Flashcards in Back Deck (53)
How many pairs of spinal nerves and how many at each level?
32 pairs; 8C, 12T, 5L, 5S, 1Co
The spinal cord ends at which vertebral level?
L1 or L2
CSF is found where?
In the subarachnoid space
The anterior and posterior segmental
medullary arteries are derived from...(5)
Spinal branches of the ascending cervical, deep cervical, vertebral, posterior intercostal, and lumbar arteries.
Most proximal spinal nerves and roots are accompanied by what arteries?
They do not reach the _____ arteries, but which ones do?
Posterior or anterior spinal arteries. Segmental medullary arteries.
P.504 Moore, plate 168 Netter
White and gray rami communicantes
are found between ______ spinal cord levels, but only _____ are found at the other levels.
What is the "lumbar cistern," what does it contain, and at what vertebral levels does it exist?
An enlargement of the subarachnoid in the dural sac.
Contains CSF and the cauda equina.
Exists from L2 to S2.
At which spinal segments are the cervical enlargement and the lumbosacral enlargement?
At what vertebral level does the spinal cord end?
What is this portion of the spinal cord known as?
L1-L2 vertebral level
Cervical spinal nerves bear the same alphanumeric designation as the vertebra forming the _____ margin of the IV foramina through which it exits the vertebral canal, EXCEPT C-____?
Inferior margin (i.e. the vertebrae below the nerve)
What is the cauda equina and what is the area in which it resides?
It is a loose bundle of nerve roots arising from the lumbosacral enlargement and conus medullaris.
It lies within the the LUMBAR CISTERN of CSF caudal to the termination of the spinal cord.
Where is the most appropriate vertebral location for a lumbar puncture and why?
L4-L5 (sometimes L3-L4), because the spinal cord ends at approximately L1-2, and the dural sac ends at S2. Therefore CSF can be acquired without injuring the spinal cord.
Which is the only vertebral ligament that is in contact with the vertebral foramen?
What parts of the vertebrae does it link together?
Lamina of adjacent vertebrae
A disk herniation is characterized by protrusion of the _____ in which direction?
Nucleus pulposus from the annulus fibrosis POSTEROLATERALLY.
1.) A lumbar puncture is performed by taking a sample of CSF from the _______ (where is this space located?)
2.) At which vertebral level(s) is a lumbar puncture performed? Why?
1.) Lumbar cistern (the subarachnoid space below the spinal cord).
2.) Between vertebrae L4 and L5 or sometimes between L3 and L4. It is done in this region because the spinal cord ends at the level of L1 to L2 and the dural sac ends at the level of S2.
Which parts of a vertebra does the lamina connect?
Transverse process to the spinous process.
What bony feature connects the vertebral body to the transverse process?
The ______ nerve innervates the latissimus dorsi, what is its action?
adduction and medial rotation of the humerus.
Name the three major muscles that adduct AND medially rotate the humerus, along with their innervation.
Lats – thoracodorsal
Teres major – lower subscapular
Pec major – Lateral and medial pectoral nerves
The _______ innervates the serratus anterior, which is responsible for _________.
-long thoracic nerve
-elevation and abduction of the scapula beyond the horizontal level while maintaining its position against the thoracic wall.
How to tell a cervical vertebrae?
C3-7 have transverse foramen for vertebral arteries. Easy to tell C1 (all arch) and C2 (dens). Bifid SPs except C1 and C7 (verterba prominens).
Describe uncinate processes (what/where they are) and what joints they form. What motion do they limit?
Found at the lateral border of the bodies of C3-6 or 7.
Uncovertebral joint (clefts) of Luschka (p.445 Moore): Formed from the uncinate processes (only C3-C6 or C7).
They limit lateral flexion of the cervical spine.
How to tell a thoracic vertebra?
Heart shaped vertebral body, costal facets.
How to tell a lumbar vertebra?
Triangular vertebral foramen, mammillary processes; which are posterior protuberances from the medial aspect of the TPs (where the pedicle meets the TP).
Describe how the ribs articulate with the thoracic vertebrae (T1-10).
The superior costal facet articulates the head of the corresponding rib.
The inferior costal facet articulates with the head of the rib below.
The TRANSVERSE costal facet articulates with the TUBERCLE of the corresponding rib.
At what VERTEBRAL levels are the lumbar and sacral SPINAL segments found?
