Effect of the Sharrard procedure on hip instability in children with down syndrome: A retrospective study

Abstract

Purpose The aim of this study was to retrospectively analyze the effect of the Sharrard procedure on hip instability in chil- dren with Down syndrome (DS), as measured by the migra- tion index. Methods In total, 17 children (21 hips) were included from six hospitals in the Netherlands between 2003 and 2019. The primary outcome, hip instability, was assessed with the Re- imers’ migration index on preoperative and postoperative plain anteroposterior pelvic radiographs. The mean age at surgery was 8.1 years, the majority of children were male (64.7%) and the mean follow-up time was 7.3 years. Results The mean preoperative migration index was 46% (sd 23.5) and the mean postoperative migration index was 37% (sd 28.4). The mean Delta migration index (the difference in pre-operative migration index and most recent post-opera- tive migration index) showed an improvement of 9.3% (sd 22.7). An improvement in migration index was observed in 52%, no change in 29% and deterioration in 19% of hips. No (re)dislocations occurred in 91% of the hips. No major com- plications were observed during the follow-up period. Conclusion Early intervention is warranted in children with DS showing hip instability or hip migration, in order to suc- ceed with less complex procedures. The Sharrard procedure should be considered in children with DS showing hip insta- bility or hip migration, since it aims to rebalance the muscles of the hip joint, is less complex than bony procedures of the femur and acetabulum, surgery time is often shorter, there are fewer major complications and the rehabilitation period is shorter.