Ankle-Brachial Index Is an Effective Screening Tool for Vascular Injury in Schatzker Type-4 to 6 Tibial Plateau Fractures with Symmetric Pulses.

Abstract

Schatzker type-4 to 6 tibial plateau fractures most commonly occur when the distal femur is driven through the proximal tibial articular surface. This mechanism of injury can be equivalent to a knee dislocation and carries an increased risk of vascular injury. Our institution screens all Schatzker type-4 to 6 tibial plateau fractures with symmetric pulses for a vascular injury by measuring the ankle-brachial index (ABI). The purpose of this study was to describe our screening protocol and to determine its effectiveness at identifying vascular injuries. Our screening protocol consisted of measuring the ABI of the injured limb for all Schatzker type-4 to 6 tibial plateau fractures that presented with symmetric pulses. An ABI of ≤0.9 prompted a computed tomographic angiogram (CTA) of the injured extremity. We retrospectively reviewed all Schatzker type-4 to 6 tibial plateau fractures from 2006 to 2023 that presented to a single level-I academic trauma center. We collected demographic, fracture, ABI, and vascular injury data and examined the effectiveness of our screening protocol. We identified 437 Schatzker type-4 to 6 tibial plateau fractures (mean age, 47 years; 59% male). There were 102 (23%) Schatzker type-4 fractures, 4 (1%) type-5 fractures, and 331 (76%) type-6 fractures. Eight fractures (2%) had a concomitant vascular injury; none of the vascular injuries were missed. An ABI of ≤0.9 had a positive predictive value of 0.250, and an ABI of >0.9 had a negative predictive value of 1.000. The sensitivity of the ABI was 1.000, whereas the specificity was 0.056. Thirty-seven fractures were in patients with an ABI of >0.9 at presentation who underwent a CTA of the injured limb for nonorthopaedic indications, with no vascular injuries identified. The ABI has frequently been cited as a valuable screening tool for vascular injury after a knee dislocation, but its application to Schatzker type-4 to 6 tibial plateau fractures had not yet been described. Our results indicate that this screening protocol is both safe and effective, with no missed vascular injuries over a 17-year period. Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.