SCIENTIFIC ARTICLE Scapholunate Interosseous Ligament Injuries: A Retrospective Review of Treatment and Outcomes in 82 Wrists Eric M. Rohman, MD, Julie Agel, MA, Matthew D. Putnam, MD, Julie E. Adams, MD Purpose To compare outcomes of treatment for scapholunate instability between acute (< 6 wk from injury) and chronic (> 6 wk) injuries, between complete and partial tears, and among surgical techniques; identify risk factors for surgical failure; and compare ligament reconstruction with repair with or without capsulodesis in the chronic period. Methods We performed a retrospective chart review of 82 primary scapholunate interosseous ligament surgeries, with median follow-up of 150 days. A total of 27 patients underwent surgery in the acute period and 50 in the chronic period. (In 5 patients we were unable to determine acuity or chronicity of injury.) In the chronic period, 16 patients underwent repair with or without capsulodesis, 27 underwent ligament reconstruction, and 7 underwent other procedures. Results Surgical intervention in the acute setting involved more complex injuries, most commonly used direct repair, and produced a significantly lower failure rate than chronic intervention. In the chronic setting, the most common technique was ligament reconstruction, which produced superior radiographic outcomes compared with repair with or without cap- sulodesis. Isolated scapholunate interosseous ligament injuries undergoing chronic surgical intervention composed the majority of failures. Workers’ compensation status and chronic intervention were significant risk factors for failure. Conclusions For chronic injuries, ligament reconstruction produced better radiographic out- comes than repair with or without capsulodesis. Acute intervention (within 6 wk) was pref- erable to chronic intervention for scapholunate interosseous ligament injuries, and a substantial number of isolated injuries failed to receive treatment in the acute period. (J Hand Surg Am. 2014;39(10):2020e2026. Copyright Ó 2014 by the American Society for Surgery of the Hand. All rights reserved.) Type of study/level of evidence Therapeutic III. Key words Capsulodesis, scapholunate, SLAC, tenodesis, wrist. S CAPHOLUNATE (SL) INSTABILITY IS the most com- mon pattern of carpal instability. The theorized mechanism of injury is a fall on outstretched hand with extension, intercarpal supination, and ulnar devi- ation, 1,2 causing failure of the scapholunate interosseous ligament (SLIL). Secondary stabilizers may compensate for lost SLIL integrity, but these weaken with time. As this occurs, the scaphoid undergoes rotatory subluxation and the dorsal intercalated segment instability (DISI) From the Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, MN. Received for publication February 5, 2014; accepted in revised form June 27, 2014. No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. Corresponding author: Julie E. Adams, MD, Department of Orthopaedic Surgery, University of Minnesota, 2450 Riverside Avenue, Suite R200, Minneapolis, MN 55454; e-mail: adams.julie.e@gmail.com. 0363-5023/14/3910-0021$36.00/0 http://dx.doi.org/10.1016/j.jhsa.2014.06.139 2020 r Ó 2014 ASSH r Published by Elsevier, Inc. All rights reserved.