MSK Flashcards
What does investigations of osteoporosis involve?
assess/estimate risk of fragility fractures
DEXA scans
When would you assess risk of fragility #?
women >65yr, males >75yrs
OR
women <65yrs, males <75yrs with the presence RFs - previous
What two ways are there to assess risk of Fragility #
FRAX score - 10yr risk assessment, in 40-90yrs, assess risk factors, can account BMD (better estimate if included)
Qfracture - 10yr risk assessment, in 30-99yrs, assess a larger group of RFs
FRAX score interpretation (w/o BMD) & relevant mx?
low risk = reassure, lifestyle advice, reassess in ~5yrs depending on context
intermediate risk = measure BMD and recalculate risk - check to see above/below intervention threshold
high risk = consider tx without BMD measurement. sometimes BMD appropriate such as in younger postmenopausal women
Indications for a DEXA scan?
- high fragility fracture risk (FRAX score or QFracture)
- 50yrs+ with hx of fragility fracture
- <40yrs + major risk of fragility fracture
(may need fracture liaison service referral)
interpret DEXA scan results
0 = normal bone density
0+ = good bone density
-2.5 - 0 = osteopenia (mild weakening)
< -2.5 = osteoporosis
VItamin D levels request indications?
osteomalacia (or rickets)
fragility fractures
Interpret vitD levels in fragility fractures context?
<30 = deficieint - high dose repalcement
30-50 = insufficient = medium/maintenance dose
> 50 = sufficient = no tx indication at this point
What is arthroscopy?
Indications?
surgical procedure - often as keyhole surgery
= thin telescope with light source allowing inside of the joint to be visualised
indications = diagnostic and surgical/therapeutic procedures
- mainly used in the investiagtion/treatment of knee problem - Meniscal/Cruciate injuries
Complications with arthroscopy?
accidental damage to joint and surrounding structures
excessive bleeding into joint
infection
Indications of joint aspiration?
What is analysed in aspirate for each indication
- septic joint
- cloudy/purulent appearance
- gram stain
- WCC
- culture
- crystal analysis - Gout
- crystal analysis
(- culture to r/o septic joint)
- neg birefringent crystals - Pseudogout
- crystal analysis
(- culture to r/o septic joint)
- positive birefringent crystals
What other Ix are done in septic joint/gout presentations?
Imaging/XR knee
- septic joint = effusions
- gout = eccentric erosions, punched out lesions, soft tissue trophi
- pseudogout = chondrocalcinosis = linear calcifications
What are the Investigations done in acute compartment syndrome?
intracompartmental pressure measurements
What assessment criteria is used in Cauda Equina?
ASIA
american spinal injury assessment
What is the main Ix of choice in suspected Cauda Equina
Urgent MRI
What scoring system is used in cervical spine fractures?
what does it account?
Canadian C-spine rule
age >65, extremity parasthesia or dangerous mechanism of injury
low risk factors
able to rotate neck 45° left and right
low risk = r/o fracture w/o imaging
high risk = XR spine
Indication for imaging in C-spine fractures?
intoxicated at time of injury/presentation
altered GCS
neck pain/tenderness
distracting injury present
What other Ix can be done in C-spine fractures?
XR, CT and MRI
what investigations are done in joint dislocation?
XR (not ankle)
CT (+/- angio - if associated vascular injury)
MRI - evaluate soft tissue injury
open fracture assessment tools include?
Gustilo anderson classification - size of wound/soft tissue injury
BOAST 4 guidelines
- initial assessment and management
- fracture in long bone, hind foot or midfoot
Investigations for open fractures?
Bloods
XR
CT (with/out angio depends on any associated vascular damage)
Investigations for a NOF?
Bloods - FBC, U&E, LFTs, TFTs, VitD, Folate/B12, clotting
XR = Shenton line disruption
- if normal consider MRI
MRI not available within 24hrs= do CT
What investigation is done in distal radius fractures?
XR - AP and lateral
What XR should be done on scaphoid fracture?
what if XR is normal?
AP, lateral and scaphoid views (Ulnar deviation + 45° pronation)
if XR NAD = repeat in 10-14days (immbolise wrist)
CT/MRI can be done for occult fractures
Investigations of forearm fractures?
Full length XR - AP and lateral
elbow and wrist joint imaged too
What is used to determine XR in ankle?
Ottowa ankle rules
- bony tenderness in lateral malleolus
- bony tenderness in medial malleolua
- point tenderness on base of 5th Metarsal
- point tenderness on navicular bone
- inability to weight bear (<4steps)
What forms of imaging are done in Ankle fractures?
