Bone Infections Flashcards
what are the features of inflammation
rubor calor dolor tumor functio laesa
what blood tests are the most useful
CRP and PV- show inflammation
what blood tests are occasionally useful
blood cultures, white cell count, ESR
what is a brodies abscess
a subacute osteomyelitis, which may persist for years before converting to a frank osteomyelitis
what does a technetium scan do
osteoblast activity
how can MRI help in infection
shows puss, inflammatory processes and water content
who gets osteomyelitis
post traumatic/ open fracture (inoculation)
children/ immunosuppresed (haematogenous)
what are the most common causative agents of acute osteomylelitis
staph aureus
haemophilus in children
how can a minor trauma cause acute osteomyelitis
damages sinusoidal vessel causing a thrombosis in metaphysis
what happens in chronic osteomyelitis
sclerotic changes due to osteoclast activity cause bone death over a wide area (sequestrum) which causes a lifted periosteum
what tests can be done in osteomyelitis
blood tests often UNhelpful
plain x rays and MRI
why can osteomyelitis be chronic
as bugs can be dormant
what is am involucrum
involucrum (plural involucra) is a layer of new bone growth outside existing bone seen in pyogenic osteomyelitis. It results from the stripping-off of the periosteum by the accumulation of pus within the bone, and new bone growing from the periosteum
how can bugs gets into the joint in septic arthritis
inoculation
metaphyseal spread
direct haematogenous
what are gas forming organisms in soft tissue associated with
necrotising fascitis
