MSK Arthritis Flashcards

1
Q

arthritis –> 5 broad categories?

A
  • degen
  • inflamm
  • xl deposit
  • hematologic
  • metab
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2
Q

OA –> key XR findings? (5)

A
  • jt space narrow –> asymm
  • subchondral sclerosis
  • osteophyte
  • subchondral cyst
  • no periarticular osteopenia
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3
Q

XR findings of OA –> +extensive subchondral cysts –> ddx? (2)

A
  • OA

- calcium pyrophosphate dihydrate xl deposit dz (CPPD)

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4
Q

what is Heberden node? Bouchard node?

A

Heberden: OA –> DIP –> lrg osteophyte –> ST swelling

Bouchard: PIP

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5
Q

what is Grashey view?

A

shoulder –> 40deg obliqued ext rot –> glenohumeral jt in profile

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6
Q

OA –> foot –> 2 common locations?

A
  • 1st MTP

- talonavicular jt

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7
Q

OA –> 1st MTP –> potential complication?

A

dorsal osteophytes –> stiff big toe (hallux rigidus)

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8
Q

differentiate –> hip –> OA vs inflamm arthritis –> femoral head migration?

A
  • OA: #1 superolat; less common med

- inflamm: axial

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9
Q

RA –> hip –> potential comp?

A

severe axial migration –> protrusio acetabuli

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10
Q

intervertebral discs –> 3 components?

A
  • nucleus pulposus
  • annulus fibrosus
  • cartilaginous endplates
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11
Q

uncovertebral jt –> what levels?

A

C3-C7

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12
Q

what is degen disc dz (DDD)? charact by what findings? (3)

A

spectrum of intervertebral disc degen:

  • disc dessication
  • endplate sclerosis
  • osteophytosis
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13
Q

vacuum phenomenon –> pathognomic for what condition?

A

degen disc dz (DDD)

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14
Q

what is Kummel dz?

A

trauma –> avascular necrosis –> wks-months later –> progressive vertebral body collapse –> gas within vertebral body

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15
Q

diffuse idiopathic skeletal hyperostosis (DISH) –> definition? (3)

A
  • flowing bridging ant osteophytes –> 4 levels
  • normal disc space
  • normal SI jts
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16
Q

diffuse idiopathic skeletal hyperostosis (DISH) –> assoc condition?

A

osiffication of post long lig (OPLL) –> spinal stenosis

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17
Q

diffuse idiopathic skeletal hyperostosis (DISH) –> potential comp?

A

cervical spine –> dysphagia

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18
Q

sacroiliac jt –> superior portion is what type of jt? inf?

A
  • sup –> syndesmotic

- inf –> synovial

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19
Q

OA –> SI jt –> which part is affected?

A

inf –> synovial jt

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20
Q

erosive OA –> what is similar to OA? RA?

A

RA –> clinical findings –> ie swelling

OA:

  • distribution
  • imaging findings
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21
Q

erosive OA –> distribution?

A

hands only –> DIP, PIP, 1st CMC

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22
Q

erosive OA –> characteristic xray finding?

A

DIP –> central erosion + marginal osteophyte –> “gull wing” appearance

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23
Q

rheumatoid arthritis –> MOA?

A

autoimmune disorder –> immune response –> wax & wane –> synovium

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24
Q

RA –> key XR findings? (5)

A
  • symm jt space narrow
  • marginal erosion
  • periarticular osteopenia
  • jt subluxation
  • ST swelling
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25
Q

RA –> earliest XR findings? (2)

A

synovitis & hyperemia:

  • ST swell
  • periarticular osteopenia
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26
Q

RA –> hand –> early erosions –> typical locations (3)

A
  • 2nd & 3rd metacarpal –> head –> radial aspect
  • prox phalanx –> base –> radial & ulnar aspect
  • ulnar styloid
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27
Q

RA –> hand –> jt sublux –> 3 common deformities?

A
  • Boutonniere: PIP flex, DIP hyperext
  • Swan neck: PIP hyperext, DIP flex
  • MCP –> digits –> ulnar sublux
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28
Q

RA –> wrist –> late-stage dz –> potential comp?

A

complete cartilage loss –> fibro-osseous jt fusion –> carpal ankylosis

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29
Q

RA –> foot –> which jts? (2)

A
  • MTP

- talocalcaneonavicular

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30
Q

protrusio acetabuli –> measuremts?

