The PBS Score – a clinical assessment tool for the ambulatory and recurrent clubfoot

PURPOSE: The signs for clubfoot relapse are poorly defined in the literature and there is a lack of a scoring system that allows assessment of clubfeet in ambulatory children. The aim of this study is to develop an easy to use, reliable and validated evaluation tool for ambulatory children with a history of clubfoot. METHODS: A total of 52 feet (26 children, 41 clubfeet, 11 unaffected feet) were assessed. Three surgeons used the seven-item PBS Score to rate hindfoot varus, standing and walking supination, early heel rise, active/passive ankle dorsiflexion and subtalar abduction blinded to the other examiners. All parents answered the modified Roye score questionnaire prior to the clinical assessment. Correlation between the mean PBS Score and the Roye score was evaluated using Spearman’s rank correlation coefficient. Interobserver reliability was tested using weighted and unweighted Cohen’s Kappa coefficients. RESULTS: The Spearman’s rank correlation coefficient for correlation between mean PBS Score and Roye score was 0.73 (moderate to good correlation).The interobserver agreement for the total PBS Score resulted in an intraclass correlation coefficient of 0.93 (almost perfect agreement). CONCLUSION: The PBS score is an easy to use, clinical assessment tool for walking age children with clubfoot deformity. It includes passive and active criteria with a very good interobserver reliability and moderate to good validity. LEVEL OF EVIDENCE: Level I - Diagnostic study