Article Text

PDF
The bare essentials
Disorders of the spinal cord and roots
  1. Lionel Ginsberg
  1. Correspondence to Professor Lionel Ginsberg, Department of Neurology, Royal Free Hospital, Pond Street, London NW3 2QG, UK; Lionel.Ginsberg{at}nhs.net

Statistics from Altmetric.com

Introduction

The distinctive patterns of myelopathy (disorder of the spinal cord) and radiculopathy (disorder of spinal roots) are a direct consequence of the striking anatomy of the spinal cord:

  • its near cylindrical, segmental structure of great length (42–45 cm in adults)

  • the marked proximity of ascending and descending long tracts within the confines of a narrow cross sectional area (the maximum circumference of the cervical enlargement of the cord is approximately 38 mm)

  • enclosure by meninges and vertebral column

  • vulnerable blood supply.

Having established that a patient's clinical presentation localises to the spinal cord and/or roots, clues to the pathological diagnosis emerge from the timing of the symptoms (table 1), as is usually the case in neurology.

View this table:
Table 1

Speed of onset and likely cause of myeloradiculopathy

Neuroanatomy and specific syndromes

Spinal cord

The relationships of the white matter tracts to one another and to the central grey matter are most easily appreciated in transverse section (figure 1). Within the major pathways, there is a relatively orderly somatotopic arrangement:

  • In the spinothalamic tracts, the most superficial fibres are related to the sacral dermatomes. These overlie the lumbar fibres, with thoracic still deeper in the tracts, and the cervical fibres closest to the central grey matter. Pain and temperature sensation are conveyed in the lateral spinothalamic tracts whereas touch and pressure pathways are anterior (ventral).

  • In the posterior (dorsal) columns, fibres from the lower limbs ascend medially in the gracile tracts, those from the upper limbs are lateral in the bulkier cuneate tracts. Pathways for position and touch sensation generally lie deep to those for vibration and pressure.

  • In the lateral corticospinal tracts, descending fibres to the upper limbs are medial to those to the lower limbs.

Figure 1

Transverse section of the spinal cord in the mid-cervical region. Many ascending and descending tracts have …

View Full Text

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.