Musculoskeletal - Skin - Connective Tissue_1 Flashcards
1
Q
What are the epidermis layers from surface to base?
A
Stratum Corneum (keratin • Stratum Lucidum • Stratum Granulosum • Stratum Spinosum • Stratum Basale
2
Q
what are the spines in the stratum spinosum?
A
desmosomes
3
Q
which epidermal layer is the stem cell site?
A
Stratum Basale
4
Q
what are the 3 epidermal appendages?
A
Sebaceous gland • Eccrine gland • Apocrine gland
5
Q
mechanism of sebaceous gland secretion?
A
holocrine secretion of sebum
6
Q
sebaceous gland associated with what?
A
hair follicle
7
Q
eccrine gland secretes what?
A
sweat
8
Q
eccrine glands are found where?
A
throughout the body • Eccrine glands are every where
9
Q
apocrine glands secrete what?
A
milky viscous fluid
10
Q
apocrine glands are found where?
A
axillae, genitalia, areolae
11
Q
when are apocrine glands functional?
A
do not become functional until puberty
12
Q
why are apocrine glands malodorous?
A
because of bacterial action
13
Q
functions of tight junctions?
A
zona occludens: • prevents paracellular movement of solutes
14
Q
tight junctions are composed of what?
A
claudins and occludins
15
Q
where are adherens junctions?
A
zonula adherins: below tight junctions
16
Q
adherens junctions form what?
A
belt connecting actin cytoskeletons of adjacent cells with Cadherins
17
Q
what are Cadherins?
A
Ca++ dependent adhesion proteins
18
Q
loss of E-cadherin does what?
A
promotes metastasis
19
Q
what is the function of desmosomes?
A
structural support via keratin interactions
20
Q
atoantibodies to desmosomes cause what?
A
pemphigus vulgaris
21
Q
components of desmosomes?
A
keratin • desmoplakin
22
Q
what happens in gap junctions?
A
channel proteins called connexons permit electrical and chemical communication between cells
23
Q
function of a hemidesmosome?
A
connects keratin in basal cells to underlying basement membrane
24
Q
autoantibodies to hemidesmosomes cause what?
A
bullous pemphigoid
25
what are integrins?
membrane proteins that maintain integrity of basement membrane by binding to laminin in BM
26
how does unhappy triad happen?
common injury in contact sportsL lateral force applied to a planted leg
27
unhappy triad includes which injuries?
tear of ACL, MCL and meniscus (classically medial, but lateral more common)
28
treatment for unhappy triad?
often requires surgical reconstruction
29
A and P in ACL and PCL refer to what?
sites of tibial attachment
30
positive anterior drawer test means what?
ACL tear
31
abnormal passive abduction at the knee means what?
MCL tear
32
what is the important landmark for pudendal nerve block?
ischial spine
33
what is the important landmark in finding the appendix?
2/3 of the way from the umbilicus to the anterior superior iliac spine (McBurney's point)
34
what is the important landmark in lumbar puncture?
iliac crest
35
what are the shoulder muscles that form the rotator cuff?
Supraspinatus • Infraspinatus • teres minor • Subscapularis • SItS (small t is for teres minor)
36
what is the most common rotator cuff injury?
Supraspinatus
37
action of supraspinatus?
abducts arm initially (before deltoid)
38
which rotator cuff muscle is a common pitching injury?
Infraspinatus
39
action of infraspinatus?
laterally rotates arm
40
action of teres minor?
adducts and laterally rotates arm
41
action of subscapularis?
medially rotates and adducts arm
42
rotator cuff muscles are innervated by what?
C5-C6
43
what are the bones of the wrist?
Scaphoid • Lunate • Triquetrum • Pisiform • Trapezium • Trapezoid • Capitate • Hamate • Some Lovers Try Positions That They Can't Handle
44
what is the most commonly fractured carpal bone?
scaphoid
45
scaphoid is prone to which complication?
avascular necrosis owing to retrograde blood supply
46
dislocation of which wrist bone may cause acute carpal tunnel syndrome?
lunate
47
what is carpal tunnel syndrome?
entrapment of median nerve in carpal tunnel
48
what is the pathogenesis of carpal tunnel syndrome?
nerve compression → paresthesia, pain, and numbness in distribution of median nerve
49
cause of lesion in upper trunk of brachial plexus?
trauma
50
cause of lesion in C7 root of brachial plexus?
compressed by cervical disk lesion
51
cause of lesion in axillary nerve?
fracture of surgical neck of humerus • dislocation of humerus • intramuscular injections
52
cause of lesion to lower trunk of brachial plexus?
compressed by cervical rib or by pancoast tumor of lung
53
lesion of lower trunk of brachial plexus leads to what?
