TY - JOUR A1 - Horst, Klemens A1 - Greven, Johannes A1 - Lüken, Hannah A1 - Zhi, Qiao A1 - Pfeifer, Roman A1 - Simon, Tim-Philipp A1 - Relja, Borna A1 - Marzi, Ingo A1 - Pape, Hans-Christoph A1 - Hildebrand, Frank T1 - Trauma severity and its impact on local inflammation in extremity injury—insights from a combined trauma model in pigs T2 - Frontiers in immunology N2 - Background: Extremity fracture is frequently seen in multiple traumatized patients. Local post-traumatic inflammatory reactions as well as local and systemic interactions have been described in previous studies. However, trauma severity and its impact on the local immunologic reaction remains unclear. Therefore, fracture-associated local inflammation was investigated in a porcine model of isolated and combined trauma to gain information about the early inflammatory stages. Material and Methods: Polytrauma (PT) consisted of lung contusion, liver laceration, femur fracture, and controlled hemorrhage. Monotrauma (MT) consisted of femur fracture only. The fracture was operatively stabilized and animals were monitored under ICU-standard for 72 h. Blood, fracture hematoma (FH) as well as muscle samples were collected throughout the experimental period. Levels of local and systemic pro- and anti-inflammatory as well as angiogenetic cytokines were measured by ELISA. Results: Both groups showed a significant decrease in pro-inflammatory IL-6 in FH over time. However, concentrations in MT were significantly higher than in PT. The IL-8 concentrations initially decreased in FH, but recovered by the end of the observation period. These dynamics were only statistically significant in MT. Furthermore, concentrations measured in muscle tissue showed inverse kinetics compared to those in FH. The IL-10 did not present statistical resilient dynamics over time, although a slight increase in FH was seen by the end of the observation time in the MT group. Conclusions: Time-dependent dynamics of the local inflammatory response were observed. Trauma severity showed a significant impact, with lower values in pro- as well as angiogenetic mediators. Fracture repair could be altered by these trauma-related changes of the local immunologic milieu, which might serve as a possible explanation for the higher rates of delayed or non-union bone repair in polytraumatised patients. KW - polytrauma KW - pigs KW - local inflammation KW - extremity KW - hematoma KW - muscle KW - fixation Y1 - 2020 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/53136 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-531369 SN - 1664-3224 N1 - Copyright © 2020 Horst, Greven, Lüken, Zhi, Pfeifer, Simon, Relja, Marzi, Pape and Hildebrand. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. VL - 10 IS - Art. 3028 SP - 1 EP - 10 PB - Frontiers Media CY - Lausanne ER -