Limb Salvage is Possible in Select Patients with Arterial Injuries and Elevated Mangled Extremity Severity Scores

Lower extremity trauma with vascular compromise is frequently associated with other injuries and requires emergent and complex decision-making. The Mangled Extremity Severity Score (MESS) is widely utilized to predict the need for amputation in these cases. As the tool was developed over 30 years ago, its accuracy in a modern trauma setting remains a topic of investigation and discussion. The purpose of this study was to investigate the correlation of an elevated MESS with the need for amputation in patients with traumatic lower extremity arterial injuries.

A retrospective chart review was performed on patients ≥18 years old with traumatic lower extremity arterial injuries at a level I trauma center from July 2012 to December 2023. Demographics, injury characteristics, interventions, and outcomes including amputation upon presentation, amputation during hospitalization, and amputation after discharge following limb salvage attempts were recorded.

In our cohort of 238 limbs with lower extremity arterial injury, median age was 33 years and majority of the patients were male (84.1%). The predominant mechanism was penetrating (65.1%). Eighty-four lower extremity injures had concomitant injuries (35.3%). The median MESS was 5 (IQR 3-6). Vascular repair was performed on 179 lower limbs (75.2%); 168 were open repairs (93.9%), nine endovascular (5.0%), and two hybrid (1.1%). Ninety-two limbs underwent concomitant orthopedic repair (38.7%). Six limbs underwent primary amputation (2.5%) after multidisciplinary consensus, all of which had a MESS ≥7. Of the 179 lower limbs that underwent vascular repair, 8.4% required amputation prior to discharge, and another 2.8% after discharge. Thirty-three lower extremities with a MESS ≥7 underwent vascular repair. The majority did not require a subsequent amputation (22/33, 66.7%). In the entire cohort, a MESS ≥ 7 was found to be significantly associated with any amputation (P<.0001) when compared to MESS <7. MESS ≥7 had significantly greater odds of amputation in both univariable (OR = 10.6; 95% CI: 4.65-24.1; p<0.0001) and multivariable analysis after adjusting for age, ischemia time, mechanism of injury, concomitant injuries, arterial injury location, and fracture status (aOR = 5.40; 95% CI: 1.79-16.3; p=0.003).

Lower extremity arterial injuries are frequently associated with complex orthopedic and soft tissue trauma. An increasing MESS, blunt mechanism, and the presence of multiple vascular injuries are significantly associated with the risk of limb loss. While a MESS of 7 or greater is predictive of an increased risk of amputation, limb salvage can still be achieved in many patients with prompt vascular repair despite high MESS.