Muscle / Skin Flashcards
1
Q
Where do ACL and PCL attach?
A
ACL: anterior tibia
PCL: posterior tibia
2
Q
What is anterior drawer?
A
If ACL is busted, tibia moves freely anteriorly if you pull on it
3
Q
What are varus and valgus force testing?
A
Varus: medially directed force on tibia, Testing LCL
Valgus: laterally directed force on tibia, testing MCL, if torn, will ABduct
- Think if the ligaments as a hinge, if one is broken it allows it to swing open like a door in direction of pressure away from tear
4
Q
What is meniscus?
A
Cartilage between tibia and femur: medially it is attached to MCL making it less mobile
5
Q
How to test for meniscal tear?
A
Mcmurray test: rotation of tibia when knee at 90
- Pain on internal rotation (toes to midline): lateral meniscal tear
- Pain in external rotation: medial meniscal tear
6
Q
What is the unhappy triad?
A
Traumatic injury to lateral knee causing:
- MCL
- ACL
- Lateral meniscus “LAME” LAteral MEniscus
7
Q
What is housemaid’s knee?
A
“Prepatellar bursitis”
- Too much kneeling = swollen / painful bursa of patella
8
Q
What is a baker’s cyst?
A
- Cystic lesion in knee pit area
- Can cause DVT if large enough
9
Q
Muscles in the rotator cuff? Functions?
A
“SITS”
Supraspinatus: First 15 ABduction (deltoid after)
Infraspinatus: Lateral rotation of arm
Teres minor: ADduction / lateral rotation
Subscapularis: Medial rotation / ADduction
10
Q
What is injury if cant abduct arm, but if you place on cheir or give it a boost then you can?
A
Tear in supraspinatus as this is responsible for first 15 degrees of lifting then the deltoid takes over
11
Q
What muscle provides the following arm motion:
First 15 ABduction (deltoid after)
A
Supraspinatus
12
Q
What muscle provides the following arm motion:
Lateral rotation of arm
A
Infraspinatus
13
Q
What muscle provides the following arm motion:
ADduction / lateral rotation
A
Teres minor
14
Q
What muscle provides the following arm motion:
Medial rotation / ADduction
A
Subscapularis
15
Q
Cause of medial epicondylitis?
A
- Golf
2. Pitching
16
Q
What causes lateral epicondylitis?
A
- Tennis elbow: from backhand motion
17
Q
Bone injured when pain on snuffbox pressure?
A
Scaffoid
18
Q
Dislocation of what bone can cause carpal tunnel?
A
Lunate can lead to median nerve compression
19
Q
What happened if ulnar injury after fall on outstretched hand?
A
Hamate bone injury: think, you fell on your outstretched arm because you were trying to “Ham it up”
20
Q
Where is carpal tunnel numbness experienced?
A
- Thumb
- First finger
- Middle finger
- half of ring finer
21
Q
3 associations of carpal tunnel?
A
- Pregnancy
- RA
- HYPOthyroid
22
Q
What is guyon canal syndrome and what causes?
A
- Injury to ulnar nerve from leaning on palm
23
Q
Nerve roots of brachial plexus?
A
C5 - T1
24
Q
Where does C8 nerve come out?
A
Below C7, all other cervical nerves come out above their respective vertebrae
25
What does posterior cord lesion cause?
Problem with extension as it splits into axial and radial nerve
26
Dermatomes of hand?
C6 - 8 as you move from thumb to pinky
| - Middle finger is C7 only
27
Sensory innervation of palm?
Ulnar: pinky and half of third finger
| Median nerve: thumb and 2.5 fingers
28
Sensory innervation of dorsal hand?
Ulnar: pinky / half of third finger (same as palmar surface)
Median: tips of thumb and 2.5 fingers
Radial: lower portion thumb and 2.5 fingers down to wrist
29
What is saturday night palsy?
- Fall asleep with arm over chair compressing radial nerve leading to wrist drop and numbness
30
Another name for radial never?
Great extensor
31
Where is radial nerve often compressed?
Spiral groove of humerus in the axilla
| - Can be caused with arm over chair or use of crutches
32
What would direct trauma to tip of shoulder cause?
Upper trunk injury: "Herbs / waiter's palsy"
- Deltoids, biceps, brachialis paralyzed
- Arm hangs down and medially rotated
- No elbow flexion / supination
33
Cause of lower trunk injury?
1. Grabbing branch on fall
2. Pulling babies arm in labor
3. Pancoast tumor of lung
4. Additional cervical rib
* Leads to monkeys grip
34
Where is proximal radial nerve located?
Axilla
35
When does radially nerve move radially?
Just past elbow
36
Injury in elbow dislocation?
Deep branch radial nerve: loss of innervation of extensor wrist muscles: wrist drop
37
Route of axillary nerve?
Hugs surgical neck of humerus?
38
What nerve hugs surgical neck of humerus?
Axillary
39
Nerve in spiral groove of humerus?
Radial
40
Nerve injured in fracture of humeral head?
Axillary
41
Nerve injury in anterior dislocation of humerus?
Axillary as wraps around humeral head
42
Injury if can abduct arm after 15 degrees?
Deltoid from anterior dislocation of shoulder injuring axially nerve
43
Nerve that innervates deltoid?
Axillary nerve
44
How would musculocutaneous nerve injured and what would signs be?
- Carrying heavy backpack: innervates brachioradialis so you can flex arm and will have numb patch of skin on forearm
45
What compressed if supracondylar fracture of humerus?
Median nerve
46
What does long thoracic innervated?
Serratus anterior: leads to winged scapula
47
Function of lumbricals?
