title: Experimental Traumatic Brain Injury Induces Bone Loss in Rats.
abstract: Few studies have investigated the influence of traumatic brain injury (TBI) on bone homeostasis; however, pathophysiological mechanisms involved in TBI have potential to be detrimental to bone. The current study assessed the effect of experimental TBI in rats on the quantity and quality of two different weight-bearing bones, the femur and humerus. Rats were randomly assigned into either sham or lateral fluid percussion injury (FPI) groups. Open-field testing to assess locomotion was conducted at 1, 4, and 12 weeks post-injury, with the rats killed at 1 and 12 weeks post-injury. Bones were analyzed using peripheral quantitative computed tomography (pQCT), histomorphometric analysis, and three-point bending. pQCT analysis revealed that at 1 and 12 weeks post-injury, the distal metaphyseal region of femora from FPI rats had reduced cortical content (10% decrease at 1 week, 8% decrease at 12 weeks; p < 0.01) and cortical thickness (10% decrease at 1 week, 11% decrease at 12 weeks p < 0.001). There was also a 23% reduction in trabecular bone volume ratio at 1 week post-injury and a 27% reduction at 12 weeks post-injury in FPI rats compared to sham (p < 0.001). There were no differences in bone quantity and mechanical properties of the femoral midshaft between sham and TBI animals. There were no differences in locomotor outcomes, which suggested that post-TBI changes in bone were not attributed to immobility. Taken together, these findings indicate that this rat model of TBI was detrimental to bone and suggests a link between TBI and altered bone remodeling.
authors: 1 Department of Physiology, Anatomy and Microbiology, La Trobe University , Bundoora, VIC, Australia .
authors: Rhys D
authors: RD
authors: Brady
authors: 2 Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne , Parkville, VIC, Australia .
authors: Sandy R
authors: SR
authors: Shultz
authors: 2 Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne , Parkville, VIC, Australia .
authors: Mujun
authors: M
authors: Sun
authors: 1 Department of Physiology, Anatomy and Microbiology, La Trobe University , Bundoora, VIC, Australia .
authors: Tania
authors: T
authors: Romano
authors: 1 Department of Physiology, Anatomy and Microbiology, La Trobe University , Bundoora, VIC, Australia .
authors: Chris
authors: C
authors: van der Poel
authors: 3 Anatomy and Neuroscience, The University of Melbourne , Parkville, VIC, Australia .|4 The Florey Institute of Neuroscience and Mental Health, The University of Melbourne , Parkville, VIC, Australia .
authors: David K
authors: DK
authors: Wright
authors: 2 Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne , Parkville, VIC, Australia .
authors: John D
authors: JD
authors: Wark
authors: 2 Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne , Parkville, VIC, Australia .
authors: Terence J
authors: TJ
authors: O'Brien
authors: 1 Department of Physiology, Anatomy and Microbiology, La Trobe University , Bundoora, VIC, Australia .
authors: Brian L
authors: BL
authors: Grills
authors: 1 Department of Physiology, Anatomy and Microbiology, La Trobe University , Bundoora, VIC, Australia .
authors: Stuart J
authors: SJ
authors: McDonald
mesh_terms: D000818:Animals; D015519:Bone Density / Q000502:physiology*; D001862:Bone Resorption / Q000209:etiology* / Q000473:pathology* / Q000503:physiopathology; D000070642:Brain Injuries, Traumatic / Q000150:complications* / Q000473:pathology* / Q000503:physiopathology; D008124:Locomotion / Q000502:physiology; D008297:Male; D011897:Random Allocation; D051381:Rats; D020318:Rats, Long-Evans
keywords: bone homeostasis; bone loss; femur; fluid percussion injury; traumatic brain injury