty was used during 3 of the THR, 6 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 34, WOMAC score 77. After an average of 15-years follow-up all hips were considered excellent, with average Harris score of 93, 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 22-45 degrees (mean: 33 degrees) and the acetabular opening angle was 0-15 degrees (mean: 3 degrees). The stem was neutral-oriented in all 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 Perthes disease 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 Perthes disease in the childhood.