RADIOLOGY OF OSTEOMYELITIS Flashcards
pathophysiology?
key to success is?
involves both the cortex and medullary canal
rapid diagnosis
steps to take to treat diabetic patient with infected foot ulcer, possible osteomyelitis?
*diagnostic gold standard for OM?
plain film radiographs and probe to bone test
MRI, if necessary, and then
bone biopsy
*bone biopsy
how is OM classified?
presentation and routes
presentation
- acute
- subacute
- chronic
routes based
- hematogneous (blood infection)
- direct extension (soft tissue infection)
- direct inoculation (step on nail)
generally a disease of growing bone occurring most commonly in infants and children
acute hematogenous OM
clinical features of acute hematogenous OM and pathophysiology?
pain, swelling, erythemia
infection starts in the metaphysis and then spreads
what are the ages of acute hematogenous OM onset?
infantile
juventile
adult
vascular communication btwn the metaphysis and epiphysis and once it gets to the epiphyses it can spread into the joint cavity?
what age is affected by this acute hematogenous OM
infantile
vascular channel closed off
lower risk of OM except at some joints like hip
what age is affected by this acute hematogenous OM
juvenile
growth plate gone so metaphysis goes to epiphysis and septic arthritis occurs
usually rare in adults, less so than juveniles
we see in drug abusers, sickle cell and immunosuppressed
what age is affected by this acute hematogenous OM
adult
when is acute hematologic OM increased?
infants and adults
radiographic changes seen in acute hematologic?
reparative changes in bones occur about 10 days after onset
most common pedal site for acute HOM is calcaneus
lags behind progression of disease
radiographically what happens to bone in acute hematologic OM?
periosteal
endosteal
cortical
radiographically, 2-3 days changes in acute hematologic OM?
inflammatory ST swelling
radiographically, 10-14 days changes in acute hematologic OM?
radiographic changes show up
- patchy internal lysis
- focal ostepenia
- periosteal new bone formation
- minmal cortical destruction/erosion
most common pedal site for acute HOM?
calcaneus, presents with lytic changes
T/F, radiographic findings lag behind clinical course/progression of disease?
T
more likely occurring in an older population so less likely to present as a periosteal reaction as the periosteum is more tightly adhered but still happens, not as dramatic
direct extension OM, this moves from periosteal space to medullary space beginning as an infection
what are the radiologic changes?
early osseous changes 10-14 days
- focal osteopenia
- loss of cortical lysis at the onset
- periosteal reaction is variable
where is general OM mostly seen in the foot?
metatarsal and proximal phalanges
common characteristics of General OM once periosteal reactions are observed?
when an osseous infection is observed what imaging is used to help diagnose and determine extent of infections?
no periosteal rxns in the tarsal bones
distal and intermediate phalanges are rare
MRI, marrow edema being present