Klumpke's palsy
54
cause of lesion to radial nerve in spiral groove?
lesioned by midshaft fracture of the humerus
55
cause of radial nerve compression in the axilla?
incorrect use of a crutch
56
cause of lesion in proximal median nerve?
compressed by supracondylar fracture of humerus • pronator teres syndrome
57
cause of lesion to deep branch of radial nerve?
stretched by subluxation of radius
58
cause of proximal ulnar nerve lesion?
lesioned by repeat minor trauma • fracture of medial epicondyle of humerus
59
caused of lesion to anterior interosseous nerve?
compressed in deep forearm
60
cause of lesion in distal median nerve?
compressed in carpal tunnel syndrome and by dislocated lunate
61
cause of distal ulnar nerve lesion?
lesioned by trauma to heel of the hand • fracture of hook of hamate
62
cause of lesion to recurrent branch of median nerve?
lesioned by superficial laceration
63
nerve root of top of shoulder dermatome?
C4
64
nerve root of lateral humerus dermatome?
C5
65
nerve root of medial arm → lateral forearm→ thumb and index finger dermatome?
C6
66
nerve root of middle finger and middle palm dermatome?
C7
67
Nerve root of ring/little finger and medial palm dermatome?
C8
68
Nerve root of medial forearm and distal medial arm dermatome?
T1
69
nerve root of medial proximal arm and inferior shoulder dermatome?
T2
70
cutaneous sensory nerve distribution on hand of the ulnar nerve?
little + 1/2 ring finger on palmar and dorsal surface of hand
71
cutaneous sensory nerve distribution on hand of median nerve?
thumb → half of ring finger on palmar surface • inner half of thumb, distal half of index to 1/2 ring finger on doral surface
72
cutaneous sensory nerve distribution on hand of radial nerve?
proximal edge of palmar thenar eminence on palmar and whole dorsum of thenar eminence
73
lesion to long thoracic nerve causes what?
winged scapula
74
lesion to upper trunk of the brachial plexus causes what?
Waiter's tip (Erbs palsy)
75
lesion to lower trunk of brachial plexus causes what?
Claw hand (Klumpke palsy)
76
lesion to posterior cord of the brachial plexus causes what?
wrist drop
77
damage to the axillary branch of the brachial plexus causes what?
deltoid paralysis
78
damage to radial branch of the brachial plexus causes what?
Saturday night palsy (wrist drop)
79
damage to musculocutaneous branch of brachial plexus causes what?
Difficulty flexing elbow, variable sensory loss
80
damage to the median branch of the brachial plexus causes what?
decreased thumb function (pope's blessing)
81
damage to the ulnar branch of the brachial plexus causes what?
intrinsic muscles of the hand, claw hand
82
roots that contribute to the long thoracic nerve?
C5, 6, 7
83
roots that contribute to upper trunk of the brachial plexus?
C5-6
84
roots that give rise to middle trunk of brachial plexus?
C7
85
roots that give rise to lower trunk of brachial plexus?
C8-T1
86
how many divisions in the brachial plexus?
6
87
trunks that contribute to the lateral cord of the brachial plexus?
upper • middle
88
trunks that give rise to posterior cord of the brachial plexus?
upper • middle • lower
89
trunks that give rise to medial cord of the brachial plexus?
lower
90
nerve roots that give rise to lateral cord of brachial plexus?
C5, 6, 7
91
nerve roots that give rise to posterior cord of brachial plexus?
C5, 6, 7, 8, T1,
92
nerve roots that give rise to medial cord of brachial plexus?
C8, T1
93
trunks that give rise to axillary branch of brachial plexus?
upper • middle • lower
94
trunks that give rise to radial branch of brachial plexus?
upper • middle • lower
95
trunks that give rise to musculocutaneous branch of brachial plexus?
upper • middle
96
trunks that give rise to median branch of brachial plexus?
upper • middle • lower
97
trunks that give rise to ulnar branch of brachial plexus?
lower
98
cords of brachial plexus that innervate flexors of forearm?
lateral • medial
99
cords of brachial plexus that innervates extensors of forearm?
posterior
100
nerve roots that contribute to axillary nerve?
C5-C6
101
nerve roots that contribute to radial nerve?
C5-T1
102
nerve roots that contribute to musculocutaneous nerve?
