Analysis of Whole Limb Alignment in Ankle Arthritis.

A full-length standing posteroanterior radiograph that includes the calcaneus (hip-to-calcaneus radiograph) is obtained for evaluation of the mechanical axis of the entire lower limb in patients with a lower limb condition involving malalignment. Such evaluation clarifies several pathomechanical aspects of hindfoot disorders, facilitates surgical planning, and elucidates factors contributing to unsatisfactory results of a particular operation. Whole limb alignment is influenced not only by the knee joint but also by the ankle joint; thus, knee realignment influences hindfoot alignment and vice versa. It is essential to analyze alignment of the whole limb in planning corrective lower limb surgery.