fibrous, cartilaginous, synovial
What are the structural classifications for joints?
Synarthroses
-immovable; common in axial skeleton
amphiarthroses
-slightly movable; common in axial skeleton
c
Which joints are common in axial skeleton?
a. synarthroses
b. amphiarthroses
c. a & b
d. diarthroses
a
Which joints are common in appendicular skeleton?
a. diarthroses
b. fibrous
c. cartilaginous
d. amphiarthroses
Diarthroses
-freely movable; common in appendicular skeleton
Suture
-this type of joint is held together with very short, interconnecting fibers, and bone edges interlock
skull
Sutures are only found where?
syndesmosis
-joint held together by a ligament.
-fibrous tissue is longer than that of sutures
Gomphosis
-peg-in-socket fibrous joint.
in teeth
Where are gomphosis joints located?
suture, syndesmosis, gomphosis
What are your fibrous joints?
synchondroses, symphyses
What are your cartilaginous joints?
syncondroses
-bones united by hyaline cartilage
Symphyses
-bones united by fibrocartilage
synovial joint
-most movable type of joint
-ends of opposing bones are covered with hyaline cartilage to absorb compression
-joint cavity
fibrous capsule
-outer layer; dense irregular CT that strengthens joint
synovial membrane
-inner layer; loose CT that lines joint capsule covering internal joint surfaces and makes synovial fluid
synovial fluid
-viscous glycoprotein filtrate of blood produced by fibroblasts to lubricate joints
innervated, well vascularized
What are some unique characteristics to synovial joints?
fill in gaps to improve fit, distribute weight evenly, minimize wear and damage
What is the function of articular discs?
lubricating devices
-allows joining bones to move across on another with minimal friction
weeping lubrication
-fluid is squeezed out as opposing cartilages touch
-cartilages ride on the slippery film; not each other
-when pressure ceases, fluid rushes back in (sponge) and ready for next load
HLA-DRB1
-is an MHC cell surface receptor
-ligand for T-cell receptor is upregulated in infection
-T-helper cells release TNF and ILs
Rheumatoid factor (RF)
-autoantibody precipitates when the blood cools; Binds with IgG to form complex to contribute to disease
Pannus
-destructive vascular granulation tissue caused by inflammation
MMP-1
-destroys collagen I
NSAID, DMARDs, corticosteroids
Treatment options for rheumatoid arthritis?
Hydroxychloroquine
stabilizes lysosomes
Methotrexate
-interferes with purine metabolism to reduce inflammation
adalimumab, infliximab, etanercept
-scavenges circulating/local TNF
e
Which joint diseases have an unknown etiology (cause)?
a. psoriatic arthritis
b. osteoarthritis
c. gout
d. rheumatoid arthritis
e. a & d
HLA-B27
What is the cell surface receptor that is associated with psoriatic arthritis?
primary variant cause of osteoarthritis
-intrinsic defects in articular cartilage from wear and tear
secondary variants
-congenital defects, trauma, infection, crystal deposits, metabolic disorders, inflammatory diseases
osteoarthritis
which joint disease can result in bony outgrowths (osteophytes, nodes, and bunions?
Hyperuriccemia
-elevated uric acid levels that crystalize in joints in the form of monosodium rate to form deposits
Colchicine
-microtubule polymerization inhibitor; inhibits leukocyte migration and phagocytosis
Allopurinol
-inhibits xanthine oxidase preventing uric acid formation