Dalley, 10th Edition

131

Contents of Vertebral Canal

1 2 3

C1

1

Spinal cord

Spinal nerves:

C1

Vertebral body:

2

3

C2

4

4

C1

C3

Cervical nerves (8 pairs)

Cervical enlargement

C1

5 6

5

C4

C2

C3

C5

6

C2

7

C4

C5

C6

7

2

8

C6

Spinal cord segments/spinal nerves Cervical Thoracic Lumbar Sacral and coccygeal

C7

8

C7

1

C7

C8

T1 C8

T1

T1

T1

1

2

T2

T3

T2

3

T4

2

T5

T3

T6

4

3

T8 T7

Vertebral canal (epidural space)

T4

5

T9

4

T10

T5

T11

T12 L1

5

6

T12

Subarachnoid space

T6

L1

6

7

Thoracic nerves (12 pairs)

L3

T7

7

L3

8

T8

L4

8

L5

9

S1

T9

S1

9

S2

10

S5

Co1

T10

10

(A) Schematic, embryonic spinal cord in vertebral canal Lateral view

11

11

T11

12

12 1 2 3 4 5 1 2 3 4 5

1

T12

Lumbosacral enlargement Conus medullaris

2

3

S

T12

T10

T12

4

S

L1

5

*

T11

1

L1

2

*

3

Spinal dural sac

L1

L2

T12

C

C

Cauda equina Filum terminale internum Lumbar cistern of subarachnoid space

L2

L1

L3

Lumbar nerves (5 pairs)

*

*

L2

L4

L3

F

L3

L5

S1 L5

L4

S1

S2

(C) Sagittal MRI of child (D) Sagittal MRI of adult

S3

S4 Copyright © 2027 Wolters Kluwer. Unauthorized reproduction of the article is prohibited. Key for C and D

Sacral nerves (5 pairs)

C F S

Conus medullaris Filum terminale Spinal cord

S5

Filum terminale externum

S5

Coccygeal nerve (1 pair)

Nerve roots Spinous processes (cartilaginous in child) *

Lateral view

Anterior view

(B) Schematic, adult spinal cord in vertebral canal

FIGURE 2.45. Relationships of vertebral column, spinal cord segments, and spinal nerves and ganglia. A. At 12 weeks gestation, the spinal cord is the same length as the vertebral column. B. The relation of the spinal cord segments ( the numbered segments ) and spinal nerves and ganglia to the adult vertebral column. Greater growth of the vertebral column has made the spinal cord shorter by comparison. Now spinal nerves must descend increasingly farther within the vertebral canal to reach the intervertebral foramen by which they exit. Lumbar and sacral spinal nerves extend inferior to the level of the cord, forming the cauda equina. C. MRI of child with spinal cord terminating at level of L2/L3 IV disc. D. MRI of adult with spinal cord terminating at level of T12/L1 IV disc.