Jaynstein - UE Topics in MSK Flashcards
what condition is caused by necrosis of bone dt interruption of blood supply
avascular necrosis
name 3 rf for avascular necrosis
etoh
coag d.o
steroids
what 3 bones are most commonly associated w. avascular necrosis
- head of femur or humerus
- scaphoid
- neck of talus
what is the 2 earliest sx of avascular necrosis
- pain w. activity/weight bearing
- decreased ROM
what is this sign and what is it associated with
crescent sign
avascular necrosis
what is the problem w. xrays in avascular necrosis
early xrays may be normal → late dx
what is the soc dx for avascular necrosis
advanced imaging → CT, MRI, bone scan
what is the first step in tx for avascular necrosis
ortho referral for all
what is the first step in suspected avascular necrosis if they have a negative work up
ortho referral for all!
you should treat all scaphoid avascular necrosis as if
it were broken
what is the tx for hip/shoulder avascular necrosis
almost all require replacement
what is the tx for scaphoid avascular necrosis
attempt to surgically restore blood flow →
debride and realign
OR
bone graft
__ accounts for 80-90% of osteomyelitis cases
s. aureus
what GI bacteria are associated w. osteomyelitis
e.coli
pseudomonas
klebsiella
what bacteria is associated w. osteomyelitis in ssa pt’s
salmonella
what 2 bacteria are associated w. osteomyelitis in neonates
h.flu
gbs
what lab values will be elevated in osteomyelitis
acute phase reactants
in osteomyelitis, ca, phos, and alk phos will usually be
normal
what will you see on xray of osteomyelitis (4)
- sts (soft tissue swelling)
- periosteal elevation
- cortical erosion
- lysis
→ bone necrosis
what is the problem w. xray for osteomyelitis
bone changes lag infxn by 14 days
__% of bone demineralization may have already occurred in osteomyelitis pt before it is seen on xray
30-50%
what is the first choice of imaging for osteomyelitis
MRI
CT is also helpful
what are 4 rf for osteomyelitis
kids
IVDU
DM
SSA
hardware
osteomyelitis is most common in
and >__ yo
<20
>50
what 2 bones are most commonly affected in osteomyelitis
long bones
vertebral bodies
what is the mc affected bone in dm w. osteomyelitis
toes/feet
what osteo condition do you think of when you see a pt who looks systemically ill w. malaise, f/c, leukocytosis, throbbing pain, and an open wound
osteomyelitis
what is the curative tx for osteomyelitis
abx + surgical drainage
what % of acute osteomyelitis infxns become chronic
5-25%
what 2 pt populations are at risk for chronic osteomyelitis
dm
immunocompromised
in osteomyelitis, ideally you begin abx tx after
c&s
what are 3 empiric abx choices for osteomyelitis
- Vanco + Ceftriaxone
- Cipro
- Cefepime
when should you tx a dm foot ulcer
if bone is visible
OR
if you can contact bone w. sterile probe
what are 4 complications of osteomyelitis
- pathologic fx
- endocarditis
- sepsis
- amputation
what is a benign bone lesion/slow growing tumor of little significance
osteoma
what are the 2 mc bones affected in osteoma
facial bones (nasal, ear)
skull
what do you think when you see exophytic growths attached to bone surface
osteoma
osteoomas are usually found
incidentally → xray or exam
what is the tx for osteoma
wait and see
vs
bx → if concern for malignancy
what do you call aggressive malignant, mesenchymal tumor of cancerous cells in the bone matrix
osteosarcoma
what is the mc bone cancer in kids
osteosarcoma
__% of osteosarcoma is in kids < 20 yo
75%
what are the 2 mc bones affected in osteosarcoma
long bones
jaw
what do you think when you see atraumatic bone pain and painful, progressively enlarging masses on the long bones or jaw
osteosarcoma
__% of osteosarcoma pt’s have mets at dx
20%
how do you describe the masses in osteosarcoma
endophilic
what imaging should you strongly consider when you dx osteosarcoma
CXR → evaluate for pulmonary mets
what is the tx for osteosarcoma (3)
- surgical excision
- XRT
- chemo
what is a hereditary condition that involves benign cartilage growth attached to underlying skeleton by a stalk
osteochondroma
what is the mc location for osteochondroma
metaphysis of long tubular bones
osteochondroma can be __
or __
solitary
multiple
osteochondromas are usually diagnosed
incidentally
what is the second mc malignancy in kids
ewing sarcoma
what are the 2 mc sites for ewing sarcoma
pelvis
proximal ends of long bones
what do you think when you see a kid with pain and inflammation around the head of the humerus, w. associated fever
ewing sarcoma
name 3 common lab findings in ewing sarcoma
- elevated ESR
- anemia
- leukocytosis
what do you think when you see onion peel appearance on xray
ewing sarcoma
any time you see an endothilic bone growth
do a cancer work up