Relevant Anatomic and Morphological Measurements of the Rat Spine: Considerations for Rodent Models of Human Spine Trauma.

Study Design: Basic science study measuring anatomical features of the cervical and lumbar spine in rat with normalized comparison with the human.

Objective: The goal of this study is to comprehensively compare the rat and human cervical and lumbar spines to investigate whether the rat is an appropriate model for spine biomechanics investigations.

Summary Of Background Data: Animal models have been used for a long time to investigate the effects of trauma, degenerative changes, and mechanical loading on the structure and function of the spine.

Whole-body Vibration at Thoracic Resonance Induces Sustained Pain and Widespread Cervical Neuroinflammation in the Rat.

Background: Whole-body vibration (WBV) is associated with back and neck pain in military personnel and civilians. However, the role of vibration frequency and the physiological mechanisms involved in pain symptoms are unknown.

Questions/purposes: This study asked the following questions: (1) What is the resonance frequency of the rat spine for WBV along the spinal axis, and how does frequency of WBV alter the extent of spinal compression/extension? (2) Does a single WBV exposure at resonance induce pain that is sustained? (3) Does WBV at resonance alter the protein kinase C epsilon (PKCε) response in the dorsal root ganglia (DRG)? (4) Does WBV at resonance alter expression of calcitonin gene-related peptide (CGRP) in the spinal dorsal horn? (5) Does WBV at resonance alter the spinal neuroimmune responses that regulate pain?

Methods: Resonance of the rat (410 ± 34 g, n = 9) was measured by imposing WBV at frequencies from 3 to 15 Hz.

Upregulation of BDNF and NGF in cervical intervertebral discs exposed to painful whole-body vibration.

Study Design: In vivo study defining expression of the neurotrophins, brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), in cervical intervertebral discs after painful whole-body vibration (WBV).

Objective: The goal of this study is to determine if BDNF and NGF are expressed in cervical discs after painful WBV in a rat model.

Summary Of Background Data: WBV is a possible source of neck pain and has been implicated as increasing the risk for disc disorders.

Whole body vibration induces forepaw and hind paw behavioral sensitivity in the rat.

Whole body vibration (WBV) has been linked to neck and back pain, but the biomechanical and physiological mechanisms responsible for its development and maintenance are unknown. A rodent model of WBV was developed in which rats were exposed to different WBV paradigms, either daily for 7 consecutive days (repeated WBV) or two single exposures at Day 0 and 7 (intermittent WBV). Each WBV session lasted for 30 min and was imposed at a frequency of 15 Hz and RMS platform acceleration of 0.

ProDisc cervical arthroplasty does not alter facet joint contact pressure during lateral bending or axial torsion.

Study Design: A biomechanical study of facet joint pressure after total disc replacement using cadaveric human cervical spines during lateral bending and axial torsion.

Objective: The goal was to measure the contact pressure in the facet joint in cadaveric human cervical spines subjected to physiologic lateral bending and axial torsion before and after implantation of a ProDisc-C implant.

Summary Of Background Data: Changes in facet biomechanics can damage the articular cartilage in the joint, potentially leading to degeneration and painful arthritis.

Facet joint contact pressure is not significantly affected by ProDisc cervical disc arthroplasty in sagittal bending: a single-level cadaveric study.

Background Context: Total disc arthroplasty is a motion-preserving spinal procedure that has been investigated for its impact on spinal motions and adjacent-level degeneration. However, the effects of disc arthroplasty on facet joint biomechanics remain undefined despite the critical role of these posterior elements on guiding and limiting spinal motion.

Purpose: The goal was to measure the pressure in the facet joint in cadaveric human cervical spines subjected to sagittal bending before and after implantation of the ProDisc-C (Synthes Spine Company, L.

The potential for salmon fibrin and thrombin to mitigate pain subsequent to cervical nerve root injury.

Nerve root compression is a common cause of radiculopathy and induces persistent pain. Mammalian fibrin is used clinically as a coagulant but presents a variety of risks. Fish fibrin is a potential biomaterial for neural injury treatment because it promotes neurite outgrowth, is non-toxic, and clots readily at lower temperatures.

Contact pressure in the facet joint during sagittal bending of the cadaveric cervical spine.

The facet joint contributes to the normal biomechanical function of the spine by transmitting loads and limiting motions via articular contact. However, little is known about the contact pressure response for this joint. Such information can provide a quantitative measure of the facet joint's local environment.

Metabotropic glutamate receptor-5 and protein kinase C-epsilon increase in dorsal root ganglion neurons and spinal glial activation in an adolescent rat model of painful neck injury.

There is growing evidence that neck pain is common in adolescence and is a risk factor for the development of chronic neck pain in adulthood. The cervical facet joint and its capsular ligament is a common source of pain in the neck in adults, but its role in adolescent pain remains unknown. The aim of this study was to define the biomechanics, behavioral sensitivity, and indicators of neuronal and glial activation in an adolescent model of mechanical facet joint injury.

Spinal microglial proliferation is evident in a rat model of painful disc herniation both in the presence of behavioral hypersensitivity and following minocycline treatment sufficient to attenuate allodynia.

Although spinal glia acquire a reactive profile in radiculopathy, glial cell proliferation remains largely unstudied. This study investigated spinal glial proliferation in a model simulating painful disc herniation; the C7 nerve root underwent compression and chromic gut suture exposure or sham procedures. A subset of injured rats received minocycline injections prior to injury.