PT 706 Exam #3

Spinal Cord

-The vertebral column is longer than the spinal cord because in embryonic development the vertebral column grows at a rapid rate -Continuous with Medulla Oblongata of brainstem -Runs through opening in the occiput = Foramen Magnum -Ends at L2 vertebral level (L1-L3)

Superficial Extrinsic Back Muscles

-Traps: cervical extension, contralateral rotation, ipsilateral SB -Levator Scapulae: cervical ipsilateral rotation and Sb -Rhomboids and Latts: upper limb movement

Intrinsic Group of Back Muscles

-True back muscles -Considered the deep muscles of the back -Initiate and control movement of the vertebral column; maintain erect posture -3 Layers: --Superficial Layer: one posterior neck muscle group - splenius capitis and cervicis -Intermediate Layer: largest muscles of the back - Erector spinae group - 3 muscles --Deep Layer: ---Transversospinalis group: 3 muscles ---Segmental group (deepest layer) - 3 muscles -All intrinsic back muscles are innervated by posterior primary rami of spinal nerves

Parasympathetic System Distribution and Functions

-"Craniosacral Outflow" -Maintenance functions -Distributed to head neck, and body cavities, NOT body wall or LIMBS except penis and clitoris (Acetylcholine) -Slows HR, constricts pupils, aids in rectal and bladder emptying

Sympathetic Distribution and Functions

-"Thoracolumbar Outflow" -Emergency functions (fight or flight) innervates glands, smooth muscle in body wall, blood vessels and sweat glands in limbs, and arector pili muscles in skin (norepinephrine) -Increases HR, dilates pupils, maintains urinary continence, vasoconstriction of blood vessels except for coronaries

Each Spinal Cord Segments Has:

-Ventral Horn: contains motor cell bodies that have axons ending in muscle -Dorsal Horn: contains sensory fibers that have nerve cell bodies outside of the CNS in dorsal root ganglion (DRG) -In addition, T1-L2 has Lateral Horns: "intermediate zone", contains cell bodies for sympathetic portion of ANS

Parasympathetic ANS

-2 Neuron System: Long pre-gangionic and SHORT post0ganglionic neurons -Pre-ganglionic Fibers arise from nuclei in brain associated with 4 cranial nerves (III, VII, IX, and X) and Sacral spinal cord segments 2-4 -Ganglia are located within or close to the organ innervated and are very small (therefore no parasympathetic chain exists)

Comparing Location of the Spinal Cord Segments to Vertebral Body Segments

-If you know the vertebral column BONY segment, ADD to final the SPINAL CORD SEGMENT (NOT THE SPINAL NERVE) -Cervical Body: Add 1 for cord level -Upper Thoracic Body: add 2 for cord level -Lower thoracic Body: Add 3 for cord level -Upper Lumbar Body: Add 3 or more for cord level

Ligament Stabilization of L5-S1 Junction

-Iliolumbar Ligament: --Attaches L5 transverse process to iliac crest and anterolateral sacrum --Stabilizes lumbosacral junction (L1-S5) --Rarely has a superior band attaching to L4 -Anterior Longitudinal Ligament: --Crosses anterior L5-S1 Junciton

Dermatomes

-Is an area of the skin supplied by the sensory (Dorsal) root of a single spinal nerve -Peripheral N pattern vs Dermatome Pattern: --Each peripheral nerve comes from more than 1 spinal cord segment and is a mix of ventral rami ---There are branchings of peripheral N that are not confined to a dermatome boundary ---Sensory Fibers from periphery enter more than 1 spinal segment ---No anesthesia occurs unless 2 or more consecutive dorsal roots have lost their function

Submental Triangle Contents

-Lymph nodes

Function of Intervertebral Joints

-Main WB joint of vertebral column -Distribute and disperse WB loads

Spinal Cord Membranes

-Meninges (coverings): --Dura Mater (D): outermost layer, "tough mother", extends over spinal nerves --Arachnoid Mater (A):Middle layer, thin, filmy --Pia Mater (P): innermost layer, "tender mother" -Outside the dura mater there is a bunch of fat and blood vessels that protect and cover the spinal cord

Anterior Neck Triangle

-Midline -Anterior border SCM -Mandible to mastoid

Muscular Triangle Borders

-Midline -Superior Omohyoid -Anterior SCM

Deep Neck "Prevertebral"

-Muscles that flex the head and neck at the AO joints and cervical joints: --Longus Colli (C1 anterior tubercle TO bodies of upper C and T processes to T3) ---Flexes C spine ---Ipsilateral rotation --Longus Capitis (T processes C3-C6 TO base of skull) ---Flexes C spine -Ventral Primary Rami C2-C6 for colli and C2, C3 capitis

Extrinsic Group of Back Muscles

-Not true back muscles -2 layers -Superficial: 4 muscles that initiate and control upper limb movement (traps, levator scapulae, rhomboids, latts) -Intermediate: 2 muscles that initiate and control respiratory movement; proprioceptive input (serrates posterior superior and inferior) -All of these muscles are innervated by nerves from ventral primary rami (traps - spinal accessory nerve)

Sympathetic Pre-Ganglionic Fibers

-Once in the sympathetic trunk, there are several possibilities for the pre-ganglionic fibers to course: 1. Pre-ganglionic fiber may synapse with a post-ganglionic fiber in the sympathetic ganglion at the same level 2. Pre-Ganglionic fiber may ascend or descend the trunk to synapse with a post-ganglionic fiber at a different level 3. Pre-ganglionic fiber may not synapse in trunk but may travel to abdomen through Splanchnic Nerves (greater, lesser, and least) and synapse in ganglia around the aorta. (prevertebral ganglia or given specific names like Celiac plexus, Solar Plexus, or superior and inferior mesenteric ganglia)

Named Parasympathetic Fibers

-Only the pre-ganglionic parasympathetic neurons have names - they are the Pelvic Splanchnics -Caveat: Don't confuse these with Sympathetic Splanchnics

