measured between a line tracing the inferior border of the calcaneus and the horizontal. θ2: The intersection of the talar axis and the 1st metatarsal axis forms ...
SUPPLEMENTAL FIGURE LEGENDS Supplemental Figure 1 - Measurements for ML view adapted from Spratley et al.46 The axis of the calcaneus is formed by a line passing through the midpoints of the widest points of the anterior and posterior aspects. The talar axis is formed by lines connecting the superior most 5
point on the talar dome to the tip of the lateral process and across the anterior margins of the talar neck; the axis bisects these two lines. The first metatarsal axis is formed by bisecting lines across the width of the proximal and distal diaphysis. θ1: The calcaneal pitch angle (ML-CP) is measured between a line tracing the inferior border of the calcaneus and the horizontal. θ2: The intersection of the talar axis and the 1st metatarsal axis forms the ML talo-1st metatarsal angle
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(ML-T1MT). θ3: The intersection of the talar axis and the calcaneal axis forms the talocalcaneal angle (ML-TC). θ4: The talar declination angle (ML-Tdec) is measured between the talar axis and the horizontal. θ5: Finally, the calcaneal 1st metatarsal angle (ML-C1MT) is measured between the axis of the calcaneus and the 1st metatarsal axis. The heights of the δ1: talar (MLTal-h), δ2: navicular (ML-Nav-h), δ3: first cuneiform (ML-1CN-h), and δ4: cuboid (ML-Cub-h)
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were measured from the inferior most point perpendicular to a line connecting the inferior margin of the calcaneus and that of the medial sesamoid. δ5:The first cuneiform to the fifth metatarsal height (ML-1CN/5MT) was measured from the same inferior most point on the cuboid to the inferior most point on the base of the fifth metatarsal.
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Supplemental Figure 2 - Measurements for standard AP view adapted from Spratley et al. 46
θ6: The talonavicular angle (AP-TN) is measured between the talar and navicular AP axes as
described by Sangeorzan. These axes are defined as the orthogonal projections of lines spanning the medial and lateral margins of the respective articular surfaces. The axes of the first and
second metatarsals are formed in a similar fashion for the AP view as in the ML view wherein 25
the axes bisect lines crossing the proximal and distal widths of the diaphyses. θ7: The talar first metatarsal (AP-T1MT) and θ8: talar second metatarsal angles (AP-T2MT) are formed between the talar axis and the axis of the first and second metatarsals, respectively. δ6: The talonavicular uncoverage distance was measured as the AP distance separating the medial margins of the talar and navicular articular surfaces.
