Imaging of tarsal navicular disorders: a pictorial review.

The tarsal navicular is a bone within the midfoot that plays a critical role in maintaining the arch of the foot. This bone is clinically relevant because it may be affected by a wide array of pathologies. Our approach includes a detailed description of the imaging characteristics and disorders affecting the tarsal navicular. Organization includes (a) normal imaging, (b) accessory ossicles, (c) coalition, (d) fractures, (e) Kohler's disease, (f) osteonecrosis, (g) osteochondral lesions, (h) arthropathies, and (i) tumors. The purpose of this article is to discuss normal variants and pathological processes that can affect the tarsal navicular, with emphasis on the often-overlooked imaging findings.