15. Back and Nervous System Flashcards
(39 cards)
What do the sclerotomes form?
The sclerotome forms the vertebrae and the rib cartilage and part of the occipital bone.
What do the myotome form?
The myotome forms the musculature of the back, the ribs and the limbs.
What do the syndetome form?
The syndetome forms the tendons.
What do the dermatome form?
The dermatome forms the skin on the back.
Where does the nucleus pulposus derive from?
From the notochord.
How many cervical vertebrae are there? How many of them are atypical?
Seven cervival vertebrae and the first 2 are atypical.
What passes throught the transverse foramina?
Vertebral artery and vein.
Describe the Atlas.
It is the first cervical vertebra (C1). It has no body and leaves a space to accommodate the dens of the second cervical vertebra.
Describe the Axis.
It is the second vertebra (C2). It has a tooth-shaped process, the dens (odontoid process), which articulates with the atlas as a pivot joint. Movement at this joint allows lateral rotation of the head.
How many thoracic vertebrae are there?
There are 12.
How many lumbar vertebrae are there?
5 of them L1 to L5.
How many sacral vertebrae are there?
5 of them S1 to S5 which are fused together.
What is the most common route of a herniation ?
It is almost always in a posterolateral direction, passing through a rupture of the anulus fibrosus. The herniated nucleus often comes to lie in the intervertebral formaen where it may compress a spinal nerve.
Describe an intervetebral disk.
Each disk has an outer portion called the anulus fibrosus, which is composed of fibrocartilage and fibrous connective tissue, and an inner portion, the nucleus pulposus, which is semigelatinous fluid with very few, if any, cells.
Which ligament reinforces the intervertebral disk anteriorly and anterolaterally?
The anterior longitudinal ligament.
Which ligament reinforces the intervertebral disk posteriorly?
The posterior longitudinal ligament. There is no reinforcement of the posterolateral side.
What passes through the intervertebral foramen?
The spinal nerve.
What type of nerves does the dorsal root contain?
It contains sensory nerve fibers with their cell bodies in the dorsal root ganglion.
What type of nerves does the ventral root contain?
It contains motor nerve fibers with their cell bodies in the gray matter of the spinal cord.
What does the dorsal ramus innervate?
The skin of the back, the deep back muscles, and the zygopohyseal joints.
What does the ventral ramus innervate?
The anterior and lateral portions of the body wall and the limbs.
At what level is lumbar puncture typically performed and what anatomical structure can we use to guide?
It is performed at the L4-L5 interspace. The top of the iliac crest marks the level of the L4 vertebra.
What are all the layers that the needle passes through in a lumbar puncture?
10 layers: Skin, Superficial fascia, Deep fascia, Supraspinous ligament, Interspinous ligament, Interlaminar space, Epidural space, Dura, Arachnoid, Subarachnoid.
Which space contains the cerebrospinal fluid?
The subarachnoid space.