A

femoral head –> medial deviation –> past ilioischial line:

  • M: >3mm
  • F: >6mm
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31
Q

knee –> all 3 compartmts –> symm jt space narrow –> osteophytes –> ddx? (1)

A

2ary OA

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32
Q

knee –> what XR finding indicates presence of OA? what XR finding indicates severity of OA?

A
  • osteophyte –> presence of OA

- jt space narrow –> severity of OA

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33
Q

RA –> knee –> which compartmt MC involve?

A

all 3

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34
Q

RA –> knee –> erosions NOT prominent manifestation –> T/F?

A

T

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35
Q

RA –> cervical spine –> atlantoaxial sublux –> 5 types?

A
  • ant
  • post
  • vertical (AA impaction)
  • rotatory
  • lat
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36
Q

RA –> cervical spine –> atlantoaxial sublux –> ant type –> MOA?

A

adj bursa –> inflamm –> transverse lig –> lax

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37
Q

RA –> cervical spine –> atlantoaxial sublux –> ant type –> measuremts?

A

atlanto-dental interval:

  • adult: >2.5mm
  • child: >5mm
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38
Q

RA –> cervical spine –> atlantoaxial sublux –> ant type –> what kind of image view?

A

flexion

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39
Q

RA –> cervical spine –> atlantoaxial sublux –> vertical (AA impaction) type –> MOA?

A

C1-C2 facet –> erosion –> collapse –> odontoid –> protrude into foramen magnum

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40
Q

RA –> cervical spine –> atlantoaxial sublux –> vertical (AA impaction) type –> potential comp?

A

compress midbrain

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41
Q

RA –> shoulder –> potential comp?

A

chronic rotator cuff tears –> high riding humerus

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42
Q

high riding humerus –> ddx? (3)

A
  • rotator cuff tear
  • RA
  • CPPD
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43
Q

RA –> shoulder –> erosions –> MC locations? (2)

A
  • humerus –> lat aspect

- AC jt –> distal clavicle “penciling”

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44
Q

seroneg spondyloarthropathy –> assoc w what lab finding?

A

+HLA-B27

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45
Q

what are the 4 seroneg spondyloarthropathies?

A
  • ank spondylitis
  • psoriatic arthritis
  • reactive arthritis (Reiters)
  • IBD-assoc arthropathy
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46
Q

seroneg spondyloarthropathies –> hallmark finding?

A

sacroiliitis

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47
Q

seroneg spondyloarthropathies –> sacroiliitis –> involves which portion of SI jt?

A

inf portion –> synovial jt

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48
Q

sacroiliitis –> bilat –> symm –> ddx? (2)

A
  • IBD

- ank spond

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49
Q

sacroiliitis –> bilat –> asymm –> ddx? (2)

A
  • psoriatic arthritis

- reactive arthritis

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50
Q

sacroiliitis –> unilat –> ddx? (1)

A

septic arthritis

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51
Q

what conditions assoc w IBD-sacroiliitis? (4)

A
  • ulc colitis
  • Crohns
  • Whipple dz
  • s/p gastric bypass
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52
Q

ank spond –> assoc lung/heart conditions? (3)

A
  • pulm fibrosis
  • aortitis
  • cardiac conduction defect
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53
Q

ank spond –> earliest XR findings?

A

symm sacroiliitis:

  • erosions
  • widening
  • sclerosis
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54
Q

ank spond –> what is Romanus lesion?

A

vertebral body –> endplate –> anterior –> sup or inf –> enthesitis –> erosion

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55
Q

ank spond –> what is shiny corner?

A

Romanus lesion –> sclerosis

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56
Q

ank spond –> what is “squaring”?

A

vertebral body –> loss of normal concavity of the anterior border –> “squaring”

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57
Q

ank spond –> what is Andersson lesion?

A

spine –> completely ankylosed –> pseudoarthrosis

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58
Q

psoriatic arthritis –> MC location? 2nd MC?

A
#1 hands
#2 feet
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59
Q

ivory phalanx –> dx?

A

specific sign for psoriatic arthritis

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60
Q

differentiate: psoriatic arthritis vs degenerative –> plantar calcaneal spur?

