Workup of the Acute and Chronic Multiligament Injured Knee

A systematic approach for the assessment of multiligament knee injuries (MLKIs) is paramount in establishing a complete diagnosis and to avoid missing concomitant potentially limb-threatening injuries. Initial workup consists of a thorough history and physical examination to understand the mechanism of injury, associated injuries, and urgency of the remainder of the workup. In the acute setting, all life- and limb-threatening injuries should be the first priority. This typically includes a vascular exam with ankle-brachial index (ABI) and subsequent advanced vascular studies, as indicated. Standard radiographic views of the knee closely follow for evaluation for any associated fractures or dislocations that may require intervention. Once acute issues have been resolved or temporized, much of the workup for both acute and chronic injuries remains the same. Stress radiographs of the knee are recommended in conjunction with magnetic resonance imaging (MRI) to understand the magnitude of the injury to particular structures, which ultimately aids in surgical planning. Examination under anesthesia (EUA) provides additional haptic feedback information without the confounder of pain to help guide surgical decision-making. In the chronic setting, one must also take into account overall limb mechanical alignment, existing arthritis, and goals of the patient. Employing these workup techniques in a regimented fashion as detailed in this chapter will allow the practitioner to identify the full extent of the MLKI, guiding appropriate treatment moving forward.