L5 Nerve Root Compression Research Articles

The Role of Capsaicin-Sensitive Primary Afferents in Experimental Sciatica Induced by Disc Herniation in Rats

The topical capsaicin treatment of the sciatic nerve, which was proved to destroy capsaicin-sensitive primary afferent (CSPA) fibers, was performed to determine the effect on decreases in paw withdrawal mechanical threshold (PWMT) and changes in spatial expression pattern of spinal c-Fos protein induced by the direct compression of L5 nerve root with autologous disc. To investigate the role of CSPA fibers in the development of mechanical hyperalgesia in the new sciatica model. To date, CSPA fibers have been shown to be involved in development of thermal hyperalgesia in various pain models. But the controversy still exists as to whether CSPA fibers are involved in the development of mechanical hyperalgesia in different pain models. To our best knowledge, the role of CSPA in sciatica was not investigated. Therefore, the present study was designed to determine the role of CSPA fibers in the newly developed sciatica model. All surgeries were performed in Sprague-Dawley rats. PWMT was measured at the different time points postsurgery and presurgery. The changes in spatial expression pattern of c-Fos protein in the spinal cord were also determined at 3 weeks when PWMT decreased to the peak. The pretreatment with capsaicin produced a complete prevention of mechanical hyperalgesia induced by disc compression. The direct compression of L5 nerve root produced an obvious expression of Fos-like immunoreactivity neurons in the dorsal horn of the spinal cord, which was significantly decreased by pretreatment with capsaicin. We conclude that CSPA fibers, which mainly terminated in superficial layers of dorsal horn, may play a key role in mechanical hyperalgesia in the new sciatica model.

Polysegmental innervation of the medial paraspinal lumbar muscles

A retrospective analysis was performed in a nine month period of the electrophysiological data, imaging and clinical findings of patients with monoradicular disc herniation compressing either the L5 or the S1 nerve root. The primary purpose of the analysis was to determine the distribution of pathological spontaneous activity in the medial paraspinal muscles on electromyographic examination in monoradicular L5 and S1 nerve root compression syndromes. Anatomically, the medial paraspinal muscles receive their innervation from a single root while the iliocostalis muscles and the longissimus muscle are thought to be innervated by multiple nerve roots. In the analysis, in single nerve root lesion of the L5 or S1 nerve root, electromyography of the medial paraspinal muscles revealed pathological spontaneous activity one to three vertebrae cranial to the disc herniation with extension to the opposite side of the lesion. In conclusion, the medial paraspinal muscles might be thought to be innervated by one single nerve root on anatomical studies, electrophysiologically the extension of axonal lesion signs of one single lumbar nerve root is much broader. The widespread distribution of the L5 and S1 nerve root must be taken into consideration on electromyographic examination of the medial paraspinal muscles.

Migration of lumbar disc herniation: An unusual case

We illustrate a patient with a migrating lumbar disc fragment that caused a change in radicular symptoms from the L3 nerve root on one side to the L5 nerve root on the contralateral side, documented by magnetic resonance imaging (MRI). Our patient presented with 3 months of L3 pain on the right side with sensory and motor changes. Over a 24-hour time period, the right leg pain disappeared and he developed left leg pain attributable to left L5 nerve root compression. Investigation with MRI revealed an epidural mass, which was hypointense on Tl-weighted and T2-weighted images that had migrated, initially compressing the right L3 nerve root, to now compress the left L5 nerve root. The patient did not wish to pursue surgery. Disc fragment migration patterns are discussed. We conclude that extruded disc fragments may migrate distant from their initial origin.

