External fixation increases complications following surgical treatment of multiple ligament knee injuries.

Purpose: The purpose of this study was to review post-operative complications after surgical intervention of MLKIs within the first 6 months to be better able to counsel patients before surgical intervention.

Methods: All patients who underwent surgical reconstruction for a MLKI at one institution from 2009 to 2018 were included in this study. A retrospective review was performed of all patients and post-operative complications were recorded, including motion loss (which included > 10 degree flexion loss or > 3 degree extension loss), hematoma formation, infection, iatrogenic vascular or nerve injury, deep vein thrombosis (DVT), pulmonary embolism (PE), skin lesions, symptomatic hardware, recurrent ligamentous laxity, and need for additional surgery. Knee ligament injuries were classified based on the Schenck Knee Dislocation (KD) Classification.

Results: A total of 136 patients were included in this study, 83 with KD I injuries, 40 with KD III injuries, 9 with KD IV injuries, and 4 with KD V injuries. Of these total patients, 48 (35.5%) sustained a post-operative complication: 11 out of 133 (8.3%) from 0 to 1 week, 46 out of 132 (34.8%) from 1 week to 1 month, 28 out of 124 (22.6%) from 1 to 3 months, and 26 out of 121 (21.5%) from 3 to 6 months. Out of the total complications, 99 (78.5%) occurred at 1 week-3 months post-operation. Patients who had an external fixator placed at initial injury were more likely to sustain a post-operative complication. The most common complication was motion loss in 39 (28.6%) patients. There was a significant difference in mean number of complications between the KD I and KD III groups, as well as the KD III and KD IV-V groups. There was no significant difference in the overall prevalence of post-operative complications or occurrence of motion loss with KD grade.

Conclusion: The main finding of this study was 48 (35.5%) patients sustained a complication after surgical treatment of MLKIs, with 99 (78.5% of all complications) complications occurring at 1 week-3 months post-operation. Patients who had an external fixator placed at initial injury were more likely to sustain a post-operative complication. The most common post-operative complication was motion loss in 39 (28.6%) patients. The KD grade was not associated with post-operative development of motion loss, but KD III had a significantly greater mean number of complications than KD I or KD IV-V grades.

Level Of Evidence: IV.