Axial Exam Flashcards
Vertebral foramen v intervertebral foramen- walls
Vertebral foramen- spinal cord, bordered by body, pedicles, lamina
IV foramen- spinal nerve exits between 2 vertebrae
Special features of C3-C7 vertebrae (4)
- small body
- uncinate process on top, uncovertebral joints
- C3-C6 bifid SP’s
- Transverse foramen- vertebral artery (C1-C6)
Special features of Atlas (C1)
No body, hole for dens instead
Posterior tubercle instead of SP
Articulates w occipital condyles
Distinguishing features of T1-T12
- Taller broader bodies
- Long SP’s angled inferior
- TP’s angled posterior
- Costal facets (3 each, superior and inferior on body, on TP except T11/12)
Features of L1-L5 vertebrae
- largest bodies
- thick SP’s point straight posterior
How many articulations on a typical vertebrae? Typical thoracic vertebrae
- 6 (2 body, 2 sup & inf facets)
- 12 on T1-10 (6 normal, 3 costal facets each side)
Intervertebral Discs - type, make up how much of the spine?
FC joint (symphyses)
Absorb shock, no disc between C1-C2
20-33% total height
(Cervical discs 3 mm, lumbar 9 mm thick)
Parts of IV Disc (3)
- Nucleus pulposus- 80-85% water, gelatinous
- Annulus fibrosus outer layer - lamellae - concentric sheets, tensile strength, oriented 120º opposite from each other
- AF Inner layer - attach to hyaline cartilage vertebral endplates
- both type 1 collagen fibers
Zygoapophyseal joint type
AKA facet joints
4 per vertebra (2 superior, 2 inf articular processes and facets)
- synovial joint, capsule looser in c-spine
Cervical facet angle
45% angle, lower posteriorly
- allows flex/ext, rotation, and sidebend
Thoracic facet angle
nearly vertical (80º), angled 20º inward - allows rotation, sidebend, limits FL/Ext
Lumbar facet angle
90º vertical, angled 45º inward
- allows FL/Ext, limits sidebend and especially rotation
Anterior Longitudinal Ligament
- Sacrum-C1, limits extension
- Deep fibers- Discs- reinforce annulus fibrosus
- superficial fibers attach to bodies not discs
Posterior Longitudinal Ligament
- Sacrum-C2, limits flexion
- Attaches to bodies & discs
Ligamentum Flavum
- Intersegmental between laminas
- Sacrum-C1, limits flexion
- Dense fibrous elastic CT
- Constant tension, reinforce spinal cord
Transverse and spinous ligaments (3)
- Interspinous (SPs)
- Supraspinous (outside, post to SP’s, L5-T1)
- Intertransverse (TP’s)
- All limit flexion
Broadenings of anterior longitudinal ligament
- anterior atlanto-occipital membrane
- anterior atlanto-axial membrane
Tectorial membrane
Posterior Longitudinal Ligament renamed from C2 to occiput
Continuation of ligamentum flavum
- Not elastic fibers
- posterior atlantoocipital membrane
- posterior atlantoaxial membrane
Ligamentum nuchae
- Broadening of supraspinous ligament, C7 to occiput
- Helps keep spine extended
Cruciform ligament (2 parts)
- Transverse ligament- supports dens, atlas to atlas
- longitudinal fascicles- superior to occiput, inferior to axis
- Prevent ant mvt of C1 on C2
Alar ligaments
- Skips from axis to occiput- from proximal lateral dens outward
- Limits sidebend, frontal plane
Which vertebral ligaments restrict flexion? (5)
- Post Longitudinal Lig (+ tectorial membrane)
- Supraspinous lig (+ ligamentum nuchae)
- Interspinous ligs
- Ligamentum flavum
- Intertransverse ligs, depending on orientation
What restricts spine extension? (2)
- Ant longitudinal ligament (ant atlantoaxial, ant atlantooccipital
- Spinous processes
Thorax cutaneous nerve innervation
- Intercostal nerves from ventral rami- anterior and lateral cutaneous branches
- posterior rami of spinal nerves innervate back
Extrinsic v Intrinsic back muscles
- Extrinsic = attach outside vertebral column (superficial and deep layer)
- Intrinsic = attach inside vertebral column (superficial, intermediate, and deep layers)
Extrinsic superficial back muscles (4)
- Levator scap (C1-4 TP to sup angle scapula)
- Trapezius
- Latissimus dorsi
- Rhomboids
Extrinsic deep back muscles (2)
- Serratus posterior superior (SP lower cervical/upper thoracic TO upper ribs, elevate ribs)
- s.p. inferior (SP lower thoracic/upper lumbar TO lower ribs, depress ribs)
- intercostal N’s
Superficial intrinsic back muscles (2)
- splenius capitis