C5-C7
103
nerve roots that contribute to median nerve?
C5-T1
104
nerve roots that contribute to ulnar nerve?
C8-T1
105
brachial plexus is protected from clavicle fracture by what?
subclavius muscle
106
typically injury of axillary nerve?
fractured surgical neck of humerus • dislocation of humeral head
107
motor deficit in axillary nerve injury?
Deltoid- arm abduction at shoulder
108
sensory deficit in axillary nerve injury?
over deltoid muscle
109
sign associated with axillary nerve injury?
atrophied deltoid
110
what is the typical injury of the radial nerve?
fracture at midshaft of humerus • extended compression of axilla by back of chair or crutches
111
motor deficit seen in radial nerve injury?
BEST extensors • Brachioradialis • Extensors of wrist and fingers • Supinator • Triceps
112
sensory deficit seen in radial nerve injury?
posterior arm and dorsal hand and thumb
113
sign seen in radial nerve injury?
wrist drop
114
typical injury to the median nerve?
fracture of supracondylar humerus
115
motor deficit in proximal lesion to median nerve?
opposition of thumb • lateral finger flexion • wrist flexion
116
sensory deficit in proximal lesion to median nerve?
dorsal and palmar aspects of lateral 3 1/2 fingers • thenar eminence
117
sign seen in median nerve lesion?
ape hand • popes blessing
118
typical injury to ulnar nerve?
fracture of medial epicondyle of humerus • funny bone
119
motor deficit in proximal ulnar nerve injury?
medial finger flexion • wrist flexion
120
sensory deficit in proximal ulnar nerve lesion?
medial 1 1/2 fingers • hypothenar eminence
121
sign seen in proximal ulnar nerve lesion?
radial deviation of wrist upon wrist flexion
122
typical injury to musculocutaneous nerve?
upper trunk compression
123
motor deficit in musculocutaneous nerve injury?
biceps • brachialis • coracobrachialis • flexion of forearm at elbow
124
sensory deficit in musculocutaneous nerve injury?
lateral forearm
125
what causes erb-duchenne palsy 'waiters tip'?
traction or tear of the upper trunk of the brachial plexus (C5-C6)
126
erb duchenne palsy 'waiters tip' seen in who?
infants following trauma during delivery
127
findings in erb-duchenne palsy 'waiters tip'?
limb hangs by side (paralysis of abductors) • medially rotated (paralysis of lateral rotators) • forearm is pronated ( loss of biceps)
128
what are the causes of Klumpke palsy and thoracic outlet syndrome?
an embryologic or childbirth defect affecting inferior trunk of brachial plexus (C8-T1) • cervical rib can compress subclavian artery and inferior trunk, resulting in thoracic outlet syndrome
129
findings in klumpke palsy/thoracic outlet syndrome?
atrophy of thenar and hypothenar eminences • atrophy of interosseous muscles • sensory deficits on the medial side of the forearm and hand • disappearance of the radial pulse upon moving the head toward the ipsilateral side
130
clawing of the hand is conceptualized how?
as loss of the lumbricals, which flex the MCP joints and extend both the DIP and PIP joints
131
ulnar claw can be caused by what?
long-standing injury to ulnar nerve at hook of hamate (falling onto outstretched hand)
132
pathogenesis of ulnar claw?
distal ulnar nerve lesion → loss of medial lumbrical function→ inability to extend 4th and 5th digits when trying to open hand
133
median claw can be caused by what?
carpal tunnel syndrome or dislocated lunate
134
pathogenesis of median claw?
distal (after branches containing C5-C7 branches off to feed forearm flexors) median nerve lesion→ loss of lateral lumbrical function→ 2nd and 3rd digit are clawed upon attempted finger extension
135
what causes pope's blessing?
proximal median nerve lesion causes loss of lateral finger extension and thumb opposition
136
finding in pope's blessing?
when asked to make a fist, 2nd and 3rd digits remain extended and thumb remains unopposed, which looks like the hand of benediction
137
pathogenesis of ape hand?
proximal median nerve lesion → loss of opponens pollicus muscle function → unopposable thumb
138
pathogenesis of klumpke's total claw?
lesion of lower trunk (C8-T1) of brachial plexus → loss of function of all lumbricals; • forearm finger flexors (fed by part of median nerve with C5-C7) and finger extensors (fed by radial nerve) are unopposed→ clawing of all digits
139
muscle innervated by LTN?
serratus anterior
140
action of serratus anterior?
anchors scapula to thoracic cage • used for abduction above horizontal position
141
LTN can be injured how?
mastectomy
142
what happens when LTN is injured in mastectomy?
winged scapula and ipsilateral lymphedema
143
what innervates the muscles of the thenar eminence?
median
144
what innervates the muscles of the hypothenar eminence?
ulnar
145
what are the muscles in the thenar eminence?
