Outcome of iatrogenic collateral ligaments injuries during total knee arthroplasty

Soft tissue balance is an essential step in total knee arthroplasty by providing a good knee stability and an even distribution of load over the prosthesis components. During surgery, because of the need of having a good balance in most cases is necessary to do some soft tissue release in the medial compartment. Lateral release is far more rare and is generally needed for patients with valgus knees after high tibial osteotomy. Our purpose is to evaluate the complications that arise during soft tissue release and how to manage this unfortunate events for getting the best functional results for the patients. In this study, we analyzed 434 knee arthroplasties that were operated in our clinic in the past 8 years by the same knee team (2005-2012). Average age was 64.8 years. Eight of this patients had medial collateral ligament injuries during surgery, and two had lateral collateral ligament rupture. Average age of patients who suffered from medial collateral ligaments injuries was 62.8 years and for lateral collateral ligaments was 72.5 years. Body mass index was 34 for both groups. We used for evaluation the knee society pain and functional scores, and X-rays obtained after the surgery with a calibrated Siemens machine. Seven patients with MCL repair were satisfied with after surgery (Knee Society score was 87.7, and functional score was 80). One complained of knee instability associated with pain and needed revision. In LCL group, all patients had excellent results (Knee Society score was 91.5, and functional score was 85). We found that repair to collateral ligaments injuries must be obtained during surgery, especially complete ruptures of the MCL. There are several approaches to collateral ligaments ruptures during total knee arthroplasty that will be discussed during the article.