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Updated: Jul 30, 2026
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Transtubular Endoscopic Posterolateral Decompression for L5-S1 Lumbar Lateral Disc Herniation
Published on: October 14, 2022
Physiologic changes of nerve root during posterior lumbar discectomy
H Matsui1, H Kitagawa, Y Kawaguchi
1Department of Orthopaedic Surgery, Toyama Medical and Pharmaceutical University, Faculty of Medicine, Japan.
Spine
|March 15, 1995
Summary
Nerve root retraction during posterior lumbar discectomy can cause ischemia, impacting blood flow and nerve function. High retraction pressure and prolonged retraction time increase the risk of nerve root injury.
Area of Science:
- Neurosurgery
- Spinal Surgery
- Nerve Physiology
Background:
- Clinical studies on nerve compression primarily focus on peripheral nerves.
- The precise risks of lumbar nerve root injury during surgery remain under-evaluated in humans.
Purpose of the Study:
- To investigate the effects of nerve root retraction during posterior lumbar discectomy.
- To assess the impact on nerve root pressure, blood flow, and electrophysiologic changes.
Main Methods:
- Monitored retraction pressure and discectomy duration in 31 patients with lumbar disc herniation.
- Measured nerve root blood flow, compound muscle action potential thresholds, and amplitudes.
- Analyzed correlations between intraoperative nerve root physiology and postoperative neurological outcomes.
Main Results:
- Nerve root blood flow decreased significantly (18-30%) at pressures around 70 g/cm², even with minimal retraction.
- Increased retraction pressure (>170 g/cm²) in 4 patients correlated with temporary sensory deterioration.
- Electrophysiologic changes indicated greater nerve root compromise in roots with sensory/motor deficits.
Conclusions:
- Nerve root ischemia is common during retraction in posterior lumbar discectomy.
- Retraction pressure and duration are identified as potential risk factors for nerve root injury.
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