Static rearfoot alignment: a comparison of clinical and radiographic measures

Foot structure is typically evaluated using static clinical and radiographic measures. To date, the literature is devoid of a correlation between rearfoot frontal plane radiographic parameters and clinical measures of alignment. In a repeated-measures study comparing radiographic and clinical rearfoot alignment in 24 healthy subjects, radiographic angular measurements were made from standard weightbearing anteroposterior, lateral, long leg calcaneal axial, and rearfoot alignment views. Clinical measurements were made using a jig and scanner to assess the malleolar valgus index and a goniometer to evaluate the resting and neutral calcaneal stance positions. There was a significant correlation between frontal plane radiographic angles (long leg calcaneal axial and rearfoot alignment views) (r = 0.814). Similarly, there was a significant correlation between clinical measures (resting calcaneal stance position and malleolar valgus index) (r = 0.714). A multivariate stepwise regression showed that resting calcaneal stance position can be accurately predicted from 3 of the 15 clinical and radiographic measurements collected: malleolar valgus index, rearfoot alignment view, and long leg calcaneal axial view (r = 0.829). In summary, a commonly used clinical measure of static rearfoot alignment, resting calcaneal stance position, was correlated closely with the malleolar valgus index and both frontal plane radiographic parameters.