- splenius cervicis
Muscles that do extension, ipsilateral rotation, and sidebend
- splenius capitis
- splenius cervicis
- erector spinae (iliocostalis, longissimus, spinalis)
Intermediate intrinsic back muscles (3)
Erector spinae
- Iliocostalis (L, T, C)
- Longissimus (T, C, capitis)
- Spinalis (T, C, capitus blends with semispinalis capitis)
Deep intrinsic back muscles (6)
- Transversospinals (semispinalis, multifidus, rotatores)
- interspinalis
- intertransversarii
- quadratus lumborum
Muscles that extend, contralaterally rotate, I/L sidebend
- Transversospinals (semispinalis, multifidus, rotatores)
Suboccipital triangle borders
- rectus capitis posterior major
- obliquus capitis superior
- obliquus capitis inferior
Suboccipital triangle - Important structures (3)
- Vertebral artery runs transversely in triangle
- Suboccipital nerve comes out of triangle, innervates muscles
- greater occipital nerve comes out below triangle, separates semispinalis from spinalis capitis
Joints of sternum- type and number
- manubriosternal (FC joint)
- costochondral (1-10, hyaline synchondroses)
- sternocostal (true ribs 1-7)
- false ribs = 8-10, join to costal cartilage
- floating ribs = 11-12
Costovertebral Joints
synovial, 2 articulations. – Costovertebral- rib w its vertebrae, ribs 2-10 also articulate with superior vertebra
Costovertebral Radiate ligament
Capsular, head of rib to 2 vertebrae & intervertebral disc
Costotransverse Joints
20 (10 each side)
- Costal tubercle of rib to respective transverse costal facet
Costotransverse Ligaments (3)
- Superior - costal neck to superior TP
- Proper- head and neck to tubercle
- Lateral- posterior to tubercle
Development of curves of spine
Newborn spine kyphotic
Transitional phase: cervical lordosis develops first, lumbar later on, becomes stable in puberty
Muscles of respiration (3)
Diaphragm Internal Intercostal (run down and back) External Intercostal (run down and forward)
Diaphragm
O: lower margins ribs 7-12
I: Right and left crura, L1-L3 vertebral bodies, discs, ALL
- has holes for esophagus, aorta, vena cava
Abdominals- orientation of each layer
Ext oblique, Int oblique, Transverse abs
happy on the outside, sad on the inside, stressed in the deepest layer
Abdominal aponeuroses- orientation above and below arcuate line-
- arcuate line- 5 cm below umbilicus
- ABOVE: ext obl on top, int obl splits around rectus ab, transverse ab on bottom.
- BELOW: all 3 aponeuroses run above rectus
Posterior Triangle boundaries
- Ant: sternocleidomastoid
- Post: trapezius
- Inf: clavicle
Posterior Triangle contents (9)
- Scalenes (anterior, middle, posterior)
- Levator scapulae
- Splenius capitus
- External jugular vein enters neck
- CN XI accessory N- out jugular foramen to trap and SCM
- Subclavian artery
- Brachial plexus
Muscles that flex, contralaterally rotate, ipsilaterally sidebend (3)
- Sternocleidomastoid (flexes lower c-spine)
- Anterior scalene (middle and post only do c/l rot and sidebend)
- External oblique
Interscalene triangle- borders and contents (2)
- Between anterior and middle scalenes and first rib
- Contains: subclavian artery, brachial plexus nerve roots
Thoracic outlet syndrome- possible causes
Brachial plexus compression, neurovascular symptoms
- Could be scalenes, clavicle, pec minor, subclavius
Anterior triangle boundaries
Ant- midline neck
Post- sternocleidomastoid
Sup- lower border mandible
Contents of anterior triangle (muscle/bone)
- Hyoid bone
- Suprahyoid and infrahyoid muscles (sternohyoid, sternothyroid, thyrohyoid, omohyoid)
Function of suprahyoid and infrahyoid muscles
- Suprahyoid: form floor of mouth, secondary muscles of mastication
- Infrahyoid- swallowing and moving larynx
Ansa cervicalis
Cervical plexus- makes a loop, innervates supra and infra hyoid muscles
- C1-C3??
Neurovascular contents of anterior triangle (8)
- Sympathetic chain, hypoglossal N, glossopharyngeal N, phrenic N
In carotid sheath: - Common carotid, splits to internal and external
- Internal Jugular vein
- Vagus nerve CN X
Path of internal and external carotid arteries
- Internal carotid: to brain without branching in neck, enters through twisty carotid canal
- External carotid: supplies neck and face, many branches.
