CEMENTLESS TOTAL HIP-ARTHROPLASTY IN PATIENTS WITH STEROID-INDUCED AVASCULAR NECROSIS OF THE HIP - A 62-MONTH FOLLOW-UP-STUDY

Twenty cementless porous-coated primary total hip arthroplasties (THA) were performed on 15 patients, all of whom were diagnosed with steroi d-induced avascular necrosis (AVN). The average age of the patients at the time of surgery was 35 years. Minimum follow-up period for all pa tients was 24 months (average follow-up period: 62 months). Patients w ere rated using the modified Harris hip score, as well as serial radio graphs. The average hip score at follow-up examination was 88, with 17 of the 20 hips having good or excellent clinical results. No revision s of the prostheses were performed. Using radiographic criteria, 12 fe moral components met the criteria for bone ingrowth, seven were consid ered stable with fibrous fixation, and one femoral component was loose . When good initial femoral component fit was achieved, bone ingrowth reliably followed. Three acetabular components showed migration on ser ial radiographs. A high rate of acetabular component wear and osteolys is was noted. Avascular necrosis has been shown to adversely affect th e outcome of hip arthroplasty surgery. Previous studies of patients wi th advanced AVN undergoing cemented THA report a high incidence of com ponent loosening. Literature on the results of cementless THA in this patient group is sparse. The study demonstrates encouraging clinical r esults for cementless THA in steroid-induced AVN. Reliable femoral com ponent fixation occurred if a good initial component fit was achieved; however, long-term acetabular loosening and wear remain serious conce rns.