Apophysis of the proximal 5th metatarsal

Last revised by Bahman Rasuli on 29 Dec 2022

The apophysis of the proximal 5th metatarsal (plural apophyses) lies laterally and is oriented longitudinally parallel to the shaft.

Apophysis of the fifth metatarsal base appears on plain radiographs at age 12 years for boys and 10 years for girls. Fusion of the apophysis to the metatarsal base usually occurs within the following 2-4 years 3,4.

Differential diagnosis

It should not be confused with an os peroneum or an avulsion fracture. An avulsion fracture at this location is typically extra-articular and oriented transversally as compared to the longitudinal orientation of an unfused apophysis.

Related pathology

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