MSK path VI Flashcards
can lead to pyogenic osteomyelitis
hematogenous spread
extension from a contiguous site
direct implantation
what microbe is majority of pyogenic osteomyelitis
staph aureus
what is microbe that can cause pyogenic osteomyelitis in sickle cell patient
salmonella because needs good Cā working to kill it
what is clearing dot on staph aureus culture
methicillin
child has subperiosteal abscess, suspect what
pyogenic osteomyeltiis
what is sequestrum
dead bone
brodie abscess
small intraosseous abscess that involves Cx and walled off by reactive bone
what is name of reactive bone that walls of pyogenic osteomyeltiis infection
involucrum
osteonecrosis of jaw
sclerosing osteomyelitis of Garre
what occurs if see sinus tract in skin oozing thick fluid looks like from bone
chronic pyogenic osteomyelitis
malaise fever, chills, leukocytosis, and throbbing pain over bone
hematogenous osteomyelitis
Dx osteomyeltisi
radiographic finding of lytic lesion surrounded by zone of sclerosis
what is required to identify pathogen in myelitis
Bx and bone cultures even if sample blood culture +
Tx osteomyelitis
antibiotics and surgical drainage
What is mycobacterial osteomyeltis
TB spondylitis (Pott disease) destructive
benign bone tumors Dx how
incidental finding
first hint of bone tumor usually
pathologic tumor
needed to definitively Dx bone tumor
bone Bx
window where bone tumor likely benign
1-30 y.o
most common primary cancer of bone
osteosarcoma
what are the malignant bone tumors
myeloma and lymphoma
hematopoietic spread
what are the benign cartilage forming tumors
osteochondroma
chondroma
chondroblastoma
chondromyxoid fibroma
what are the malignant cartilage forming tumors
chondrosarcoma
chondroblastomas involve what part of bone
epiphysis of long bones
chondromas affect what bones
small bones of hands and eet
osteochondroma affect what part of bones
metaphysis long bones
myelomas and lymphomas attack what bones
vertebrae and pelvis
difference of osteoid osteoma and osteoblastoma
size, sites of origin and Sx
what do osteoid osteomas and osteoblastomas look like grossly
round oval masses of gritty hemorrhagic tan tissue
rim of osteoid osteomas and osteoblastomas
single layer osteoblasts
what encircles osteoid osteoma lesion
lots of reactive bone
what is the center of osteoid osteoma called
nidus
what do cells of osteosarcoma produce
osteoid matrix or mineralized bone
most common primary malignant tumor of bone
osteosarcoma
peaks of osteosarcoma
<20 y.o
older adults
what is assoc with older age onset osteosarcoma
have pagets or bone infarcts or prior radiation
where fo osteosarcoma arise
long bones
metaphysis
50% around knee
presentation osteosarcoma
painful, progressively enlarging masses
can have sudden fracture
radiographs of osteosarcoma
large destructive mixed lytic and blastic mass with infiltrative margins
codman triangle
between Cs and periosteum
indicates aggressive tumor
distal lytic lesion in bone <20 y.o
osteosarcoma until proven otherwise
where o osteosarcomas mets
lungs
sites of osteosarcomas
intramedullary, intracortical or surface
most common subtype osteosarcoma
primary intramedullary, osteoblastic and high grade
color of osteosarcoma
tan white with areas of hemorrhage and cystic degeneration
pink stuff in aspirate of osteosarcoma
osteoid
prognosis osteosarcoma
if no mets 5 yr 60-70%
if mets <20% 5 yr
