Anthrology & Syndesmology Of The Spine Flashcards
Define anthrology.
The study of joints and articulations
Define syndesmology.
The study of ligaments
How would we classify a joint that has little to no movement? Give an example.
Synarthrosis. Ex. Bones of the skull at their fusion
How would we classify a joint that has a wide range of movement? Give an example.
Diarthrosis. Ex. Glenohumeral joint
How do we classify a joint that moves slight amounts? Give an example.
Amphiarthrosis. ex. IVDs
What is a fibrous joint? Give an example.
Articulating surfaces connected by fibrous tissue. Ex. Teeth
What is a synovial joint? Give an example.
Articulating surfaces covered by cartilage, but NOT directly connected.
Ex. Z joints
What are the features of a synovial joint?
Synovial cavity, joint capsule, and extracapsular ligaments. Often lined w/ hyaline cartilage.
What is a cartilaginous joint? Give an example.
Articulating surfaces connected by cartilage. Ex. Pubic symphysis. Central body joints.
How would we classify the movement of a central joint (inter body joint)?
Amphiarthrosis.
Where would we find a central joint?
Between adjacent vertebral bodies and IVD. “Inter body joint”.
How would we classify the connective tissue of a central joint (inter body joint)?
Cartilaginous joint.
How would we classify the movement of a zygapophyseal joint?
Diathrosis.
How would we classify the connective tissue of a zygapophyseal joint?
Synovial joint.
Where would we find a zygapophyseal joint?
Between the superior articular process of the inferior vertebrae, and the inferior articular process of the superior vertebrae.
Where are the atypical central joints?
CO-C1, C1-C2, sacral segments, coccygeal segments.
What do we call the “central joint” of CO-C1?
Atlanto-occipital joint.
What do we call the “central joint” of C1-C2?
Atlanto-axial joint.
Why don’t we find central joints in the sacrum or coccyx?
The joints are fused in both structures, in most people. In others, rudimentary discs may be present but they are not true central joints.
What kind of connective tissue makes up the IVDs?
Fibrocartilage. Sometimes hyaline.
How many IVDs do we have in the spinal column?
23 total - 6C, 12T, 5L
How do we name an IVD?
Include the vertebrae they separate. Ex. C4-C5 IVD
Describe the relative shape of the IVDs.
Thickest in L, thinnest in T.
Thicker anteriorly in lumbar and cervical regions, helps to form lordotic curves.
What are the two anatomical features of an IVD?
Nucleus pulposus (inner) and anulus fibrosus (outer).
Describe the structural features of the anulus fibrosus.
Outer concentric fibrocartilaginous rings. “Basket weave” for strength.
What is the function of the anulus fibrosus?
Functions as a ligament to bind vertebral bodies. Retains nucleus pulposus.
Which structure is most similar to that of an embryonic notochord?
Nucleus pulposus of the IVDs.
What is in the nucleus pulposus?
Collagen in mucopolysaccharide base.
Explain the hydrophilic nature of the nucleus pulposus.
Imbibes water while laying down due to hydrophilic tendencies. When standing and sitting, the force of gravity disperses the water, causing the IVD to shrink. With age the nucleus pulposus becomes dehydrated and fibrous, accounting for height loss up to 25%
What is a vertebral end plate?
Interface of bone and fibrocartilage adjacent to upper and lower surfaces of successive vertebral bodies. Collagen fibers are continuous between the anulus fibrosis and the VEPs
T/F
The VEP is thickest peripherally.
False - ~3mm thick centrally, 1mm thick peripherally.
What is the purpose of the VEPs?
Porous to allow transport of water and nutrients from vertebral bodies to IVDs. Allows waste to exit
Where does the IVD adhere to?
Anular epiphysis on the upper and lower surfaces of the adjacent vertebral bodies.
Rough inner portion of the vertebral bodies.
Also, ALL, PLL, radiate ligament of head of rib, intra-articular lig.
What are the functions of the IVD?
Absorbs forces.
Shape contributes to L & C curves (lordotic)
Binds and limits motion at one segment.
Resists forces - shear, compression, torsion.
What is the innervation of the anulus fibrosus?
N: Branches of ventral primary rami
What is the blood supply for the anulus fibrosus?
BS: Spinal branches, sparsely. Drained by internal and external vertebral plexuses.
What is the innervation for the nucleus pulposus?
Lacks direct innervation (cannot feel pain in this region)
What is the blood supply for the nucleus pulposus?
Lacks direct blood supply.
Describe disc degeneration as a pathology of IVDs.
Small tears in the anulus fibrosus.
Over time, all discs degenerate. Can be sped up, making it pathological.
Causes: trauma, genetics, repetitive stress.
Common at L5-S1
Describe disc herniation as a pathology of IVDs.
Nucleus pulposus herniates from within the anulus fibrosis, reaching the periphery. Usually occurs posterolaterally, due to reinforcement by PLL.
Also known as “slipped disc”
Describe disc protrusion as a pathology of IVDs.
Nucleus pulposus protrudes from within the anulus fibrosis, but the anulus fibrosis is still intact. Can compress the spinal nerves. Usually occurs posterolaterally, due to reinforcement by PLL.
Also known as “bulging disc”
Describe the symptoms of a herniation of C6-C7.
Sensory and motor deficits
- abnormal sensations
- loss of voluntary movement
Sometimes asymptomatic.
Describe Schmorl’s nodes as a pathology of IVDs.
Pockets of nucleus pulposus that were forced into the vertebral body by the VEP. Usually incidental in finding, show up as dark, round spots in vertebral bodies in X-rays.
Unsure if they are linked to pain.
Define paresis.
Slight/incomplete loss of voluntary muscle movement.
Not strictly neurological.
Define paralysis.
Complete loss of voluntary muscle movement
Define paresthesia .
Abnormal sensations in the body, resulting from some neuropathy.
What are the 3 Ps of neuropathy?
Paresis, paralysis, and paresthesia.