Hyoid Bone

-Palpable superior to thyroid cartilage -No bony articulations of the head and neck -Muscle and soft tissue attachments -Important interface being attached to the oral cavity superiorly, the larynx inferiorly, and the pharynx posteriorly through muscles, membranes, and ligaments

Carotid Triangle Borders

-Posterior Belly Digastric -Anterior border SCM -Superior Belly Omohyoid

Deep Neck "Prevertebral Region"

-Rectus Capitis Anterior (deep to longus capitis) C1 to occiput --Flexes AO -Rectus Capitus Lateralis --C1 to occiput --Laterally flexes AO/Stbilizer -Ventral Primary Rami C1, C2

Plexus Distribution

-Remember that once a plexus forms, a nerve is a mix of several spinal nerves thereafter! -Cervical Plexus (C1-C4) -Brachial Plexus (C5-T1) -Lumbosacral Plexus (L2-S3)

Parasympathetic Sacral Fibers

-Sacral Pre-Ganglionic Fibers exit the spinal cord at their corresponding levels with their spinal nerves, but leave these nerves immediately to remain within the pelvis (i.e. no parasympathetic innervation of body wall except for penis and clitoris) -Synapses with post-ganglionic fibers occur within the pelvis -Post-ganglionics then innervate pelvic organs and the terminal digestive system

Myotomes

-Segmental innervation by the ventral root of a single spinal nerve -Most skeletal muscles are innervated by 2 or more spinal cord segments because of plexuses -A single peripheral nerve represents several myotomes -Muscles sharing common actions are usually innervated by the same myotomes -The more distal the joint, the more caudal the spinal cord segment -Muscles are not usually innervated by exact spinal cord segment as the skin overlying the muscle -All muscles that extend the elbow have the C7 myotome -Elbow flexors have the C5 myotome

Blood Supply and Venous Drainage of Spinal Cord

-Semental/Spinal AA: travel through IVF (branches of vertebral aa, aorta or. external iliac aa) -Spinal Cord: Anterior Spinal A (2/3 cord at any given level) and 2 posterior spinal arteries (1/3 cord at any given level) -Veins: 2 plexuses along entire length of cord and column -External Venous Plexus: external to canal, both anterior and posterior -Internal Venous Plexus: internal canal -Intervertebral Veins (IVF) -No valves, quick spread of infection, cancer

General Visceral Afferent (GVA)

-Sensation from mucous membranes, glands, blood vessels - (poor localized pain, also associated with autonomic reflexes - motility, nausea, vomiting)

General Somatic Afferrents (GSA)

-Sensory -Transmit sensation from body to spinal cord (pain, temperature, touch, pressure, proprioception)

Intermediate Extrinsic Back Muscles

-Serratus Posterior Superior: Elevates ribs 2-4 -Serratus Posterior Inferior: Depresses ribs 9-12 -Superficial Respiratory muscles; part of the thoracic wall -Innervated by thoracic ventral primary rami (intercostal nerves)

Lymphatics of Spinal Cord and Vertebral Column

-Spinal Cord: None -Column: scant, empty into lumbar lymphatic chains and thoracic duct

Cervical Spinal Nerves

-Spinal nerves exit ABOVE corresponding vertebra --C1 spinal nn: exit between occiput and C1 --C2 spinal nerves: exit through IVF between C1 and C2 --C3 spinal nerves: exit through IVF between C2 and C3 --C8 spinal nerves: exit through IVF between C7 and T1

Infrahyoid "Strap" Muscles

-Sternohyoid: depresses hyoid after it has been elevated with swallowing, stabilizes it -Omohyoid: depresses and retracts hyoid, stabilizes it -Sternothyroid: depresses hyoid and larynx -Thyrohyoid: depresses hyoid and elevates larynx -Innervation: Ansa Cervicalis

Submandibular Triangle Contents

-Submandibular gland, nodes -Hypoglossal N (CN XII) Mylohyoid (CN V-3) -Branches of the facial N (CN VII) -Branches of Facial A

4 Subtriangles in the Anterior Triangle

-Submetnal Triangle -Submandibular Triangle -Muscular Triangle -Carotid Triangle

ANS

-Sympathetic: originates in Thoracic region (T1-L2) of spinal cord, and is distributed everywhere there is a vasculature ("Fight or flight") -Parasympathetic: originates in Brian (cranial nuclei) and Sacral region of spinal cord, and is distributed in head neck, and body organs, as well as ONE portion of body wall (penis and clitoris) ("maintenance")

Ligaments of the Median A/A Joint

1 . Strong ligaments hold dens to anterior arch of C1 2. 2 Joint cavities - 1) dens - anterior arch of C1 and 2) dens transverse ligament of the atlas 3. Alar ligaments (2) attach dens to foramen magnum. Limits side bending and rotation of head and neck

Muscles Bilateral Action Producing Thoracic and Lumbar Extension

1 .Erector Spinae 2. Mutifidus 3. Semispinalis Thoracis 4. Interspinalis

Annulus Fibrosis

1. 10-20 concentric rings of fibrocartilaginous lamellae 2. Directed obliquely at right angles to each other 3. Restricts distraction, shear, and torsion forces 4. Provides strong bond between vertebrae

Periosteum, Bones, Ligaments, Joints, and Capsules are Supplied By

1. 2 Segmental Aa from the Aorta which give off: -Periosteal and Equatorial branches -2 spinal branches and 2 anterior and posterior vertebral canal branches -2 Anterior and posterior segmental branches

A/A Joint

1. 3 Artuclations -2 lateral A/A joints - between C1 lateral masses and C2 superior facets. Gliding synovial joints -1 Median A/A joint 2. Rotation is largest motion (45-50 deg.); little flexion or extension 3. Cranium and C1 rotate together on C2

