Measurement of the local pressure of the intervertebral foramen and the electrophysiologic values of the spinal nerve roots in the vertebral foramen

• Published in: Spine (Philadelphia, Pa. 1976) Vol. 31; no. 26; p. 3076
• Main Authors: Morishita, Yuichiro, Hida, Shinichi, Naito, Masatoshi, Arimizu, Jun, Matsushima, Ushio, Nakamura, Atsuhiko
• Format: Journal Article
• Language: English
• Published: United States 15.12.2006
• Subjects: Action Potentials - physiology; Adolescent; Adult; Aged; Aged, 80 and over; Electrodiagnosis; Female; Humans; Intervertebral Disc - physiopathology; Intervertebral Disc Displacement - complications; Intervertebral Disc Displacement - physiopathology; Lumbar Vertebrae; Male; Middle Aged; Nerve Compression Syndromes - etiology; Nerve Compression Syndromes - physiopathology; Posture; Pressure; Spinal Nerve Roots - physiopathology; Spinal Stenosis - complications; Spinal Stenosis - physiopathology
• ISSN: 1528-1159
• DOI: 10.1097/01.brs.0000249559.96787.d4

The intraoperative findings of the local pressure of the intervertebral foramen and the electrophysiologic values of the spinal nerve roots were evaluated. To investigate the neurophysiologic changes of the spinal nerve roots in the vertebral foramen. As far as we know, few reports have so far described the neurophysiologic changes of the spinal nerve roots in the vertebral foramen. The local pressure of the intervertebral foramen was continuously measured while the lumbar spine posture was changed in 66 vertebral foramens. In addition, 20 L5 nerve roots were electrophysiologically evaluated using the compound muscle action potentials (CMAPs) from tibialis anterior (TA) muscle after L5 nerve root stimulation. The local pressure of the intervertebral foramen was significantly increased during lumbar spine extension (P < 0.001); moreover, the latency and amplitude of the CMAPs both significantly deteriorated in line with the increasing local pressure. Our findings suggested that a double compression of the nerve root exists in lumbar spinal stenosis with lumbar spine extension, which includes the spinal canal and the vertebral foramen.