Spinal cord Anatomy Flashcards
Which spinal nerves come out above/below their respective vertebrae?
Which vertebrae has 2 spinal nerves associated with it?
C1-7 come out above
C8-S5 come out below
- C7
Where is the cervical enlargement?
C5-T1 (cervical plexus- -upper limbs)
Where is the lumbar enlargement?
L1-S2 (lumbosacral plexus–lower limbs)
Where does the sc extend to in children?
L3
Which of the 2 layers of cranial dura is the spina dura continuous with?
Inner meningeal dura
Denticulate ligaments are an extension of which layer?
Pia, anchoring the sc to the dura
For the most part sympathetics have short preganglionics and long postganglionics. What are the exceptions (root contribution and where they synapse)?
- Greater splanchnic n, T5-T9, celiac ganglion
- Lesser splanchnic n, T10-T11, superior mesenteric and aortico-renal ganglia
- Least splanchnic n, T12, renal plexus
Pia mater (as the filum terminale) fuses w/dura mater to form the ____________________.
Coccygeal ligament
SAS caudal to the conus medullares is known as the ______________________.
Lumbar cystern
What is the general shape of the anterior and posterior spinal aa?
1 anterior: straight
2 posterior: wiggly
What sensory area would a dorsal root form?
Dermatome
What dermatome innervates the back of the head?
C2
What dermatome innervates the thumb and some index finger?
C6
What dermatome innervates the nipple line?
T4
What dermatome innervates the umbilicus?
T10
What dermatome innervates the knee cap?
L4 (slide says L3)
What dermatome innervates the lateral foot?
S1
During devo, upper limbs rotate ______ and lower limbs rotate ______.
Laterally, medially
What grooves run on the dorsal side of the sc, medial to lateral?
- Posterior median sulcus
- Posterior intermedial sulcus
- Posterior lateral sulcus
What grooves run on the ventral side of the sc, medial to lateral?
- Anterior median fissure
- Anterior lateral sulcus
What is the name of the fibers that cross w/in the anterior median fissure?
Anterior commissure
Where does the dorsal root enter the sc, bringing in sensory info?
Posterior lateral sulcus
What nuclei do the posterior intermediate sulci separate?
Nucleus gracilus and cuneatus
Where does the ventral root exit the sc, bringing out motor info?
Anterior lateral sulcus
What are the names of the 3 large regions of white matter in the sc, dorsal to ventral?
- Dorsal funiculus
- Lateral funiculus
- Ventral funiculus
What is the name for a subregion of a funiculus?
Fasciculus
What are the names of the 3 large regions of gray matter in the sc, dorsal to ventral?
- Posterior horn (PH)
- Intermediate gray (IG)
- Anterior horn (AH)
What nucleus lives in the bump sticking out of the IG?
Intermediolateral nucleus (IML)
Motor to glands, bv’s, viscera (autonomics, parasymp) are examples of which 3-letter functional group?
GVE
Pain, temp, touch, etc. from skin and body wall are examples of which 3-letter functional group?
GSA
Taste and smell are examples of which 3-letter functional group?
SVA
Motor to skeletal mm. is an example of which 3-letter functional group?
GSE
Pain and stretch from viscera are examples of which 3-letter functional group?
GVA
Mm. of gill origin (pharynx, larynx, mastication, and facial expression; CN’s 5, 7, 9, 10, 11) are examples of which 3-letter functional group?
SVE
From dorsal to ventral, explain the different 3-letter functional groups found in the sc.
- GSA, GVA in PH
- GVE in IG
- GSE in AH
What is the general function of the substantia gelitanosa, and what nucleus are they associated with?
In what region of the gray mater are they found?
Modify sensory input by synapsing on dendrites in the nucleus proprius (sc can filter out some painful info).
- Distal posterior horn
What’s another name for the nucleus proprius? Is it mainly sensory, motor, or both?
What spinal nerve levels is it found in?
In what region of the gray mater are they found?
- Proper sensory nucleus
- Receives many sensory inputs
- Found in all cord levels
- Posterior horn
What’s another name for the nucleus dorsalis? Is it mainly sensory, motor, or both?
What spinal nerve levels is it found in?
In what region of the gray mater are they found?
- Clark’s nucleus
- Receives muscle spindle information (sensory)
- C8-L3
- Intermediate gray
What specific types of neurons are in the IML (intermediolateral nucleus)?
What spinal nerve levels is it found in?
In what region of the gray mater are they found?
- *Preganglionic cholinergic sympathetic efferents (GVE)
- T1-L3
- Intermediate gray
What specific types of neurons are found in the medial and lateral motor nuclei?
In what region of the gray mater are they found?
- Alpha motor neurons
- Anterior horn
Where is the phrenic nucleus found?
@ cervical ventral horn, C3-4-5 medially
Where is the spinal acecssory nucleus found?
@ cervical ventral horn, C1-C6 laterally
What do muscle spindles detect?
What do golgi tendons detect?
- Muscle length
- Muscle tension
What is the name of the part of the muscle spindle to which sensory neurons attach?
Nuclear bag
What types of neurons feedback to the nuclear bag to reset it after it has been stretched?
What are the names of the neurons coming into and out of the nuclear bag?
- Gamma neurons
- Ia and alpha neurons
What are the 3 types of non-encapsulated receptors?
(pain/temp + touch)
- Free nerve endings
- Merkel’s disks
- Hair follicles
What are the 3 types of fast adapting receptors (less important)?
(hair + corpuscles)
- Hair follicles
- Meissner’s corpuscles
- Pacinian corpuscles
What’s the function and distribution of free nerve endings?
- Pain/temp
- Deep skin, viscera
What’s the function and distribution of Merkel’s disk?
- Touch
- Feet, hands, genitals, lips
What’s the function and distribution of hair follicles?
- Touch
- Where ever there’s hair
What’s the function and distribution of Meissner’s corpuscles?
- 2 pt discrimination
- Fingertips, hairless skin, joints, ligaments
What’s the function and distribution of Pacinian corpuscles?
- Vibration
- Fingers, toes, palms, mesenteries, peritoneum
What’s the function and distribution of Ruffini endings?
- Stretch, pressure
- Dermis
What’s the function and distribution of joint receptors?
- Joint position
- Joint capsules, ligaments
What’s the function and distribution of neuromuscular spindles?
- Limb muscle stretch/length
- Muscles
What’s the function and distribution of Golgi tendon organs?
- Muscle tension
- Muscle-tendon junction
For dorsal root afferents, how myelinated is the lateral division?
What types of sensations run thru there?
- Light myelin
- Pain/temp, light touch, visceral afferents
For dorsal root afferents, how myelinated is the medial division?
What types of sensations run thru there?
Where does it send its collaterals?
- Mucho myelin
- 2 pt discrimination, limb position, muscle stretch
- Medulla
What 2 receptors would you find in most ligaments?
- Meissner’s corpuscles (2 pt discrim)
- Joint receptors (joint position)
Which receptors would you find in the hand, superficial and/or deep?
Theoretically, every one that we learned