Innervation of Vertebral Column

1. Facet Joints: innervated by medial articular branches of posterior primary rami from 2 adjacent segments 2. Periosteum. IV discs, ligaments, and spinal cord meninges - innervated by the recurrent meningeal nerve (sinuvertebral N). The first branch off the spinal nerve. 3. Sensory Nerves: transmit pain sensation

Scarohorizontal (Sacral) Angle

1. Formed by the horizontal plane by a line drawn parallel to S1 surface -Normal Angle = 15-30 degrees 2. Anterior tilt of sacrum increases this angle

Sacral Vertebrae (Atypical)

1. Fusion of 5 vertebrae - curved convex dorsally 2. Base = top; Apex = bottom 3. Anterior and posterior sacral foramina for spinal nerve rami 4. Median and Lateral Crests 5. Sacral Canal and Hiatus 6.Coruna at distal end of hiatal opening 4. Auricular (ear) surface articulates with pelvis 5. Superior articular facets face dorsally 6. Sacral promontory is the anterior edge of the S1 vertebra 7. The ala is the fusion of 1st sacral transverse processes

Muscles Unilateral Action Producing Lateral Flexion of C2-C7

1. Iliocostalis Cervicis 2. Longissimus Capitis and Cervicis 3. Splenius Capitis and Cervicis 4. Intertransversarii

Muscles Unilateral Action Producing Thoracic and Lumbar Left Lateral Flexion

1. Iliocostalis Thoracis and Lumborum 2. Longissimus Thoracis 3. Multifidus 4. Semispinalis Thoracis 5. Intertransversarii

Muscles Bilateral Action Producing Thoracic and Lumbar Left Rotation

1. Iliocostalis lumborum and thoracic (left side) 2 .Longissimus thoracis (left side) 3. Semispinalis thoracis (right side) 4. Multifidus (right side) 5. Rotatores (right side)

Joints of the Vertebral Column

1. Interbody Joints 2. Vertebral Arch Joints 3. Craniovertebral Joints 4. Costovertebral and Costotransverse joints (studied with thorax) 5. Sacroiliac. Joints (studied with the pelvic girdle)

Location of intrinsic (true) back muscles in the trunk

1. Intermediate Layer: Erector spinae muscles are located between the spinous processes and angle of the ribs 2. Deep Layers: transversospinalis and segmental groups are located between the transverse processes and the spinous processes

Individual Muscles of Segmental Group

1. Interspinales: -Attachments: to adjacent spinous proc. -2 mm on either side of interspinous ligament 2. Levatores Costarum: -Attachments: from post. rib to trans. proc. of segment above -Action: rib elevation 3. Intertransversarii: -Attachments: to adjacent transverse proc. -Action: Lateral flexion of the spine

Additional Structures in Suboccipital Region

1. Lesser Occipital N 2. Greater auricular N 3. Least (3rd) Occipital N 4. Greater Occipital N

Uncovertebral (Lateral Interbody) Joints

1. Located at C3-C6 levels at posteriolateral rim of vertebral body 2. Uncinate process articulates with inferolateral rim of superior vertebra 3. Considered synovial joints by some references 4. Helps protect IV discs from herniation 5. Potential for spur formation with Arthrosis

Thoracolumbar Fascia

1. Located deep to the extrinsic back muscles 2. Extends superior to inferior from the thoracic region to the sacrum 3. Extends medial to lateral from the spinous processes to the lateral border of the erector spinae muscles and angle of ribs 4. Thoracic Region: thin sheet; covers deep back muscles; attached medially to spinous processes and laterally to the angle of ribs 5. Lumbar Region: thick sheet; 3 layers - posterior and middle layers cover erector spinae muscles; middle and anterior layers cover quadrates lumborum

Longissimus

1. Located medial to iliocostalis and extending from lumbar to cranium 2. 3 Regional Components: -Thoracis: from common tendon - lumbar transverse processes to thoracic transverse processes and lower 9-10 ribs -Cervicis: from transverse proc. of T1-5 and C5-7 to mastoid process -Capitis: From transverse proc. of T1-C5 to mastoid process -Actions: extensor, lateral flexor, ipsilateral rotator of the head

Iliocostalis

1. Located most lateral extending from sacrum to cervical spine 2. 3 regional components - named for area of insertion of fascicles -Lumborum: from common tendon - sacrum, posterior iliac crest, lumbar spinous processes; to ribs 7-12 -Thoracis: from ribs 7-12; to ribs 1-6 -Cervicis: from ribs 3-6; to C4-6 transverse processes 3. Most prominent in lumbar area 4. Action: extensor, ipsilateral rotator, lateral flexor

Vertebral Column Description and Overview

1. Location: Skull to apex of coccyx 2. Components: vertebrae and intervertebral discs 3. Main part of axial skeleton - vertebral column, articulated skull, ribs, and sternum 4. Adult column approximately 75 cm (30 inches) in length 5. 75% of length = vertebrae; 25% = discs 6. Four curves - 2 lordotic (cervical and lumbar); 2 kyphotic (thoracic and sacral) 7. 5 regions; 33 vertebrae 8. 23 Intervertebral discs -Non at the A/O joint, AA joint, sacrum, or coccyx -6 cervical, 12 thoracic, 5 lumbar 9. 25 vertebrae articulate with synovial zygapophysial (facet) joints (4 joints per vertebra) -Control the direction of vertebral motion

4 Occipital Muscles

1. LocationL: posterior neck, between occiput and axis (C2); deep to semispinalis capitus 2. Recuts capitis posterior minor 3. Rectus capitis posterior major 4. Obliquus Capitis Superior (Superior Oblique) 5. Obliquus Capitis Inferior (Inferior Oblique) 6. Innervation: C1 Posterior Ramus (Suboccipital N.)