A

PsA spur –> periosteal rxn

degen spur: no periosteal rxn

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61
Q

reactive arthritis –> potential comp of what conditions? (3)

A

infxn:
- diarrhea
- urethritis
- cervicitis

62
Q

reactive arthritis –> MC location?

A

feet –> particularly calcaneus

63
Q

reactive arthritis –> XR findings? (6)

A
  • diffuse ST swell
  • jt space narrow
  • marginal erosions –> aggressive
  • periarticular osteopenia
  • bony prolif
  • enthesitis
64
Q

reactive arthritis –> imaging appearance –> similar to what other condition?

A

psoriatic arthritis

65
Q

ballcatcher’s (Norgaard) view –> purpose?

A

better visualize jt erosion

66
Q

systemic lupus erythematosus (SLE) –> arthritis –> key XR finding?

A

MCP & PIP –> sublux –> reducible (seen on Norgaard view, normal on PA)

67
Q

MCP & PIP –> reducible subluxations –> ddx? (2)

A
  • SLE

- Jaccoud arthropathy

68
Q

what is scleroderma?

A

systemic –> collagen vascular dz –> collagen deposited –> skin, soft tissue

69
Q

scleroderma –> 1st affected location?

A

fingertips –> soft tissue atrophy

70
Q

acro-osteolysis –> ddx? (6)

A
  • collagen vascular dz (ie scleroderma)
  • neuropathy
  • polyvinyl chloride exposure
  • thermal injury
  • hyperPTH
  • Hajdu-Cheney
71
Q

Hajdu-Cheney –> synd? (3)

A

autosomal dominant:

  • short stature
  • craniofacial changes
  • progressive acro-osteolysis
72
Q

scleroderma –> jt contracture –> MOA?

A

calc –> soft tissue & periarticular -> skin tighten & fibrosis –> jt contracture

73
Q

dermato/polymyositis –> imaging hallmark?

A

ST calc –> intra-musc

74
Q

what is calcium hydroxyapatite deposition dz (HADD) (aka calcific tendinitis)?

A

hydroxyapatite xls –> deposit in tendons

75
Q

calcium hydroxyapatite deposition dz (HADD) (aka calcific tendinitis) –> MC location?

A

rotator cuff –> supraspinatus tendon

76
Q

what is Milwaukee shoulder?

A

HADD –> intra-articular variant –> rotator cuff, glenohum jt –> rapid destruct

77
Q

calcium hydroxyapatite deposition dz (HADD) (aka calcific tendinitis) –> longus coli –> can clinically mimic what condition?

A

prevertebral abscess:

  • neck pain
  • odynophagia
  • fever
  • prevertebral effusion
78
Q

differentiate: CPPD vs gout: birefringence?

A

gout: neg
CPPD: positive

79
Q

calcium pyrophosphate dihydrate deposition dz (CPPD) –> etiology? (4)

A
  • idiopathic
  • hemochromatosis
  • hyperPTH
  • hypoPhosphate
80
Q

calcium pyrophosphate dihydrate deposition dz (CPPD) –> key XR finding?

A

chondrocalcinosis

81
Q

calcium pyrophosphate dihydrate deposition dz (CPPD) –> can clinically similar to what conditions? (5)

A

great mimicker:

  • asympt
  • gout
  • OA
  • RA
  • neuropathic
82
Q

calcium pyrophosphate dihydrate deposition dz (CPPD) –> wrist –> MC location?

A

triangular fibrocartilage complex (TFCC)

83
Q

calcium pyrophosphate dihydrate deposition dz (CPPD) –> wrist –> potential complication?

A

scapholunate advanced collapse (SLAC)

84
Q

scapholunate advanced collapse (SLAC) –> etiology? (3)

A
  • CPPD
  • RA
  • trauma
85
Q

scapholunate dissociation –> sign? measuremt?

A

Terry thomas sign: scapholunate interval >4mm

86
Q

knee –> what findings are highly suggestive of CCPD? (2)

A
  • degen changes –> patellofemoral cmpt only

- prominent subchondral cysts

87
Q

CPPD –> hand –> MC location? charact finding?

A

2nd & 3rd MCP –> radial aspect –> “hook-like”/”drooping” osteophyte

88
Q

hand –> MCP heads –> “hook-like” osteophytes –> ddx? (2) how differentiate?

