Msk Investigations Flashcards
First line investigation when suspecting SLE
Urinalysis to test for renal failure
Investigation for Giant Cell Arteritis
(Include 1st line)
1st line: ultrasound
Confirm with temporal artery biopsy (although not always positive)
Anti ro/ anti la indicates?
sjorgens (60-70%)
1st line investigation for cauda equina symptoms (bilateral scaitic radoculopathy + incontenince)
Urgent MRI + pr exam
Pagets
(Ix and what it should show)
X ray- initial: well define lucency, mishapen bone
- sclerotic phase: enlarged bone, inc cortex density, coarse trabecular pattern
Isotope bone scan- shows distribution
Biochem: inc alkaline phosphatase
skull x ray showsthickened calvarium and ill defined sclerotic lucent areas throughout
septic arthritis investigations
Hot swollen acutely painful joint- assume septic arthritis til proven otherwise.
1st line: aspirate joint for microscopy, culture & sensitivity and bloods- inc CRP, blood culture if pyrexial
x ray/MRI
Gout
(most appropriate investigation?)
most appropriate: joint aspiration and CRP on admission and
to confirm diagnosis: serum urate after 2 weeks
Rheumatoid arthritis investigations
what to use if in diagnostic doubt?/ what is the gold standard test for RA
Clinical diagnosis
bloods: raised inflammatory markers
rheumatoid factor, anti CCP (more specific)
X-ray hands and feet of all suspected RA patients
MRI is gold standard!!, only use if in diagnostic doubt
sjorgens investigations
schirmers test- occular dryness
bloods:
-positive anti-Ro & anti La
-possible inc in IgG & plasma viscosity/ESR
- lymph
osteomyelitis investigation
MRI
Ixs for ankyosing spndylitis
what test is used if in diagnostic doubt
-( Spondyloarthritis cannot be reliably diagnosed or ruled out by a single test)
1st: X ray; (sacroillitis: subchondral erosions, sclerosis, squaring of lumbar vertebrae, bamboo psine etc.)
if X ray doesnt show anything but suspicion remains high do MRI
other tests:
HLA B27 gene- test for if 3 of criteria have been met
What confirms diagnosis of a metatarsal fracture
MRI or bone scan to confirm diagnosis
Xray wont show fracture for 3 weeks (until resorption at the fracture ends occurs or callus begins to appear)
Extension of the big toe indicates what nerve is working?
Deep peroneal
Who should be referred for dexa
Patients >50y with low trauma fracture “stop at one”
Patients at inc risk via risk assessment tools eg. Frax or qfactor >10% risk of fracture over 10years
Diagnostic test for ankylosing spondylitis
MRI of sacroilliac joints
Lateral to medial layout of femoral triangke
Femoral nerve, fem. Artery. Fem vein. Lymphatics.
NAV
Serious trauma from a car accident or fall from high place, what type of bone fracture
Comminuted fracture
Fall on an iutstretched arm associated with what type of fracture
More common in kids because…
Greenstick
(Partial fracture)
Kids bones are softer
positive phalens test indicates…
carpal tunnel syndrome
aspirate of synovial fluid in gout shows?
what are you testing when you aspirate
-microscopy- needle shaped, negatively befringeent monosodium urate crystals (confirms diagnosis)
- gram stain/culture to rule out septic arthritis
how to diagnose SLE
(ANA very specific for SLE)
SLE criteria 4 or more (at least 1 lab and 1 clinical) or biopsy proven lupus nephritis + antidsdna/anti sm
diagnostic test for osteoporosis
DEXA score of <-2.5
occult hip fracture Ix (not able to see on x ray)
MRI
gold standard test for rib fracture
CT
diagnostic test for polymyositosis/dermosyotsis
muscle biopsy: shows perivascular inflammation and muscle necrosis
what are the criteria to diagnose kawasaki disease
4/5 of these symptoms
CRASH & Burn
Conjunctivitis
Rash
Adenopathy (lympadenopathy)
Strawberry tongue
Hands/feet (peeling of hands/feet)
burn: fever for 5/more days
criterion to diagnose atypical kawasaki disease
2/3 of the CRASH and burn symptoms
and
CRP> 3mg/dl
ESR>40mm/hr
>3 supplemental labs (eg albumin) OR abnormal echocardoigram
what do you have to screen for in kawasaki disease? and what tool do you use
echo to check for coronary artery aneurysms
initial imagiing of choice for suspected achilles tendon rupture
ultrasound
what is the result for schobers test in someone with ankylosing spondylitis and what does it indicate
<5cm
redcuded lumbar flexion
vertebral tb (aka potts disease) ix
x ray and MRI
gold standard test for any joint pathology
MRI
what does the DAS 28 score take into account
Sore joint count,
swollen joint count,
ESR
global health score.
Ix for SUFE and confirm diagnosis
X-ray AP and frog leg view on BOTH hips
confirm diagnosis and graded by klein line (how much is intersecting the femoral head)
suspected psoas absecess investigation
CT abdomen
polymyalgia rhuematica Ix findings
inc ESR and CRP
if there is osteoporosis in a man what should you check
testosterone
first line investigation for suspected osteoporotic vertebral fracture
X-ray spine
scaphoid fracture ix
(2)
1st line: two oblique, AP (anterior posterior) and lateral x-ray view
definitive: MRI
can you age a bruise for non accidental injury
no
can age diff fractures tho
septic arthritis vs rheumatoid arthritis joint aspirate findings
septic: cloudy/opaque, yellow , >90% leukocytes, usually g+ (s.A)
RA: clear, viscuos, predominantly polymorphonuclear neutrophils
what are the ottowa rules
when to x ray for ankle fracture:
if there is pain in malleoulur area and any one of the criteria below then an ankle x-ray series is indictaed
-bony tenderness at posterior edge/tip of lateral malleoulus
- bone tenderness at the posterior edge/tip of the medial malleoulus
- inability to bear weight for 4 steps both immediatley after the injury and when examining
what does a positive simmonds test indicate
calcaneal tendon (achilles tendon) rupture
what is more reliable lachman or anterior drawer test
lachman
cauda equina Ixs
PR exam and urgent MRI
1st line imaging Ix for ACL rupture
MRI
acetabulum fracture imaging
CT
shoulder dislocation Ix
X:ray two planes> AP erect and lateral
first line Ix for rotator cuff tear
and gold standard
1st line: ultrasound
G.S: MRI
