Hospitalizations Following Complex Hip Surgery in Children with Intellectual Disability: A Self-Controlled Case Series Analysis

Objective: To evaluate the associations between complex hip surgery and subsequent hospitalizations in children with intellectual disability, including a subset of children with cerebral palsy. Study design: We conducted a retrospective cohort study using linked administrative, health, and disability data from Western Australia. Children born between 1983 and 2009 who underwent complex hip surgery by end 2014 were included (intellectual disability, n = 154; subset with cerebral palsy, n = 91). A self-controlled case series analysis using Poisson regression was used to estimate the age-adjusted associations of complex hip surgery on all-cause hospitalizations and when the principal diagnosis was lower respiratory tract infection or epilepsy, for periods following the individual's first major hip surgery, compared with the year before surgery. Results: Age adjusted incidence of all-cause hospitalizations decreased after surgery (year 1: incidence rate ratio [IRR] 0.87 [95% CI, 0.74-1.02]; year 6: IRR 0.57 [95% CI, 0.46-0.72]). The incidence of hospitalizations for lower respiratory tract infection increased (year 1: IRR, 1.03 [95% CI, 0.72-1.51]; year 6: IRR 2.08 [95% CI, 1.18-3.68]). The incidence of hospitalizations for epilepsy decreased (year 1: IRR 0.93 [95% CI, 0.57, 1.54]; year>6: IRR 0.72 [95% CI, 0.34-1.55]) after surgery. A similar pattern was observed for the subset of children with or without cerebral palsy. Conclusion: Complex hip surgeries are associated with fewer hospitalizations overall but not respiratory hospitalizations for children with intellectual disability. Fewer hospitalizations suggest benefits for better musculoskeletal alignment.