Opponens pollicus • Abductor pollicus brevis • Flexor pollicus brevis
146
what are the muscles in the hypothenar eminence?
opponens digiti minimi • abductor digiti minimi • flexor digiti minimi
147
function of the dorsal interosseous muscles?
abduct the fingers
148
action of the palmar interosseous muscles?
adduct the fingers
149
action of the lumbrical muscles?
flex at the MCP joint • extend PIP and DIP joints
150
roots of obturator nerve?
L2-L4
151
roots of femoral nerve?
L2-L4
152
roots of common peroneal nerve?
L4-S2
153
roots of tibial nerve?
L4-S3
154
roots of superior gluteal nerve?
L4-S1
155
roots of inferior gluteal nerve?
L5-S2
156
cause of injury to obturator nerve?
anterior hip dislocation
157
motor defect in obturator nerve injury?
thigh adduction
158
sensory deficit in obturator nerve injury?
medial thigh
159
cause of injury to femoral nerve?
pelvic fracture
160
motor deficit in femoral nerve injury?
thigh flexion and leg extension
161
sensory deficit in femoral nerve injury?
anterior thigh and medial leg
162
cause of injury to common peroneal nerve?
trauma or • compression of lateral aspect of leg or • fibula neck fracture
163
motor deficit in common peroneal nerve injury?
foot eversion and dorsiflexion; • toe extension; • foot drop, foot slap, steppage gait
164
sensory deficit in common peroneal nerve injury?
anterolateral leg and dorsal aspect of foot
165
what is the cause of injury to tibial nerve?
knee trauma
166
what is the motor deficit in tibial nerve injury?
foot inversion and plantarflexion; • toe flexion
167
what is the sensory deficit in tibial nerve injury?
sole of foot
168
cause of injury to superior gluteal nerve?
posterior hip dislocation or polio
169
motor deficit in superior gluteal nerve lesion?
thigh abduction (positive trendelenberg sign)
170
cause of injury to inferior gluteal nerve?
posterior hip dislocation
171
motor deficit in inferior gluteal nerve injury?
cant jump, climb stairs, or rise from seated position • can't push inferiorly
172
mnemonic for common peroneal nerve?
PED= Peroneal Everts and Dorsiflexes; if injured, foot dropPED
173
mnemonic for Tibial Nerve?
TIP= Tibial Inverts and Plantarflexes; if injured, can't stand on TIPtoes
174
root of sciatic nerve?
L4-S3
175
course of sciatic nerve?
posterior thigh,splits into common peroneal and tibial nerve
176
6 steps in muscle excitation/ contraction?
1. AP depolarization opens presynaptic VG-Ca channels→ NT release • 2. postsynaptic ligand binding → muscle cell depolarization in motor end plate • 3. depolarization travels along muscle cell + down T tubule • 4. depolarization of VS-DHPR, mechanically coupled to ryanodine receptor on SR→ conformational change → Ca release from SR • 5. released Ca binds to troponin C → conformational change that moves tropomyosin out of myosin binding groove on actin filaments • 6. myosin releases bound ADP and is displaced on the actin filament (powerstroke). contraction → shortening of H and I bands and between Z lines (HIZ shrinkage), but the A band remains the same length
177
which band of sarcomere is always same length in contraction?
A band
178
which bands shrink during muscle contraction?
HIZ
179
what are the types of muscle fibers?
Type 1 muscle • Type 2 muscle
180
action of type 1 muscle?
slow twitch
181
;how do the morphologic features of type 1 muscle correspond to its action?
red fibers resulting from ↑ mitochondria and myoglobin concentration (↑OxPhos)→sustained contraction
182
action of Type 2 muscle?
fast twitch
183
morphology of type 2 muscle?
white fibers resulting from ↓ mitochondria (↑ anaerobic glycolysis)
184
weight training results in hypertrophy of which type of muscle?
type 2
185
4 biochemical changes that drive mechanical skeletal and cardiac muscle contraction?
1. Ca binds troponin C→ conformational change→displacement of tropomyosin and actin/myosin cycling • 2. Pi is released, changing myosin head conformation, causing power stroke • 3. ATP binds myosin head→ release from actin filament • 4. ATP hydrolysis cocks myosin head
186
4 states in mechanical skeletal muscle contraction?
