Study of acetabular index before and after salter innominate osteotomy

Objective: to evaluate pre and post acetabular index in patients with developmental dysplasia of hip whom underwent salter innominate osteotomy. methodology: this cross sectional study was carried out on patients with cdh that underwent salter innominate osteotomy. all cases with cdh admitted in imam khomeini and razi hospitals from november 2007 to august 2009 were included. age, sex, number of involved limb, and affected side were recorded. antero-posterior (ap) roentgenogram were done and acetabular index were calculated before and after surgery. five months later after surgery, ap roentgenogram were obtained from cases and acetabular index were calculated again. before and after surgery acetabular index were compared for each cases. dislocation of hip and avascular necrosis occurrence and grading were assessed for each case. dislocation rate were assessed based on proposed criteria by author from 0 to 4. this criteria was based on percentage of head of femur, which was not covered by acetabulum. our classification is as follows: grade 0: no dislocation; grade i: 30% subluxation; grade ii: 30-60% subluxation grade iii: 60-90% subluxation; grade iv: complete dislocation. results: during two year period of the study, fourteen cdh patients were operated. from these cases, four hips were excluded because the patients did not come for follow up. pre operative acetabular index was 34.40±1.22 and post operative acetabular index was 19.20±1.22. there was significant difference among pre- and post- acetabular index. conclusion: this study showed that there was significant difference among pre and post operative acetabular index. our limitations in this study were low sample size and short duration of follow-up. another prospective study with more sample and long duration is recommended.