Clinically Detected Leg Length Discrepancy in Patients With Idiopathic Clubfoot Deformity: Prevalence and Outcomes.

Abstract

This study evaluates the prevalence and outcomes of patients with idiopathic clubfoot and clinically detected limb length discrepancy (LLD). This is a retrospective cohort study of idiopathic clubfoot patients in a Research Ethics Board-approved clubfoot registry. Patients with LLD ≥0.5 cm (LLD+) were compared with those with no or <0.5 cm LLD (LLD-). LLD was determined by documented clinical examination. Exclusion criteria included nonidiopathic clubfoot deformity, <2-year follow-up, and incomplete records. Of the 300 patients included, 27 (9.0%) had an LLD, of whom 23 patients had a unilateral clubfoot deformity. The prevalence of LLD was 15.3% and 2.67% in unilateral and bilateral clubfoot patients, respectively. The mean LLD was 1.21 cm (0.5 to 3.5 cm, SD: 0.78 cm) in LLD+ patients, with a mean of 1.27 cm (SD: 0.79 cm) in unilateral clubfoot patients and 0.88 cm (SD: 0.75 cm) in bilateral patients. The total number of casts applied in LLD+ unilateral clubfoot patients was significantly higher than in LLD- unilateral patients (9.5 vs. 6.8 casts; P =0.015). The overall relapse rate in all patients was 30.3% and was significantly higher in the unilateral only LLD+ group [relative risk (RR)=2.89] and the total LLD+ patient cohort (RR=1.68). The risk of repeat casting for relapse was also higher in the unilateral LLD+ group (RR=2.45) and the total LLD+ group (RR=1.87). The risk of surgery for relapse was significantly higher in the unilateral LLD+ group for any surgery ( P =0.046), and most specifically for open tendo-Achilles tenotomy ( P =0.008) and tibialis anterior tendon transfer ( P =0.019). There was no correlation between the severity of LLD and Pirani score at presentation. LLD was present in 9% of idiopathic clubfoot patients, and most were <2 cm. There is a significantly higher risk of relapse in patients with unilateral clubfoot and LLD. The risk of surgery overall was higher in all patients with a unilateral LLD. Assessment of LLD should be routinely performed in clubfoot patients. Level III.