A
  • CPPD: 2nd & 3rd

- hemochromatosis: all

89
Q

gout –> hallmark findings? (3)

A
  • erosions –> sharp margins
  • overhanging margins
  • soft tissue gouty tophi
90
Q

gout –> etiology?

A

excess uric acid:

  • # 1 under-excrete (ie. renal insuff)
  • over-produce
91
Q

gout –> jt space –> normal vs narrow?

A

normal –> until late dz

92
Q

hemochromatosis arthropathy –> MOA?

A

deposit:
- iron
- calcium pyrophosphate dihydrate xls

93
Q

hemochromatosis –> clinical presentation (5)

A
  • bronze pigmentation
  • DM
  • cirrhosis
  • CHF
  • arthritis
94
Q

acromegaly –> arthritis –> MOA?

A

articular cartilage –> enlrg –> jt space widen –> later –> 2ary OA –> jt space narrow

95
Q

acromegaly –> arthritis –> hand –> charact findings? (2)

A
  • metacarpal head –> “beak-like” osteophytes

- terminal tufts –> “spade-like” enlrg

96
Q

amyloidosis –> RF? (3)

A
  • monoclonal plasma cell dyscrasia
  • chronic inflamm/infx
  • chronic dialysis
97
Q

amyloid arthropathy –> charact finding?

A

shoulder –> bulky soft tissue nodules + muscle atrophy –> “shoulder pad” sign

98
Q

amyloid arthropathy –> imaging findings can be similar to what condition?

A

RA

99
Q

what is ochronosis?

A

connective tissue manifestation of alkaptonuria: homogentisic acid oxidase –> defect –> homogentisic acid –> accum –> organs, jts, discs

100
Q

ochronosis/alkaptonuria –> arthropathy –> key finding?

A

every level intervert disc –> calc & narrow

101
Q

what is multicentric reticulohistiocytosis?

A

rare –> lipid-laden macrophage –> deposit in soft tissues, tendons –> skin nodules, erosions

102
Q

multicentric reticulohistiocytosis –> XR findings? (3)

A
  • erosions –> sclerotic margins
  • ST nodule
  • normal bone density
103
Q

multicentric reticulohistiocytosis –> MC distribution?

A

DIP –> symm

104
Q

multicentric reticulohistiocytosis –> potential comp?

A

rapid jt destuct –> arthritis mutilans

105
Q

hemophilia –> arthropathy –> MOA?

A

recurrent hemarthrosis –> synovium –> hyperemia & hypertrophy –> epiphysis enlrg –> early fusion –> 2ary arthritis

106
Q

hemophilia –> arthropathy –> MC locations? (3)

A
  • knee
  • ankle
  • elbow
107
Q

hemophilia –> arthropathy –> elbow –> charact appearance? (2)

A
  • enlrg radial head

- wide trochlear notch

108
Q

hemophilia –> arthropathy –> knee –> charact appearance? (2)

A
  • square patella

- wide intercondylar notch

109
Q

elbow –> enlrg radial head –> ddx? (2)

A
  • hemophilia

- juvenile idiopathic arthritis (JIA)

110
Q

knee –> wide intercondylar notch –> ddx? (2)

A
  • hemophilia

- juvenile idiopathic arthritis (JIA)

111
Q

what is pseudotumor of hemophilia?

A

recurrent intraosseous/subperiosteal bleed –> ST mass –> bony scallop, pressure erosion

112
Q

pseudotumor of hemophilia –> XR appearance? MRI?

A

XR: benign –> well-circum, sclerotic margin

MRI: complex –> diff stage blood products

113
Q

juvenile idiopathic arthritis (JIA) –> age?

A

<16yo

114
Q

what is Still dz?

A

JIA variant –> systemic

115
Q

Still dz –> age?

A

<5yo

116
Q

Still dz –> synd? (5)

A
  • acute febrile illness
  • rash
  • adenopathy
  • pericarditis
  • mild arthralgia
117
Q

juvenile idiopathic arthritis (JIA) –> types? (3) MC?

A
  • # 1 pauciarticular
  • monoarticular
  • polyarticular
118
Q

juvenile idiopathic arthritis (JIA) –> key finding?

A

skeletally immature –> bone length/morphology –> abnormal

119
Q

juvenile idiopathic arthritis (JIA) –> bone shortening, abnormal morphology –> MOA?

