Lecture 2 Spinal nerve and back musculature Flashcards
Central canal contains what to suspend and protect the spinal cord
Cerebrospinal fluid
What do the filum terminale externum/internum do
Fix the spinal cord to coccyx
Three types of spaces formed by the meninges
Epidural - between dura and vertebral bony wall
Subdural (POTENTIAL SPACE) - between dura and arachnoid
Subarachnoid- cerebrospinal fluid
Ligamenta flava = ?
Facet joint hypertrophy = ?
Flava = spinal stenosis
FJ hypertrophy = nerve root impingement
Central vs paracentral disc herniation =
Central = spinal stenosis (flava)
Paracentral = nerve root impingement (Facet joint hypertrophy)
Explain a disc protrusion
A little worse than a buldge; can be indicated for extension exercises and traction; annulus fibrosis is still partially functional
Explain a disc sequestrian
Buldge->protrusion->extrusion-> sequestrian is the worst. not indicated for any extension exercise or traction, as the annulus fibrosis is completely gone
What forms the denticulate ligament and what does that ligament do
Pia mater forms the denticulate ligament and this ligament attaches the pia mater to the spinal cord
What are dorsal root ganglia
Cell bodies of sensory neurons
Explain the dorsal root and afferent or efferent
Dorsal root (Afferent) = CNS + PNS processes of the sensory neuron axons
Explain the ventral root and afferent or efferent
Ventral root (efferent) = rootlets from somatic motor neuron and preganglionic axons
How short is the spinal nerve
Very short
How many functional components do all spinal nerves contain; what are those components?
4 components= Somatic sensory, somatic motor, visceral sensory, and visceral motor
Which nerve contains only somatic motor component?
C1
Visceral motor is a…
2 cell system with 2 subdivisions but ONLY sympathetic motor in spinal nerves to somatic wall
Sympathetic preganglionic axons …
white ramus communicans and are myelinated (faster)
Sympathetic ganglion…
synapse with soma of 2nd ganglionic neuron
Postganglionic axons
gray ramus communicans and are slower because they are nonmyelinated
Explain the 4 pathways of Preganglionic sympathetic axon
1) synapse in ganglion with 2nd ganglionic neuron (paravertebral ganglia)
- postganglionic axons of 2nd neuron - gray ramus to spinal nerve (slow)
2) Ascending to form sympathetic trunk (myelinated)
3) Descending to form sympathetic trunk (myelinated)
4) Splanchnic nerve (myelinated) directly to abdominal/pelvic cavities
What does the lumbar and thoracic splanchnic nerve innervate
abdominal organs
Greater, lesser and least splanchnic nerve levels
Greater = T5-T9
Lesser = T10-T11
Least = T12
What does the sacral splanchnic nerve innervate
Pelvic organs
Parasympathetic preganglionic axons use (blank) splanchnic nerve
Pelvic splanchnic nerve
Parasympathetic preganglionic axons are (blank) to target structure while sympathetic pregang axons are (blank) to target structure
close by; far away
Parasympathtic is only in
visceral organs
Sympathetic activates
sweat glands and arrector pili, and constricts vessels
Radial frequency ablation =
Burning medial branch of dorsal ramus to manage chronic pain
Ventral ramus trunk spinal nerve =
intercostal nerve
Typical trunk spinal nerve in Muscular/collateral branch =
serratus posterior, intercostals, abdominal wall muscles
Where does the spinal cord end
Ends at T12-L2 but still divides into 5 regions although they dont match up with the vertebral regions
How many pairs of spinal nerves, and which region has 1 more than usual?
31 pairs, cervical has 1 more (8) b/c of the one above atlas
Spinal nerve impingement formula =
D+1=P
T or F: Extrinsic muscles have different branches following peripheral nerves
T
Cutaneous innervation of C2 through greater occipital nerves pierces …
Semispinalis
What forms plexus for back/gluteal regions
Ventral rami
Serratus posterior innervation=
Intercostal nerve of ventral rami
Erector spinae innervation=
dorsal rami of spinal nerves
Which specific erector spinae muscles depress the rib cage for expiration?
Iliocostalis lumborum+thoracis and Longissimus thoracis
Where does the spinalis thoracis most proximally attach?
Spinous process of L2
Function of erector spinae
Back ext (and neck); unilaterally SB/RT
Only muscle in laminar groove below L2; also then core of the back
Multifidi
Distal attachment of Multifidi ends at
Spinous process of C2
Semispinalis starts at (blank) and the thoracis subdivision proximally attaches at …
thoracic region; transverse processes of T10-T6
Semispinalis capitis is innervated by
Dorsal rami of spinal nerves
Semispinalis fucntion
back ext, ipsilateral SB, contralateral rotation
Cervicis/capitits = neck ext, SB, contra RT
T or F: Obliquus capitis inferior produces head movement
No head movement because it is not attached to the head
Where do headaches commonly originate
Greater occipital neuralgia; cervicogenic headache
