The hallucal interphalangeal sesamoid.

The hallucal interphalangeal sesamoid is considered by some to represent an anatomical rarity that possesses little clinical significance. However, the location of this seemingly innocuous sesamoid bone directly inferior to the hallucal interphalangeal joint of the hallux is associated with the development of several important anatomical, biomechanical, and clinical pathologies. The authors present a review of the literature regarding the location, shape, ontogeny, and surgical management of the hallucal interphalangeal sesamoid. Additionally, the authors discuss the detrimental effect the hallucal interphalangeal sesamoid has on the biomechanical functions of the first metatarsophalangeal and hallucal interphalangeal joints.