Triquetral Fracture

A lateral wrist radiograph shows a small bone fragment (arrow) dorsum to the wrist with overlying soft tissue swelling.

Facts:

• Second most common carpal bone fracture
• Two main types: dorsal chip fracture and body fracture
• Dorsal chip fracture (like in our case ) believed to be due to forceful impingement of the triquetrum during wrist hyperextension
• Body fracture frequently associated with perilunate dislocation (direct blow)
• Pain and swelling localized at the dorsum of the wrist where triquetrum is located
• Complication: motor branch of ulnar nerve injury

Imaging

• Chip fracture best seen on lateral radiograph with hand in flexion
• Body fracture best seen on AP and oblique radiographs
• Fractures are possibly underreported. CT can help in suspected cases.

Reference:

Simon RR, Koenigsknecht SJ. Emergency orthopedics: the extremities, 2001.