Radiological assessment of congenital talipes equinovarus (clubfoot): Is it worthwhile?

The lack in consensus with regard to qualitative use of standard radiographs and their predictive value in evaluating congenital talipes equinovarus among infants continues to be apparent in clinical practice. Since standard radiographs continue to play a role in the assessment of clubfoot it is essential to ensure that the values measured are reliable and reproducible keeping in mind acceptable tolerances for clinical application. This study was undertaken to assess the inter-observer and the intra-observer reliability in estimation of talocalcaneal and talo-first metatarsal angles on standard radiographs done according to Simon's method. The study was conducted by consecutively selecting eleven children with unilateral idiopathic congenital clubfoot who presented to our tertiary care hospital with a paediatric orthopaedic service unit. Only those with unilateral idiopathic clubfoot with persistent deformity at the age of 3 months were included. The data obtained from three observers on two separate occasions was analysed by the method proposed by Bland and Altman to assess intra and inter observer variability in the measurements. The results of the present study suggest a significant difference between the measurements on two occasions by the same observer. The difference was constant and the level of experience of the observer had no significance. Also, there was a marked inter observer variability as evident from the calculation of limit of agreement. Therefore, radiological assessment of the type and degree of malalignment in these cases is insufficient as it does not possess the accuracy required in evaluation and further management.