Do triangular fibrocartilage complex foveal injuries affect the clinical outcome of ulnar shortening osteotomy for ulnar impaction syndrome?

BACKGROUND

Ulnar shortening osteotomy (USO), as its name implies, is used to shorten the ulna. It subsequently tightens the triangular fibrocartilage complex (TFCC) and ulnar wrist. TFCC foveal insertion is a primary stabilizer of the distal radioulnar joint. It is unclear whether USO is effective in TFCC foveal injuries. The purpose of this study was to review the clinical outcomes of ulnar shortening osteotomies with and without TFCC foveal injuries.

METHODS

We retrospectively reviewed patients with ulnar wrist pain treated with USO and wrist arthroscopy including the distal radioulnar joint (DRUJ). Sixty-five patients were included in this study. An algorithm was used to guide surgical decision-making. After arthroscopic confirmation of ulnar impaction syndrome, we performed USO with a locking compression plate (mean length of shortening, 2.7 mm; range, 1-7.5 mm). The flattened TFCC disc due to ulnar shortening was confirmed arthroscopically. If the DRUJ was unstable after USO, we repaired the TFCC foveal insertion.

RESULTS

There were 32 post-traumatic and 33 idiopathic cases. We detected TFCC disc injuries in 34 wrists and TFCC foveal injuries in 33 wrists; both types were found in 15 wrists. TFCC foveal injuries were not significantly correlated with patient age, history of trauma, or clinical outcome. Most patients showed good clinical outcomes; 31 of 65 patients had preoperative DRUJ instability, with a significant number having foveal but not disc injuries.

CONCLUSION

USO achieved reasonable outcomes, even in patients with TFCC foveal injuries. In cases demonstrating ulnar impaction, USO should be prioritized over TFCC repair.