Background: The 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 effect extremity perfusion leading to possible false elevation of 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.
Hypothesis: We hypothesize that the ankle brachial index measurements used in evaluation of tibial plateau fractures concerning for vascular injury will be falsely elevated in patients with vascular risk factors in comparison to those without risk factors.
Methods: This is a retrospective chart review of patients sustaining tibial plateau fractures with a specific ABI value recorded in the medical record at a Level 1 academic trauma center, Wake Forest Baptist Medical Center. Patients were identified as having either vascular risk factors or not and data analysis was performed to determine if their ABI differed and whether they were more likely to have vascular injury.
Results: 282 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 +/1 0.15 (p=0.057). No patient with risk factors required a vascular intervention or four-compartment fasciotomy.
Conclusions: This study shows no statistical significant between the presenting ABI of patients with risk factors such as DM, CKD or PVD and those without those risk factors who sustained 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.
Source of mentor’s funding or other support that funded this research: none