Lumbar Vertebrae Features

1. Massive bodies 2. Small vertebral foramen 3. Broad, short spinous processes 4. Articular facets aligned in sagittal plane 5. Mammillary Processes: for muscle attachment -These bear the most weight -Used more for flexion and extension

Spinalis

1. Most medial, extending from upper lumbar to skull 2. 3 components: -Thoracis: spinous processes from lumbar to thoracic -Cervicis: spinous processes from lower cervical/thoracic to upperr cervial (often absent) -Capitus: blends with semispinalis capitus 3. Actions: extensor 4. Best found in the thoracic area; blends with longissimus

Semispinalis - Transversospinalis Group

1. Most superficial, extending from thorax to cranium (1/2 of vert. column) NOT FOUND IN LUMBAR AREA 2. 3 Regional Components: -Thoracis and Cervicis: from transverse proc. of thoracic and cervical below to 6 cervical and thoracic spinous processes 4-6 vertebrae above. --Actions: extension and contralateral rotation of neck and trunk -Capitus: Largest posterior neck muscles; deep to splenius muscles. From transverse proc. of upper thoracic and lower cervial to occiput. --Actions: Head extension and contralateral rotation

Zygapophyseal (Facet) Joints

1. Most vertebral column motion at these joints 2. Planar type synovial joints 3. Gliding motion 4. Alignment of articular surfaces determine direction of motion 5. Cervical and lumbar facet joints bear some weight

Quadratus Lumborum

1. NOT A DEEP BACK MUSCLE 2. Location: Between iliac crest and 12th rib ANTERIOR to thoracolumbar fascia 3. Actions: Ipsilateral lateral flexor of trunk; Respiration (stabilizes diaphragm), ipsilateral pelvic hike (contralateral pelvic drop) 5. Innervation: T12-L2 Ventral Primary Rami

Atlas (C1) Features

1. No body; No spinous process; Widest of all cervical vert.; lamina replaced by posterior arch. Large lateral masses with large superior facets replace the body; foramen for dens

Median A/A (C1, 2) Articulation

1. Odontoid process (dens) articulates with ant. arch of C1 2. Located in front of the spinal cord 3. Held in place by strong ligaments 4. Forms 2 joint cavities

Suboccipital (Craniovertebral) Region

1. Paired pyramidal shaped spaces 2. Location: posterior neck between the external occipital protuberance and the C1 and 2 vert. 3. Deep to the traps, SCM, splenius capitus, and semispinalis capitus 4. Each unilateral space contains a suboccipital triangle, 4 muscles, 2 nerves, and 2 arteries

Venous Drainage of the Vertebral Column

1. Paralells AA. Supply. Internal and External venous plexuses collect blood from the vertebrae 2. The blood is then drained into veins of the neck and segmental veins of the trunk

Sympathetic Post-Ganglionic Fibers

1. Post-ganglionic fibers travel from the sympathetic trunk to the spinal nerve in GRAY Rami Communicantes -Post-gangionic fibers are distributed in both dorsal and ventral rami OR travel along blood vessels (in the head and abdomen) to reach smooth muscles and sweat glands -Post-ganglionic fibers of the cervical region leave the sympathetic chain to travel to head, lungs, and heart (cardiac nerves or cardiopulmonary splanchnic nerves) 4. Pre-ganglionic fibers of the splanchnic nerves synapse in ganglia around the great vessels and the post-ganglionic fibers are then distributed within the abdomen and pelvis

Nucleus Pulposis Structure and Function

1. Posterior location 2. Attaches to vertebral endplates comprised of hyaline cartilage and fibrocartilage 3. 88% water 4. Avascular structure 5. Provides shock distribution, flexibility and resiliency to the vertebral column

Intrinsic Superficial Layer - Splenius Muscles

1. Posterior neck, deep to traps 2. Broad and thick 3. Fiber direction - superolateral from midline 4. 2 Components: capitis and cervicis 5. Located superficial to the deep (nuchal) fascia; covers the deep cervical muscles

Functions of the Vertebral Column

1. Protects the spinal cord and nerves 2. Supports body weight superior to the pelvis 3. Provides an extended base on which the head can move 4. Provides a semi-rigid yet flexible axis for the body 5. Important role in posture alignment and locomotion

Back and Posterior Neck Muscles that Ipsilaterally Rotate the Spine

1. Rectus Capitis Posterior Major 2. Inferior Oblique 3. Splenius Capitus and Cervicis 4. Longissimus Thoracis, Cervicis, and Capitus

Back and Posterior Neck Muscles that Extend the Spine

1. Rectus Capitis Posterior Major and Minor 2. Superior Oblique 3. Interspinales 4. Mutifidus 5. Semispinalis Capitis, Cervicis, and Thoracis 6. Splenius Capitis and Cervicis 7. Spinalis 8. Longissimus Thoracis, Cervicis, and Capitis 9. Iliocostalis Lumborum, Thoracis, and Cervicis

Back and Posterior Neck Muscles Producing Extension at the O/A Joint

1. Rectus Capitis Posterior Major and Minor 2. Superior Oblique 3. Semispinalis Capitis 4. Splenius Capitis 5. Longissimus Capitis

Attachments of the Suboccipital Muscles

1. Rectus Capitis Posterior Minor: -From C1 post. tub to occiput -Crosses O/A jt. 2. Rectus Capitis Posterior Major -From C2 spin. proc. to occiput -Crosses O/A jt. 3. Obliquus Capitis Superior: -From C1 trans. proc. to occiput -Crosses O/A jt. 4. Obliquus Capitis Inferior: -From C2 spin. proc. to C1 trans. proc. -Crosses A/A jt.

