The outcome of 57 patients with isolated lunotriquetral injuries treated by arthrodesis, direct ligament repair, or ligament reconstruction was evaluated. Eight underwent reconstruction using a distally-based strip of the extensor carpi ulnaris, 27 had direct repair, and 22 had arthrodesis. Patient findings included local tenderness and positive provocative maneuvers. However, lunotriquetral ballottement, shear, and compression were positive in only 65%, 53%, and 65%, respectively. “Minor” VISI instability was noted in 6 patients, although “minor” is not defined.
Follow-up was long; 10.5 years after arthrodesis, 16.6 years after reconstruction, and 6.7 years after repair. Objective measures of outcome (strength and motion) were significantly better in the reconstruction and repair group, although DASH scores were similar in each group. Workers’ compensation was associated with a poorer outcome. Arthrodesis was associated with a 41% nonunion rate and persistent complaints, often related to ulnar impaction.
This study lends additional insight into the treatment of isolated lunotriquetral injuries. This relatively benign injury can be associated with persistent symptoms, most likely attributed to a disruption of carpal kinematics. Isolated arthrodesis seems logical, although ulnar impaction and nonunion are common sequelae. Reconstruction with a strip of tendon may produce enough scar to limit abnormal motion between the lunate and triquetrum. However, in this study, the reconstruction group is an extremely small cohort and additional numbers are necessary to support this operation as the procedure of choice for chronic isolated lunotriquetral instability. Lastly, this procedure is NOT indicated in cases of established VISI deformity, which indicates a greater degree of ligamentous disruption than just the lunotriquetral complex. Ulnar shortening must be a considered mode of treatment as well, especially in ulnar positive individuals.