Advances and pitfalls of current multi-ligament knee injury classification systems: A narrative review

The purpose of this narrative review is to discuss current classification systems for multi-ligamentous knee injuries (MLKI), evaluate their utility in correlating with clinical outcomes, and identify weaknesses in existing systems. A targeted literature search was performed in PubMed/MEDLINE to identify articles relevant to MLKI, knee dislocation, classification systems, injury mechanism, neurovascular injury, periarticular pathology, and clinical outcomes. The most utilized systems are largely derived from knee dislocation systems, such as the Kennedy and Schenck systems, and focus primarily on ligamentous anatomy. More recent approaches incorporate additional variables, including periarticular pathology and mechanism, although utilization of these systems has remained low. Established anatomic systems remain useful for injury description and research, but current literature supports the need for an updated classification system. Future systems may benefit from integration of several additional variables, including injury mechanism, periarticular injury, neurovascular injury, and soft-tissue compromise. Further validation is required before existing or future systems can reliably guide prognosis or treatment.