5th Metatarsal Base Avulsion Fracture vs. Jones Fracture

History: Ankle inversion injury with lateral foot pain

Do you see the difference? One's a ticket to a walking boot and 4-6 weeks of jokes about clumsiness. The other's a one-way train to the bone stimulator station with a layover in non-union town.

Both are 5th metatarsal base fractures, but location is everything. Let's dissect the differences:

Avulsion Fracture

• Fracture line is proximal to the 4th-5th metatarsal articulation
• Typically transverse orientation (perpendicular to the long axis)
• Often involves just the tuberosity tip
• Caused by sudden pull from the lateral cord of the plantar aponeurosis or peroneus brevis tendon during inversion

Jones Fracture

• Fracture line is distal to the 4th-5th metatarsal articulation, within 1.5-3 cm of the base
• Typically oblique or transverse orientation
• Occurs in the metaphyseal-diaphyseal junction (watershed zone)
• Often seen in athletes with fatigue/stress mechanisms

Why does this distinction matter? Two words: blood supply.

The proximal tuberosity (avulsion territory) enjoys robust retrograde blood flow, while the metaphyseal-diaphyseal junction (Jones territory) is a watershed zone with poor circulation. This vascular discrepancy means avulsion fractures typically heal within 4-6 weeks with conservative treatment, while Jones fractures are notorious for delayed union, non-union, and refracture.

Our orthopedic colleagues will appreciate your distinction because management differs dramatically:

• Avulsion: Usually treated conservatively with walking boot or cast
• Jones: Often requires surgical fixation (especially in athletes), bone stimulation, and longer immobilization

Search pattern tip: When you see a lateral foot film ordered for "ankle pain," always check the 5th metatarsal base! It's a common miss when everyone's focused on the ankle mortise.

And remember – location, location, location. The difference between a 6-week annoyance and a 6-month nightmare can be just a few millimeters.