Where should one perform a spinal tap (give two possible locations)
1. Inserted into the subarachnoid space between L3-4 or L4-L5 (between SPs). POPS THROUGH LIGAMENTUM FLAVUM. (Arachnoid and dura end S2-S3)
What external landmark would help you reliably find the correct vertebral level to administer a lumbar puncture?
Iliac crest to locate L4 – because you want to go between L4-L5.
Where would you administer caudal epidural anesthesia and why?
How would you locate it externally?
In the epidural space caudal to the dural sac (which ends at S2). The anesthesia bathes the S2–S4 spinal nerve roots, including the pain fibers from the uterine cervix and superior vagina, and the afferent fibers from the pudendal nerve.
Because the sacral hiatus is located between the sacral cornua and inferior to the S4 spinous process or median sacral crest, these palpable bony landmarks are important for locating the hiatus. The anesthetic solution spreads superiorly and extradurally, where it acts on the S2–Co1 spinal nerves of the cauda equina.
At approximately what vertebral level does the spinal cord end?
What nerve roots comprise the cauda equina?
Wiki (but look at picture on p.497
What are the extrinsic back muscles (7)?
The trapezius, latissimus dorsi, levator
scapulae, rhomboid major and minor, and the serratus posterior superior and inferior muscles are extrinsic muscles.
At which vertebral level is the spine of the scapula?
Which muscles attach to the superior nuchal line?
Occipitalis, scm, splenius capitis, trapezius
Which muscles attach at inferior nuchal line?
Rectus capitis posterior major&and minor, obliquus capitus superior
What in the filum terminalae
An extension of pia mater
A tumor in the IV space between L5-S1 will affect which nerve root?
Muscles in the suboccipital region are innervated by the _____ ramus of _____, aka the _____ nerve.
Dorsal ramus of C1, aka the suboccipital nerve.
There are _____ IV discs in total. What vertebrae lack IV discs?
23 IV discs total. There are none between C1-C2, and the last is between L5-S1.
How to distinguish cervical vertebrae?
Transverse foramina (though artery does not pass through C7).
How to distinguish thoracic vertebrae?
Heart-shaped vertebral body (Thoracic = heart)
How to distinguish lumbar vertebrae?
Triangular vertebral foramina, mammillary processes.
The ____ space contains the internal vertebral venous plexus and epidural fat.
Give the borders of the triangle of auscultation (superior, medial, lateral).
Superiorly and medially: Inferior portion of TRAPEZIUS.
Inferiorly: Latissimus Dorsi.
Laterally: Medial border of scapula.
What vertebral level corresponds with the PSIS?
S2 spinous process.
Describe where each of the erector spinae attach on the vertebral column
-Iliocostalis: Cervical TPs only (makes sense because it is the most lateral muscle).
-Longissimus: TPs in thoracic and cervical region (and to mastoid process).
-Spinalis: SPs in the upper thoracic and midcervical region (also to the skull).
What movements are permitted at the AC joint? What type of joint is it? What are the articulations? What causes the movement(s)?
Plane joint. Acromion rotates on the acromial head of the clavicle. Occurs during protraction and retraction of the scapula, though NO MUSCLES ACT DIRECTLY ON THE AC JOINT.
Give origin, insertion, action, innervation, and blood supply for trapezius.
Origin: Medial third of nucchal line, nucchal ligament, C7-T12, External occipital protuberance.
Insertion: Lateral third of clavicle, acromion, spine of scapula.
Innervation: Spinal Accessory (CN XI)
Blood: Transverse cervical
-Descending (superior) fibers elevate the scapula (e.g., when squaring the shoulders).
-Middle fibers retract the scapula (i.e., pull it posteriorly).
-Ascending (inferior) fibers depress the scapula and lower
-Descending and ascending trapezius fibers act together in rotating the scapula on the thoracic wall in different directions, twisting it like a wing nut.
-The trapezius also braces the shoulders by pulling the scapulae posteriorly and superiorly, fixing them in position on the thoracic wall with tonic contraction; consequently, weakness of the trapezius causes drooping of the shoulders.
Sympathetic fibers innervate...(4 general things)
Smooth muscle, modified cardiac muscle, glands, medulla of adrenal gland.
What gives blood supply to the dorsal and ventral nerve roots?
Anterior and posterior radicular arteries
From which artery does the great artery of Adamkiewicz arise?
Left posterior intercostal, from aorta
Which arteries reinforce blood supply to the cervical and lumbar enlargements?