approach to articular / MSK disorders

Question 1

important factors to consider in primary complaint

Answer 1

1. articular or nonarticular
2. inflammatory or noninflammatory
3. acute or chronic
4. localized (monoarticular) or widespread (polyarticular)

Question 2

physical exam signs that pain is articular

Answer 2

deep or diffuse pain, pain or limited ROM on active and passive movement, swelling (caused by synovial proliferation, effusion, or bony enlargement), crepitation, instability, ‘locking’ or deformity

Question 3

signs of inflammation

Answer 3

4 cardinal signs (erythema, warmth, pain or swelling)
systemic symptoms (fatigure, fever, rash, weight loss)
labs (ESR, CRP, thrombocytosis, anemia of chroni disease, or hypoalbuminemia)

Question 4

quick differential for acute articular complaint

Answer 4

• acute arthritis: infectious arthritis, gout, pseudogout, reactive arthritis
• initial presentation of chronic arthritis

Question 5

quick differential for acute nonarticular complaint

Answer 5

trauma/fracture, fibromyalgia, polymyalgia rheumatica, bursitis, tendinitis

Question 6

types of inflammatory disorders

Answer 6

infectious (gonorrhea, tb), crystal-induced, immune-related (RA, SLE), reactive (rheumatic fever, reactive arthritis), or idiopathic

Question 7

morning stiffness

Answer 7

related to inflammatory condition

• precipitated by prolonged rest
• severe
• lasts for hours
• may improve with activity or anti-inflammatory agents

Question 8

important things to elicit from clinical history

Answer 8

onset (abrupt, indolent)
evolution (chronic, intermittent, migratory, additive)
duration
distribution (mono,, oligo, poly)
precipitating events (trauma, drugs, recent illness)

Question 9

DM can lead to?

Answer 9

carpal tunnel syndrome

Question 10

renal insufficiency can lead to?

Answer 10

gout

Question 11

rheumatic review of systems

Answer 11

fever, chills, sweats, weight loss, fatigue anorexia
recent URI/GI illness, urethritis/dysuria
alopecia, rash, photosensitivity
eye pain or redness, visual changes
hearing loss
nasal discharge, sinus tenderness
sicca symptoms
oral or genital ulcers
raynouds
headache, jaw claudication, scalp tenderness
dyspnea, cough, hemoptysis, pleuritic or other chest pain
dysphagia, naausea, emesis, GERD, abdominal pain, change in bowel habits
testicular pain
joint pain, myalgias, morning stiffness
back pain, night pain, morning stiffness
extremity weakness or numbness
epistaxis or other bleeeding
seizures or psychosis
miscarriages

Question 12

red flag diagnoses

Answer 12

septic arthritis, gout, or fracture

Question 13

DIP pain differential

Answer 13

OAA, psoriatic, reactive

Question 14

PIP pain differential

Answer 14

OA, SLE, RA, psoriatic

Question 15

MCP pain differential

Answer 15

RA, pseudogout, hemochromatosis

Question 16

1st CMC pain differential

Answer 16

OA

Question 17

wrist pain differential

Answer 17

RA, pseudogout, gonococcal arthritis, juvenile arthritis, carpal tunnel syndrome

Question 18

Heberden’s

Answer 18

DIP

Question 19

Bouchard’s

Answer 19

PIP

Question 20

labs to look for evidence of inflammation

Answer 20

CBC w/ diff, ESR, CRP

Question 21

examples of diseases that cause extreme elevation of ESR/CRP

Answer 21

sepsis, pleuropericarditis, polymyalgia rheumatica, giant cell arteritis, adult Still’s disease

Question 22

utility of measuring serum uric acid level

Answer 22

• diagnosis of gout, monitoring response to urate-lowering therapy
• hyperuricemia is associated w/ increased incidence of gout and nephrolithiasis, but levels may not correlate with severity of disease
• 5% have nl levels in acute gouty attach (presumably from acute inflammation augmented excretion of uric acid)

Question 23

what can cause an increase in uric acid?

Answer 23

inborn errors of metabolism (Lesch-Nyhan syndrome)
disease states (renal insufficiency, myeloproliferative disease, psoriasis)
drugs (alcohol, cytotoxic therapy, thiazides)

Question 24

drugs that can induce lupus

Answer 24

hydralazine, procainamide, quiniide, tetracyclines, tumor necrosis factor inhibitors

Question 25

sensitivity / specificity of RF

Answer 25

note IgM RF = autoantibodies against Fc portion of IgG found in 80% of pts with RA and seen in low titers in chronic infections 4-5% of a healthy population will test positive

Question 26

specificity / sensitivity of ANA

Answer 26

found in 5% of adults, 14% of elderly / chronically sick people very sensitivity, but poorly specific for lupus

Question 27

when to consider synovial fluid aspiration

Answer 27

1. monoarthritis (acute or chronic) 2. trauma with joint effusion 3. monoarthritis in a pt w/ chronic polyarthritis 4. suspicion of joint infection, crystal-induced arthritis, hemarthrosis

Question 28

how to analyze synovial fluid

Answer 28

1. appearance, viscosity 2. WBC count, differential 3. gram stain, culture and sensitivity 4. crystal identification by polarized microscopy

Question 29

what to consider if effusion is hemorrhagic

Answer 29

trauma or mechanical derangement coagulopathy neuropathic arthropathy

Question 30

characteristics of noninflammatory synovial fluid

Answer 30

clear, viscous, amber-colored | WBC

Question 31

characteristics of inflammatory synovial fluid

Answer 31

turbid, yellow WBC 2,000-5,000, PMN predominance eg: RA, gout

Question 32

characteristics of septic synovial fluid

Answer 32

opaque, purulent | WBC >50,000, w/ >75% PMNs

Question 33

difference in gout and pseudogout crystals

Answer 33

monosodium urate crystals: long, needle-shaped, negatively birefringent, usually intracellular calcium pyrophosphate dihydrate crystals: short, rhomboid-shaped, positively birefringent

Question 34

examples of use of U/S

Answer 34

synovial cysts, rotator cuff tears, tendon injury

Question 35

examples of use of CT

Answer 35

herniated intervertebral disk, sacroiliitis, spinal stenosis, spinal trauma, osteoid osteoma, stress fracture

Question 36

examples of use of MRI

Answer 36

avascular necrosis, osteomyelitis, intraarticular derangement and soft tissue injury, derangements of axial skeleton and spinal cord, herniated intervertebral disk, pigmented villonodular synovitis, inflammatory and metabolic muscle pathology