HOSAM M ATEF;MD

1H

Spinal Anatomy

H 2

Overview: Gross Spinal Anatomy

• Bony elements• Spinal ligaments and joints• Intervertebral discs• Neural elements• Blood supply

Spinal Column

H 7

Vertebral Column

• 24 separate vertebrae plustwo composite vertebrae:– 7 cervical– 12 thoracic– 5 lumbar– Composites:

• Sacrum: 5 pieces• Coccyx: 4 pieces

Lumbar Vertebral Body

Spinous process

Pars Defect:Spondylolysis and Spondylolisthesis

Thoracic Vertebral Body

Spinous Process

Vertebral body

Transverse

costal facet

Vertebral costal facet

Cervical Vertebral Column

Spinous process

C1

C2

Spinal Motion Segment

Ligamentsand

Spinal Joints

PosteriorLongitudinalligament

Supraspinousligament

Interspinousligament

Ligamentumflavum

PosteriorLongitudinal

Ligament

Zygapophyseal Joints

Zygapophyseal joints

• True synovial joints:– Covered by fibrous capsule– Filled with synovial fluid– Hyaline cartilage lining bony surfaces– Innervated with nociceptive fibers

• Posterior spinal structures– Nerve root exits anterior to joint

through foramen

H 34

H

Zygapophyseal joints• Lumbar joints:

– oriented obliquely at L5-S1– Oriented increasingly more in the sagittal

plane up to thoracic levels

• Cervical joints are tilted cephalocaudad

• Joints are curved structures

HERNIATING DISC VIDEO.AVI

Spinous processes

Zygapophysealjoints

Articular pillars

Intervertebralforamina

Rib articulations

Atlanto-axialand

Atlanto-occipital Joints

H 42

Atlanto-axial and atlanto-occipital joints

• Anterior spinal structures– Nerve root exits posterior to joint– No associated neural foramen

• Do not have typical medial branch innervation

• True synovial joints

Sacroiliac Joint

Neural Elements

H 48

Spinal cord

• Begins at C1 and ends at L1-2• Transmits bilateral, segmental

spinal nerves:– 8 cervical– 12 thoracic– 5 lumbar– 5 sacral

L1

Filum terminale

Cervical expansion

Lumbar expansion

S2Cauda equina

Dura

Filum terminaleLumbar expansion

Cauda equina

Termination ofdural sac

Cervical expansion

Spinal Nerves

H 52

Spinal nerve

• Originate from a dorsal and ventral root– Roots originate intra-durally, exit

through dural root sleeve

• Give rise to dorsal and ventralprimary rami

Sympathetic Nervous System

Ventral ramus

Ventral root

Filum terminale

Dorsal root ganglion

Dorsal root

Whiterami

Grayrami

Nerve Roots

H 62

Cervical nerve roots• C5 contacts the disc in the proximal

foramen

• C6 and C7 have considerable contact with their respective discs in the middle foramen

• C8 has little contact with the C7-T1 disc

H 63

Neural foramina

• Transmit spinal nerves• First and second spinal nerves (C1,

C2) do not exit via a foramen• First neural foramen is C2-3 which

transmits the C3 spinal nerve• There are 8 cervical nerves with C8

exiting out the C7-T1 foramen

Uncovertebral joint

Uncinate process

Superiorand

inferiorarticular

processes

Foramen transversarium

Neural foramen

Disc

H 65

Numbering of spinal nerve roots• In the cervical spine, the last number

of the foramen names the exiting nerve:– C3 exits the C2-3 foramen– C7 exits the C6-7 foramen

• C8 exits the C7-T1 foramen• From T1-2 down, the first number of

the foramen names the exiting nerve:– L3 exits the L3-4 foramen

C5-6, C6-7 joints

C4, C5 and C6articular pillars

C2 and C3spinous processes

C2-3 and C3-4foramina

C4

C3

C5

C6

C8

C7C6, C7 vertebral

bodies

Dorsal Primary RamiAnd

Medial Branches

C5-6 and C6-7zygapophysealjoints

C4, C5 and C6articular pillars

C2 and C3spinous processes

C2-3 and C3-4foramina

TON

Medial branch of C3

Medial branch of C4

Medial branch of C5

Medial branch of C8

C4

C3

C5

C6

C8

C7

Intervertebral Discs

Lumbar Disc

phospholipase A2

prostaglandin E

histamine

inflammatory polypeptides

Internal Disc Disruption

Cervical Disc

Vascular Elements

Course of the Vertebral Artery

Pleura

Stellate ganglion

Vertebral artery

Subclavianartery

Posterior View of Brainstem

Basilar artery

Vertebralarteries Anterior

spinal artery

Spinal Cord Blood Supply

great radicular artery of Adamkiewicz

thoracic radicular artery

Cervical radicular arteries

L and R vertebral arteries

Ascending sacral radicular artery

Meningesof the

Brain and Spinal Cord

H87

Meninges

• The dura mater surrounds the brain and spinal cord

• The arachnoid lies just beneath the dura

• Pia mater covers and is adherent to the brain and spinal cord

• CSF flows between the arachnoid and the pia mater

Arachnoidgranulations

Dura mater

Arachnoid

Choroid plexusSubarachnoi

dspace

Pia mater

End