A lateral wrist radiograph shows a small bone fragment (arrow) dorsum to the wrist with overlying soft tissue swelling.
- 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
- 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.
Simon RR, Koenigsknecht SJ. Emergency orthopedics: the extremities, 2001.