Presentation
Patient lost balance while doing a handstand. Tenderness and swelling to dorsum of left hand.
Patient Data
Third and fourth metacarpal head fractures are noted, likely secondary to an acute bony impaction injury. The joint spaces are preserved and within normal limits. The visualized soft tissues show normal appearance. No malalignment is identified. No soft tissue abnormality is seen.
Small avulsion fracture fragment at the radial margin of the third and fourth metacarpal heads again noted. The joint spaces remain within normal limits. No malalignment or soft tissue abnormality is seen.
Case Discussion
Metacarpal fractures are the most common hand injury accounting for approximately 40% of all hand injuries. Fractures of the metacarpal heads, however, are quite rare and typically result from a direct blow, crush injury, or, in this case, a fall.
One explanation for the mechanism of injury in this patient is through a rupture of the radial collateral ligaments of the third and fourth metacarpals from torsional stress leading to an avulsion fracture.