Correlations between physical and ultrasound findings in congenital clubfoot at birth

Background: At birth, clinical classifications are the only available tools for evaluating the severity of congenital clubfoot. Ultrasound provides an assessment of the anatomical abnormalities. The objective of this study was to assess correlations between physical and ultrasound findings at birth.

Hypothesis: Physical and ultrasonography provide different findings in congenital clubfoot and should therefore be used in conjunction.

Material and method: One hundred and forty-five clubfeet in 108 patients born between 2006 and 2010 were included in a retrospective study. Clubfoot severity was classified using two methods, the modified Dimeglio classification based on physical findings and an ultrasound score based on the talo-navicular angle (TNA) and metaphyso-talo-calcaneal angle (MTCA). Each of these two methods distinguished three severity grades. Agreement between the two methods was assessed by computing the coefficient.

Results: The results confirmed the hypothesis by showing low agreement between the clinical and ultrasound classifications. The severity grades were identical with the two methods for only 83/145 (57%) feet. The coefficient was 0.086.

Discussion: The two ultrasound views used to measure the TNA and MTCA, respectively, added an assessment of the three main deformities that characterise congenital clubfoot (equinus, adduction of the forefoot, and adduction of the calcaneo-pedal unit). Ultrasonography complements the physical examination at birth. In the future, using both physical examination and ultrasound scanning to monitor babies with clubfoot may allow early treatment adjustments aimed at optimising the outcome.

Level of evidence: IV, retrospective observational study.