Concomitant periarticular fractures predict worse patient-reported outcomes in multiligament knee injuries: a matched cohort study

There is a shortage of high-level evidence regarding periarticular fractures affect outcomes after MLKIs. The purpose of this study was to determine whether concomitant periarticular fractures with mutliligament knee injuries (MLKIs) predict worse patient-reported outcomes (PROMs) when compared to MLKIs without concomitant periarticular fractures after surgical repair and/or reconstruction. Medical records of patients who sustained MLKIs from January 1, 2009 to June 1, 2014 were retrospectively reviewed. All patients aged 18–65 years with grade III injuries of two or more knee ligaments and 1-year minimum follow-up were included. Patients with injuries or surgeries to either knee before their MLKIs were excluded. Radiographs and computed tomography imaging obtained at the time of injury were used to detect concomitant periarticular fractures. Patients with and without concomitant periarticular fractures were matched on a 1:2 basis, respectively. Multiple PROMs were collected, including the IKDC Subjective Knee Form (IKDC-SKF), and Knee Injury and Osteoarthritis Outcome Score (KOOS). The independent t-test was used to compare PROMs between patients with and without periarticular fractures. Eighteen patients (10 males, 8 females) with a mean follow-up of 4.0 years (range 1.1–8.6 years) were included in the final analysis, with six patients having MLKIs and concomitant periarticular fractures. Compared to patients with isolated ligamentous MLKIs (n = 12), patients with concomitant periarticular fracture (n = 6) demonstrated significantly worse outcomes on the IKDC-SKF (54.2 ± 13.3 vs. 74.0 ± 19.6, p = 0.04) and KOOS-Sports and Recreation subscale (41.2 ± 32.4 vs. 70.8 ± 19.4, p = 0.03). The presence of a periarticular fracture predicted significantly worse clinical outcomes in the setting of MLKI. These findings may be useful in determining the prognosis of MLKI with concomitant periarticular fractures treated with surgical repair and/or reconstruction.