Relating to or involving both the astragalus (talus) bone and the navicular bone of the foot.
From astragalus (ankle bone) plus navicular (boat-shaped bone of the foot, from Latin 'navis', ship) plus -ar, describing their anatomical relationship.
The navicular bone is literally named because it's shaped like a little boat (navis = ship)—medical vocabulary is full of these shape-based names that make anatomy easier to remember!
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