Analysis and planning of correction of midfoot deformity located in sagittal plane of X-ray

Abstract

OBJECTIVE. The authors developed a new method of assessment and planning of correction of sagittal midfoot deformity, which is based on original reference lines and angles. MATERIAL AND METHODS. X-ray lateral foot projections without deformities were analyzed in 64 adult volunteers. There was determined the angle between articular line of talus trochlea joint and the first metatarsal mechanical axis. It was estimated the ratio of segment length which was limited by distal point of the head of first metatarsal bone and distal edge of articular surface of talus trochlea joint (AC) to segment length, which was limited by edge of articular line of talus trochlea joint (AB). RESULTS. The target angle was 23,6 ± 3,2. The ratio coefficient of segment length AC to AB consisted of 4,3 ± 0,9. The method of planned foot correction was based on data obtained. It allowed doctors to determine the deformity apex and normal position of the first metatarsal head. CONCLUSIONS. The developed method facilitates to plan surgical correction of midfoot deformity in sagittal plane. It gives an opportunity to assess correction results independently from presence of equinus foot position in ankle joint and (or) hindfoot deformity.