1. cocked state • 2. cross bridged state • 3. power-stroke state • 4. released state
187
what does lack of ATP do to muscle contraction?
causes rigor mortis
188
what are the 2 types of bone formation?
endochondrial ossification • membranous ossification
189
where does endochondrial ossification take place?
bones of axial and appendicular skeleton • base of the skull
190
what happens in endochondrial ossification?
cartilaginous model of bone is first made by chondrocytes • osteoclasts and osteoblasts later replace with woven bone and then remodel to lamellar bone
191
in adults, woven bone occurs when?
after fractures • Paget's disease
192
where does membranous ossification take place?
bones of calvarium and facial bones
193
what happens in membranous ossification?
woven bone formed directly without cartilage • later remodelled to lamellar bone
194
action of osteoblasts?
build bone by secreting collagen and catalyzing mineralization
195
origin of osteoblasts?
differentiate from mesenchymal stem cells in periosteum
196
what are osteoclasts?
multinucleated cells that dissolve bone by secreting acid and collagenases
197
osteoclasts differentiate from what?
monocytes/macrophages
198
effects of PTH on bone at low, intermittent levels?
exerts anabolic effects (building bone) on osteoblasts and osteoclasts (indirect)
199
effects of chronic high PTH on bone?
catabolic effects (osteitis fibrosa cystica)
200
effect of estrogen on bones?
inhibits apoptosis in bone forming osteoblasts and induces apoptosis in bone resorbing osteoclasts
201
what happens to bone in estrogen deficiency (surgical or postmenopausal)?
excess remodeling cycles and bone resorption lead to osteoporosis
202
pathogenesis of achondroplasia?
failure of longitudinal bone growth (endochondral ossification)→ short limbs • membranous ossification is not affected → large head relative to limbs
203
molecular cause of achondroplasia?
constitutive activation of FGFR3 actually inhibits chondrocyte proliferation
204
inheritance of achondroplasia?
>85% of mutations occur sporadically and are associated with ↑ paternal age • also demonstrates AD inheritance
205
achondroplasia is a common cause of what?
dwarfism
206
prognosis of achondroplasia?
normal life span and fertility
207
what happens in osteroporosis?
trabecular (spongy) bone loses mass and interconnections despite normal bone mineralization and lab values (Ca and PO4)
208
osteoporosis can lead to what?
vertebral crush fractures- acute back pain, loss of height, kyphosis
209
what is type I osteoporosis?
post menopausal- ↑ bone resorption due to ↓ estrogen
210
injuries common to type I osteoporosis?
femoral neck fracture • distal radius (colles fracture)
211
what is type II osteoporosis?
senile osteoporosis- men and women >70yo
212
prophylaxis for type II osteoporosis?
regular weight bearing exercise and adequate calcium and VitD intake throughout adulthood
213
treatment for osteoporosis?
estrogen (SERMs) +/- calcitonin • bisphosphonates or pulsatile PTH for severe cases
214
what meds are CI in osteoporosis?
glucocorticoids
215
osteopetrosis AKA?
marble bone disease
216
pathogenesis of osteopetrosis?
failure of normal bone resorption due to defective osteoclasts → thickened, dense bones that are prone to fracture
217
hematologic complications of osteopetrosis?
bone fills marrow space → pancytopenia, extramedullary hematopoiesis
218
molecular cause of osteopetrosis?
mutations (carbonic anhydrase II) ↓ ability of osteoclast to generate acidic environment necessary for bone resorption
219
Xray findings in osteopetrosis?
bone in bone appearance
220
osteopetrosis can result in what?
cranial nerve impingement and palsies as a result of narrowed foramina
221
tx for osteopetrosis?
BM transplant is potentially curative since osteoclasts are derived from monocytes
222
what causes osteomalacia/rickets?
vitamin D deficiency
223
pathogenesis of osteomalacia/rickets?
defective mineralization/calcification of osteoid→ soft bones that bow out
224
hormonal changes in osteomalacia/rickets?
↓ VitD→ ↓ serum Ca → ↑ PTH secretion → ↓ serum PO4
225
result of hyperactive osteoblasts in osteomalacia/rickets?
