Shaft fractures of the first metatarsal are usually oblique or spiral. If the fracture is transverse suspect that it may be pathological. Check also for Lisfranc injuries as injury to the first metatarsal may be part of a Lisfranc complex.
Conventional radiographs of the foot. AP and lateral oblique are sufficient for diagnosis and treatment.
If pain and swelling of adjacent TMTs is present, a CT scan or MRI should be ordered to assess for a Lisfranc injury.
The clinical picture includes swelling, ecchymosis, and pain over the first metatarsal. Tenderness of adjacent TMTs should also be assessed, if Lisfranc is suspected.
Pearl Midfoot plantar ecchymosis is often associated with Lisfranc injury.