The two most common types of fractures in this location are: (1) the avulsion fracture of the proximal articular margin of the fifth metatarsal bone and (2) the Jones fracture.

The articular fracture, also known as a dancer’s fracture, accounts for greater than 90% of fifth metatarsal base fractures and occurs from tension at the peroneus brevis insertion, resulting in a fracture line that is less than 1.5 cm from the tip of the tuberosity. In the majority of cases, the fracture line is extra-articular and proximal to the level of the metatarsocuboid joint. It is important not to confuse this fracture with a normal apophysis, which is usually present between the ages of 9-14 years, runs parallel to the shaft of the metatarsal along the inferolateral margin of the tubercle, and does not extend proximally into the joint. In contradistinction to the Jones fracture (see below), an articular fracture generally heals easily with placement of a short leg weight-bearing cast for 4-6 weeks and seldom requires internal fixation.

By definition, a Jones fracture occurs at the proximal diaphyseal-metaphyseal junction or in the proximal diaphyseal region of the fifth metatarsal bone, at a distance of 1.5-2 cm (approximately 1 inch) distal to the tuberosity. Jone’s fractures may be acute or chronic: the acute form results from an impaction twisting/inversion foot injury, whereas the chronic form usually develops as a stress fracture. In comparison to the articular avulsion fracture described above, the Jones fracture, particularly the chronic type, has a higher incidence of delayed union, nonunion, fibrous union, and/or refracture. Acute fractures may sometimes be managed with a non weight-bearing cast for 6-8 weeks. Chronic fractures and cases of nonunion require fluoroscopically-guided K-wire insertion (to determine proper position and length), followed by incision and placement of a cancellous bone screw (usually a 4.5 mm cannulated screw) +/-bone graft (from the tuberosity and/or drill bone bits). Radiographic evidence of delayed union or malunion includes persistent fracture lines through both cortices, periosteal callus formation (visible with a hot lamp), and intramedullary sclerosis.

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Sir Robert Jones, an English orthopaedic surgeon (1858–1933)