Term
Where is synovial tissue found? Not found? |
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Definition
Lining fibrous joint capsule, covers tendons & ligaments. Not on articular surfaces or menisci. |
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Term
What cell type coats the surface of synovial tissue? |
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Definition
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Term
What are the 2 types of synoviocytes & how do they differ? |
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Definition
Type 1 (A): Phagocytic cells, therefore ↑ lysosomes/vacuoles
Type 2 (B): Synthesizing cells (make hyaluronate), therefore ↑ RER |
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Term
Main component of synovial fluid? |
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Definition
Glycosaminoglycans, specifically hyaluronic acid |
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Term
Physical characteristics of normal synovial fluid? |
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Definition
Clear, highly viscous (like egg whites) |
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Term
Function of synovial fluid? |
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Definition
Lubricate articular cartilage & provide nourishment via diffusion |
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Term
3 types of joint lubrication? + describe |
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Definition
1)Boundary - molecular film very thin, 2)Weeping - pressure to cartilage causes fluid to weep out, 3) Boosted - fluid in peaks & valleys |
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Term
Characteristics of Inflammatory synovial fluid? |
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Definition
Increased vloume, low viscosity, cloudy yellow, increased WBCs/PMNs |
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Term
What type of synovial fluid would be found w crystal synovitis or RA? |
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Definition
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Term
Characteristics of SEPTIC synovial fluid? |
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Definition
Increased volume, mixed viscosity, opaque, increased WBCs/PMNs, Gram + |
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Term
What type of joint is synovial? |
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Definition
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Term
2 layers of joint capsule in synovial joints? |
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Definition
Outer=fibrous layer, Inner=highly vascular synovial membrane |
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Term
Function of menisci in joints? |
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Definition
Fibrocartilagenous washer, aids in rotation stability. |
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Term
In which 3 joints would you find menisci? |
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Definition
Knee, radiocarpal joint, sternoclavicular. |
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Term
What does the Mucin Clot test test for and how? |
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Definition
Addition of acetic acid to normal joint fluid should cause all the hyaluronic acid (mucopolysaccharide) to clump into a mucin clot. In RA damage to the synovial cells causes decreased hyaluronate production & there is either no mucin clot or it just falls apart, making the lqd look cloudy. |
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Term
What mucopolysaccharide is found in the synovial fluid around joints & in the vitreous humor of eyes? |
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Definition
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Term
What is hyperuricemia and why does it occur? |
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Definition
High concentration of uric acid in the blood due to overproduction or underexcretion. |
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Term
Which is more common, the overproduction or underexcretion of uric acid? |
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Definition
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Term
3 causes of uric acid overproduction? |
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Definition
1)Ethanol, 2)Genetics, 3)Myeloproliferative disorders (ie psoriasis) |
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Term
How can renal insufficiency contribute to gout? |
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Definition
Underexcretion of uric acid. |
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Term
4 drugs that can lead to underexcretion of uric acid? |
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Definition
Diuretics (CHF), low dose Aspirin, Heparin, Cyclosporine (transplant pts) |
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Term
When are women more susceptible to gout & why? |
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Definition
After menopause, estrogen has a uricosuric effect. |
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Term
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Definition
1)Asymptomatic Hyperuricemia, 2)Acute Gout, 3)Intercritical Gout, 4)Chronic Tophaceous Gout |
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Term
What causes pain in Acute Gout? |
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Definition
Precipitating uric acid crystals are being phagocytosed by WBCs causing an inflammatory cascade. |
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Term
During what phase is a good time to initiate uric acid lowering therapy? |
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Definition
Intercritical (eye of the storm) |
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Term
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Definition
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Term
What do gout crystals look like under the microscope? |
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Definition
Negatively bifringent (yellow when parallel to polarizing light), needle shaped, intracellular. |
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Term
What do pseudogout crystals look like under the microscope? |
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Definition
Positively bifringent (blue when parallel to polarizing light), rhomboid shaped |
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Term
What are pseudogout crystals made of? |
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Definition
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Term
How does Chronic Tophaceous Gout present? |
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Definition
Polyarticular synovitis & Tophi on joints. |
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Term
What are the 4 most common sites to be affected by gout? |
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Definition
Big toe, heel, ankle, instep |
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Term
What attributes of septic arthritis aspirate differentiate it from that of gout? |
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Definition
Low glucose (vs normal), extra-cellular crystals |
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Term
What would aspirate of a tophus look like under microscope? |
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Definition
Gout crystals but no cells |
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Term
What is the most important disease to r/o when diagnosing gout & why? |
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Definition
Septic arthritis, can cause irreversible destruction of cartilage in 2 days |
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Term
What bacteria is most likely to grow in synovial fluid w extracellular crystals & WBC >80,000? |
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Definition
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Term
What is contraindicated in acute gout? |
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Definition
Uric acid lowering agents |
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Term
Treatment choices for acute gout? |
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Definition
NSAIDs, Colchicine, Intraarticular Steroids, Systemic Steroids |
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Term
How does colchicine prophylaxis prevent gout attacks? |
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Definition
Keeps tubules from forming --> stops macrophages from dividing |
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Term
What are 4 situations that would indicate initiation of Uric Acid lowering therapy? |
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Definition
1)Recurrent attacks (despite colchicine), 2)Uric acid stones (could be in kidney), 3)Tophi (could also be in kidney), 4)Prior to chemo (which lyses a ton o cells) |
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Term
Who would benefit from a Uricosuric agent? |
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Definition
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Term
Which uric acid lowering therapy is indicated for an overproducer? |
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Definition
Xanthine Oxidase Inhibitor |
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Term
Is hypercalcemia a risk factor for pseudogout? |
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Definition
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Term
9 risk factors for pseudogout? |
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Definition
Hyperparathyroidism, hypothyroidism, diabetes, advanced age, acute illness, Wilson's disease, hemochromatosis, ochronosis, osteoarthritis |
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Term
4 most common sites for pseudogout? |
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Definition
knee, ankle, wrist, shoulder |
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Term
Risk factors for Milwaukee Shoulder? |
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Definition
Old lady w severe chronic synovitis, Overuse & osteoarthritis in dominant arm, Rotator cuff tear |
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Term
What is Milwaulkee Shoulder (pathogenesis)? |
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Definition
Rapidly progressive destructive arthritis due to Calcium Hydroxy Apatite deposition, CHA crystals are phagocytosed --> inflammatory cascade |
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Term
How does the CHA that causes Milwaukee Shoulder get into the joint fluid in the first place? |
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Definition
Overuse & wear n tear shears it off bone |
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Term
What is the method of diagnosis for Milwaukee Shoulder? |
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Definition
CHA crystals on Electron Microscope |
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Term
Treatment for Milwaukee Shoulder? |
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Definition
NSAIDs, colchicine, aspiration, intra-articular steroids, rehab |
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Term
What is the only true "cure" for Milkwaukee Shoulder? |
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Definition
Rotator cuff repair &/or complete shoulder replacement |
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