Effect of pelvic osteotomies which are used in the treatment of developmental dysplasia of the hip on femoral head physis

Objectives: The aim of this study is to assess the effects of Salter's and Pemberton's pelvic osteotomies (SPO, PPO) which are used in the treatment of developmental dysplasia of the hip, on the femoral head physis. Materials and Methods: We made radiological and clinical assessments of 52 patients (69 hips) who were treated with pelvic osteotomy and open reduction, retrospectively between Jan 2008 – Dec 2011. Patients with a previous history of neuromuscular disorder, concomitant anomaly of lower extremity, collagenous tissue disorders, and who were treated for DDH previously were excluded from the study. Results: There were two groups, SPO (n=35) and PPO (n=34). Preoperative and postoperative mean AI angle of PPO group was 36,2°±4,9° and 23,4°±3,9° respectively; meanwhile 35,6°±3,8° and 23,1°±5,1° in the SPO group. Center edge angle was measured for the assessment of acetabular coverage. Mean CE angle was 23,5°±10,4° in the PPO group and 20,6°±11,7° in the SPO group. There was no significant difference in avascular necrosis, AI angles, CE angles between the osteotomy groups. However, postoperative AVN was significantly higher in Tönnis stage 4 hips than Tönnis 1-3 stages. There was no coxa valga, on the other hand 3 coxa vara patients were observed. Conclusion: Despite the theories that PPO had a higher risk than SPO for AVN, both in the literature and in our study there was no statistical difference between osteotomy groups. Especially, the stage of the DDH was seen as a more important risk factor for AVN, independent from the osteotomy. However, further studies on wider groups for a stronger statement are needed. Key words: Pelvic osteotomy, Salter, Pemberton, Femoral head physis