Spinal Anatomy Exam 1

what are the 7 basic functions of the spine

1) Protect spinal cord & nerve roots

2) Passage of spinal nerve to/from spinal cord

3) Support/Stabilize body

4) Developmental origin of ribs

5) Shape/Position body

6) Movement of trunk and limbs (locomotion)

7) Provide horizontal orientation for eye (vision) and vestibular apparatus (balance)

Which somite gives rise to the vertebral column?

-paraxial mesoderm gives rise to somite which forms the sclerotome which forms the vertebral column

where is the intrasclerotomal fissure? what does it form

-between sclerotomites of a perichordal blastema is the intrasclerotomal fissure

-gives rise to perichordal disc (adult IVD)

during the 6th week of development, the ______________undergoes chondrification

-membranous vertebral blastema

--replacement of mesoderm by cartilage

how many chondrification centers are in a vertebra

6

-1 pair in the centrum

-1 par in the arches (right and left)

-1 pair in the TVP (right and left)

during the 7th week, cartilage is replaced by ___________. primary ossification occurs _______ secondary occurs _________

-bone

--primary: before brith

--secondary: between birth and late puberty (11-16 years) and fuse to the rest by age 25

how many primary centers of ossification and how many secondary?

-3 primary (1 centrum and 2 in the arch)

-5 secondary (2 in body and 3 in arch)

--epiphyseal plate, tip of TVP, tip of spinous process

primary centers of ossification grow _________, cartilage decreases until _____ form

-grow toward each other

-decrease until small synchondrosis join remains

synchondroses formed between each centrum and neural arch centers ossification on each side becomes _______

-neurocentral synchondrosis

synchondroses of secondary centers include:

-epiphyseal ring synchondrosis

-tip of TVP synchondrosis

-tip of spinous process synchondrosis

what is a primary curvature of the spine

-kyphotic (posterior, concave)

---thoracic, sarcococcygeal

-you are born with

what is the secondary curvature of the spine

-lordotic (anterior, convex)

--cervical (hold head up) and lumbar (walking)

-develop with milestones

the IVD has a greater _________ height than _______ height in cervical and lumber region which creates a ______ curve

-anterior

-posterior

-lordotic curve

a kyphotic curve is due to height difference of ___________. the ______ height is greater

-due to height difference of vertebral body

-greater posterior height

lateral curvatures of the spine are slight in ______ region. Tend to appear after ______ years of age. Deviations result from?

-slight in upper thoracic region

-appear after 6 years

-deviations from asymmetrical muscle use

lateral curvatures are originally thought to be only associated with?

-handedness

--we realized it my have some genetic factors and or environmental

where do we usually see lateral curvatures?

-usually in thoracic and lumbar regions

--convexity of curve is on the left in left handed people and o the right in right handed people

which part of the IVD attaches vertebral bodies and which part separates them?

-annulus fibrosis attaches

-nucleus pulposis separates

what are some other functions of the IVD (4)

-helps shape the spine

-acts as a powerful ligament

-forms part of the anterior border of vertebral canal and anterior border of IVF

-shock absorber

what makes up the annulus fibrosis of the IVD? nucleus pulposis?

annulus: type 1-2 collagen (restrict movement)

nucleus: water, collagen, proteoglycans (movement)

what are the 2 main things that make up IVD

-proteoglycan gel and collagen fibers

how do you lose water in IVD? how do you get it back?

-water loses volume during the day; 8 hour laying period returns water to IVD and restore height of the spine

*overall height diminished with age

nucleus pulposis becomes more _________ concentration of H2O and proteoglycans ________ with age

-more fibrous

-H2O and proteoglycans decrease

what is a small round projection or protuberance on a bone

tubercle

what is a project5ion or outgrowth of tissue from a larger body

process

what is a small flat surface on a bone

facet

what relates to the joints of the body

articular

what relates to the rib

costal

what does the superior epiphyseal rim do? what attaches here?

-keep IVD within the borders

-ligaments attach here

what does the pedicle do?

-aka superior and inferior vertebral notches

-connect body and arch

-form boundaries of intervertebral foramen!!!

what does the lamina do? what attaches here? what is the clinical significance

-flat, lack of blood supply, and thin (vulnerable)

-ligamentum flavia attaches here

-spondylosis can occur here

what are the veins within the spinal canal

-internal vertebral venous plexus

-anterior spinal vein

-posterior spinal vein

-basivertebral venous formamina

what does the internal vertebral venous plexus do?

