The Spine Journal
Volume 4, Issue 3 , Pages 275-280, May 2004

Sensory innervation of the lateral portion of the lumbar intervertebral disc in rats☆

  • Yasuchika Aoki, MD

      Affiliations

    • Department of Orthopedic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City 260-8670, Japan
    • Corresponding Author InformationCorresponding author. Department of Orthopedic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba City 260-8670, Japan. Tel.: +81-43-226-2117; fax: +81-43-226-2116.
    • ,
  • Yuzuru Takahashi, MD, PhD

      Affiliations

    • Department of Orthopedic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City 260-8670, Japan
    • ,
  • Kazuhisa Takahashi, MD, PhD

      Affiliations

    • Department of Orthopedic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City 260-8670, Japan
    • ,
  • Tanemichi Chiba, MD, PhD

      Affiliations

    • Department of Neurobiology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City 260-8670, Japan
    • ,
  • Masahiro Kurokawa, MD

      Affiliations

    • Department of Orthopedic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City 260-8670, Japan
    • ,
  • Tomoyuki Ozawa, MD

      Affiliations

    • Department of Orthopedic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City 260-8670, Japan
    • ,
  • Hideshige Moriya, MD, PhD

      Affiliations

    • Department of Orthopedic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City 260-8670, Japan

Received 21 March 2003; accepted 2 October 2003.

Abstract 

Background context

An annular tear extending to the outer one-third of the annulus is thought to be one of the causes of low back pain. However, some patients have bilateral low back symptoms, even if the annular tear is localized in the lateral disc. Because nociceptive information from the lateral disc is transmitted by the dorsal root ganglion (DRG) neurons innervating the lateral disc, we investigated the distribution of the DRG neurons innervating the lateral portion of the disc.

Purpose

To clarify the distribution and pathway of the DRG neurons innervating the lateral portion of the L5–L6 disc in rats.

Study design/setting

Using the retrograde tracing method, we studied the innervation pattern of the lateral portion of the L5–L6 intervertebral disc in rats.

Methods

The retrograde transport of Fluoro-Gold (F-G; Fluorochrome, Denver, CO) was used in 22 rats. Subjects included a nontreated group (n=16) and a sympathectomized group (n=6). Seven days after the application of F-G crystals to the left lateral portion of the L5–L6 disc, bilateral T12–L6 DRGs were observed by fluorescent microscopy.

Results

In the nontreated group, of all the F-G–labeled neurons, 93.1% were present in the left DRGs and 6.9% were in the right DRGs. The number of labeled neurons was largest in the left L2 DRGs. In the sympathectomized group, the numbers of labeled neurons in the T13, L1 and L2 DRGs were significantly lower than the numbers in the nontreated group.

Conclusion

Results of this study indicate that DRG neurons innervating the lateral portion of the disc are distributed mainly in the ipsilateral side but also in the contralateral side. The DRG neurons in T13, L1 and L2 innervate the lateral portion of the L5–L6 disc through the paravertebral sympathetic trunks.

Keywords:  Intervertebral disc, Dorsal root ganglion (DRG), Laterality, Discogenic pain, Low back pain, Retrograde tracing, Sympathetic trunks, Sensory fibers

To access this article, please choose from the options below

Login to an existing account or Register a new account.

  • Purchase this article for 31.50 USD (You must login/register to purchase this article)

    Online access for 24 hours. The PDF version can be downloaded as your permanent record.

  • Subscribe to this title

    Get unlimited online access to this article and all other articles in this title 24/7 for one year.

  • Claim access now

    For current subscribers with Society Membership or Account Number.

  • Visit SciVerse ScienceDirect to see if you have access via your institution.
 

☆ FDA device/drug status: not applicable.This work was supported in whole or in part by the Japanese Society for the Promotion of Science under Grant 1457 1358. Nothing of value received from a commercial entity related to this research.

PII: S1529-9430(03)00554-0

doi:10.1016/j.spinee.2003.10.005

The Spine Journal
Volume 4, Issue 3 , Pages 275-280, May 2004

Article Tools

* Image Usage & Resolution