The contralateral foot in children with unilateral clubfoot, is the unaffected side normal?

The unilateral unaffected clubfoot has previously been used as a control in longitudinal studies of clubfoot outcomes. However, we have observed that the unaffected clubfoot does not necessarily exhibit the same pedobarographic measurements as seen in normal control subjects. The purpose of this study was to evaluate whether the unaffected foot is indeed normal or if there are differences in the pedobarographic measurements of the unaffected foot compared to healthy normal controls.The Tekscan HR Mat™ was used to dynamically test the walking pattern of 103 subjects with unilateral clubfeet and compare the results to our previously published series of normal controls. Patients were divided into three groups: Group 1 (< 2 years), Group 2 (2-5 years) and Group 3 (>5 years). An unpaired t-test (p < 0.05) was used to compare percentage of stance at initiation of force, the percentage of stance at maximum force, the percentage of stance at termination of force, the maximum percentage force and the average force/time integral between a group of normal age matched controls and the unaffected foot in patients with unilateral clubfoot. Significant differences were identified between the unaffected side and normal controls for the pressure distribution, order of initial contact and foot contact time. These differences evolved and changed with age. The pedobarographic measurements of patients with clubfoot are not normal for the unaffected foot. As such the unaffected foot should not be referred to as normal, nor should it be used as a control.