Back and Posterior Neck Muscles that Contralaterally Rotate the Spine

1. Rotatores 2. Semispinalis Thoracis, Cervicis, and Capitus 3. Multifidus

Intermediate Layer of Intrinsic Back Muscles

1. Sacrospinalis (Erector Spinae) 2. Extent: from sacrum to cranium 3. Location: between spinous process and angles of ribs 4. Largest, longest, and strongest group of the true back muscles 5. Primary trunk extensor. Also an ipsilateral rotator and lateral flexor 6. Composed of 3 muscle columns with fascicles spanning 6-8 vertebrae: -Iliocostalis: most lateral location -Longissimus: intermediate location -Spinalis: most medial location

Back Posterior Neck Muscles Producing Extension of C2-C7 Intervertebral Joints

1. Semispinalis and Iliocostalis cervicis 2. Splenius Cervicis 3. Splenius Capitis 4. Spinalis Cervicis 5. Mutifidus 6. Longissimus Capitis 7. Semispinalis Capitis

Segmental Group of Intrinsic Back Muscles

1. Small and deep muscles that attach to adjacent vertebral segments 2. Probably play a role in posture monitoring and control due to high content of proprioceptors 3. 3 muscles in this group: -Interspinales: cervical (most distinct) and lumbar -Levator costarum: only in thoracic region -INtertransversarii: cervical (most distinct) and lumbar

Thoracic Vertebrae Features

1. Small, round vertebral foramen 2. Backswept transverse. processes 3. Heart shaped vertebral bodies 4. Downswept spinous processes 5. Articular facets aligned in frontal plane (superior and inferior) 6. Costal articular facets

Rotatores - Transversospinalis Group

1. Smallest and deepest of the group. Found consistently in the thoracic spine; Inconsistently in the cervical and lumbar spine 2. Attachments: From transverse proc. below, to lamina of vert. 1-2 segments above 3. Rotatores Brevis (1 segment) and Longus (2 segments) muscles can be identified 4. Actions: Contralateral rotators of the spine; Most likely function in posture control due to high content of proprioceptors

Vertebral (spinal) Canal

1. Spinal cord ends at L1, 2 vertebral levels of the column 2. Cauda Equina occupies the canal inferior to L1, 2 3. Spinal nerves exit the canal through appropriate segmental intervertebral foramina

Splenius Muscles - Attachments and Actions

1. Splenius Cervicis: from T3-6 spinous processes; to C1-3 transverse processes 2. Splenius Capitis: from C7-T3 spinous processes to mastoid process of skull -Bilateral Action: Head and neck extension -Unilateral Action: ipsilateral rotation and lateral flexion (ipsilateral sidebending)

Back and Posterior Neck Muscles Producing Right Rotation of C2-C7

1. Splenius cervicis and capitis (right side) 2. Longissimus Capitis (right side) 3. Semispinalis Cervicis and Capitis (Left side) 4. Multifidus (left side) 5. Rotatores (left side)

Ligamentum Nuchae

1. Strong, broad, median band; posterior neck 2. Attaches: from base of skull to all cervical spinous processes 3. Fibroelastic tissue 4. Serves as attachment for muscles 5. Limits cervical flexion 6. Supensory ligament for quadrupeds

Axis (C2) Features

1. Strongest cervical vertebra. Odontoid process (Dens); 2 ;are biconvex superior facets; axis for rotation of head and C1; most cervical rotation occurs at C1, C2 joint

Location of Muscles of Posterior Neck

1. Superficial Layer: splenius: spinous processes to transverse processes and to occiput 2. Deep Layer: transversospinalis muscles; same attachment as muscles in trunk plus semispinalis capitus to occiput 3. All capitis muscles - i.e. longissimus capitis (3) - attach to the posterior/inferior aspect of skull or mastoid process. EXCEPTION = one subocciptal muscle

Back and Posterior Neck Muscles that Laterally Flex the Spine - Unilateral Action

1. Superior Oblique 2. Intertransversarii 3. Splenius Capitus and Cervicis 4. Longissimus Thoracis, Cervicis, and Capitus 5. Iliocostalis Lumborum, Thoracis, and Cervicis

Ligaments of the Vertebral Arches

1. Supraspinous ligament 2. Interspinous ligament 3. Ligamentum Flavum 4. Intertransverse Ligament 5. Ligamentum Nuchae 6. Support and protect the arch; guide and restrict movements 7. Limit vertebral flexion; thus help protect intervertebral discs

Anterior A/O Membrane

Attaches between anterior arch of C1 and anterior rim of foramen magnum. Limits cranial extension

Posterior A/O Membrane

Attaches between posterior arch of C1 and posterior margin of foramen magnum. Limits cranial flexion

C4/C5

The 5th cervical nerve exits through the IVF formed by which functional unit?

AJV

The Carotid Sheath contains all of the following except: A. Common carotid B. IJV C. Vagus N D. AJV

Submandibular

The Hypoglossal N is located in which of the following triangles?

L4

The L4 nerve root exits below the pedicle of which vertebra?

Mylohyoid

The ansa cervicalis innervates all of the following muscles EXCEPT:

Vagus

The recurrent laryngeal N is a branch of what N?

-Vertebral A -Suboccipital N

What 2 NV structures run through the sub occipital triangle of the neck?

-Intertransversarii -Interspinalis -Levator Costarum

What 3 groups of muscles are part of the deep segmental group of the spine?

-Ipsilateral SB -Contralateral rotation -Flex the upper C spine -Extend the C spine

What are the unilateral actions of the SCM?

Transversospinalis

What group of muscles will rotate the spine contralaterally?

Pars articularis

What is part of the vertebra that if injured will allow forward slippage of another vertebra?

Ventral Primary Rami

What is the innervation for the serrates posterior superior or inferior, dorsal or ventral primary rami?

Longissimus Capitis

What is the most lateral muscle attaching to the head?

Spinalis

What is the most medial erector spinae muscle?

Nucleus Pulposis

What is the name of the inner part of the vertebral discs?

Rotation

What is the primary motion in the thoracic spine due to the orientation of the facets?

Posterior longitudinal ligament

What ligament in the spine is directly behind the vertebral bodies?

Ligamentum Flavum

What ligament is now behind the spinal cord and just in front of the lamina of the vertebrae?

