Outcome predictors of limb salvage in traumatic popliteal artery injury.

Background: Significantly reduced amputation rates for traumatic popliteal artery injuries have been achieved with improved revascularization and resuscitative techniques. Predictive scores have failed to accurately predict outcomes in patients who sustain popliteal artery damage. This study aimed to identify predictors of limb salvage in a civilian cohort after popliteal artery trauma.

Methods: A single-institution, retrospective review was performed of all patients with popliteal artery trauma presenting between January 2002 and June 2009. Data were compiled using the institutional trauma registry, with demographics, mechanism of injury, associated injury, fasciotomy, Mangled Extremity Severity Score (MESS), and Injury Severity Score (ISS) all documented. Statistical analysis included descriptive statistics, univariate analysis, and multiple exact logistic regression.

Results: Seventy traumatic popliteal artery injuries were identified in 68 patients with a mean age of 33 years (range: 5-88 years). The majority of patients were male (n = 57; 81%), and 73% sustained blunt injury. Associated venous injury was present in 16 (23%) cases. Associated orthopedic injuries included 19 (27%) dislocations and 49 (70%) fractures. The median MESS was 5 (range: 2-9) and the median ISS was 9 (range: 4-41). Revascularization was performed in 62 cases (89%). Twenty-three percent of patients had compartment syndrome and 56% underwent fasciotomy. Fifteen (21%) patients required amputation, 11% of which were primary and 10% secondary. Variables associated with amputation included ISS >10 compared to ISS <9 (odds ratio [OR]: 7.4; P < 0.045), blunt injury (OR: 10.7; P = 0.009), MESS >7 (OR: 2.4; P < 0.0001), and fractures (OR: 0.13; P < 0.045). In a multiple exact logistic regression analysis, a MESS >7 (P < 0.05) was the only significant predictor of amputation.

Conclusion: Patients with traumatic popliteal artery injury are at high risk for amputation. Blunt injury, fractures, ISS >9, and MESS >7 were associated with an increased odds of amputation. Although in our data, MESS was the strongest predictor of amputation, we recognize that MESS was previously invalidated as a scoring system. New methods to determine limb viability in the mangled extremity are needed.