Bone infections Flashcards
osteomyelitis
infection in bone
involucrum
new periosteal bone forms in response to infection
sequestrum
infected, dead bone sequestered by immune response
Brodie’s abscess
localized cystic osteomyelitis
MC in kids
What is acute heamtogenous osteomyelitis and who does it occur in
It is bone demineralization caused by a bloodborne pathogen
Occurs in kids, MC boys, metaphysis/epishysis, and in the lower extremeties
How does acute hematogenous osteomyelitis occur
A bloodborne pathogen infects a blood vessel in the bone, the bone demineralizes as the infection spreads (via expanding vessels)
Sequestrum and involucrum occur later in the ds
What is the most sensitive lab for AHO
CRP is most sensitive
ESR will also be elevated
What bacteria cause AHO in newborns
s. aureus, gran neg bacilli, group B strep
What bacteria cause AHO in children
s. aureus and group A strep
What bacteria cause AHO in adults
s. aureus
What is acute osteomyelitis
The pathogen infects the bone directly instead of via the blood stream
Clinical signs of subacute osteomyelitis
Brodie’s abscess
pain with weight bearing, no systemic sx
WBC and blood cultures are normal
Get an MRI
How do you tx subacute osteomyelitis
Curettage
Not abx because they don’t get to the bone
Important notes about chronic osteomyelitis
Be aware of SCC in sinus tract
sx may wax and wane
deep cultures are essential to dx
Important notes about septic arthritis
Rapid dx is essential
surgical emergency
hot, red, painful joint
pain w/ passive ROM
