Background: Ulnar shortening osteotomy (USO) is an effective treatment for ulnar impaction syndrome. However, there has been a concern of osteoarthritis (OA) developing at the distal radioulnar joint (DRUJ) if USO is performed on patients with a reverse oblique sigmoid notch. This study aimed to evaluate the radiographic and functional outcomes following USO in patients with a reverse oblique sigmoid notch.Methods: We retrospectively reviewed our patients with a reverse oblique sigmoid notch who underwent USO to treat ulnar impaction syndrome between 2002 and 2013. We evaluated the radiographic changes of the DRUJ and the patients’ functional outcomes.Results: We enrolled 22 patients (22 wrists) with an average age at operation of 49.6 years and mean follow-up of 93.2 (range, 36 - 179; SD 38.2) months. We found that there were changes in the inclination angle of the sigmoid notch, from an average of reverse oblique 14.9o (range, 11o - 23o; SD 3.4o) preoperatively to a more parallel 5.1o (range, 0o - 11o; SD 3.2o) at the final follow-ups. The functional results at the final follow-ups were good with a mean VAS for pain of 0.2 (range, 0 - 1; SD 0.4) at rest and 1.3 (range, 0 - 3; SD 0.9) during activity, QuickDASH of 15.1 (range, 2.3 - 34.1; SD 8.8), and modified Mayo Wrist Score of 91.6 (range, 70-100; SD 6.4). Seven wrists (31.8%) were noted to have OA changes, but the wrists did not exhibit a significantly worse function when compared to wrists without OA changes, except for supination motion and grip strength.Conclusions: For those patients with a reverse oblique sigmoid inclination following USO, we observed that the inclination angle would have a tendency to become more parallel and some patients would develop OA changes at the DRUJ, but the functional outcomes could still be good in the long term. The reverse oblique sigmoid inclination seems not to be an absolute contraindication for USO.

Background The surgical technique of radius distraction for stabilization of distal radioulnar joint (DRUJ) if intraoperative DRUJ instability was found after the fixation of distal radius fracture has been previously described, but this surgical technique lacks clinical and radiographic effect in minimal 3 years follow-up. We therefore evaluated the clinical outcome and radiographic results of radius distraction in minimal 3 years follow-up as long-term evaluation. Methods We reviewed the case series of distal radius fracture with concomitant DRUJ instability receiving radius distraction from the senior author over a 5-year period (January 1st, 2013, to June 30th, 2017) retrospectively. Radius distraction during volar plating was performed by moving the volar plate distally via compression screw loosening/fastening to achieve firm endpoint on the dorsopalmar stress test. The evaluations of radiographic, including bone union time and ulnar variance, and clinical outcomes, including grading of DRUJ instability, NRS of wrist pain, DASH score, MMWS score, and range of motion of operated wrist at final follow-up, were performed at clinic as minimum 3-year follow-up; a total 34 patients had been evaluated. Results At minimal post-operative 36 months follow-up, all cases demonstrated acceptable wrist range of motion with stable DRUJs, low NRS of wrist pain (0.6, SD 0.7), and satisfactory DASH score (mean 9.1, SD 6.2) and MMWS score (mean 87, SD 10). There were no cases suffering from nonunion of distal radius. The mean ulnar variance of injured wrist and uninjured wrist were -1.2 mm and 0.2 mm, respectively (SD 1.0 and 0.6) with significant statistical difference. Conclusions Radius distraction during volar fixation of distal radius fracture should be considered if DRUJ instability was found by the dorsopalmar stress test intraoperatively, and the long-term DRUJ stability could be achieved by maintenance of normal-to-negative ulnar variance, with decreased wrist pain and satisfactory function outcome. Level of Evidence Therapeutic Level IV

Background Dynamic radiocarpal instability is one of the causes of post-trauma radial-sided wrist pain. It is not easy to diagnose and may possibly be overlooked. The key ligaments responsible for dynamic radiocarpal instability are the radioscaphocapitate (RSC) and long radiolunate (LRL) ligaments. Tensioning of these 2 ligaments could be a method of treatment for dynamic carpal instability. We proposed a method for arthroscopic thermal shrinkage of these 2 ligaments, and for setting a landmark arthroscopically to facilitate identification of these 2 ligaments during the combined open suture tensioning procedure. Methods Between January 2016 and May 2020, 12 patients treated with this method were enrolled. The mean age was 33.3 years (range, 18–57 years), and the mean duration from injury to operation was 7.8 months (range, 3–25 months). The diagnosis was mainly depended on the physical examinations and confirmed under arthroscopy. The mean follow-up was 17.7 months (range, 12–26 months). Results All the patients had marked improvement of pain, grip strength, the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH), and the radiocarpal stability. The wrist range of motion showed significant decrease around 5o in both flexion and extension and around 4o in the ulnar deviation at the final follow-ups. All patients were able to return to their previous full level of work and activities. Conclusions We conclude that arthroscopic thermal shrinkage combined with open suture tensioning can be effective in treating dynamic carpal instability, while the arthroscopic-assisted landmark setting can help identify the accurate location of the RSC and LRL ligaments without dissecting too much soft tissue.