QL (ventral primary rami)

What muscle attaches from the lower ribs, lumbar iliac crest, trans. proc. can SB the spine and assist in anterior pelvic tilt?

Lumbar

What part of the spine would you expect flexion and extension to be the primary movement?

Pedicle

What part of the vertebra forms the intervertebral foramen?

Frontal

What plane are the facet joints primarily oriented in the thoracic spine?

Longus Colli

Which muscle attaches to T3 and the atlas a it courses deep in the anterior neck?

Hyoglossus

Which muscle lies deep and lateral to the mylohyoid?

ECA

Which of the following A supply blood to the upper neck, the face, and the scalp?

E. None of the above

Which of the following ligaments has the highest portion of elastic fibers? A. Anterior Longitudinal B. Posterior Longitudinal C. Supraspinous D. Interspinous E. None of the above

Ipsilateral Rotation

Which of the following motions is the primary motion created by the inferior oblique?

Mylohyoid

Which of the following muscles elevate the hyoid?

T7

Which of the following vertebra has the longest spinous process?

Inferior Oblique

Which of the sub occipital muscles would be the primary rotator of the A/A joint?

L2/L3

Which spinal segment has the greatest degree of flexion and extension?

Submandibular

Which triangle is formed by the anterior and posterior bellies of the digastric and the inferior border of the mandible?

TRUE

True or False. The C2/C3 spinal segment encompasses the most cranial cervical disc?

TRUE

True or False. The ansa cervicalis is a motor plexus that is comprised from the ventral rami of C1, 2, and 3?

FALSE

True or False. The greater occipital N innervates the rec cap post major and minor muscles on its way to providing the back of the head with cutaneous innervation?

TRUE

True or False. The vertebral A originates from the subclavian A and terminates in the Basilar A?

Craniovertebral Joints

Two joints: -A/A -O/A

Sympathetic Efferents of ANS

-2 Neuron System: SHORT pre-ganglionic and LONG post ganglionic neurons -Pre-ganglionic fibers originate in lateral horn of spinal cord (T1 through L2) -Pre-ganglionic fibers travel in WHITE Rami Cimmunicantes to reach the spinal nerve (through ventral ramus) and then to sympathetic chain or trunk -Ganglia of Sympathetic N system form chains.trunks that lie on sides of vertebral column from cervical to sacral regions (paravertebral ganglia)

Vertebral Interbody Joints

-2 Types: 1. Intervertebral Joints 2. Lateral Interbody (uncovertebral) joints (only in cervical spine)

General Visceral Efferents (GVE)

-ANS (sympathetic and parasympatheticO -Transmit motor impulses to smooth muscle and glandular tissue (e.g. cardiac muscle)

ASIA Scale

-Americal Spinal Injury Association -UE: Foster -LE combination of Forester, Keegan and Garrett -This is used most often clinically

Bony Alignment Stabilization of L5-S1 Junction

-Anterior - Posterior Alignment 1. Apophyseal (facet) joint alignment 2. L5 inferior facet surface faces anteriorly and laterally 3. S1 Superior facet surfaces posteriorly and medially 4. Frontal plane alignment assists in blocking anterior shear forces at L5-S1

Submandibular Triangle Borders

-Anterior Digastric -Posterior Digastric -Mandible

Muscular Triangle Contents

-Anterior Jugular V -Infrahyoid muscles -Thyroid Gland -Larynx -Trachea

Mylohyoid Muscle

-Attachments: --Mandible --Raphe --Hyoid -Actions: --Elevates hyoid, oral floor, and tongue

Suprahyoid Region

-Bilateral submandibular triangles and the submental triangle -Submandibular: submandibular gland, nodes, Hypoglossal N, Facial A, V, and digastric, stylohyoid, hypoglossus muscles -Digastric --Anterior Belly (CN V [5]), mandible --Posterior Belly (CN VII [7]), mastoid process of temporal bone --Elevates hyoid bone, stabilizes it, depresses mandible against resistance -Stylohyoid (CN VII[7]): --Elevates and retracts the hyoid

Ansa Cervicalis Inferior Root

-Branches from C2 and C3 spinal nerves -Descends lateral to IJV, then crosses IJV to join the superior root

CNS vs PNS

-CNS --Brain --Spinal cord -PNS --Nerve fibers and cell bodies outside of the CNS --31 pairs of spinal nerves --12 pairs of cranial nerves

Carotid Sheath

-Common Carotid A -Internal Jugular V -Vagus N -Carotid Sinus N - branch of CN IX --Carotid Sinus: Baroreceptor in ICA --Carotid Body: chemoreceptor in posterior wall of Common Carotid A (especially sensitive to oxygen)

Carotid Triangle Contents

-Common Carotid A bifurcation (carotid sinus N) -Ansa cervicalis -External Carotid A (ECA) -Internal Carotid A (ICA) -Internal Jugular V (IJV) -Vagus N (CN 10) -Hypoglossal N (CN 12) -Spinal Accessory N (11)

Carotid Sheath

-Condensaion of prevertebral and pretracheal fascia, dense fibrous investment around the internal jugular vein, common carotid artery and its bifurcation, the vagus nerve, and ansa cervicalis (cervical plexus). Extends from the base of the cranium to the root of the neck -Associated Structures: --Deep cervical lymph nodes --Carotid sinus and nerve --Periarterial sympathetic plexus

Parasympathetic Cranial Pre-Ganglionic Fibers

-Cranial Pre-ganglionic Fibers: synapse in ganglia in head and hence post-ganglionic fibers stay in head (III, VII) and neck (CN IX) except for Cranial Nerve X (Vagus Nerve) -The pre-ganglionic parasympathetic fibers of the vagus N: travel to thorax and abdomen. The post-ganglionics then travel from the ganglia to the organs (no names for these ganglia)

