1. SPINAL CORD ANATOMY

2. General Characteristics
Approx. ½ meter in length.
Varies from 1 to 1.5 cm in diameter
Enlargements:
Cervical:
C3 – T1
Lumbar region:
L1 – S2

3. General Characteristics
Conus medullaris:
Ends at about the level of L2.
Cauda equina.
Filum terminale:
Thin filament of meningeal tissue extending from conus medullaris to the coccyx.

4. Spinal Nerves 08 cervical 12 thoracic 05 lumbar 05 sacral 01 coccygeal
Numbering system

5. Plexuses
Cervical:
C1 – C4
Brachial:
C5 – T1
Lumbosacral:
L1 – S4

6. Meninges Epidural space Dura mater Subdural space Arachnoid
Tough outer layer
Subdural space
Arachnoid

7. Meninges Subarachnoid space Pia mater Contains CSF
Delicate innermost layer

8. Spinal Cord Cross-Sectional Anatomy
Central canal
Gray matter
“H”-shaped
White matter

9. Gray Matter Forms regions known as horns. Equivalent of CNS nuclei.
Posterior (dorsal) horns:
Receive incoming sensory fibers.
Anterior (ventral) horns:
Site of cell bodies of alpha motor neurons to skeletal muscle fibers.

10. Gray Matter Lateral horns:
Located only in thoracic and upper lumbar regions.
Site of cell bodies of ANS motor neurons.

11. White Matter Forms longitudinal columns (funiculi).
Consists of myelinated tracts.
Posterior (dorsal) columns.
Anterior (ventral) columns.
Lateral columns.

12. Commissures
White:
Anterior and posterior.
Gray: