[CEMENTLESS TOTAL HIP ARTHROPLASTY AND IMPACTED BONE GRAFTING FOR PROTRUSIO ACETABULI IN PATIENTS WITH RHEUMATOID ARTHRITIS].

OBJECTIVE: To evaluate the effectiveness of total hip arthroplasty (THA) with impacted autologous bone grafting and a cementless cup in the treatment of rheumatoid arthritis (RA) with protrusio acetabuli.

METHODS: Between January 2001 and April 2009, 18 cases (20 hips) of RA with protrusio acetabuli were treated, including 6 males and 12 females with an average age of 46 years (range, 36-62 years). The disease duration was 3-10 years (mean, 6 years). Preoperative Harris score was 40.25 ± 6.68. The protrusio acetabuli was (5.70 ± 4.26) mm. According to Sotelo-Garza and Charnley classification criterion, there were 12 hips of type 1 (protrusio acetabuli 1-5 mm), 5 hips of type 2 (6-15 mm), and 3 hips of type 3 (>15 mm). All patients received THA with impacting bone graft and cementless prosthesis for recovery of acetabular center of rotation.

RESULTS: The average operation time was 74 minutes (range, 48-126 minutes); the average blood loss was 350 mL (range, 150-650 mL). Deep venous thrombosis of lower extremity and poor healing of incision occurred in 3 and 2 cases respectively. Other patients achieved primary healing of incisions. The mean time of follow-up was 108 months (range, 60-156 months). According to X-ray films, bone grafting fusion was observed within 6 months after operation. At last follow-up, the Harris score was 87.20 ± 4.21, showing significant difference when compared with preoperative score (t = -27.68, P = 0.00); the protrusio acetabuli was (-1.11 ± 0.45) mm, showing significant difference when compared with preoperative value (t = 5.66, P = 0.00). No loosening of acetabular components was found.

CONCLUSION: For RA patients with protrusio acetabuli, THA with impacted autologous bone grafting and a cementless cup has satisfactory medium-term effectiveness.