Evaluation of foot bimalleolar angle in the management of congenital talipes equinovarus.

ABSTRACT

The study was undertaken to establish the normal foot bimalleolar (FBM) angle in Indian infants and to correlate it with the severity of deformity and results of treatment in congenital talipes equinovarus (CTEV). Foot tracings with the level of both the malleoli of 182 feet (91 normal Indian infants) were taken. The anteromedial angle between the long axis of foot and the bimalleolar plane was taken as the FBM angle. The FBM angle in normal infants was calculated as 82.5 degrees. Eighty-four CTEV (51 patients) were clinically classified as grade I (five feet; FBM angle, 73.2 degrees), grade II (21 feet; FBM angle, 66.6 degrees), and grade III (58 feet; FBM angle, 54.7 degrees), depending on whether the foot could be passively corrected (grade I) or had a fixed equinus and/or varus of <20 degrees (grade II) or >20 degrees (grade III). Thirty-one feet (22 patients) were followed up prospectively after conservative (17 feet grade I, three feet; grade II, three feet; grade III, 11 feet) and surgical release (all grade III, 14 feet). All feet with grade I and grade II deformity and 44% (11 feet) with grade III deformity were amenable to gentle graduated manipulations and cast application, whereas 56% (14 feet) with grade III deformity underwent soft tissue release. After nonsurgical treatment, the mean FBM angle was 82.3 degrees. Of the feet that underwent surgery, those with excellent (11 feet) and good correction (3 feet) had a mean FBM angle of 79.9 degrees and 74.3 degrees, respectively. There were no feet with fair or poor results. The clinical severity of foot deformity and results of treatment correlated well with the FBM angle. Foot tracing with the FBM angle is a simple, objective, and reproducible clinical criterion to classify the severity of foot deformity and evaluate the results of treatment.