Joint Pathology Flashcards
bony congruence allows?
even distribution of pressure
3 layers of articular cartilage
superficial: parallel fibers
middle: random fibers
deep: perpendicular fiberes
what do GAGs do in articular cartilage?
draws in water
what does collagen and chondrocytes and GAGs do in articular cartilage?
water drawn in by GAGs, held together by collagen II, and maintained by chondrocytes
blood vessels in aritcular cartilage?
Nope
capsule, tendons, ligaments purpose?
stability and movement
synovial fluid contains?
- plasma filtrate
- extra slippery hyaluronic acid
2 cells in synovium ?
Type A: macrophage-like
Type B: fibroblast-like (make hyaluronic acid)
OA presentation?
- Chronic, few joint
- weight bearing or prev. injured
- worse with use
RA presentation?
- inflamm, systemic
- symmetrical, small joints
- morning stiffness
- better with use
Gout presentation?
- paroxysmal acute inflammation
2. uric acid crystallisation
what is gout in big toe called?
Podagra
Damage precipitates what 3 things in OA?
- chondrocyte proliferation
- cytokine release
- matrix depletion
matrix depletion or unravelling releases what things?
enzymes (collagenases, MMPs)
what bony changes in OA?
thickening and microfractures,
what is shedding of cartilage called?
fibrillation “shredded appearance”
bone on bone causes 3 things:
- eburnation
- cysts
- osteophytes
3 big things in morphology of OA?
- non-uniform less of cartilage
- subchondral thickening
- osteophytes
signs of OA: 3
- reduced ROM
- crepitus
- osteophytes
onset of OA?
insidious
pain type in OA?
deep achey
worse after use
Heberden’s Nodes?
DIP
Bouchard Nodes?
PIP
X-rays dx OA?
Nope, little correlation
5 OA risk factors:
- age
- obesity
- prev. injury
- heavy use of joint
- genetic
OA not common in which joint?
shoulder
elbow
RA affects not just joint but:
skin
blood vessels
heart
lungs
RA pathogenesis which t-helper cells?
Th1, Th17
RA pathogenesis which cytokines releases? 4:
IL-1,6,17
TNF-a
RA pathogenesis T-cells activate what 4 things?
fibroblasts
macros
osteoclasts
B-cells
RA pathogenesis what is formed in joint?
granulation tissues-like pannus due to breakdown of cartilage and bone
what happens in synovium of RA pathogenesis ?
- germinal centres
- mononuclear infiltrate
- hyperplasia with villus formation = pannus
what does pannus lead to eventually in RA pathogenesis ?
fibrosis and bony union of joints
signs of RA?
- warm swollen joints
2. rheumatoid nodules
symptoms of RA?
- morning stiffness - eases with activity
2. symmetric polyarthritis -starts at hands then feet
what is a rheumatoid nodule?
granulomatous inflammation
with central necrosis
how is joint space loss in RA?
uniform loss
Risk factors for RA? 4 things:
- genetic
- women
- age: 25-55
- smoking
When do you get systemic gout?
after 20-30 years of increasing uric acid levels, then precipitates into crystals
uric acid crystals like to precipitate where?
in cool areas with low pH and nucleating agents: eg. big toe
uric acid crystals do what do cause pain?
activate inflammation,
synovial cells
complement
neutrophil lysis
what are tophi?
uric acid crystal deposition in soft tissue: articular cartilage and capsule
gout and kidneys?
kidney stones
gouty nephropathy
what is a gouty tophi?
granulomatous inflammation (foreign type body)
gold standard for gout test?
joint aspiration: crystals
serum urate in gout?
not reliable
x-ray findings for gout?
- punched out erosions
2. overhanging edges
gout risk factors: 4
- male
- uric acid metabolism
- genetics
- metabolic syndrome
high uric acid is related to what things that would help upright human evolutionarily:
- Na+ retention
- hypertension
- insulin resistance
