Figure 4.

Characteristics of Haglund deformity as measured on preoperative lateral ankle radiographs. (A) The parallel pitch lines were obtained by drawing the inferior line from the inferior margin of the calcaneocuboid joint to the plantar tuberosity of the calcaneus; the superior line was drawn parallel to the inferior line beginning at the posterior margin of the subtalar joint. If the posterior calcaneal prominence was located above the superior line (arrow), it was considered abnormal and consistent with Haglund deformity. (B) The Haglund deformity height was obtained by drawing a line at the base of the posterosuperior calcaneal prominence and measuring the height of Haglund deformity perpendicular to that line (double-headed arrow). (C) The Chauveaux-Liet angle was measured as (α – β), where α is the inclination angle and β is the posterior angle of the calcaneus. (D) The Fowler-Philip angle was measured between an inferior line that was tangent to the inferior margin of the calcaneocuboid joint and the plantar tuberosity of the calcaneus and a superior line that was tangent to the posterior prominence at the insertion of the Achilles tendon.