Outcome of Open Hip Reduction, Pelvic Osteotomy, and Varus Derotational Osteotomy in Children With Cerebral Palsy: A Retrospective Study

Introduction: For spastic hip dislocations, a variety of operations are available with open hip reduction and varus derotational osteotomy of the proximal femur combined with pelvic osteotomy +/- adductor release being a good option with favourable outcomes. This study aims to assess the outcome and complications of combined open hip reduction with pelvic osteotomy and varus derotational osteotomy. Methods: In this study, 70 hips in 52 patients with spastic hip dislocation due to cerebral palsy were included. All included patients were treated surgically in our institute between January 2016 and December 2021. There were 31 males and 21 females. For each patient, information was collected about the age at the time of surgery and different radiological parameters at three different time intervals: pre -operatively, immediately post -operatively, and at the final follow-up. We also collected information about any complications arising from the surgery performed. Results: The mean duration of follow-up was 19.58 months. The acetabular index decreased from an average of 35.01(degrees) to 17.18(degrees) with a mean difference of 17.83(degrees )(p<0.001). The central edge angle, which averaged -49.13(degrees) in the pre -operative period, increased to 26.34(degrees) and then marginally decreased to 25.47(degrees) at the final followup. The average migration index of 80.51% in the pre -operative period improved to 1.4% post -operatively with a mean difference of -79.11% (p<0.01). The migration index increased to 8.54% at the final follow-up. Similarly, the neck -shaft angle, which averaged 160.89(degrees) in the pre -operative period, decreased to 125.23(degrees) at the time of final follow-up with a percentage change of -22.16%. Conclusion: Single -stage combined surgery in the form of combined open hip reduction and pelvic osteotomy with varus derotational osteotomy successfully treats the condition and shows good outcomes in patients with spastic hip dislocations. This treatment is associated with very few complications.