Download Spinal cord

Neuroanatomy
1.gray′s anatomy thirty-ninth edition
2.Neuroanatomy for medical student
by;yousef sadeghi
3.Clinical neuroanatomy R.Snell
4.The human nervous system BARR
J.kiernan
5.Textbook of human neuroanatomy
I.singh
Spinal cord
Spinal Cord
Same Meningeal Layers as the Brain 
About 45cm long 
Diameter of 1 cm. 
Root filaments
Dorsal
Ventral
Pia mater
Arachnoid mate
Mixed spinal
nerve
Dura mater
Meninges of Vertebra and Spinal
Cord
Cross-Sectional Anatomy of the Spinal
Cord
Central area of gray matter shaped like a butterfly and 
surrounded by white matter in 3 columns
Gray matter = neuron cell bodies with little myelin 
White matter = myelinated axons 
Spinal Nerve Roots and Plexuses
Spinal cord
31 nerves connecting 
the spinal cord and
various body regions.
8 paired cervical nerves 
12 paired thoracic 
nerves
5 paired lumbar nerves 
5 paired sacral nerves 
1 pair of coccygeal 
nerve
Structure of the Spinal Cord
white matter
(axons)
meninges
pia •
arachnoid •
dura •
gray matter (cell bodies)
• dorsal (posterior) horn
• ventral (anterior) horn
denticulate
ligament
dorsal
rootlets
ventral
rootlets
dorsal root
(spinal) ganglion
subarachnoid
space
(CSF)
Moore’s COA5 2006
ventral root
• dura
• arachnoid
• pia
meninges
spinal nerve
• dorsal primary ramus
• ventral primary ramus
Rami of Spinal Nerves
Notice the branching and merging of nerves 
in this example of a plexus
Gray Matter
Posterior horns contain 
interneurons.
Anterior horns contain some 
interneurons as well as the cell 
bodies of motor neurons.
These cell bodies project their axons via the 
ventral roots of the spinal cord to the skeletal
muscles.
The amount of ventral gray matter at a given 
level of the spinal cord is proportional to the
amount of skeletal muscle innervated.
Downloaded from: Gray's Anatomy (on 17 August 2007 07:22 PM)
© 2007 Elsevier
Downloaded from: Gray's Anatomy (on 17 August 2007 07:22 PM)
© 2007 Elsevier