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Prediction of hip displacement in children with cerebral palsy: development of the CPUP hip score
M Hermanson1, G Hägglund2, J Riad3
1Lund University, Östra Sjukhuset, Surgery, S-416 85 Göteborg, Sweden.
Insights
A new risk score accurately predicts hip displacement in children with cerebral palsy (CP). This tool helps identify high-risk individuals, guiding further follow-up and treatment decisions for this common CP complication.
Area of Science:
- Orthopedics
- Pediatric Neurology
- Rehabilitation Medicine
Background:
- Hip displacement is a frequent and disabling complication in children with cerebral palsy (CP).
- Early identification of risk factors is crucial for timely intervention and management.
- The CPUP hip surveillance program collects data on children with CP in Sweden.
Purpose of the Study:
- To analyze the risk factors for developing hip displacement in children with CP.
- To develop and validate a predictive risk score for hip displacement.
- To evaluate the score's ability to differentiate between high- and low-risk individuals.
Main Methods:
- Prospective study analyzing data from the CPUP database (children born 1994-2009, GMFCS III-V).
- Calculated odds ratios for hip displacement based on GMFCS level, age, initial migration percentage (MP), and head-shaft angle.
- Constructed a risk score using multiple logistic regression and evaluated its predictive ability (AUC).
Main Results:
- All analyzed variables (GMFCS, age, initial MP, head-shaft angle) significantly impacted hip displacement risk.
- The developed CPUP hip score demonstrated high discriminatory accuracy (AUC = 0.87).
- The score effectively differentiates individuals at high risk for hip displacement.
Conclusions:
- The CPUP hip score is a valuable tool for predicting hip displacement in children with CP.
- This score can aid clinicians in making informed decisions regarding follow-up and treatment strategies.
- Improved risk stratification may lead to better management of hip complications in CP.
Abstract:
Hip displacement, defined in this study as a migration percentage (MP) of more than 40%, is a common, debilitating complication of cerebral palsy (CP). In this prospective study we analysed the risk of developing hip displacement within five years of the first pelvic radiograph. All children with CP in southern and western Sweden are invited to register in the hip surveillance programme CPUP. Inclusion criteria for the two groups in this study were children from the CPUP database born between 1994 and 2009 with Gross Motor Function Classification System (GMFCS) III to V. Group 1 included children who developed hip displacement, group 2 included children who did not develop hip displacement over a minimum follow-up of five years. A total of 145 children were included with a mean age at their initial pelvic radiograph of 3.5 years (0.6 to 9.7). The odds ratio for hip displacement was calculated for GMFCS-level, age and initial MP and head-shaft angle. A risk score was constructed with these variables using multiple logistic regression analysis. The predictive ability of the risk score was evaluated using the area under the receiver operating characteristics curve (AUC). All variables had a significant effect on the risk of a MP > 40%. The discriminatory accuracy of the CPUP hip score is high (AUC = 0.87), indicating a high ability to differentiate between high- and low-risk individuals for hip displacement. The CPUP hip score may be useful in deciding on further follow-up and treatment in children with CP.
