Is there any benefit in the combined ligament reconstruction with osteotomy compared to ligament reconstruction or osteotomy alone?: Comparative outcome analysis according to the degree of medial compartment osteoarthritis with anterior or posterior cruciate ligament insufficiency

Introduction The purpose of this study was to compare the outcomes of middle-aged patients with anterior cruciate ligament (ACL) or posterior cruciate ligament (PCL) insufficiency by assessing different groups: high tibial osteotomy (HTO), HTO with combined ligament reconstruction, and isolated ligament reconstruction according to the alignment change and medial compartment osteoarthritis (OA). Materials and methods From 2014 to 2019, middle-aged (40–65 years) patients with knee instability were enrolled in this retrospective study. They were categorized into three groups: group I, HTO; group II, HTO with combined ACL or PCL reconstruction; and group III, isolated ligament reconstruction. Radiological outcomes, including Kellgren-Lawrence grade, mechanical femorotibial angle (mFTA), weight-bearing line (WBL) ratio, and posterior tibial slope were compared. Knee stability and clinical outcomes were also compared. Results Seventy-nine patients completed the final assessment. Group I was older than other two groups ( p = 0.006). Groups I and II had a higher body mass index ( p = 0.043) and more preoperative varus alignment than group III ( p < 0.001). OA severity was ranked in the order of group I, II, and III ( p < 0.001). Group I showed more valgus alignment than group II after HTO ( p = 0.024 for mFTA and 0.044 for WBL ratio, respectively). Compared to their preoperative status, all three groups showed significant improvement in knee stability ( p < 0.001); however, group I showed inferior knee stability regardless of ACL or PCL reconstruction ( p < 0.001 and 0.043, respectively). All clinical scores significantly improved in the three groups ( p < 0.001), and they showed comparable clinical outcomes in the final assessment. Conclusions Our strategy in managing middle-aged patients with knee instability according to the varus alignment and medial degeneration showed favorable stability and clinical outcomes. Middle-aged patients with knee instability should be managed with different strategies depending on their status. Level of evidence Case–control study; Level-III.