A

hyperemia –> epiphysis:

  • overgrow & enlrg (“ballooning”)
  • premature physeal fusion –> brachydactyly
120
Q

JIA –> knee –> imaging appearance? (3) similar to what condition?

A
  • wide intercondylar notch
  • metaphyseal flare
  • uniform jt narrow

similar to hemophilia

121
Q

JIA –> elbow –> imaging appearance? (3) similar to what condition?

A
  • wide trochlea notch
  • radial head enlrg
  • uniform jt narrow

similar to hemophilia

122
Q

JIA –> hip –> imaging appearance? (3)

A
  • uniform jt narrow
  • protrusio deformity
  • femoral shaft –> gracile appearance
123
Q

child –> cervical spine –> ankylosis –> ddx? (2)

A
  • JIA

- Klippel-Feil synd

124
Q

what is Klippel-Feil synd?

A

dev disorder –> fail cervical segmentation –> fusion of 2 or more cervical vertebrae

125
Q

JIA –> advanced dz –> ankylosis –> location? (2)

A
  • wrist

- cervical spine –> facet jts

126
Q

cervical ankylosis –> MC in JIA or RA?

A

JIA

127
Q

neuropathic arthropathy (Charcot jt) –> 2 types?

A
  • # 1 hypertrophic

- atrophic

128
Q

neuropathic arthropathy (Charcot jt) –> hypertrophic variant –> imaging appearance?

A

“anarchy in a jt”:

  • destrucxn
  • sublux/dislocate
  • debris
  • disorg
  • no demin
129
Q

neuropathic arthropathy (Charcot jt) –> atrophic variant –> MC location? imaging appearance?

A

shoulder –> humeral head resorption –> sharp surg-like margin

130
Q

neuropathic arthropathy (Charcot jt) –> UE –> next step?

A

suspect syringomyelia –> MRI cervical

131
Q

sarcoidosis –> MSK manifestation? (2)

A
  • bone lesion

- polyarthritis

132
Q

sarcoidosis –> bone lesion –> imaging appearance?

A

mid or distal phalanx –> lytic lesion –> “lace-like”

133
Q

b/l ankle –> arthritis & erythema nodosum –> next step?

A

suspect sarcoidosis –> CXR

134
Q

diffuse osteopenia –> assoc arthritis?

A

advanced RA

135
Q

periarticular osteopenia –> assoc arthritis? (2)

A
  • RA

- any inflamm arthropathy –> early stage

136
Q

DIP ankylosis –> what arthritis?

A

psoriatic arthritis

137
Q

hand –> DIP & PIP –> osteophytes –> what arthritis?

A

OA

138
Q

hand –> DIP & PIP –> osteophytes + erosions –> what arthritis?

A

erosive OA

139
Q

hand –> DIP & PIP –> erosions, no osteophytes –> what arthritis?

A

psoriatic OA

140
Q

RA –> distal radioulnar jt –> sequential extensor tendon rupture –> in what order?

A

ulnar to radial: 5 –> 4 –> 3 –> 2

141
Q

tenosynovitis –> focal –> etiology? (2)

A
  • penetrating infx

- overuse

142
Q

tenosynovitis –> diffuse –> etiology? (2)

A
  • TB or non-TB mycobact

- RA

143
Q

TB –> diffuse tenosynovitis –> classic imaging finding?

A

“rice bodies” –> discrete filling defects in fluid-filled sheaths

144
Q

RA –> distal radioulnar jt –> ruptures of extensor tendons 5, 4, 3, 2 –> dx?

A

Vaughan-Jackson synd

145
Q

flexor tendon –> tenosynovitis –> next step? why?

A

can spread rapidly to common flexors of wrist –> surg emergency –> call provider/go to OR

146
Q

De Quervain’s tenosynovitis –> involves which extensor compt?

A

1st extensor compt

147
Q

wrist –> 1st extensor compt –> comprised of what struct? (2)

A
  • ext pollicis brevis

- abductor pollicis longus

148
Q

intersection synd –> epidermiology?

A

rower

149
Q

wrist –> intersection synd –> involves which extensor compt?

A

2nd extensor compt

150
Q

2nd extensor compt –> comprised of what struct? (2)

A

ext carpi radialis brevis & longus

151
Q

wrist –> 3rd extensor compt –> tenosynovitis –> epidemiology?

A

drummer

152
Q

3rd extensor compt –>comprised of what struct? (1)

A

ext pollicus longus