J Korean Soc Spine Surg.  2013 Dec;20(4):210-214. 10.4184/jkss.2013.20.4.210.

Anatomical and Pathophysiological Features of Cauda Equina

Affiliations
  • 1Department of Orthopedic Surgery, Chonbuk National Univeristy School of Medicine, Biomedical Research Institute, Chonbuk National University Hospital, Jeonju, Korea. osdr2815@naver.com

Abstract

STUDY DESIGN: Review of literature on anatomical and pathophysiological features of cauda equina.
OBJECTIVES
To look into the anatomical and pathophysiological features of cauda equina and support their basic knowledge of treating cauda equina syndrome. SUMMARY OF LITERATURE REVIEW: Cauda equina has different anatomical and pathophysiological features to peripheral nerve.
MATERIALS AND METHODS
Review of literature.
RESULTS
When compressing to cauda equina, the pathophysiologic mechanism develop as follows; increasing the vascular permiablity of nerve root, intraneural edema, and subsequent blood and nutritional impairment. Nerve root injury develops through this pathophysiologic mechanism.
CONCLUSIONS
Cauda equina has an extensive ateriovenous anastomosis and guaze-like pia mater, which supply blood and neutrition to it. These anatomical features prevent it from complete cauda equina syndrome when compressing to it under arterial blood pressure.

Keyword

Cauda equina; Anatomy; Pathophysiology

MeSH Terms

Arterial Pressure
Cauda Equina*
Edema
Peripheral Nerves
Pia Mater
Polyradiculopathy

Figure

  • Fig. 1. Intradural arrangement of cauda equina. The most caudal roots (black arrow) is located in central and posterior position, and the most cephalad roots (asterix) is located in lateral and anterior position. In addition, motor fiber is located in medial and anterior to sensory fiber (Photography by Shinich Kikuchi, MD, PhD).

  • Fig. 2. Photo showing the differences between spinal nerve root (asterix) and cauda equine (black arrows). Cauda equina has no connective tissue, adipose tissue, perineurium, epineurium, and endonurium (VR: ventral root, DR: dorsal root, DRG: dorsal root ganglion, Photography by Shinich Kikuchi, MD, PhD).

  • Fig. 3. Inter- and intrafascicular arteries showing compensating coils to allow interfascicular movement (1:Radicular artery, 2: interfascicular artery, 3: intrafascicular artery). Cited from Parke WW, Watanabe R, Spine (Phila Pa 1976). 1985;10:508-15.

  • Fig. 4. Graphic complilation showing the structure of a typical lumbosacral nerve root derived from data obtained by injection studies. 1. Fas-cicular pia; 2. Inter- and intrafascicular arteries 3. Longitudinal radicular artery; 4. Large radicular vein; 5. Arteriovenous anastomosis; 6. Collateral radicular artery; 7. Gauzelike pia-arachnoid that permits percolation of CSF to assist in metabolic support. Cited from The Spine Fifth Ed. Page 49 Figure 2-42.


Reference

1. Konno S, Olmarker K, Byrod G, Rydevik B, Kikuchi S. Intermittent cauda equina compression: an experimental study of the porcine cauda equina with analyses of nerve impulse conduction properties. Spine (Phila Pa 1976). 1995; 20:1223–6.
Article
2. Konno S, Yabuki S, Sato K, Olmarker K, Kikuchi S. A model for acute, chronic and delayed graded compression of the dog cauda equina. Presentation of the gross, microscopic and vascular anatomy of the dog cauda equina and accuracy in pressure transmission of the compression model. Spine (Phila Pa 1976). 1996; 20:2758–64.
3. Olmarker K, Rydevik B. Single versus double level nerve root compression: an experimental study on the porcine cauda equina with analyses of nerve impulse conduction properties. Clin Orthop. 1992; 279:35–9.
4. Olmarker K, Rydevik B, Hansson T, Holm S. Compression-induced changes of the nutritional supply to the porcine cauda equina. J Spinal Disord. 1990; 3:25–9.
Article
5. Olmarker K, Rydevik B, Holm S. Edema formation in spinal nerve roots induced by experimental, graded compression. An experimental study on the pig cauda equina with special reference to differences in effects between rapid and slow onset of compression. Spine (Phila Pa 1976). 1989; 14:569–73.
6. Olmarker K, Rydevik B, Holm S, Bagge U. Effects of experimental graded compression on blood flow in spinal nerve roots. A vital microscopic study on the porcine cauda equina. J Orthop Res. 1989; 7:817–23.
Article
7. Olmarker K, Takahashi K, Rydevik B. Anatomy and compression-pathophysiology of the nerve roots of the lumbar spine. Anderson G.B.J., MacNeill T., editors(Eds.),. Spinal Stenosis. St. Louis: Mosby Year Book;1992. p. 77–90.
8. Orendacova J, Cızkova D, Kafka J, et al. Cauda equina syndrome. Progress in Neurobiology. 2011. 613–37.
Article
9. Yonetake T, Sekiguchi M, Konno S, Kikuchi S, Kanaya F. Compensatory Neovascularization After Cauda Equina Compression in Rats. Spine (Phila Pa 1976). 2008; 33:140–5.
Article
10. Pedowitz RA, Garfin SR, Massie JB, et al. Effects of magnitude and duration of compression on spinal nerve root conduction. Spine (Phila Pa 1976). 1992; 17:194–9.
Article
11. Takahashi K, Olmarker K, Holm S, Porter RW, Rydevik B. Double-level cauda equina compression: an experimental study with continuous monitoring of intraneural blood flow in the porcine cauda equina. J. Orthop. Res. 1993; 11:104–9.
12. Parke WW, Gammel K, Rothman RH. Arterial vascularization of the cauda equine. J Bone Joint Surg Am. 1981; 63:53–62.
13. Parke WW, Watanabe R. The intrinsic vasculature of the lumbosacral spinal nerve roots. Spine (Phila Pa 1976). 1985; 10:508–15.
Full Text Links
  • JKSS
Actions
Cited
CITED
export Copy
Close
Share
  • Twitter
  • Facebook
Similar articles
Copyright © 2024 by Korean Association of Medical Journal Editors. All rights reserved.     E-mail: koreamed@kamje.or.kr