approach to articular / MSK disorders Flashcards
important factors to consider in primary complaint
- articular or nonarticular
- inflammatory or noninflammatory
- acute or chronic
- localized (monoarticular) or widespread (polyarticular)
physical exam signs that pain is articular
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
signs of inflammation
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)
quick differential for acute articular complaint
- acute arthritis: infectious arthritis, gout, pseudogout, reactive arthritis
- initial presentation of chronic arthritis
quick differential for acute nonarticular complaint
trauma/fracture, fibromyalgia, polymyalgia rheumatica, bursitis, tendinitis
types of inflammatory disorders
infectious (gonorrhea, tb), crystal-induced, immune-related (RA, SLE), reactive (rheumatic fever, reactive arthritis), or idiopathic
morning stiffness
related to inflammatory condition
- precipitated by prolonged rest
- severe
- lasts for hours
- may improve with activity or anti-inflammatory agents
important things to elicit from clinical history
onset (abrupt, indolent)
evolution (chronic, intermittent, migratory, additive)
duration
distribution (mono,, oligo, poly)
precipitating events (trauma, drugs, recent illness)
DM can lead to?
carpal tunnel syndrome
renal insufficiency can lead to?
gout
rheumatic review of systems
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
red flag diagnoses
septic arthritis, gout, or fracture
DIP pain differential
OAA, psoriatic, reactive
PIP pain differential
OA, SLE, RA, psoriatic
MCP pain differential
RA, pseudogout, hemochromatosis
1st CMC pain differential
OA
wrist pain differential
RA, pseudogout, gonococcal arthritis, juvenile arthritis, carpal tunnel syndrome
Heberden’s
DIP
Bouchard’s
PIP
labs to look for evidence of inflammation
CBC w/ diff, ESR, CRP
examples of diseases that cause extreme elevation of ESR/CRP
sepsis, pleuropericarditis, polymyalgia rheumatica, giant cell arteritis, adult Still’s disease
utility of measuring serum uric acid level
- 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)
what can cause an increase in uric acid?
inborn errors of metabolism (Lesch-Nyhan syndrome)
disease states (renal insufficiency, myeloproliferative disease, psoriasis)
drugs (alcohol, cytotoxic therapy, thiazides)
drugs that can induce lupus
hydralazine, procainamide, quiniide, tetracyclines, tumor necrosis factor inhibitors
sensitivity / specificity of RF
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
specificity / sensitivity of ANA
found in 5% of adults, 14% of elderly / chronically sick people
very sensitivity, but poorly specific for lupus
when to consider synovial fluid aspiration
- monoarthritis (acute or chronic)
- trauma with joint effusion
- monoarthritis in a pt w/ chronic polyarthritis
- suspicion of joint infection, crystal-induced arthritis, hemarthrosis
how to analyze synovial fluid
- appearance, viscosity
- WBC count, differential
- gram stain, culture and sensitivity
- crystal identification by polarized microscopy
what to consider if effusion is hemorrhagic
trauma or mechanical derangement
coagulopathy
neuropathic arthropathy
characteristics of noninflammatory synovial fluid
clear, viscous, amber-colored
WBC
characteristics of inflammatory synovial fluid
turbid, yellow
WBC 2,000-5,000, PMN predominance
eg: RA, gout
characteristics of septic synovial fluid
opaque, purulent
WBC >50,000, w/ >75% PMNs
difference in gout and pseudogout crystals
monosodium urate crystals: long, needle-shaped, negatively birefringent, usually intracellular
calcium pyrophosphate dihydrate crystals: short, rhomboid-shaped, positively birefringent
examples of use of U/S
synovial cysts, rotator cuff tears, tendon injury
examples of use of CT
herniated intervertebral disk, sacroiliitis, spinal stenosis, spinal trauma, osteoid osteoma, stress fracture
examples of use of MRI
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
