Abstract
Introduction: We performed cementless total hip arthroplasty (THA) with autogenous bone block grafting on 18 hips in 15 patients with marked acetabular dysplasia and investigated the correlations of clinical results with the placement of the acetabular and femoral components.
Methods: There were 13 women and 2 men who had a mean duration of follow-up of 3.3 years (range, 2 to 4.3 years). According to the classification of Crowe et al, four hips in group I, three hips in group II, one hip in group III and 10 hips in group IV. The resected femoral head was used as a graft for the superior-lateral region of the true acetabulum.
Clinical results were determined according to the hip joint function criteria of the Japanese Orthopaedic Association (JOA).
Results: The mean preoperative JOA hip score was 44 points and that at follow up was 77 points. The distance from the Kohler line to the medial margin of the acetabu-lar component averaged 6.1 mm on the radiograph. Two patients required revision. In both patients, lateral insertion of the acetabular component of 8 and 15 mm respectively from the Kohler line had resulted in loosening of the cup. Of the 18 patients, femoral component had been placed in neutral position in 9, who had better clinical results than those of the others. The grafted bones united in all patients.
Discussion: The present study indicates that lateral insertion of the the acetabular component in THA should be avoided in patients with marked acetabular dysplasia.
The abstracts were prepared by Nico Verdonschot. Correspondence should be addressed to him at Orthopaedic Research Laboratory, University Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
