A Radiographic Technique for the Assessment of Ankle and Midfoot Equinus

Abstract

Background: Both clinical and radiographic techniques have been used to evaluate foot and ankle position and orientation. Clinical measurements have been shown to be less reliable than radiographic measurements. Because midfoot equinus deformity may coexist with ankle joint equinus deformity, a radiographic method of separating and measuring these two components is desirable. The purpose of this study was to evaluate a new radiographic technique, the Lateral Mid-Tibia to Toes (LMTT), weightbearing view of the foot and ankle. Method: Twenty LMTT images were randomly selected from the study population of patients treated in our center for lower limb equinus deformity. Validation was achieved by a study involving three observers, assessing 20 images on two consecutive occasions, 4 weeks apart. Analysis was performed using Kappa statistics. Results: The plantigrade and midfoot equinus angles provided substantial (p = 0.000) and moderate (p = 0.005) agreement, respectively. Conclusions: Awareness of midfoot equinus and its correction may avoid residual deformity when surgery is performed to correct equinus deformity of the ankle.