Hallux sesamoid fracture

Hallux sesamoid fractures are the commonest foot sesamoid fractures, with the medial sesamoid fractured more frequently than the lateral one . These hallucal sesamoids are also vulnerable to weight-bearing stress injury .

Radiographic features

A sharp fracture line is seen separating irregular opposing surfaces of the sesamoid fragments. It can be depicted on plain radiograph of the foot with the aid of different projections. Axial hallux sesamoid bone projection may be an additional option for suspected fracture.

CT is more sensitive and specific than plain radiographs. MRI is rarely needed to confirm the diagnosis, however can be used to differentiate this entity from sesamoiditis or other diseases of the hallux sesamoid bones .

Differential diagnosis

The main differential diagnosis is a bipartite sesamoid bone. Well-corticated smooth margins of the bone fragments are a helpful sign of this anatomical variation.