↑ ALP (osteoblasts require alkaline environment)
226
Paget's disease of bone AKA?
osteitis deformans
227
what is Paget's disease of bone?
common, localized disorder of bone remodeling caused by ↑ in both osteoblastic and osteoclastic activity
228
lab values in pagets disease of bone?
serum Ca, PO4, PTH= NL • ↑ ALP
229
findings in pagets disease of bone?
mosaic woven bone pattern • long bone chalk stick fractures • hat size ↑ • hearing loss due to auditory foramen narrowing
230
CV complication of pagets disease of bone?
↑ blood flow from ↑ arteriovenous shunts may cause high output cardiac failure
231
pagets disease of bone carries ↑ risk of what?
osteogenic sarcoma
232
lab values in osteoporosis?
↓ bone mass with normal Ca, PO4, ALP, PTH
233
lab values in osteopetrosis?
thickened dense bones with • ↓ Ca • ↑ ALP • normal PO4 and PTH
234
lab values in osteomalacia/rickets?
soft bones with • ↓ Ca and PO4 • ↑ ALP and PTH
235
lab values in osteitis fibrosa cystica?
brown tumors of hyperparathyroidism • ↓ PO4 • ↑ Ca, ALP, PTH
236
lab findings in paget's disease of bone?
abnormal bone architecture with • ↑ ALP • normal Ca, PO4, PTH
237
what happens in polyostotic fibrous dysplasia?
bone is replaced by fibroblasts, collagen, and irregular bony trabeculae
238
what is McCune-Albright syndrome?
form of polyostotic fibrous dysplasia characterized by multiple unilateral bone lesions associated with endocrine abnormalities (precocious puberty) and cafe au lait spots
239
what are the benign primary bone tumors?
1. giant cell tumor (osteoclastoma) • 2. osteochondroma (exostosis)
240
epidemiology/location of Giant cell tumor/osteoclastoma?
20-40yo • epiphyseal end of long bones
241
presentation of giant cell tumor/osteoclastoma?
locally aggressive benign tumor often around the distal femur, proximal tibial region
242
Xray appearance of giant cell tumor/osteoclastoma?
double bubble or soap bubble appearance
243
histopathology in giant cell tumor/osteoclastoma?
spindle shaped cells with multinucleated giant cells
244
what is the most common benign primary bone tumor?
osteochondroma (exostosis)
245
epidemiology of osteochondroma?
males <25yo
246
characteristics of osteochondroma?
1. mature bone with cartilaginous cap • 2. commonly originates from long metaphysis • 3. malignant transformation to chondrosarcoma is rare
247
what are the malignant primary bone tumors?
osteosarcoma • ewings sarcoma • chondrosarcoma
248
what is the 2nd most common primary malignant bone tumor?
osteosarcoma (1st is multiple myeloma)
249
epidemiology of osteosarcoma?
M>F • 10-20yo 1°
250
what are the predisposing factors for osteosarcoma?
pagets disease of bone • bone infarcts • radiation • familial retinoblastoma
251
location of osteosarcoma?
metaphysis of long bones, often around distal femur, proximal tibial region
252
xray findings in osteosarcoma?
codman's triangle (from elevation of periosteum) or sunburst patten
253
prognosis of osteosarcoma?
aggressive
254
tx for osteosarcoma?
surgical en bloc resection (with limb salvage) and chemotherapy
255
epidemiology of ewings sarcoma?
boys <15yo
256
ewings sarcoma commonly appears where?
in diaphysis of long bones, pelvis, scapula, ribs
257
severity of ewings sarcoma?
extremely aggressive with early metastases, but responsive to chemotherapy
258
histopathology of ewings sarcoma?
anaplastic small blue cell malignant tumor • onion skin appearance in bone • 'going out for ewings and onion rings'
259
genetic cause of ewings sarcoma?
t(11;22) • 11+22=33 patrick ewings jersey number
260
epidemiology of chondrosarcoma?
men 30-60yo
261
location of chondrosarcoma?
usually located in pelvis, spine, scapula, humerus, tibia, or femur
262
what type of cancer is chondrosarcoma?
malignant cartilaginous tumor
263
where does chondrosarcoma come from?
may be of primary origin or from osteochondroma
264
histopathology of chondrosarcoma?
expansile glistening mass within the medullary cavity
265
epihphyseal bone tumor?
giant cell tumor (soap bubble)
266
metaphyseal bone tumor?
benign= osteochondroma -exostosis • malignant= osteosarcoma- codmans triangle
267
diaphyseal bone tumor?
malignant: • ewings sarcoma • chondrosarcoms
268
etiology of osteoarthritis?
mechanical- joint wear and tear destroys articular cartilage
269
etiology of RA?
