Dataset Information

Burn and thoracic trauma alters fracture healing, systemic inflammation, and leukocyte kinetics in a rat model of polytrauma.

ABSTRACT:

Background

Singular traumatic insults, such as bone fracture, typically initiate an appropriate immune response necessary to restore the host to pre-insult homeostasis with limited damage to self. However, multiple concurrent insults, such as a combination of fracture, blunt force trauma, and burns (polytrauma), are clinically perceived to result in abnormal immune response leading to inadequate healing and resolution. To investigate this phenomenon, we created a model rat model of polytrauma.

Methods

To investigate relationship between polytrauma and delayed healing, we created a novel model of polytrauma in a rat which encompassed a 3-mm osteotomy, blunt chest trauma, and full-thickness scald burn. Healing outcomes were determined at 5 weeks where the degree of bone formation at the osteotomy site of polytrauma animals was compared to osteotomy only animals (OST).

Results

We observed significant differences in the bone volume fraction between polytrauma and OST animals indicating that polytrauma negatively effects wound healing. Polytrauma animals also displayed a significant decrease in their ability to return to pre-injury weight compared to osteotomy animals. Polytrauma animals also exhibited significantly altered gene expression in osteogenic pathways as well as the innate and adaptive immune response. Perturbed inflammation was observed in the polytrauma group compared to the osteotomy group as evidenced by significantly altered white blood cell (WBC) profiles and significantly elevated plasma high-mobility group box 1 protein (HMGB1) at 6 and 24 h post-trauma. Conversely, polytrauma animals exhibited significantly lower concentrations of plasma TNF-alpha (TNF-?) and interleukin 6 (IL-6) at 72 h post-injury compared to OST.

Conclusions

Following polytrauma with burn injury, the local and systemic immune response is divergent from the immune response following a less severe singular injury (osteotomy). This altered immune response that follows was associated with a reduced capacity for wound healing.

SUBMITTER: Mangum LH

PROVIDER: S-EPMC6381742 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Publications

Burn and thoracic trauma alters fracture healing, systemic inflammation, and leukocyte kinetics in a rat model of polytrauma.

Mangum Lauren H LH Avila Joshua J JJ Hurtgen Brady J BJ Lofgren Alicia L AL Wenke Joseph C JC

Journal of orthopaedic surgery and research 20190219 1

<h4>Background</h4>Singular traumatic insults, such as bone fracture, typically initiate an appropriate immune response necessary to restore the host to pre-insult homeostasis with limited damage to self. However, multiple concurrent insults, such as a combination of fracture, blunt force trauma, and burns (polytrauma), are clinically perceived to result in abnormal immune response leading to inadequate healing and resolution. To investigate this phenomenon, we created a model rat model of polyt ...[more]

PMID: 30782193

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Dataset Information

Burn and thoracic trauma alters fracture healing, systemic inflammation, and leukocyte kinetics in a rat model of polytrauma.

Background

Methods

Results

Conclusions

Publications

Burn and thoracic trauma alters fracture healing, systemic inflammation, and leukocyte kinetics in a rat model of polytrauma.

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