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A 13-year-old boy inverted his ankle while playing basketball in his driveway. He felt a pop and had immediate pain. He had tenderness over the base of his fifth metatarsal. Having met the Ottawa ankle rules for radiographs (see Management Section), a radiograph was obtained, which revealed a displaced styloid fracture at the base of the fifth metatarsal (Figure 85-1).
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Most metatarsal fractures in children over the age of 5 years involve the fifth metatarsal and include avulsion fractures at the base, acute diaphyseal fractures (Jones fracture), and diaphyseal stress fractures (Figure 85-2). Fractures of the first through fourth metatarsals are less common but can be associated with a Lisfranc injury. Children under the age of 5 years more commonly fracture the first metatarsal. Diagnosis is based on the mechanism of injury or type of overuse activity and radiographic appearance. Treatment depends on the type of fracture. Most metatarsal fractures have a good prognosis; however, Jones fractures have a high rate of nonunion and Lisfranc injuries can result in chronic symptoms.
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Avulsion fracture at base of fifth metatarsal: fifth metatarsal tuberosity fracture, dancer fracture, pseudo-Jones fracture.
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Jones fracture—Acute diaphyseal fracture of the fifth metatarsal.
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Foot fractures are common injuries among recreational and serious athletes; however, incidence and prevalence in most populations is unknown.
Children under the age of 5 years most frequently fracture the first metatarsal, generally from a fall from a height.1
Children over the age of 5 years most frequently fracture the fifth metatarsal generally from a fall on a level surface.1
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Etiology and Pathophysiology
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Avulsion fractures result when the peroneus brevis tendon and the lateral plantar fascia pull off the base of the fifth metatarsal, typically during an inversion injury while the foot is in plantar flexion.
Jones (acute diaphyseal) fracture results from landing on the outside of the foot with the foot plantar flexed.
Stress fractures at base of second and third metatarsal bones are seen in repetitive trauma in ballet dancing.
Diaphyseal stress fractures are caused by chronic stress from ...