HERNIATED DISCS & SPINAL CORD Flashcards
Describe how Spinal nerves are named in different regions of the vertebral column.
At the cervical level, spinal nerves are named on the vertebra BELOW them. At thoracic levels and below, nerves are named on the vertebra ABOVE them.
The nerve between vertebra L3 and L4 is ______. The nerve between vertebra C5 and C6 is ________.
L3 spinal nerve
C6 spinal nerve
Describe the structure and function of IV discs
Composed of inner gel-like, nucleus propulsus and the outer annulus fibrosis. Compression of the disc can occur from sitting/standing too long and elongation occurs from stretching when sleeping as water moves back into the discs. They function to cushion the vertebrae and enable mobility of vertebral column.
In what direction is the greatest potential for a herniated nucleus propulsus? What symptoms does it result in?
Herniation sites tend to occur posterior laterally due to a small posterior longitudinal ligament. Pain and deficiency in motor symptoms can occur if spinal roots are compressed.
If a herniated nucleus propulsus occurs between L1 and L2 vertebra, the ____ spinal nerve is impinged. If between C4 and C5 vertebra, the ____ spinal nerve is impinged.
L2 spinal nerve;
C5 spinal nerve
Describe what occurs in a central stenosis of the spinal cord.
The spinal nerves at the level of herniation and below are affected.
Describe Osteophytic encroachment
Osteophytes (bone spurs) directly compress the spinal nerves or indirectly do so by compressing the IV disks to cause impingement
Describe how someone can locate the level of a compressed spinal nerve from symptoms.
Work backwards from affected dermatome or myotome and refer it back to the level of a compressed nerve.
Spina bifida
Failure of vertebral arch to form correctly
Spina bifida cystica
Failure of one or more neural arches to fuse completely,
cyst-like sac protrudes out of spine
Mnemonic: “Mew-two’s tail”
Spina bifida occulta
A congenital anomaly that features a tuft of hair (and sometimes a dimple) overlying the affected skin on the lower back
Mnemonic: “Goku’s cult of Saiyans”
Meningomyelocele
Tether cord syndrome;
Protrusion of spinal cord through the meninges
Lordosis
Abnormally exaggerated lumbar vertebral curvature;
Mnemonic: “Praising pregnant women”
Kyphosis
Abnormal curvature of the thoracic vertebrae
“Hunchback syndrome”
Describe the region of the L5 dermatome.
Runs down the lateral side of thigh and spirals around to the anterior leg, then to the dorsum of the foot.
Describe the S1/2 dermatome.
Dermatome at the back leg and thigh;
Originates close to the level of the center of gravity
Describe the region of the T10 dermatome.
Dermatome that wraps along the belly button from ventral to dorsal sides of body
What dermatome wraps along the medial side of the foot and over the knee?
L4 Dermatome
The spinal nerve damaged always corresponds to the _______ level of the disc that is herniated. Provide an example.
Lower level:
HNP between C4 and C5 = C5 spinal nerve affected;
HNP between T3 and T4 = T4 spinal nerve affected
What ligament resists extension of the back, such as by stretching backwards with arms overhead and feet planted?
Anterior longitudinal ligament
“Stretch occurs away from where ligament is attached to spine”
What naturally resists flexion at the vertebral column?
The posterior longitudinal ligament and Ligamentum flavum resists flexion of the spine.
What vertebral level does the dural sac and subarachnoid space end?
S2 vertebra level
The patella reflex involves what two dermatome levels?
L3/L4
“Kick the door”
Describe the pathway a needle takes for a lumbar puncture.
Passes spinous processes > interspinous ligament > ligamentum flavum > epidural venous plexus > dura mater > arachnoid mater > subarachnoid
How would a herniated nucleus propulsus between C6 and C7 spinal vertebra present in a patient?
Pain of C7 dermatome and muscle weakness of the distal forearm muscles.
