What is the diagnosis?

Base of the 5th metatarsal fracture with a normal proximal 5th metatarsal apophysis.

• Pearl: Proximal 5th metatarsal apophysis usually evident on X-ray around age 10 for females and 12 for males. They usually fuse 2-4 years later [2].

Image 2. Labeled oblique X-ray outlining fracture line and apophysis line. Case courtesy of Alexandra Stanislavsky, Radiopaedia.org, rID: 53737

What is the mechanism of injury?

The base of the fifth metatarsal bone is usually fractured when the foot is forcefully turned inwards while putting weight through the leg [3].

What physical exam findings are expected?

Tenderness to palpation along bone at fracture site and difficulty/inability to bear weight on affected foot.

Which imaging modalities can be used?

X-rays are typically sufficient for diagnosis. Recommended views: AP, lateral and oblique foot.

MRI indicated if X-rays are equivocal but high suspicion for stress fracture

CT indicated to evaluate fracture healing in the setting of delayed/nonunion or s/p surgical fixation.

What is the initial management?

When do you consult Orthopedics?

Orthopedics should be consulted if the fracture is significantly displaced (>2mm displacement or ten degrees of plantar angulation of neck or shaft fractures), there is a diaphyseal fracture (Zone 2/3), or shows signs of delayed healing or refracture. Also consider if the patient is a highly competitive athlete and surgical fixation may allow return to sport faster.