Clinical Anatomy Skeletal System 3 > CONTENTS OF VERTEBRAL CANAL > Flashcards

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What are the contents of the Vertebral canal? (12)

1. Spinal Cord
2. Spinal nerve roots
3. Spinal root ganglia(swelling in the dorsal root)
4. Internal vertebral plexus of veins
5. Fat
6. Meninges
7. CSF
8. Radicular arteries
9. Anterior and posterior spinal arteries and veins
10. Posterior longitudinal ligament
11. Tectorial membrane
12. Transverse, cruciform, and alar ligament


What is Dura Mater?

1. Outer most part of the meninges
2. Forms a sac (Dural sac )
3. Starts at the Foramen Magnum and ends at S2 vertebra
4. The spinal dural sac is pierced by the spinal nerves and is anchored inferiorly to the coccyx by the filum terminale externum


What is the Arachnoid Mater?

1. Is not attached to the Dura Mater
2. Held against the inner surface of the dura mater by the pressure of the CSF


What is the Pia Mater?

1. Inferior to the conus medullaris, the pia continues as the filum terminale
2. The brain and spinal
cord are intimately covered on their outer surface by the innermost meningeal layer, a delicate, transparent covering


What is the Filum terminale?

1. The filum terminale
serves as an anchor for the inferior ends of the spinal cord and dural sac

*Filum terminale Internum: Pierces the caudal end of the dural sac, which acquires a layer of dura mater and becomes Filum terminale externum or coccygeal ligament


What are Denticulate ligaments?

1. Prevent excessive displacement of the spinal cord
2. Lateral extensions of pia mater
3. Attach to the inner surface of dura mater

*About 22 extensions that attach to the dura mater


What are the 2 spaces in Spinal Meninges?

1. Epidural space
2. Subarachnoid space


What is the Epidural Space?

1. Loose fatty connective tissue
2. Internal vertebral venous plexus


What is the Subarachnoid Space?

1. Contains CSF, spinal nerve roots, and spinal root ganglia
2. Between the arachnoid and pia, is a real space that contains CSF, trabecular cells, cerebral arteries, and bridging superior cerebral veins that drain into the superior sagittal sinus
3. Also, contains Aracnoid trabeculae, denticulate ligaments, Radicular arteries, and the anterior/posterior spinal arteries and veins


What is the Lumbar cistern?

1. From L2 to S2 vertebral level
2. Lumbar puncture (site to take sample of CSF)

*Lumbar spinal puncture (spinal tap) is performed with the patient leaning forward or lying on the side with the back flexed

*Flexion of the vertebral column facilitates insertion of the needle by spreading the laminae and spinous processes
apart, stretching the ligament flava

*The needle is inserted in the midline between the spinous processes of the L3 and L4 (or the
L4 and L5) vertebrae

*Lumbar tap NEVER above the 3rd Lumber vertebrae


Where does the Spinal Cord extend from?

1. Extends from the Foramen magnum to L1/L2 IV disc (medullary cone)

*Lumbar tap NEVER above the 3rd Lumber vertebrae


What are the 2 parts that the Spinal Cord expands?

1. Cervical enlargement (C4 to T1 spinal cord segments)
2. Lumbar enlargement (T12 to L4 spinal cord segments)


What are the 2 substances in a Spinal Cord?

1. White Substance
2. Gray substance


What is Gray Substance?

1. Grey substance creates two columns that are joined together by grey matter (creating a H-like structure)
2. Contains Neuronal Body that have in intercalated neurons in the Posterior Horn
3. The Anterior Horn contains somatic motor (efferent) neurons


What is Visceral Motor (efferent) neurons?

1. Part of the Gray substance
2. Can be sympathetic (Lateral horn: T1 to L2) or parasympathetic (Intermediate zone: S2 to S4)
3. Sensory (afferent) can be somatic or visceral in the Dorsal Root Ganglia

*Visceral efferent (motor) fibers that stimulate smooth
(involuntary) muscle in the walls of blood vessels and organs,
modified cardiac muscle


What are the components for the formation of spinal nerves?

1. Dorsal root (sensory: afferent)
2. Ventral root (Somatic and Visceral) that contains pregangloioic fibers
3. Spinal nerves (Sensory, somatic, and visceral)


What is Visceral motor fibers in Spinal Nerves?

1. Contains Preganglionic sympathetic (White rami communicans )
1. Contains Postganglionic sympathetic (Gray rami communicans)

*Gray rami enters back into the spinal nerve


What is posterior rami?

1. Supply nerve fibers to synovial joints of the vertebral column, deep muscles of the back, and the overlying skin


What is anterior rami?

1. Supply nerve fibers to the much larger remaining area, consisting of anterior and lateral regions of
the trunk and the upper and lower limbs arising from them


What is a Dermatome?

1. Area of skin that is supplied by the right and left dorsal roots of the spinal cord


What is the relationship of spinal nerves to the cervical region?

1. Spinal nerves exit through the IV foramen ABOVE the correspondingly numbered vertebra

*C8 exist because of the slope and is between C7 and T1 vertebrae


What is the relationship of spinal nerves to the Cervicothoracic junctions and down?

1. Spinal nerves exit through the IV foramen BELOW the corresponding numbered vertebra


What is the most common site for herniation of the nucleus pulposus?

1. L4/L5 or L5/S1 IV discs are common for herniations

*Herniated nucleus pulposus compresses the nerve root numbered one inferior to the IV disc