Spinal Cord Features and Structures

-Denticulate Ligaments: attached I pairs throughout the length of the cord (toothlike projections) -Spinal Cord Enlargements: Cervical (C5-T1) and Lumbar (L2-S3) -Conus Medullaris (tip of the spinal cord where it ends [L1-L2 level]) -Filum Terminale: to coccyx -Cauda Equina "Horse's Tail": Collection of nerve roots surrounding film terminale

Dorsal and Ventral Rami

-Each spinal nerve branches into a dorsal and ventral ramus after leaving the IVF -Ventral Rami: lateral and anterior, muscles of limbs and trunk (except for back), skin of limbs, and trunk (except for skin innervated by dorsal rami) --Mix to form plexuses --Carry sensory and motor fibers to and from body wall/limbs including sympathetics -Dorsal Rami: posterior, back muscles and skin of back , neck, and part of scalp --Most do not mix (i.e. no plexus forms) --Carry sensory and motor fibers to and from body wall including sympathetics

Relationship Between Spinal Canal and Spinal Nerves

-Each spinal nerve exits at the proper vertebral level through the intervertebral foramen (IVF) -Fairly equal exit form spinal cord segment to IVF in cervical region -Oblique course for rest of spinal nerves

Visceral Compartment

-Encloses the: --Infrahyoid mm (anterior triangle) --Trachea, esophagus and thyroid gland (visceral tube) --Continuous superiorly with the buccopharyngeal fascia (pharynx)

Spinal Cord Spaces

-Epidural: above dura mater, epidural anesthesia -Subdural: under dura mater (between dura and arachnoid mater), small -Subarachnoid: Under arachnoid mater (between arachnoid and Pia mater), largest space, filled with CSF location for spinal tap (lumbar puncture) -The lumbar cistern is a large subarachnoid space full of CSF

Ansa Cervicalis

-Formation of nerves from C1 to C3 -C1 and CN XII (Hypoglossal N) make up part of the formation along with C2, 3 -C1 fibers leave the CN XII sheath to form superior root of ansa deep to posterior digastric and anterior to Common Carotid A

Neck: Visceral Compartment and Root of Neck

-From superficial to Deep: --Veins: Brachiocephalic and Internal Jugular VV (Note length of Lt Brachiocephalic V) --Arteries: Right side - brachiocephalic Trunk with Rt Subclavian A and Rt Common Carotid A (note origin go AA from the Arch of the Aorta different on left) --Nerves: Vagus N between the V and A, recurrent branch between trachea and esophagus --Viscera: Thyroid and Parathyroid glands, trachea, and esophagus --Deep muscles --Cervical vertebrae

Suprahyoid Region

-Geniohyoid -(C1 via CN XII) -Mandible to hyoid -Deep to mylohyoid -Pulls hyoid anteriorly and superiorly shortens floor of mouth, widens pharynx

Submental Triangle Borders

-Hyoid Bone -Anterior bellies of R and L Digastric Muscles -Floor = mylohyoid muscle

Landmarks

-Hyoid Bone (C3) -Larynx/Trachea --Thyroid Cartilage (C4, 5), laryngeal prominence --Cricoid Cartilage (C6) -Larynx becomes Trachea at inferior border of cricoid cartilage -Trachea bifurcates at T4

Carotid Sinus Syndrome

-Hyper-sensitive sinus -Syncope -Can treat by surgical denervation

Vertebral Column Movements

1. Facet Joint Alignment -Cervical: oblique upwards from horizontal plane -Thoracic: Frontal plane -Lumbar: Sagittal plane -Determines the direction of movements occurring at the facet joints

Intrinsic Back Muscles - Features

1. 3 layers from superficial to deep 2. Superficial: splenius capitus and cervicis (posterior neck) 3. Intermediate: erector spinae (sarcospinalis) - iliocostalis, longissimus, and spinalis 4. Deep (2) -Transversospinalis group - semispinalis, multifidis, and rotatores -Segmental group - interspinalis, intertransversarii, and levator costarum 5. These back muscles extend from the sacrum to the cranium 6. The largest and longest muscles (erector spinae) are most superficial and each group becomes smaller and shorter in length with deeper location 7. Muscle origins are caudal; insertions are cranial 8. Action: extensors, rotators, and lateral flexors of the vertebral column. Must consider both unilateral and bilateral actions 9. Thoracic and lumbar muscles are enclosed within the thoracolumbar fascia

Cervical Spine Overview

1. 7 Vertebrae - 2 atypical; 5 typical 2. 2 anatomical and functional groups - upper (O/A; C1, 2); and Lower (C2-C7) cervical 3. 6 discs: C2-T1; no disc between O/A and A/A segments; disc named for vertebra above; (C2 disc between C2, 3 vertebrae) 4. Uncinate Processes: Lateral elevations of superior surface of the vertebral body (C3-6) -Form uncovertebral (lateral interbody; von Lischka) joints

Suboccipital Triangle

1. A muscular triangle located deep to the semispinalis capitus muscles (roof of the triangle) 2. Medial Boundary: rectus capitis posterior major 3. Inferior Boundary: Inferior Oblique 4. Lateral Boundary: Superior Oblique 5. Floor: Posterior Atlanta-occipital membrane 6. Contents: vertebral A. and Suboccipital N

Two Ligaments Support the Bodies Inferior to C1 Vertebra

1. Anterior Longitudinal: becomes anterior A/O membrane superior to C1 2. Posterior Longitudinal: Becomes tectorial membrane superior to C1

O/A Joint

1. Articulation of superior surfaces of C1 lateral masses with occipital condyles 2. Permit nodding type extension (10 deg.) > flexion (5 deg.); little side bending 3. Thin, loose capsules; synovial joints 4. Connected by anterior an posterior A/O membranes. Anterior membrane is stronger

