OB 3 Flashcards
primary blood supply to growth plate
Perichonodral
tumors with “small blue cells”
Neuroblastoma, primitive neuroectodermal tumors (PNET), Ewing’s sarcoma, and embryonal rhabdomyosarcoma
CRPS Type II is like type I but _
in a single nerve distribution
10 year % Hip fracture and overall osteoporotic fracture threshold to start bisphosphonates
3%, 20%
pectus excavatum is associated with?
marfan’s
Tx for intramuscular myxoma?
excision alone
Homogenous mass on MRI bright on T2, dark on T1 unlike lipoma (matches fat on everything)?
myxoma
ankle position with lowest calf compartment pressures?
neutral to 30 degrees plantar flexion
Treatment of elderly olecranon fractures with good outcomes?
Cast, early mobilization
Letter at end of iCD-10 means what?
what phase of care. Initial/subsequent/sequelae
What sided IT fractures are at risk for malreduction and what type of malreduction?
left sided from screw insertion, Apex anterior of the proximal segment
Definitive diagnosis of ALS is with what modality?
electrodiagnostic tests
tibiotalar impingement in calcaneus fracture malunions caused by?
decreased calc height causing talus dorsiflexion and impingment
Component of bone responsible for its compressive strength?
proteoglycans and hydroxyappetite
Blood volume in normal adult?
5L
Blood loss in Grade I
<15%
Blood loss in grade II
15-30%
Blood loss in grade III
30-40%
Blood loss in grade IV
> 40%
MOA penicillins
cell wall synthesis
MOA cephalosporins
cell wall synthesis
MOA vancomycin
cell wall synthesis
MOA -penems
cell wall synthesis
MOA aminoglycosides
anti 30s ribosomal subunit (mycins)
MOA tetracyclines
anti 30s ribosomal subunit
MOA Macrolides
anti 50s ribosomal subunit (thromycins)
MOA Linezolid
anti 50s ribosomal subunit
MOA Flouroquinolones
DNA gyrase (floxacins)
MOA Rifampin
RNA synthesis via RNA polymerase
MOA bactrim
folic acid synthesis
Arterial supply to flap in calc extensile lateral?
lateral calcanea branch of peroneal artery
Fractures in OI should be treated with _ fixation when possible
intramedullary; plates put adjacent bone at risk of fracture
Only remaining blood supply to talus after talar neck frx?
deltoid branch of posterior tib that sits within the deltoid ligament
mech of inheritance of osteopetrosis
auto recessive
t/f: DBM is osteoinductive and conductive
true
MOA anakira?
IL-1 antag
medium to long term muscle weakness after antegrade femoral nailing?
hip abduction and knee extension
Hoffa fracture more common in what condyle?
lateral
Canals that connect mature osteocytes?
Cannaliculi
Does PT improve outcomes/motion after DR ORIF?
No
Most common side effect of indomethacin?
GI (stomach ulceration)
Increased energy for unilateral BKA
25
Increased energy for b/l BKA
40
Increased energy for AKA
65
Nerve roots for perianal sensation?
S1. S2
Most common malreduction of distal 1/3 tibia with infrapatellar nail
valgus
Most common complication after talar neck fx?
tibiotalar or subtalar djd
Structure that blocks reduction of medial subtalar dislocation?
EDB
Structure that blocks reduction of lateral subtalar dislocation?
posterior tib tendon
What molecule thought to be released during dissection puts postop THA/TKA patients at risk of DVT?
thromboplastin
Tumor marker associated with colorectal
CEA
pelvic ring injury with highest rate of transfusion?
APC 3
What seen on an EMG for radial nerve palsy 6 months after injury represents signs of recovery?
fasciculations
What seen on an EMG for radial nerve palsy 6 months after injury represents no signs of recovery and pushes towards surgical exploration?
fibrillations
Predictors of humeral head AVN after fx?
calcar length less than 8 mm > disrupted medial hinge > humeral head angulation more than 45 degrees > head-split fracture
Vaughn Jackson Syndrome is
Sequential rupture of digital extensors in RA
Bone substitute that resorbs the fastest?
calcium phosphate
Bone overgrowth in pediatric amputations is seen in what types of amputations?
BKA/AKA - transosseous. Avoided with knee disartic
Most common malrotation of proximal femoral shaft fractures?
IR (proximally frag is in ER by hip external rotators)
Most common malrotation of distal femoral shaft fractures?
ER (Distal fragment pulled by lateral head of gastroc?)
Most sensitive way to diagnose pediatric spondy when XR are normal
SPEC CT
Diastrophic dwarfish is caused by a mutation in what gene that serves what function?
