The Structural Response of the Human Head to a Vertex Impact.

In experimental models of cervical spine trauma caused by near-vertex head-first impact, a surrogate headform may be substituted for the cadaveric head. To inform headform design and to verify that such substitution is valid, the force-deformation response of the human head with boundary conditions relevant to cervical spine head-first impact models is required. There are currently no biomechanics data that characterize the force-deformation response of the isolated head supported at the occiput and compressed at the vertex by a flat impactor.

Severity-dependent expression of pro-inflammatory cytokines in traumatic spinal cord injury in the rat.

The post-traumatic inflammatory response in acute spinal cord contusion injury was studied in the rat. Mild and severe spinal cord injury (SCI) was produced by dropping a 10 g weight from 3 and 12 cm at the T12 vertebral level. Increased immunoreactivity of TNF-alpha in mild and severe SCI was detected in neurons at 1 h post-injury, and in neurons and microglia at 6 h post-injury, with a less significant increase in mild SCI.

Downregulation of amyloid precursor protein (APP) expression following post-traumatic cyclosporin-A administration.

The aim of these studies was to assess and quantitate the effects of cyclosporin-A (CyA) on brain APP messenger RNA and neuronal perikaryal APP antigen expression following controlled focal head impact in sheep. Impact results in a significant increase in both APP mRNA and neuronal perikaryal APP antigen expression. Post-traumatic administration of CyA (intrathecal 10 mg/kg) resulted in a reduction in APP mRNA and neuronal perikaryal antigen expression.

Origin of macrophages in a kaolin-induced model of rat syringomyelia: a study using radiation bone marrow chimeras.

Study Design: Animal experimental study.

Objective: To study the origin of macrophages in a rat model of syringomyelia.

Summary Of Background Data: Syringomyelia is a clinically important condition in which a cystic cavity forms within the spinal cord.

Early expression and cellular localization of proinflammatory cytokines interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha in human traumatic spinal cord injury.

Study Design: Post-traumatic inflammatory response was studied in 11 human cases of acute spinal cord contusion injury.

Objectives: To examine the inflammatory cellular response and the immunocytochemical expression and localization of interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha in human spinal cord after contusion injury.

Summary Of Background Data: : The post-traumatic inflammatory response plays an important role in secondary injury mechanisms after spinal cord injury, and interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha are key inflammatory mediators.

Impact mechanics and axonal injury in a sheep model.

This paper describes a biomechanical study of axonal injury due to a blunt impact to the head. The aim of the experimental model was to produce axonal injury analogous to that seen in human trauma while measuring the dynamics of the impact and the subsequent kinematics of the head. These measurements were made in a way to facilitate the simulation of these experiments using the finite element method.

The role of excitotoxic injury in post-traumatic syringomyelia.

Fifty percent of patients with neurological deterioration from post-traumatic syringomyelia do not respond to treatment. Treatment failure is due in part to an incomplete understanding of the underlying aetiology. An animal model that mimics the human disease is required to investigate underlying pathophysiology and treatment options.

Altered subarachnoid space compliance and fluid flow in an animal model of posttraumatic syringomyelia.

Study Design: A histologic study of cerebrospinal fluid tracers in Sprague-Dawley rats undergoing lumboperitoneal shunt insertion in the excitotoxic animal model of posttraumatic syringomyelia (PTS).

Objectives: To determine the effects of cerebrospinal fluid (CSF) diversion from the subarachnoid space on perivascular flow (PVS) and syrinx formation in posttraumatic syringomyelia.

Summary Of Background Data: In an animal model of PTS, fluid enters syringes from the subarachnoid space via perivascular spaces.

Fluid flow in an animal model of post-traumatic syringomyelia.

More than a quarter of patients with spinal cord injury develop syringomyelia, often with progressive neurological deficit. Treatment options remain limited and long-term failure rates are high. The current poor understanding is impeding development of improved therapies.

Camel racing: a new cause of extradural haemorrhage in Australia.

Camel racing is a relatively new sport in Australia. A 52 year old woman fell from her camel during a country race. Although she was wearing an approved equestrian helmet, she suffered a skull fracture and a life-threatening extradural haematoma.

Ventriculoperitoneal shunt failure as a secondary complication of ovarian hyperstimulation syndrome. Case report.

The authors report on a patient who presented with shunt failure due to ovarian hyperstimulation syndrome (OHSS) following in vitro fertilization treatment. Shunt dysfunction was attributed to intraabdominal hypertension as a consequence of ascites. At surgery, the shunt was found to be patent.