Fifth metatarsal fractures are not all the same: proximal diaphyseal fractures are prone to delayed healing

Abstract

This paper is designed to be a guide to the classification and treatment of fifth metatarsal fractures. Types of fifth metatarsal fracture include: avulsion fracture of the tuberosity, proximal diaphyseal (Jones) fracture, proximal diaphyseal stress fracture, diaphyseal (shaft) fracture, and fractures of the neck and head. Diagnosis of these fractures can be made with a sound anatomical knowledge, identification of the mechanism of injury and previous symptoms, as well as appropriate X-ray examination. Confusion with diagnosis may occur due to the similarity of the proximal fractures on X-ray and the presence of normal variants around the base of the metatarsal. Treatment of fifth metatarsal fractures is usually conservative unless the fracture is a proximal diaphyseal fracture. Proximal diaphyseal fractures (Jones and stress) require long periods of nonweightbearing immobilization or internal fixation as they are prone to delayed union. Delayed union may occur due to the mechanics of the fifth metatarsal and the poor blood supply to the proximal diaphysis. To avoid unsatisfactory long-term results, clinicians must be aware of the different types of fifth metatarsal fracture, in particular the proximal diaphyseal fractures.