Peripheral tears of the triangular fibrocartilage complex cause distal radioulnar joint instability after distal radial fractures.

The aim of this prospective study was to determine whether peripheral tears of the triangular fibrocartilage complex (TFCC) in patients younger than the osteoporotic age (males,<60 years; females, <50 years) were related to chronic distal radioulnar joint (DRUJ) instability. Fifty-one patients (27 women) with displaced distal radial fractures were included in the study. The median age was 41 years (range, 20-57 years). Arthroscopy at the time of fracture showed complete or partial TFCC tears in 43 patients (24 had only peripheral tears, 10 had only central perforations, and 9 had combined tears). The 1-year (range, 11-27 months) follow-up period included an interview, physical examination, and radiographic evaluation. Ten of the 11 patients with complete peripheral TFCC tears had DRUJ instability at the follow-up examination compared with 7 of the 32 patients with only partial or no peripheral tears. Patients with instability of the DRUJ had a worse Gartland and Werley wrist score. Instability was not associated with any radiographic finding either at the time of fracture or at the follow-up examination. Initial fracture or nonunion of the styloid was even slightly more common in stable patients.