Clinical Outcomes of Casting Phase of Ponseti Method for Correction of Idiopathic Talipes Equinovarus at the Kenyatta National Hospital

Abstract

Background: Congenital talipes equinovarus (CTEV) also known as clubfoot, is a common musculoskeletal deformity at birth, affecting about 1-2 babies per 1000 live births, most of whom are born in low and middle-income countries. Treatment modalities for clubfoot involve nonsurgical and/or surgical interventions. Ponseti technique is the preferred intervention for nonsurgical management of clubfoot at Kenyatta National Hospital. Despite the global preference for this treatment technique, there is general paucity of data on clinical outcomes of this procedure in LMIC countries, especially in Sub-Saharan Africa. This study seeks to evaluate the clinical outcomes of the casting phase of the Ponseti method in this setting. Study objective: To evaluate the outcome of the casting phase of the Ponseti method for clubfoot correction at Kenyatta National Hospital (KNH). Study design: A retrospective cross-sectional study. Patients and methods: Records of patients aged 24 months and below diagnosed and treated for idiopathic clubfoot were retrieved. Data was extracted, coded, and entered into the Statistical Package for Social Sciences (SPSS) (IBM Statistics Software Version 26, Armonk, New York, USA) for analysis. Prism 8 (GraphPad Software, San Diego, CA, USA) was used to generate graphs. Categorical data (clubfoot laterality, family history of clubfoot, tenotomy rate and complication rate) were reported as frequencies (%) while continuous data were reported as mean and standard deviation if it was normally distributed (pre-casting Pirani score, post-casting Pirani score and duration of casting), or as median and interquartile range (IQR) for data that was not normally distributed (age). Comparison of continuous outcomes between males and females was performed using the Mann-Whitney U Test (for data that was not normally distributed e.g., age) and the Independent Student’s t-test (for data that was normally distributed). Comparison of categorical variables was performed using the Chi-square 2 statistic. Pearson’s test was used to for correlation of continuous variables. Throughout the analysis, a p-value of <0.05 was considered significant at a 95% confidence interval. The results are presented as tables and graphs. Results: A total of 68 records were retrieved. Only 63 had complete data and were therefore included in the final analysis. The median age at time of diagnosis was 0.46 months (IQR 0.2-1.5), and majority of them were males (M:F ratio 1.74:1). Slightly more than half of the patients had bilateral CTEV (50.8%), and a quarter (25.4%) had a positive family history. The mean pre-casting Pirani score was 3.8±1.8. The mean duration of Ponseti casting was 4.5 weeks (SD=1.9), and it positively correlated with age (p=0.026) and pre-casting score (p<0.001). The mean Ponseti score significantly reduced following casting phase from 3.7±1.8 (pre-casting score) to 0.2±0.7 (post-casting score) (mean difference= 3.5, p<0.001). The post-casting Ponseti score positively correlated with age (p<0.001). Tenotomy was performed in 14 patients (22.2%) after casting. Patients requiring a tenotomy tended to be older (3.3±4.7 vs 0.7±0.9 weeks; p<0.001) and had a higher pre-casting Pirani score (4.8±1.7 vs 3.5±1.7, p=0.006). A total of 6 patients (9.5%) developed complications following Ponseti casting. These complications included limb swelling (4 cases) and cast sore (2 patients). Conclusion: Ponseti casting is an effective treatment technique for congenital talipes equinovarus, with minimal complication rate.