title: Biomechanical studies in an ovine model of non-accidental head injury.
abstract: This paper presents the head kinematics of a novel ovine model of non-accidental head injury (NAHI) that consists only of a naturalistic oscillating insult. Nine, 7-to-10-day-old anesthetized and ventilated lambs were subjected to manual shaking. Two six-axis motion sensors tracked the position of the head and torso, and a triaxial accelerometer measured head acceleration. Animals experienced 10 episodes of shaking over 30 min, and then remained under anesthesia for 6h until killed by perfusion fixation of the brain. Each shaking episode lasted for 20s resulting in about 40 cycles per episode. Each cycle typically consisted of three impulsive events that corresponded to specific phases of the head's motion; the most substantial of these were interactions typically with the lamb's own torso, and these generated accelerations of 30-70 g. Impulsive loading was not considered severe. Other kinematic parameters recorded included estimates of head power transfer, head-torso flexion, and rate of flexion. Several styles of shaking were also identified across episodes and subjects. Axonal injury, neuronal reaction and albumin extravasation were widely distributed in the hemispheric white matter, brainstem and at the craniocervical junction and to a much greater magnitude in lower body weight lambs that died. This is the first biomechanical description of a large animal model of NAHI in which repetitive naturalistic insults were applied, and that reproduced a spectrum of injury associated with NAHI.
authors: Centre for Automotive Safety Research, The University of Adelaide, Adelaide 5005, SA, Australia. Electronic address: robert@casr.adelaide.edu.au.
authors: R W G
authors: RW
authors: Anderson
authors: Centre for Automotive Safety Research, The University of Adelaide, Adelaide 5005, SA, Australia.
authors: B
authors: B
authors: Sandoz
authors: Centre for Automotive Safety Research, The University of Adelaide, Adelaide 5005, SA, Australia.
authors: J K
authors: JK
authors: Dutschke
authors: SA Pathology, Hanson Institute Centre for Neurological Diseases, PO Box 14 Rundle Mall, Adelaide 5000, SA, Australia.
authors: J W
authors: JW
authors: Finnie
authors: School of Medical Sciences, University of Adelaide, Frome Road, Adelaide 5005, SA, Australia.
authors: R J
authors: RJ
authors: Turner
authors: SA Pathology, Hanson Institute Centre for Neurological Diseases, PO Box 14 Rundle Mall, Adelaide 5000, SA, Australia.
authors: P C
authors: PC
authors: Blumbergs
authors: SA Pathology, Hanson Institute Centre for Neurological Diseases, PO Box 14 Rundle Mall, Adelaide 5000, SA, Australia.
authors: J
authors: J
authors: Manavis
authors: School of Medical Sciences, University of Adelaide, Frome Road, Adelaide 5005, SA, Australia.
authors: R
authors: R
authors: Vink
mesh_terms: D000054:Acceleration; D000818:Animals; D001696:Biomechanical Phenomena; D006259:Craniocerebral Trauma / Q000503:physiopathology*; D006257:Head / Q000502:physiology; D006801:Humans; D023421:Models, Animal; D009068:Movement; D038642:Shaken Baby Syndrome / Q000503:physiopathology; D012756:Sheep; D034561:Sheep, Domestic; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors
keywords: Animal model; Biomechanics; Non-accidental head injury