Vertebral Column Flashcards
Vertebral column
33 vertebrae - 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 4 coccyx
Kyphosis
Original spinal curvature since birth; maintained in the thoracic and sacral region; primary curvature; and concave anteriorly (outwards)
Lordosis
New curvature; found in the cervical and lumbar region; secondary curvature; concave posteriorly (inwards)
Cervical lordosis
Secondary curvature acquired when the infant can support the weight of the head
Lumbar lordosis
Secondary curvature acquired when the infant walks and supports his/her own weight
Excessive kyphosis
Humpback, hunchback
Excessive lordosis
Hollowback, swayback
Scoliosis
Abnormal lateral curvature of the spine
Which vertebrae contain transverse foramen?
Cervical vertebrae
Which vertebrae bear facets for the ribs?
Thoracic vertebrae
Which vertebrae have a massive body?
Lumbar vertebrae - intended to support more weight
What is the sacrum composed of?
5 fused vertebrae
What is the coccyx composed of?
4 vertebrae, with the last 3 often fused into a single bone
What does the coccyx lack?
Vertebral arches and a vertebral canal
Cervical rib
Extra rib articulating with C7. The presence of a cervical rib can cause a form of thoracic outlet syndrome (compression of the brachial plexus or subclavian Vs)
Lumbar rib
Extra rib articulating with L1
Sacralization
L5 is partially incorporated into the sacrum
Lumbarization
S1 is separated from the rest of the sacrum
Intervertebral discs
Joints of the vertebral bodies
What do IV discs contain?
IV discs are secondary cartilaginous joints designed for weight-bearing and strength. It contains an annulus fibrosis, which is an outer fibrous part, composed of concentric lamellae of fibro-cartilage, as well as a nucleus pulposus, which is a gelatinous central mass.
Herniated disc
A protrusion of the nucleus pulposus into or through the annulus fibrosis
Z discs
Joints of the vertebral arches
Where are Z discs found and what do they do?
Z discs are found between superior and inferior articular processes/facets. They allow for some gliding and sliding movement.
Anterior longitudinal ligament
Connects anterior vertebral bodies and IV discs
Posterior longitudinal ligament
Connects posterior vertebral bodies and IV discs
LIgamentum flavum
Connects adjacent vertebral laminae
Interspinous ligament
Connects vertebral spines
Supraspinous ligament
Connects vertebral spine tips
Intertransverse ligament
Connects vertebral transverse processes
Ligamentum nuchae
A strong triangular ligament at the back of the neck. It is essentially the direct continuation of the supraspinous ligament
Laminectomy
The surgical excision of one or more spinous processes and the adjacent supporting vertebral laminae in a particular region of the vertebral column
The spinal cord begins as…
A continuation of the medulla oblongata (the caudal part of the brainstem)
The spinal cord ends as…
The conus medullaris
Where does the spinal cord lie?
It lies in the vertebral canal and it extends from the foramen magnum to the level of L1 or L2 (in adults) or L3 (in children)
Cauda equina
The loose bundle of spinal nerve roots arising from the lumbosacral enlargement and the conus medullaris
Grey matter of the spinal cord
Cell bodies, soma
White matter of the spinal cord
Axons, tracts
Cervical enlargement of the spinal cord
From C5 to T1, innervates the upper limbs
Lumbosacral enlargement of the spinal cord
From L1 to S3, innervates the lower limbs
Arterial supply of the spinal cord
One anterior spinal artery and two posterior spinal arteries
Venous drainage of the spinal cord
Drain into an extensive internal vertebral plexus in the extradural (epidural) space of the vertebral canal
Dura mater
Forms a tough, outer protective layer. Extends from the margin of the foramen magnum to the level of S2. Has a subdural and an epidural space
Arachnoid mater
Very thin and delicate, contains subarachnoid space
Subarachnoid space
A wide space between the pia and arachnoid mater that contains CSF, ends opposite S2
Pia mater
Close to the spinal cord and continues as the filum terminale; contains lateral extensions called denticulate ligaments
Filum terminale
A thin and delicate ligament which extends from the conus medullaris to the coccyx. It is composed primarily of pia mater. It has two parts - pial and dural
Denticulate ligament
A toothed ligament formed by the pia mater that extends laterally and pierces the arachnoid to be attached to the dura between two spinal roots
Lumbar puncture
A spinal tap; the passage of a needle into the subarachnoid space between L3 and L4 to obtain CSF or to inject treatments
List the arrangement of structures in the vertebral canal (from the outside to inside)
Epidural space Dura mater Subdural space Arachnoid space Subarachnoid space with CSF Pia mater Spinal cord and cauda equina
Spinal nerves
There are 31 spinal nerves, 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccyx
Anterior (ventral) nerve roots
Consist of motor (efferent) fibers
Posterior (dorsal) nerve roots
Consist of sensory (afferent) fibers
Mixed spinal nerve
The posterior and the anterior nerve roots unite at around the intervertebral foramen which divides into two rami; contain both sensory and motor fibers
Dorsal (posterior) rami
Small ramus that conveys motor and sensory information to the skin and the intrinsic back skeletal muscles
Ventral (anterior) rami
Large ramus that conveys motor and sensory information to the skin and the skeletal muscles of the neck, limbs, and trunk