This study investigates the question of whether open repair of acute distal radioulnar joint instability at the time of volar plating of distal radius fractures would enable early mobilization of the wrist without the risk of distal radioulnar joint instability. We evaluated 29 patients of mean age 53 years with a distal radius fracture and acute distal radioulnar joint instability who underwent volar plating of the radius combined with surgical repair of the triangular fibrocartilage complex or an ulnar styloid base fracture, followed by active motion exercise of the wrist at 1 week after surgery. At 1 year after treatment, all patients had a stable distal radioulnar joint and grip strength averaged 90% of the normal side. This study demonstrates that surgical repair of the triangular fibrocartilage complex or ulnar styloid fracture followed by early mobilization did not result in distal radioulnar joint instability, and suggests that the surgical treatment of distal radioulnar joint instability may permit early mobilization of the wrist in patients who are considered suitable for rapid rehabilitation after surgery. Type of study: Therapeutic Level IV.