Differentiation in an inclusive trauma system: allocation of lower extremity fractures.

Background: Implementation of an inclusive trauma system leads to reduced mortality rates, specifically in polytrauma patients. Field triage is essential in this mortality reduction. Triage systems are developed to identify patients with life-threatening injuries, and trauma mechanisms are important for triaging. Although complex extremity fractures are mostly non-lethal, these injuries are frequently the result of a high-energy trauma mechanism. The aim of this study is to compare injury and patient characteristics, as well as resource demands, of lower extremity fractures between a level (L)1 and level (L)2 trauma centre in a mature inclusive trauma system. Methods: This is a retrospective cohort study. Patients with below-the-knee joint fractures diagnosed in a L1 or L2 trauma centre between July 2013 and June 2015 were included. Main outcome parameters were patient demographics, trauma mechanism, fracture pattern, and resource demands. Results: One thousand two hundred sixty-seven patients with 1517 lower extremity fractures were included. Most patients were treated in the L2 centre (L1 = 417; L2 = 859). Complex fractures were more frequently triaged to the L1 centre. Patients in the L1 centre had more concomitant injuries to other body regions and ipsi- or contralateral lower extremity. Patients in the L1 centre were more resource demanding: more surgeries (> 1 surgery; 24.9% L1 vs 1.4% L2), higher immediate admission rates (70.1% L1 vs 37.6% L2), and longer length of stay (mean 13.4 days L1 vs 3.1 days L2). Conclusion: The majority of patients were treated in the L2 trauma centre, whereas complex lower extremity injuries were mostly treated in the L1 centre, which placed higher demand on resources and labour per patient. This change in allocation is the next step in centralization of low-volume high complex care and high-volume low complex care.