Effect of Yiqi Huayu recipe on peanut agglutinin-binding molecules and Schwann's cells in rats after lumbar nerve root compression

To study the effect of Yiqi Huayu Recipe on peanut agglutinin-binding molecules (PNA-BMs) and Schwann's cells (Sc) of the neuromuscular junction after L5 nerve root compression in rats. The rats were given Yiqi Huayu Recipe at the 10th, 20th, 30th and 60th day after L5 nerve root compression. Using immunohistochemistry and confocal laser scanning techniques, we observed the distributions of PNA-BMs and S-100 in the soleus muscle. The overlap area of PNA-BMs and S-100 was measured with NIH image technique. The extracellular matrix (ECM) recognized by PNA played an important role in guiding the sprouting and extending of the Schwann's cells. The agglomeration, sprouting and extension of the terminal Sc and the overlap area of Sc with PNA-BMs in the Yiqi Huayu Recipe group were better than those in the control group. Yiqi Huayu Recipe can promote the growth of ECM and Schwann's cells and accelerate the nerve regeneration process.

Altered function of lumbar nerve roots in patients with transitional lumbosacral vertebrae.

A retrospective study was conducted on the preoperative neurologic symptoms of patients with lumbar herniated discs. To evaluate the possibility that the muscle innervation pattern and the sensory dermatomes of lumbar nerve roots are altered when a lumbosacral transitional vertebra is present. In 1962, McCulloch et al suggested with intraoperative recordings that the innervation pattern of the lumbar nerve roots may be altered when a lumbosacral transitional vertebra is present. However, this result was not repeated in the study by Young et al in 1983. We retrospectively reviewed the charts of 62 consecutive patients who underwent microdiscectomy for lumbar herniated discs. Lumbarized S1 vertebra was present in 10 of 62 patients (16%). Among these 10 patients, 8 had herniated discs at L5-S1 compressing the S1 nerve root. In the 52 normally configured patients, 22 had herniated discs at L5-S1 compressing the S1 nerve root, and 15 had herniated discs at L4-L5 compressing the L5 nerve root. The preoperative neurologic symptoms caused by the S1 nerve root compression in the patients with lumbarized S1 vertebrae were compared with the symptoms caused by either L5 or S1 nerve root compression in the patients with normal configuration. The distribution of motor weakness caused by the S1 nerve root compression was significantly different between the patients with lumbarized S1 and those with the normal configuration. The motor weakness caused by the S1 root compression in the patients with lumbarized S1 was similar to that of the L5 nerve root compression in the normal configuration. Analysis of sensory symptoms showed similar results. Our findings suggest that the function of lumbosacral nerve roots is altered in patients with lumbarized S1 so that the S1 nerve root serves the usual function of the L5 nerve root.

Effect of Yiqi Huayu Recipe on regeneration process after L5 nerve root compression in rats

To study the effect of Yiqi Huayu Recipe on neurons in neuromuscular junction after L5 nerve root compression in rats. By using immunohistochemistry, confocal laser scanning techniques and protein gene product 9.5 as a neuronal marker, the motor endplates were visualized with fluorescein-conjugated alpha-BTX. The effect of Yiqi Huayu Recipe on nerve terminals of neuromuscular junction at 10, 20, 30, 60 days after L5 nerve root compression was observed in rat soleus muscles during regeneration. The overlap areas of terminals and endplates were measured with NIH image technique. As for the aggregates, sprouts, extension of nerve terminal during regeneration, the connecting speed and range of nerve terminal with endplates, as well as the reformation of neuromuscular junctions during regeneration, Yiqi Huayu Recipe group was better than that of the control group. Yiqi Huayu Recipe can promote the hyperplasia of neurons and enhance the regeneration function. It also can accelerate the neuromuscular junction reformation and shorten the process of regeneration.

A Case of Localized Ossification of the Posterior Longitudimal Ligament in the Lumbar Spine

A female, aged 27 years, was admitted to our hospital complaining of a radiating pain in the left leg. X-ray findigs showed the localized ossification situated at the posterior margin of the L4-5 vertebral body. On myelography posterior protrusion at L4-5 and L5-S1 intervertebral space were found. Her clinical signs seem to arisen from L5 nerve root compression due to the bony fragment at L4-5.Laminectomy has been carried out. Bony fragment compressed L5 nerve root and dura mater posteriorly at the posterior site of the L4 vertebral body, and large protruded disc was found at L5-S1. Histologically, the excised bony fragment showed metaplastic ossification of the posterior longitudinal ligament.