MULTI-LIGAMENT KNEE INJURIES: ASSESSMENT OF MECHANISM, INJURY PATTERN, ASSOCIATED INJURIES AND OUTCOME.

Abstract

Introduction and Aims: Knee dislocation is an uncommon but serious injury. This study assessed the initial mechanism of injury, pattern of ligament injury, osteochondral and peri-articular soft-tissue trauma, and associated neurovascular injuries in the multi-ligament knee injury. Outcomes following operative and non-operative management were reviewed.

Method: Retrospective review of patients with multi-ligament knee injuries was performed. Inclusion criteria were either a confirmed knee dislocation, or complete rupture of two or more ligaments requiring reconstruction. Systematic review of hospital records and imaging was performed for all patients, and clinical assessment, including validated outcome scores, were performed in the majority of patients. All reconstructive surgery was performed by the two senior authors.

Results: Forty-five patients with 47 knee injuries were identified over a 13-year period (1990–2003). The most common mechanisms of injury were motorcycle and motor vehicle accidents. Other mechanisms included pedestrians hit by cars, sporting injuries and falls. Approximately half had a documented knee dislocation, while the remainder were located at the time of presentation. Vascular injury occurred in around 25% of patients, all having positive clinical findings. Routine angiography was not performed in the absence of positive clinical findings. Neurological injury also occurred in approximately 20% of patients. Transient neuropraxia was more common than permanent nerve palsy, and there was an association between neurological and vascular injury. Associated injuries were varied, the most frequent being long-bone fracture. A significant number of patients had no associated injuries. Injury patterns were varied, though correlations were found between the reported mechanism and the pattern of ligament rupture and osteochondral injury. The majority of cases were managed with operative repair, and assessment of outcomes revealed that most returned to a good level of function, with some minor objective residual laxity and/or stiffness.

Conclusion: Multi-ligament injuries of the knee are uncommon but serious injuries with potentially catastrophic consequences. This detailed analysis provides correlation between mechanism and resulting injury to the knee and periarticular structures. The analysis of this large series provides valuable information to better understand natural history, and improve future management.