Biomechanics of the Lumbosacral Nerve Roots

Comparison of Longitudinal Sciatic Nerve Movement With Different Mobilization Exercises: An In Vivo Study Utilizing Ultrasound Imaging

“…It is expected, from cadaver studies, that full extension of the cervical spine would allow a release of neural tension via the spinal cord and spinal nerve roots, 8,9,43 which potentially allows more excursion of the sciatic nerve.…”

“…19,26,27,31,44 Cervical flexion has been suggested to increase tension within the lumbar nerve roots, resulting in an unfolding of resting slack within the nerve root. 9,10,43 Cervical flexion has been shown in research involving cadavers to cause 3 to 4 mm of cranial movement of spinal nerve roots within the thoracic spine. 9 Cervical flexion has been widely advocated as an additional maneuver to the slump test to further tension the neural system, leading to neural sensitization and symptom reproduction.…”

“…9,10,43 Cervical flexion has been shown in research involving cadavers to cause 3 to 4 mm of cranial movement of spinal nerve roots within the thoracic spine. 9 Cervical flexion has been widely advocated as an additional maneuver to the slump test to further tension the neural system, leading to neural sensitization and symptom reproduction. 10,14,15,44 However, it is unclear whether the increased neural sensitization stems from an increase in neural tension, neural excursion, or both.…”

Comparison of Nonballistic Active Knee Extension in Neural Slump Position and Static Stretch Techniques on Hamstring Flexibility

“…Maitland (1 6-18) described a neural tension test (ie., slump test) in which active knee extension is performed by subjects in a sitting position while maintaining cervical and thoracolumbar flexion. This position effectively tensions the dura, spinal cord, and lumbosacral nerve roots (3). A normal response of limited knee extension and ankle dorsiflexion range of motion occurred in the flexed, or slumped posture, but full range was achieved after cervical flexion was released and the head returned to the upright position (16,17 The purpose of this study was to determine the effectiveness of nonballistic, repetitive active knee extension movements performed in a neural slump sitting position on hamstring flexibility in uninjured subjects.…”

Topographic relations between the neural and ligamentous structures of the lumbosacral junction: in-vitro investigation

“…Furthermore, the periosteal adhesion of the L5 nerve root itself, observed in several specimens, appears to be of considerable pathophysiologic importance. If one assumes an intradural course of the lumbar nerve roots of between 60 mm (L1) and 170 mm (S1), the free displacement distance of the corresponding axons described by Breig and Marions [1] is reduced by fixation to a total length of well below 300 mm. Lundborg and Rydevik [20] demonstrated in animal experiments that the extension of a peripheral nerve by as little as 8% already results in impairments of intraneuronal microcirculation.…”