Middle meningeal artery path
- branch off external carotid, supplies interior calavera
- Enters through foramen spinosum, runs between dura and skull
- Epidural hematoma- TBI, bleeding presses on brain
Internal jugular vein- path
- Drains head face and neck
- From sinuses (spaces between dura in skull) through jugular foramen, IJV, to brachiocephalic vein
Sympathetic chain
Carries sympathetic fibers up to head
Phrenic nerve
C3-4-5 keeping you alive
- Innervates diaphragm, runs on top of anterior scalene
Vagus Nerve - CN X
- To larynx and parasympathetic innervation to thorax and gut
- Out jugular foramen, runs in carotid sheath w common carotid A and int jugular V)
Hypoglossal nerve (CN XII)
To muscles of tongue, exits through hypoglossal canal
Glossopharyngeal N (CN IX)
- taste and sensation to post 1/3 tongue
- motor to pharynx (with CN X)
- exits through jugular foramen
Visceral structures of anterior triangle, 3 layers, 2 structures each
Anterior endocrine layer- thyroid and parathyroid
Middle respiratory layer- trachea and larynx
Posterior alimentary layer- pharynx and esophagus
Parts of larynx (6 cartilages)
- Thyroid- shields vocal apparatus
- Cricoid- complete ring inferior to thyroid cartilage
- Epiglottis- flap attached to post surface thyroid cartilage
- 3 smaller cartilages- vocal folds and phonation
Facial nerve CN VII path
- enters skull through internal acoustic meatus (with CN VIII)
- exits skull through stylomastoid foramen, runs under parotid gland
- TO muscles of facial expression, taste anterior 2/3 of tongue, parasympathetic innervation
Trigeminal nerve CN V- 3 divisions
Sensory to face
- V1 Opthalmic- out superior orbital fissure, forehead to tip of nose
- V2 Maxillary- out foramen rotundum, to top lip
- V3 Mandibular- out foramen ovale, to chin
Temporomandibular joint movements
- FIrst 15º, Head of mandible rotates in mandibular fossa of temporal bone
- > 15º, glides forward onto Anterior tubercle- convex surface ant. to mandibular fossa
- Articular disc- FC, attaches to lateral pterygoid tendon anteriorly, protrudes head of mandible
Lateral temporomandibular ligament
Supports TMJ (along with capsule, FC disc, and bony configuration)
Olfactory CN I
- sense of smell
- sits on ethmoid bone above nasal cavity
Optic CN II
- sense of vision
- through optic canal
CN III (oculomotor) CN IV (trochlear) CN VI (abducent)
to extraocular muscles
through superior orbital fissure (CN 3,4,6 together)
Vestibulocochlear CN VIII
- through internal acoustic meatus to inner ear
- balance and hearing
Accessory CN XI
out jugular foramen
to SCM and trapezius
Sympathetic v Parasympathetic Chains- difference between neurons
Sympathetic: 1st neuron short, 2nd neuron long
- Parasympathetic: 1st neuron long, 2nd neuron short
Sympathetic chain- path of neurons
- 1st neuron- down spinal cord, exits with spinal nerve, synapses on sympatic chain ganglion next to T/L spine
- 2nd neuron- straight to organ
Parasympathetic chain- path of neurons
- 1st neuron: cell body in brainstem, vagus N to synapse in target organ
- 2nd neuron: acts on target organ
3 layers of pelvic floor muscles (deep to superficial)
- Pelvic diaphragm (levator ani)
- External urethral sphincter
- Urogenital diaphragm- perineum muscles
3 parts of the levator ani
- Puborectalis (loop from pubic symphysis)
- Pubococcygeus
- Iliococcygeus
(obturator internis runs on top of the tendinous arch of levator ani))
Inferior aperture (borders of pelvic floor)
- inf pubic symphysis
- inf pubic rami
- ischial tuberosities
- sacrotuberous and sacrospinous ligaments
- Sacrum and coccyx
2 differences in function in male pelvic floor muscles
- bulbospongiosus surrounds urethra- assists w erection, ejaculation, pushes out residual urine
- Ischiocavernosus- guidewires for penis rigidity, ejaculation
Type of fiber distribution in pelvic floor muscles
- 70% slow twitch, 30% fast twitch
- always active in standing, need endurance
- need power to hold in pee
Innervation of pelvic floor muscles
- Pudendal nerve (S2-3-4 keeps pee and poop off the floor!)
- Contracting inhibits parasympathetic urge to pee
Alcock’s Canal
- path of Pudendal N, potential entrapment
- between sacrospinous and sacrotuberous ligaments, runs on top of piriformis, coccygeus, and obturator internis,
Autonomic nerve input the bladder
- Sympathetic promotes storage - T11-L2. detrusor relaxes, internal sphincter contracts
- Parasympathetic promotes bladder emptying - S2-S4, detrusor contracts, internal sphincter relaxes
Causes of pelvic floor dysfunction
- Childbirth, chronic UTI’s, age related soft tissue changes
- Pelvic/abdominal surgery cuts stabilizing muscles
- Pain inhibition- LBP, pelvic pain
Neurological causes of pelvic floor dysfunction
- denervation due to: spinal cord injury or severe herniated disc
- diabetes, autonomic neuropathy
- CNS reduced cognitive awareness- CVA, MS, Parkinson’s
Insertions on mastoid process (3)
splenius capitis, SCM (+ sup nuchal line)
longissimus capitis
Insertions on superior and inferior nuchal lines (2 each)
Superior: splenius capitis, sternocleidomastoid
Inferior: rectus capitis posterior major and minor