DTD, Sulfate transport protein
telangiealitic osteosarcoma is radiographs and histologically similar to _
ABC
Unicortical locked screws compared to bicortical non locked screws in a plate have _ resistance to axial forces, and _ resistance to torsional forces
increased, decreased
penecillin is given for barnyard/soil injuries to cover what organism?
Clostridia
get up and go speed of less than _ seconds is predictive of assistive device free ambulation at 2 years?
12 seconds
is smoking associated with postop airway complications in acdf?
no
Most common site of PIN entrapment?
arcade of Froshe
lesion in zone 1 of guyon’s canal affect _
motor (including hypothenar) and sensory
lesion in zone 2 of guyon’s canal affect _
motor only (not hypothenars, only Interossei and thenar)
lesion in zone 3 of guyon’s canal affect _
sensory only
most common organism in wounds from cat/dog bites?
pasteurella
Excessive anterior retraction during Watson jones can injure what structure?
femoral nerve
ETO for revision THA has what material effect on femur?
Reduces torque to failure by 50% compared to intact bone
Most common foot deformity with myelomeningocele?
clubfoot
wORST material for injection injury?
oil based paints or industrial solvents
When performing LRTI what two things should be examined?
STT joint, MCP joint hyperextension (fusion)
During LRTI the FCR tendon reconstructs what ligament?
First intermetacarpal
Type of corrosion that leads to failure at junction in modular THA stems?
fretting
amount of diaphysis for press fit of fully porous coated stem in revision?
4cm
amount of diaphysis for press fit of modular tapered stem in revision?
2cm
“safe” angles for acetabulum cup
30-50, 5-25
most common cause of TKA revision in first 2 years?
infection
Computer based neurocog test used for baseline and after concussion?
ImPACT
“Overall” rate of distal femur physical arrest after physical fracture?
60%
Besides anterolateral bowing and congenital pseudoarthrosis of the tibia, NF can be associated with what other deformity?
Bowing of the forearm
treatment for chondroblastoma?
curettage +/- adjuvants, bone grafting
Multiple lesions that appear to be multiple metastatic lesions but have variable appearance can also be caused by?
hyperparathyroidism
Mass that pathonomically occurs at inferior angle of scapula and its treatment?
elastofibroma, exision alone
most common met to hands and feet?
lung
Only soft tissue sarcoma where chemo has effect?
rhabdomyosarcoma
Most to least predictive of humeral head ischemia after fracture
calcar < 8mm, disrupted medial hinge, head angulation > 45 degrees, head split
pediatric femur fractures or placement of tibial traction pins in kids can lead to _ deformity?
recurvatum
Hip deformity that can be seen with Marfans
protrusio
histology finding for schwannoma?
veracoy bodies
Shoulder functional scores between ORIF and IMN are _
the same (stiffness and pain are higher after IMN)
Does timing of ORIF with fasciotomy closure affect infection rates in tibial plateau fractures?
no
Adductor policis is innervated by _
ulnar nerve
max rotational difference after femur IMN that is acceptable?
15 degrees
primary bone healing is _
intramembranous
Secondary bone healing is _
enchondral (callus)
Normal 1-2 IMA
<13
Normal DMAA
<10
Normal Halux valgus interphalangeus angle?
<10
Normal Hallux valgus angle
<15
Biplanar chevron vs uniplanar chevron osteotomy for hallux valgus has what advantage?
Corrects DMAA
Factor associated with poor outcomes in pediatric radial neck fractures after surgical fixation?
age > 10
Contrindication to humeral IMN?
radial nerve palsy
Poland syndrome associated with what hand deformity?
syndactyly
sensory distribution of femoral nerve?
anteromedial thigh (medial cutaneous nerve of thigh), medial shin (saphenous nerve)
imagining modality to assess chronicity of compression fx?
MRI
Adjacent level fusion required after Lumbar PSIF at 5 and 10 years?
15%, 36%
Adjacent level fusion required after cervical fusion annually and 10 years?
2.5% per year, 25%
minimum ACL Graft size
8mm (btb and HS)
Type of joint degeneration with inflammatory arthritis?
symmetric without osteophyte formation
Throwers get retroversion of humeral head, glenoid, or both?
both
T/F: pulse lavage for open fractures increases postop wound necrosis?
true
contraction ring syndrome (amniotic band) is associated with what foot deformity?
clubfoot
Secondary primary contributor to femoral head blood supply?
IGA
released by macrophage to activate osteoclast in total joint osteolysis
TNF alpha (and RANKL)
tensor fascia latta is innervated by _
SGn
Do pre aspiration abx affect alpha anti defensin result?
no
MOA of abatacept?
