Prognostic Value of Intraoperative Distal Radioulnar Joint Instability Grading in Distal Radius and Galeazzi Fractures: A Prospective Multicenter Cohort Study.

Despite anatomically successful fixation of distal radius and Galeazzi fractures, a subset of patients develops persistent pain and functional limitation, suggesting that factors beyond osseous alignment influence recovery. Distal radioulnar joint instability has been implicated in unfavorable outcomes, yet intraoperative assessment remains inconsistently standardized and has rarely been validated as a prognostic variable. This prospective multicenter observational cohort study included 120 consecutive patients with distal radius or Galeazzi fractures treated with plate fixation in two tertiary centers. After fracture reduction and stabilization, intraoperative distal radioulnar joint stability was systematically assessed using a previously published classification system comprising Grades I to III, with patients demonstrating no instability serving as the reference group. The primary outcome was the QuickDASH score at 12 months, while secondary outcomes included pain intensity, grip strength, radiographic distal radioulnar joint gap, and postoperative complications. Multivariable linear regression was used to evaluate the association between intraoperative instability grade and outcomes, adjusting for age, sex, fracture type, and treatment center. Increasing instability grade was independently associated with worse functional outcome, higher pain levels, reduced grip strength, and greater postoperative distal radioulnar joint widening at 12 months, with an adjusted increase of approximately 5 to 6 QuickDASH points per grade. Intraoperative distal radioulnar joint instability grading provides clinically relevant prognostic information and supports postoperative risk stratification following distal radius and Galeazzi fractures.