Prevalence and Risk Factors for Leg Length Discrepancy in Children With Idiopathic Clubfoot Treated With Ponseti Method

Introduction: Clubfoot is at times associated with other lower extremity abnormalities, such as leg length discrepancy (LLD). Initial studies in patients treated with extensive soft tissue release (STR) have estimated that LLD is prevalent in 9% to 11% of children with idiopathic clubfoot. However, Ponseti-style serial casting has since replaced STR as the preferred clubfoot treatment method. This study aimed to assess the prevalence of LLD, risk factors for LLD, and the required treatment in children with clubfoot deformity after Ponseti casting. Methods: A retrospective review of medical records from children ages 0 to 18 treated for clubfoot at a single institution from 2002 to 2023 was conducted. Included patients were initially treated with Ponseti casting and had minimum follow-up until age 3. Patients with nonidiopathic clubfoot or who had LLD noted on physical examination but did not have available radiographs were excluded. LLD was defined as a minimum discrepancy of 0.5 cm on bilateral lower extremity radiographs. Results: Two hundred seventy-eight patients (434 feet) met criteria; 73% (203) were male. Forty of the 49 patients with available radiographs had LLD. The prevalence of LLD was 14.4%, with an average discrepancy of 1.1±0.8 cm. The prevalence was significantly higher in patients with unilateral than bilateral cases, 27% (33) versus 4.5% (7), P=<0.001. LLD was present in 21.5% (32) of patients with recurrence and 6.2% (8) of patients without recurrence, P=<0.001. Twenty percent (8) of patients with LLD had an epiphysiodesis at an average age of 11.5±1.4 years. Conclusion: This study reported a prevalence of LLD in 14.4% of children with idiopathic clubfoot treated with Ponseti casting. LLD prevalence was higher in children with unilateral and recurrent clubfoot. Up to 20% of children with LLD may require an epiphysiodesis. We recommend that care providers regularly screen children with clubfoot for LLD, particularly those with unilateral and recurrent deformities, and consider obtaining bilateral lower extremity radiographs in patients with clinical LLD.