autoimmune- inflammatory destruction of synovial joints • type III HSR
270
joint findings in osteoarthritis?
subchondral cysts • sclerosis • osteophytes (bone spurs) • eburnation (polished, ivory like appearance of bone) • Heberden's nodes (DIP) • Bouchard's nodes (PIP) • no MCP involvement
271
joint findings in RA?
pannus formation in joints (MCP, PIP) • subcutaneous rheumatoid nodules • ulnar deviation of fingers • subluxation • Baker's cysts • no DIP involvement
272
pathology in subcutaneous rheumatoid nodules in RA?
fibrinoid necrosis
273
location of Baker's cysts in RA?
popliteal fossa
274
predisposing factors for OA?
age • obesity • joint deformity
275
predisposing factors for RA?
F>M • 80% RF (+) • anti-cyclic citrullinated peptide antibody is more specific • strong association with HLA-DR4
276
classic presentation of OA?
pain in weight bearing joints after use (EOD) improving with rest • knee cartilage loss medially (bowlegged) • noninflammatory • no systemic symptoms
277
classic presentation of RA?
morning stiffness > 30min improving with use • symmetric joint involvement • systemic symptoms
278
systemic symptoms of RA?
fever • fatigue • pleuritis • pericarditis
279
Tx for OA?
NSAIDs • intra-articular glucocorticoids
280
Tx for RA?
NSAIDs • glucocorticoids • disease modifying agents (MTX, sulfasalazine, TNF-α inhibitors)
281
what happens in Sjogrens syndrome?
lymphocytic infiltration of exocrine glands, especially lacrimal and salivary
282
classic triad of sjogrens syndrome?
xerophthalmia (dry eyes, conjunctivitis) • xerostomia (dry mouth, dysphagia) • arthritis
283
sjogrens causes what complications?
parotid enlargement • ↑ risk of B cell lymphoma • dental caries
284
markers present in sjogrens syndrome?
autoantibodies to ribonucleoprotein antigens: SS-A (Ro), SS-B (La)
285
sjogrens predominantly affects who?
females 40-60yo
286
sjogrens associarted with what?
RA
287
what are the findings in gout?
precipitation of monosodium urate crystals into joints due to hyperuricemia
288
hyperuricemia that causes gout can be caused by what?
lesch-nyhan syndrome • PRPP excess • ↓ excretion of uric acid (thiazides) • ↑ cell turnover • von gierkes disease
289
percentage of gout due to underexcretion?
90%
290
percentage of gout due to overproduction?
10%
291
features of crystals in gout?
needle shaped and negatively birefringent = yellow crystals under parallel light
292
gout is more common in who?
men
293
symptoms of gout?
asymmetric joint distribution • joint is swollen, red and painful • painful MTP joint of the big toe (podagra) • tophus formation
294
common location of tophus formation in gout?
external ear • olecranon bursa • Achilles tendon
295
acute attack of gout tends to occur when?
after large meal or alcohol consumption
296
why does alcohol precipitate a gout attack?
alcohol metabolites compete for same excretion sites in kidney as uric acid, causing ↓ uric acid secretion and subsequent build up in blood
297
treatment for acute gout?
NSAIDs (indomethacin) • glucocorticoids
298
treatment for chronic gout?
xanthine oxidase inhibitors (allopurinol, febuxostat)
299
pseudogout is caused by what?
deposition of calcium pyrophosphate crystals within the joint space
300
pseudogout forms crystals with which features?
basophilic, rhomboid crystals that are weakly positively birefringent
301
typical location of pseudogout?
usually affects large joints (classically the knee)
302
pseudogout affects who?
>50yo, M=F
303
treatment for pseudogout?
NSAIDs for sudden severe attacks • steroids • colchicine
304
difference between gout and pseudogout crystals under parallel light?
gout= yellow • pseudogout=blue
305
what are the common causes of infectious arthritis?
S aureus • Streptococcus • Neisseria gonorrhea
306
what is gonococcal arthritis?
STD that presents with migratory arthritis with asymmetric pattern
307
presentation of gonococcal arthritis?
affected joint is swollen, red and painful • STD= Synovitis (knee), Tenosynovitis (hand), Dermatitis (pustules)
308
cause of osteonecrosis (avascular necrosis)?
infarction of bone and marrow
309
symptoms of osteonecrosis?
pain associated with activity
310
osteonecrosis is caused by what?
trauma • high dose corticosteroids • alcoholism • SCD
311
most common site of osteonecrosis?
femoral head
312
what are the seronegative spondyloarthropathies?
