No false elevation in ankle brachial index in patients with tibial plateau fractures and vascular risk factors

Abstract

ObjectivesThe ankle brachial index (ABI) is a useful tool in detection of lower extremity vascular injury. However, diabetes mellitus (DM), chronic kidney disease (CKD), and peripheral vascular disease (PVD) may affect extremity perfusion leading to possible false elevation of the ABI value. If true in trauma patients, this can affect initial evaluation, diagnostics, and management. We therefore explored mean ABI values in tibial plateau fractures of patients with vascular risk factors to help determine whether there is a difference. DesignThis is a retrospective chart review of patients sustaining tibial plateau fractures with a specific ABI value recorded in the medical record. Patients were identified as either having vascular risk factors or not and data analysis performed to determine if their ABI differed and whether they were more likely to have a vascular injury. Results282 acute tibial plateau injuries with specific ABI values were identified, 46 of which carried the risk factors in question. The average risk factor group ABI was 0.95 ± 0.15 versus those without risk factors 1.0 ± 0.15 (p = 0.057). No patient with risk factors required a vascular intervention or four-compartment fasciotomy. ConclusionsThis study shows no statistical significance between the presenting ABI of patients with risk factors such as DM, CKD, or PVD and those without those risk factors who sustained acute tibial plateau fractures. Therefore, in general the ABI still holds as a useful screening tool for evaluation of vascular insult in the setting of acute lower extremity trauma.