-provides alternative route if IVC or jugular veins are comprimised

-surrounds whole vertebrae canal

-in epidural space

what are the arteries in the spinal canal

-segmental artery which goes to ....

-spinal branch which goes to .....

-mixed spinal n OR medullary (feeder) artery.....

-radicular A OR posterior spinal A OR anterior spinal A

which ligaments form the anterior and posterior boundary of the spinal cord

anterior boundary: posterior longitudinal ligament

posterior boundary: ligamentum flavum

the PLL does what? where does it attach?

-prevents hyperflexion and posterior spinal disc herniation

-attaches to body

the ligamentum flavum does what? where does it attach?

-preserve upright posture

-prevent hyperflexion

-straightens spinal column after flexion

-attaches at lamina: vertebral arch

spinal cord and meninges found in vertebral canal until what level?

L2

what is in the epidural, subdural and subarachnoid space?

epidural: external to dura; filled with fat

subdural: potential space between dura and arachnoid (BAD)

subarachnoid: between arachnoid and pia contains CSF

what is the filum terminale? what type of movement does it prevent

-extension of pia mater, anchors cord to sacrum and coccyx

-prevents vertical movement

what are denticulate ligaments? what type of movement does it prevent?

-extension of pia mater, anchors cord laterally to dura mater

-prevents side movement

the IVD develops from?

notochord and sclerotomes

what does the nucleus pulposis develop from?

-notochordal tissue

what is the composition of the cartilaginous end plates

-hyaline cartilage (attached at centrum

-fibrocartilage (attached at IVD)

what is the function of the cartilaginous end plates

-prevents centrum from undergoing atrophy and pressure

-keeps IVD within anatomical borders

-extremely porous

-diffusion of gases, nutrients, waste material

what is the joint classification of intervertebral discs

cartilaginous (amphiarthrosis) symphysis joint

--bones united by fibrocartilage

what is the innervation of anterior intervertebral discs

-afferent, sympathetic branches from sympathetic trunk

what is the innervation of posterior intervertebral discs

-receives input from sinu-vertebral nerve (recurrent meningeal)

-ventral ramus and gray ramus

-nociceptors (sensitive to annular tears)

what is the innervation of lateral intervertebral discs

-receives from gray ramus communicans

what are the boundaries of intervertebral foramina (superior, inferior, anterior, posterior)

superior: inferior vertebral notch of segment above

inferior: superior vertebral notch of segment below

anterior: IVD, vertebral bodies, PLL

posterior: prezygapophysis, postzygapophysis, capsular ligament, ligamentum flavum

what are the contents of intervertebral foramina

-spinal nerves and roots

-arteries, veins, lymphatics

-ligaments

neural tissue of IVF fills ____% what are the surrounding strucures?

8-50%

-ventral and dorsal nerve roots

-dorsal root ganglion

-mixed spinal nerve

spinal branch arteries arise from _______ in the IVF? what are branches that are given off before entering IVF

-segmental artery

-osseous branches

-anterior/posterior spinal plexus

What is the artery of Adamkiewicz? where does it enter? what does it supply

"anterior medullary feeder artery"

-enters T9/T19 IVF; 77% on left side

-principle supplies of lumbar enlargement L2-S3

the artery of AK (Adamkiewicz) is the only major arterial supply to ?

-anterior spinal artery inferior to entry

75% of thoracic IVD herniations occur below?

T8

-artery often compromised

-common signal of involuntary urination

Intervertebral veins are part of the IVF and are an anastomosis of

-various veins with epidural and subarachnoid space

intervertebral veins merge with??? and drain into???

-merge with external vertebral venous plexus and drain into segmental vein

lymphatic capillaries of the IVF arise in ______ space. vessels form near??

-arise in epidural space

-vessels form near IVF

transforaminal ligaments attach?

-vertebral bodies to articular process

superior transforaminal ligaments attach vertebral body to _______ of same verteba

-inferior articular process

middle transforaminal ligaments attaches IVD to _______ of segment above

-inferior articular process

inferior transforaminal ligaments attach vertebral body to _______ of same verteba

-superior articular process

corpotransverse ligaments attach?

attach vertebral bodies to TVP

superior corpotransverse attaches vertebral body and IVD to

-TVP of vertebra BELOW

inferior corpotransverse attaches vertebral body and IVD to

-TVP of vertebra ABOVE

what is a synarthrosis joint?

