Radioulnar Ligament Avulsion in Distal Radius Fractures Associated with Ulnar Styloid Fractures

摘要

The radioulnar ligament was prospectively examined from intraoperative findings in distal radius fractures associated with ulnar styloid fractures. Sixty-six cases were subjected to surgery. We evaluated TFCC injuries by arthroscopy, and evaluated a radioulnar ligament avulsion directly when we repaired fractured ulnar styloid process. In the 15 cases (23%), a radioulnar ligament was avulsed at a fovea of the ulna. Avulsion of a radioulnar ligament was found in the nine cases (38%) out of the 24 distal radius fractures under AO classification C2 or C3, and found in the 10 cases (33%) out of the 30 ulnar styloid fractures under Nakamura's classification base or proximal. When a radioulnar ligament is lacerated at a fovea of the ulna, it occurs with instability of DRUJ. The risk of DRUJ instability was found to be increased in the cases with distal radius fracture under AO classification C2 or C3, or the cases with ulnar styloid fracture under Nakamura's classification base or proximal.