Abstract
Purpose
The incidence of hip displacement in children with cerebral palsy is approximately 30% in large population based studies. The purpose of this study was to report the long-term effect of hip surgery on the incidence of hip displacement using a newly validated Cerebral Palsy (CP) hip classification.
Method
Retrospectively, a sub-group of 100 children who underwent surgery for hip displacement were identified from a large-population based cohort of children born with CP between January 1990 and December 1992. These children were followed to skeletal maturity and closure of their tri-radiate cartilage. All patients returned at maturity for clinical and radiographic examination, while caregivers completed the disease specific quality of life assessments. Patients were grouped according to motor disorder, topographical distribution and GMFCS. Radiographs were independently graded according to CP hip classification scheme to ensure reliability. Surgical Failures were defined as CP Grade > IV.
Results
Ninety-seven children and 194 hips were available for final review. According to GMFCS, greater than half the children were GMFCS IV and V (67/94, 67%), 12 were II and 18 were III. Fifteen hips were dislocated or had salvage surgery for dislocation (15/194, 7.7%) at time of skeletal maturity. The majority of hips were graded Grade II and III (149/194, 76.8%). A total of 39 (39/194, 20%) hips were classified as surgical failure with 95% (37/39) hips occurring in GMFCS IV and V children.
Conclusion
Using the CP hip classification scheme, the natural history and outcome of 100 children with CP at skeletal maturity have been described. Despite hip surveillance and surgical intervention GMFCS IV and V children are at the greatest risk for surgical failure at skeletal maturity. In this study, the majority of failures were associated with either no hip surveillance and/or index surgery at a non-specialist centre. In contrast, hip surveillance and index surgery at a specialist tertiary centre was associated with a very high probability of a successful outcome. This is the first population based cohort study of children with cerebral palsy followed from index surgery to skeletal maturity for hip displacement. Surgical success rates for the treatment of hip displacement in children with cerebral palsy have not previously been reported. This information will aid surgeons in the treatment of hip displacement in children with cerebral palsy.