XR - AP, Mortise & lateral views
(mortise = 15-20° internal rotation)
CT scan - complex fractures
MRI - occult # or ligamentous injury suspected
Ix in Quadriceps tendon rupture
often times a clinical diagnosis
XR = r/o other causes
USS = confirmation of diagnosis
MRI = nature and extent of rupture
Investigations in achilles tendon rupture?
usually a clinical diagnosis
XR - rule out other causes
USS = confirm diagnosis
MRI - nature and extent of rupture
What investigations are done in suspected Ankylosing Spondylitis?
ESR/CRP - usually raised
XR
- sacroillitis = sclerosis & subchondral erosions
- syndesmophytes
- ossification of ligaments, discs, joints
- fusion of facet, sacroiliac and costovertebral
- ‘bamboo spine’ - sqauring of lumbar vertebrae
IF XR NAD but suspicion remains high - MRI may reveal early inflammation involving sacroilliac joints
Genetic testing for HLA-B27
CXR - apical fibrosis
Spirometry - may revela a restrictive picture
What investigations are done in suspected Herniated Nucleus Pulposus/herniated disc?
MRI is usually diagnostic
What investigations are done in suspected spinal stenosis?
MRI
Exclusion of PAD
- ABPI and CT angio - r/o intermittent claudication
What investigations are done in suspected Chrondomalacia patella/patellofemoral pain syndrome?
XR knee = skyline view
- bone on bone patella and femur
What investigations are done in suspected Meniscial Injury?
XR - if ottowa rules warrant
MRI scan - first line imaging to establish diagnosis
Arthroscopy - gold standard for meniscial tear
What investigations are done in suspected cruiciate injury?
MRI scan first line imaging
arthroscopy - gold standard for diagnosing a cruciate ligament tear
What investigations are done in suspected osgood-schlatter disease?
usually a clinical diagnosis
What investigations are done in suspected patella bursitis?
bursal aspirate - to rule out septic/crystal-induced bursitis
XR - in suspected bony pathology
Blood tests = CRP/ESR, ECC, uric acid, glucose, ANA Ab and RF
What investigations are done in suspected SCFE?
XR
- AP
- bilateral hip and frog leg lateral views
What investigations are done in suspected Legg perthes disease?
AP hip XR and frog leg lateral views
- widening of joint space
decreased femoral head size/flattening
What investigations are done in suspected developmental hip dysplasia?
USS - used to confirm a diagnosis if clincally suspected
> 4.5months - XR
What investigations are done in suspected trochanteric bursitis?
usually a clinical diagnsis
What investigations are done in suspected Dislocated hip?
XR
What investigations are done in suspected AVN of Hip?
XR
- initally normal
- osteopenia and presence of microfractures
- crescent sign
MRI scans
- >6wks of symptoms with normal XRs
What investigations are done in suspected NOF?
XR
- AP and lateral
- shentons line disrupted
MRI/CT is XR normal but clinical suspicion
What investigations are done in suspected septic arthritis?
Joint aspirate - gram stain and culture
What investigations are done in suspected acute osteomyelitis
Bloods - raised WCC, CRP/ESR
XR = osteopenia & bone destruction
MRI - >sensitivity
Blood cultures - +ve causative organisms
Bone cultures - establish organism and Abx sensitivity
What investigations are done in suspected Osteoarthritis?
XR changes
- loss of joint space
- osteophytes
- subchondral sclerosis
What investigations are done in suspected Osteomalacia?
bloods - vit D, calcium, phosphate (usually all low), raised ALP
XR - translucent bands
What investigations are done in suspected Paget’s bone disease?
blood - raised ALP, normal Ca2+/PO4-
Other markers - PINP, CTx, NTx, urinary hydroxyproline
XR - osteolysis in early disease
- later disease = mixed lytic/sclerotic lesions
skull XR - thickened vault and osteoporosis
Bone scintigraphy - increased uptake - focally active lesions
What investigations are done in suspected renal bone disease?
XR
- spinal XR shows sclerosis at both ends of vertebrae
- osteomalacia in centre of vertebra
What investigations are done in suspected osteosarcoma?
XR
Codman triangle and ‘sunburst pattern’
What investigations are done in suspected carpal tunnel syndrome?
nerve conduction studies
electrophysiological studies
What investigations are done in suspected ruptured achilles tendon?
mostly a clinical diagnosis
USS is usually used to confirm rupture
XR can be done r/o fractures and MRI to asses the nature/extent of rupture
What investigations are done in suspected bunion/Hallux Valgus & Hammer toes?
XR
- weight bearing
What investigations are done in suspected plantar fasciitis
usually a clinical diagnosis
What investigations are done in suspected morton’s neruoma?
US or MRI to confirm diagnosis
