ABSTRACT
PURPOSE: To evaluate the radiologic changes in the acetabulum after shelf acetabuloplasty in Legg-Calve-Perthes (LCP) disease. MATERIALS AND METHODS: From January 2003 to March 2006, 13 patients with unilateral LCP disease were treated by shelf acetabuloplasty. The mean follow-up period was 51 months. Pre-operative, post-operative, and annual follow-up radiographs were obtained to assess the changes in lateral subluxation ratio (LSR), acetabular head quotient (AHQ), acetabular depth index (ADI), acetabular height index (AHI), total depth index (TDI) and width of bone graft. RESULTS: The mean LSR decreased from 1.78+/-0.32 pre-operatively to 1.48+/-0.15 post-operatively, and remained 1.33+/-0.21 at last follow-up (p=0.011). The mean AHQ increased from 81.0+/-7.5% pre-operatively to 120.0+/-15.1% post-operatively, and remained 109.7+/-13.8% at final follow-up (p=0.001); the post-operative TDI that included the width of bone graft, decreased at follow-up. Furthermore, the mean ADI and AHI changed from 0.97+/-0.12, 1.13+/-0.07 pre-operatively to 1.04+/-0.02, 1.15+/-0.09 post-operatively; last follow-up results were 1.03+/-0.05 and 1.16+/-0.07, respectively. Between the 2 indices, post-operative ADI for 2 years was statistically significant (p<0.05). Also, the width of bone graft decreased from 24.4+/-3.6 mm post-operatively to 15.0+/-4.1 mm at final follow up (p<0.05). CONCLUSION: The indices LSR and AHQ confirmed that the shelf acetabuloplasty could preserve the femoral head containment. The growth of the acetabulum after shelf acetabuloplasty was stimulated by increasing the depth of acetabulum in comparison with height for postoperative 2 years. Further follow-up is needed until skeletal maturity.