PAIR • Psoriatic arthritis • Ankylosing spondylitis • Inflammatory bowel disease • Reactive arthritis
313
what are seronegative spondyloarthropathies?
arthritis without rheumatoid factor ( no anti-IgG antibody)
314
seronegative spondyloarthropathies have strong association with what?
HLA-B27 (gene that codes for HLA MHC class II)
315
sernegative spondyloarthropathies occur more often in who?
males
316
what is psoriatic arthritis?
joint pain and stiffness associated with psoriasis
317
how does psoriatic arthritis present?
asymmetric and patchy involvement • dactylitis (sausage fingers) • pencil in cup deformity on xray
318
frequency of psoriatic arthritis?
seen in fewer than 1/3 of patients with psoriasis
319
pathogenesis of ankylosing spondylitis?
chronic inflammatory disease of spine and sacroiliac joints→ ankylosis (stiff spine due to fusion of joints), uveitis, and aortic regurgitation
320
common presentation of ankylosing spondylitis?
bamboo spine (vertebral fusion)
321
why is IBS considered a seronegative spondyloarthropathy?
Crohns and UC are often accompanied by ankylosing spondylitis or peripheral arthritis
322
classic triad in reactive arthritis (reiters syndrome)?
conjunctivitis and anterior uveitis • urethritis • arthritis • can't see can't pee can't climb a tree
323
when does reiters syndrome occur?
post GI or chlamydia infection
324
epidemiology of SLE?
90% are female 14-45yo
325
SLE most common and most severe in who?
black females
326
presentation of SLE can include what?
fever • fatigue • weight loss • Libmann-Sacks endocarditis • hilar adenopathy • Raynauds phenomenon
327
what is libmann sacks endocarditis?
verrucous, wart like, sterile vegetations on both sides of valve
328
what is the common cause of death in SLE?
nephritis
329
what type of nephritis causes death in SLE?
DPGN if nephritic • MGN if nephrotic
330
SLE pts test false positive for what?
syphilis RPR/VDRL due to antiphospholipid antibodies, which cross react with cardiolipin used in tests
331
Lab tests for SLE detect the presence of what?
ANA • Anti-dsDNA • anti-Sm • antihistone Ab
332
use of ANA test for SLE?
sensitive (primary screening) but not specific for SLE
333
use of anti-dsDNA test for SLE?
very specific, poor prognosis
334
use of anti-Sm test for SLE?
very specific, but not prognostic
335
use of antihistone test for SLE?
more sensitive for drug induced lupus
336
mnemonic for SLE?
I'M DAMN SHARP • Immunoglobulins (anti-dsDNA, anti-Sm, antiphospholipid) • Malar rash • Discoid rash • Antinuclear antibody • Mucositis • Neurologic disorders • Serositis • Hematologic disorders • Arthritis • Renal disorders • Photosensitivity
337
sarcoidosis is characterized by what?
immune-mediated, widespread noncaseating granulomas and elevated serum ACE levels
338
sarcoidosis is common in who?
black females
339
typical presentation of sarcoidosis?
often asymptomatic except for enlarged lymph node. incidental findings on CXR of bilateral hilar adenopathy or reticular opacities
340
sarcoidosis is associated with what?
restrictive lung disease (interstitial fibrosis) • erythema nodosum • bells palsy • epithelial granulomas containing microscopic Schaumann and asteroid bodies • uveitis • hypercalcemia
341
what causes hypercalcemia in sarcoidosis?
elevated 1α-hydroxylase-mediated vitD activation in epitheloid macrophages
342
what is the treatment for sarcoidosis?
steroids
343
what are the symptoms of polymyalgia rheumatica?
pain and stiffness in shoulders and hips, often with fever, malaise, and weight loss • does not cause muscular weakness
344
polymyalgia rheumatica is more common in who?
women >50yo
345
polymyalgia rheumatica is associated with what?
temporal (giant cell) arteritis
346
findings in polymyalgia rheumatica?
↑ ESR • normal CK
347
treatment for polymyalgia rheumatica?
rapid response to low dose corticosteroids
348
fibromyalgia is most commonly seen in who?
women 20-50yo
349
presentation of fibromyalgia?
chronic widespread musculoskeletal pain associated with stiffness, paresthesia, poor sleep, and fatigue
350
what is polymyositis?
progressive symmetrical proximal muscle weakness, characterized by endomysial inflammation with CD8+ T cells
351
polymyositis most often involves which location?
shoulders