MHC receptor antag
First to be lost and last to return after peripheral nerve injury?
motor
D zone test is for detecting inducible resistance to. _
clinda
MOA LMWH
Xa inhibitor
MOA heparin
Antithrombin III activator
BMP peaks in biomembrane after 1st stage masquelet at how many months?
1
tenderness to central part of the heel after multiple CSI for plantar fasciitis?
heel pad atrophy
first line tx for anterolateral tibial bowing with development of fracture?
casting, open tx with bone grafting if fails to heal and goes on to pseudarthrosis
abx to use for prophylactic coverage when using leeches?
Bactrim (aeromonas hydrophilia bacteria)
Familial hyperphosphatemic tumoral calcinosis associated with what mutation?
FGF 23
spindle cell lipoma treated with _
resection alone, no radiation
In addition to correcting SVA, in adult ASD, the goal is to correct _ to within 10 of _
lumbar lordosis, pelvic incidence
inheritance of rett syndrome?
x linked dominant
airbags should be turned off in front seat for children < _ lbs
80
gram-negative intracellular diplococci on gram stain is _
gonorrhoeae
physiologic inflammatory response to trauma is _ in children compared to adults
decreased
trauma is associated with bone/joint infxn in kids _% of time
30
flexion type SCH pinned in what elbow position?
ext
AP position for anterior column screw within the ramus on _ view
iliac inlet
SI position for anterior column screw to rule out joint penetration on _ view
Obturator outlet
M/L position within iliac wing for anterior column screw on _ view
Obturator inlet
collagenase has little effect on type _ collagen, thereby pretecting NV bundles
IV
Free fibula based on what arterial supply
peroneal
most common UMN sign that can be seen in those without spinal cord compression?
hyperreflexia
most common nerves injured in distal biceps repair?
LABC, PIN
Gait exam finding that is contraindication to Valgus HTO?
varus thrust
Vertical cup eliminates what THA design that decreases instability?
large head
What type of femoral shaft fracture under 3 years is associated with NAT (not metaphyseal)
transverse
Muscle that becomes the primary deforming force for producing hallux valgus
adductor hallicus
pedicle for medial femoral vascularized bone graft?
longitudinal branch of the descending geniculate artery
Standard THA neck angle
131
“Varus” THA neck angle that allows increased offset without increasing leg length
127
IV abx for p. acnes coverage
Penecillin
Metal most susceptible to pitting corrosion
stainless steel
Factors involved in osteolysis
IL1, IL6 TNF alpha, rankl
MOA of calcitonin
inhibits sclerostin formation and inhibits osteoclast apoptosis
MOA fondaparinux
Inhibition of factor X
MOA Enteracept
Binds TNF alpha receptor
MOA all “abs” for RA
bind TNF alpha directly
peripheral nerve layer that must be intact for nerve to regrow?
endoneurium
first carpal bone to ossify
capitate (starts at capitate, then hamate, triq, lun, scap, trapezium, trapezoid, pisiform)
foot deformity of chronic lisfranc injury
planovalgus
Besides IMA, what can a distal chevron osteotomy for hallux valgus not correct?
metatarsal pronation
gout crystal shape
needle, negative birefrigent
pseudo gout crystal shape
rhomboid, positive birefrigent
first portal established for ankle scope
anteromedial
pedicle for lat flap
thoracodorsal art
pharmacotherapy for Raynaud
topical nitrates
Tumor of finger that often leads to amputation
subungal melanoma
primary stabilizer of thumb cmc joint?
volar oblique (or beak) ligament
type of radiation used near critical structures like spinal cord
proton beam
standard type of XRT
photon beam
factor associated with PVNS
colony-stimulating factor 1 (CSF-1).
Common gene mutation in osteosarcoma
P53
Congenital scoliosis often runs in families?
false. sporadic, <1% of family history
inheritance of cleft hand or foot?
AD
congenital glenohumeral dyplasia results in:
humeral head flattening, glenoid retroversion, poster subluxed humeral head
joints with intra artic metaphysis
hip, elbow, ankle, shoulder
most common exam finding for isthmus spondylolysis?
hamstring tightness
kocher interval is
aconeus and ECU
kaplan interval is
EDC/ECRB
Elbow lateral pivot shift is done by _
extension, then flexing the elbow with valgus and supination moments along with axial compression.
cause of persistent back pain after multiple surgeries, etc.
central sensitization
scheurerman kyphosis is serpositive?
true
risk of radial nerve palsy with holstein lewis fx?
22%
iatrogenic radial nerve palsy most commonly occurs during what two approaches?
lateral and posterior