Insterpinous Ligament

1. Attaches between spinous processes from their root to their apex 2. Thin, membranous structure 3. Restricts flexion

Posterior Longitudinal Ligament

1. Attaches more to posterior discs, less to posterior vertebral bodies 2. Much thinner than anterior longitudinal ligament 3. Runs from sacrum to C2 4. Becomes tectorial membrane at C2, passes through foramen magnum, attaches to cranium 5. Function: Limits vertebral flexion; helps prevent posterior disc protrusions

Anterior Longitudinal Ligament

1. Attaches to anterior surface of vertebrae and discs 2. Runs the length of vertebral column - ventral sacrum to ant. tubercle C1 3. Becomes anterior A/O membrane to C1 4. Fucntion: Limits vertebral extension (the only one); stabilizes interbody joints

Intervertebral Discs

1. Bind vertebrae together 2. Permit limited movement 3. Located anterior to the spinal cord and nerve roots 4. Parts: -Annulus Fibrosis: External fibrous part -Nucleus Pulposis: Internal Semi-gelatinous part

The Vertebral Artery

1. Branch of the subclavian A 2. Passes through transverse foramen from C6 to C1 3. Crosses posterior arch of C1 medially 4. Penetrates posterior A/O membrane, dura, and arachnoid membrane 5. Enters cranium through foramen magnum 6. Forms Basilar A

Cervical Vertebrae Features

1. C1 and C2 Atypical 2. C3-C7 Typical 3. Small oval bodies 4. Large vertebral foramen 5. Bifid spinous processes 6. C7 = Vertebra Prominens 7. Grooved transverse processes with 2 tubercles 8. Transverse foramen 9. Most mobile region of the spine

Multifidus - Transversospinalis Group

1. Deep to semispinalis, extending from sacrum to C2 (axis) 2. Attachments: from transverse proc. below, to spinous proc. 2-4 vertebrae above 3. No regional components (there are no lumborum, thoracic, cervicis, and capitus) 4. Located best in the lumbar and sacral areas 5. Actions: extension and contralateral rotation of the spine

Shape of Intervertebral Discs

1. Discs thicker in cervical and lumbar regions = more motion 2. Disc wedge shaped: thicker anteriorly. Helps form the cervical and lumbar curves

Suboccipital Region - Bony Landmarks for Muscles

1. External Occipital Protuberance 2. Inferior Nuchal Line 3. C1 Vertebra: posterior tubercle and trans. proc. 4. C2 Vertebra: spinous process

Actions of Back and Posterior Neck Muscles

1. The larger, more superficial back muscle (erector spinae, splenius and semispinalis) primarily function to move the vertebral column in the direction of extension 2. All other vertebral motions (flexion, rotation, and side bending) require additional activation of abdominal and other ventrally located muscles of the trunk and neck 3. The deeper, smaller back muscles (multifidus, rotatores, and segmental group) provide axial stabilization, posture control, and proprioception 4. When describing a back muscle's action, one must indicate whether the muscle is acting unilaterally or bilaterally 5. Also must be aware that the transversospinalis group rotates the spine to the opposite side when acting unilaterally

Supraspinous Ligament

1. Tips of spinous processes from sacrum to C7 2. Cord-like structure 3. Continuous with ligamentum nuchal at C7 4. Limits flexion 5. Able to palpate this ligament

Deep Layer of Intrinsic Back Muscles

1. Transversospinalis Group: deep to erector spinae 2. Location: laminar groove (gutter) between spinous and transverse processes 3. Extent: from sacrum to cranium 4. Attachments: from transverse processes to below; to spinous processes above 5. Direction of Fascicles: superiorly from lateral to medial 6. 3 muscles in this group -Semispinalis: most superficial -Multifidus: Deeper -Rotatores: deepest and smallest

Ligamentum Flavum

1. Yellow ligaments - elastin 2. Join vertebral laminae 3. Form part of posterior wall of vertebral canal 4. Thickest in lumbar area 5. Strong, help maintain curves of spine; assist with vertebral extension from flexed position

General Blood Supply to the Vertebral Column

1. vertebral Ascending Cervical AA 2. Segmental AA of trunk and their spinal branches 3. posterior Intercostal AA 4. Subcostal and Lumbar AA 5. Iliolumbar, lateral and median sacral AA

Components of Intervertebral Joints

2 adjacent vertebrae and interposed IV disc

B. Superior Oblique

All of the following muscles attach to C2, EXCEPT: A. Rec Cap Post Major B. Superior Oblique C. Inferior Oblique D. Semispinal is Cervicis

Median A/A Joint

Between dens of C2 and anterior arch of C1. Pivot joint

Segmental AA

Branches of Vertebral AA, Aorta and External Iliac AA

C. Splenius Cervicis

Considering unilateral action, all of the following muscles rotate the spine the contralateral direction, EXCEPT: A. Multifidus B. Rotatores C. Splenius Cervicis D. Upper Traps E. SCM

Sympathetics

Distention, spasm, ischemia

Denticulate Ligaments

Help provide support to the meninges

Pretracheal Layer, Deep Cervical Fascia

Limited to the anterior part of the neck, encloses the muscles and viscera in the anterior neck, extends from the hyoid bone into the thorax where it blends with the fibrous pericardium of the heart.

Parasympathetics

Motility, nausea, vomiting

Thoracic, Lumbar and Sacral Spinal Nerves

Spinal nerves exit BELOW corresponding vertebra (E.g. L5 spinal nerve exits between L5 and S1)

Investing Layer, Deep Cervical Fascia

Surrounds the entire neck deep to the skin and superficial fascia. Splits to enclose the trapezius and SCM. Forms the roof of the anterior and posterior triangles

Ipsilaterally

The erector spinae muscles, do they rotate the spine ipsilaterally or contralaterally?

C3

The common carotid A divides at which spinal level?

C. A/A

The greatest degree of cervical rotation occurs at which functional spinal unit?

C3

The hyoid bone lies at the level of which cervical vertebra?

General Somatic Efferents (GSE)

Transmit motor impulses to muscles