-no movement

-aka fibrous

-skull sutures

what is an amphiarthrosis joint

-slight movement

-aka cartilaginous

-IVD

what is a diarthrosis joint

-free movement

-synovial fluid filled cavity

-shoulder joint

what is a fibrous joints and movements allowed

-more than 2 bony surfaces connected by a thin layer of dense (fibrous) CT

what are some examples of fibrous joints

-sutures of skull

-syndesmosis

-gomphosis (roots of teeth with alveoli of mandible/maxilla)

-schindylesis

where are sutures located? can they move? what is the ligament called?

-only between skull bones

-NO movement in adults, slight movement in children

-sutural ligament

what are the 4 sutures of the skull and when do they ossify

-metopic= 1st year

-coronal= 24 years

-sagittal= 21-30 years

-lambdoid= 26 years

syndesmosis joints contain what 3 things?

-interosseous membrane

-collagen fibers- white fibrous CT (PLL and ALL)

-elastic fibers- ligamentum flavum

most ligamentous joints of the spine demonstrate measurable motion which is an example of ?

amphiarthrosis

gomphosis joint is a _________ process into a socket

conical

the only schindylesis example in the body is when what 2 parts articulate?

-rostrum of sphenoid and ala of vomer

what is a cartilaginous joint and what are some examples

-cartilage fills space between opposing bones

-symphysis (fibrocartilage)

-synchondrosis (hyaline)

what are 2 examples of a synchondrosis cartilaginous joint

-cartilaginous epiphyseal plate (temporary)

-costochondral joint

symphysis cartilaginous joints occur along ____ plane and is a _____ joint.

-median plane

-permanent joint

what are some examples of symphysis cartilaginous joints

-IVD

-pubic symphysis (provides shock absorption and stability to pelvis during birth; relaxin increases mobility at symphysis

what is a synovial joints and its 4 parts

-joint cavity filled with synovial fluid

-articular capsule

-articular cartilage

-synovial membrane

-synovial fluid

how are synovial joints classified (3 things)

-number of bones or articular surfaces

-types of movement allowed by joint

-morphological appearance

how do you distinguish between simple, complex, and compound in a synovial joint classification

simple: opposing bones (fingers and toes)

complex: joint cavity divided into 2 compartments (knee)

compound: more than 2 bones (tibia, fibula, femur)

what is a synovial plane joint, what movements are allowed and examples

-diarthrosis arthroidal

-flat plane or slightly concave-convex

-gliding and translation movement

-costovertebral/sygapophyseal/facet/zygapophysial

what is a synovial saddle joint, what movements are allowed and examples

-diarthrosis sellar

-flexion/extension/adduction/abduction/circumduction

-carpometacarpal joint

what is a synovial ellipsoidal joint, what movements are allowed and examples

-diarthrosis condyloid

-flexion/extension/lateral bending

-atlanto-occipital/metacarpophalangeal joint

what is a synovial pivot joint, what movements are allowed and examples

-diarthrosis trochoid

-proximal radioulnar/median atlanto-axial joint (limited flexion/extension)

-UNIAXIAL

what is a synovial ball and socket joint, what movements are allowed and examples

-spheroid

-all movments

-shoulder/hip joint

-MULTIAXIAL

what is a synovial hinge joint, what movements are allowed and examples

-ginglymoid

-flexion/extension

-IP joints hands and feet/humeroulnar

-UNIAXIAL

articular capsule location and function

-contains 4 types of mechanoreceptors located in superficial or deep layers of joint capsule and ligaments

type 1-3 mechanoreceptors in articular capsule are encapsulated or not??? what is their function?

-encapsulated

-proprioceptive function

type 1-3 mechanoreceptors are in charge of _______ movements and the maintenance of _____________ by monitoring?

-coordination and control of movements

-maintenance of upright posture

-monitor stationary position and movements of body parts

type 1-3 mechanoreceptors relay into to the? and provide information about?

CNS

-direction, velocity, and initiation of joint movements

type 1=

type 2=

type 3=

type 1= ruffini (mvmt at rest)

type 2= paciniann (normal mvmt)

type 3= golgi tendon organ (extreme mvmt)

type 4 mechanoreceptors in articular capsule are encapsulated or not??? what is their function?

-non-encapsulated

-unmyelinated free nerve endings (nocioceptors)

what do type 4 mechanoreceptors respond to

-potential mechanical injury or inflammation processes

articular surfaces are covered with _________

-hyaline cartilage

--avascular, lacks lymphatics and innervation; no potential for growth and repair

nutrition/waste elimination provided by _______

-synovial fluid

--BV in synovial membrane, and or sinuses of bone marrow

what is a major component of articular cartilage

proteoglycans and GAGs (water retention)