1. Flex MCP joint
| 2. Extend DIP / PIP
48
What does distal lesion to median or ulnar nerve cause?
"Clawhand" flexion at DIP / PIP
| - Lumbrical extension of DIP / PIP is loss so flexors are exaggerated
49
What is ulnar claw?
- Distal ulnar injury = loss of function to medial lumbricals
= claw of 3/4th fingers
aka "pope's blessing sign "
50
Injury if try to make fist and thumb, 1/2 second fingers wont close?
Proximal medial nerve lesion
51
Injury if you can't extend first second fingers?
1. Distal median nerve lesion
52
Injury if can't close pinky and 4th finger?
Proximal ulnar nerve
53
Injury if you can't move thumb away from hand?
Opponens pollicis injury innervated by proximal medial nerve
54
Lesion causing total claw?
Lower trunk lesions C8 - T1 of brachial plexus
55
What is thenar eminence and muscles found in it?
Area of palm by thumb: "OAF"
1. Opponens pollicis
2. Abductor pollicis
3. Flexor pollicis brevis
* **All innervated by medial "million dollar" nerve
56
Nerve to hypothenar eminence?
Ulnar
| - OAF as in thenar eminence but this is digiti minimi instead of pollicis
57
What do dorsal / palmar interossei do?
"DAB / PAD"
Dorsal: ABduct
Palmar: ADduct
58
What gives rise to tibial and common peroneal nerves?
Tibial: Sciatic
Peroneal: Sciatic
59
What does obturator innervated?
- Medial thigh muscles: adduct thigh
| - Sensory innervation of medial thigh
60
What injury causes sensory loss of medial thigh and inability to ADduct thighs?
Obturator
61
Injury causing obturator injury?
Anterior hip dislocation
62
Injury caused by anterior hip dislocation?
Obturator injury causing medial thought sensory loss and inability to ADduct thighs
63
What does femoral nerve innervate?
Leg extensors of quad
1. Quads
2. Sartorius
3. Pectineus
64
How does femoral nerve injury present?
- Difficulty flexing and extending leg
| - Sensory deficit on anterior thigh / medial leg
65
Which nerve injured:
- Difficulty flexing and extending leg
- Sensory deficit on anterior thigh / medial leg
Femoral
66
How is femoral nerve injured?
Trauma / pelvic fracture
67
Nerve injury in pelvic fracture?
Femoral
68
Another name for common peroneal nerve?
Fibular (lateral bone)
69
Peroneal innervation?
- Lateral leg muscles: foot eversion
| - Dorsal flexion
70
Tibial innervation?
"TIP"
- Medial muscles: inversion of foot
- Plantar flexion
71
Cause of foot drop?
Common peroneal injury
72
Autoimmune disease that can cause foot drop?
MS
73
What would happen in constantly compression fibule by sleeping on park benches and such?
Fibular nerve injury
74
Function of superior gluteal nerve?
ABduction of thigh / stabilization of hip
- Trendelenburg sign seen if injured: opposite hip drops when standing on on leg as ipsilateral hip isn't strong enough to hold steady
75
When is trendelenburg sign seen?
- Injury to superior gluteal nerve
76
Where is lesion in hip drop?
Contralateral superior gluteal nerve
77
Injury in posterior hip dislocation?
Superior gluteal nerve: contralateral hip drop
| Inferior gluteal nerve:
78
Appearance of inferior gluteal nerve injury?
Gluteus maximus innervation: extensor of hip
- Trouble extending hip (pushing it downward), trouble:
1. Jumping
2. Climbing stairs
3. Rising from seated position
79
Function of glut max?
Hip extension: innervated by inf glut
80
Injury if having trouble:
1. Jumping
2. Climbing stairs
3. Rising from seated position
Inferior gluteal nerve supplying glut max
81
Root and innervation of pudendal?
S2 - 4 innervating perineum
82
How to find pudendal nerve?
Find ischial spine to inject anesthetic in childbirth
83
Symptoms if compression at L3 - 4?
1. Weak knee extension
| 2. Decrease patellar relfex
84
Where is lesion if:
1. Weak knee extension
2. Decrease patellar reflex
L3 - 4
85
Symptoms if compression at L4 - 5?
1. Week dorsiflexion / can't heel walk
86
Where is lesion if:
| 1. Week dorsiflexion / can't heel walk
L4 - 5
87
Symptoms if compression at L5 - S1?
1. Weak plantar flexion
2. Cant toe walk
3. Decrease achilles reflex
88
Where is lesion if:
1. Weak plantar flexion
2. Cant toe walk
3. Decrease achilles reflex
L5 - S1
89
Nerve and artery along axilla on thorax?
Nerve: long thoracic
Artery: Lateral thoracic artery
90
Nerve and artery in surgical head of humerus?
Nerve: Axillary
Artery: Posterior circumflex humeral
91
Nerve and artery in radial groove at midshaft of humerus?
Nerve: radial
Artery: deep brachial
92
Nerve and artery in cubital fossa?
Nerve: medial
| Artery brachial artery
93
What nerve runs with popliteal artery?
Tibial nerve
94
Artery with tibial nerve as wraps front of ankle?
Posterior tibial
95
What are DHP receptors?
"Dihydropyridine receptors"
| - Voltage gated Ca channels on surface of myocytes
96
What are ryanodine receptors?
Ca induced Ca channels on surface of SR in myocyte
97
What are myofibrils composed of?
Sarcomeres: smallest functional unit of muscle cells
98
Extent of sarcomere?
Sarcomeres extend from Z line to Z line
| "Z is end of sarcomere and the alphabet"
99
What comes off the Z lines?
Thin Actin molecules projecting in towards the M line
100
What are the lines coming off the M lines?
Thick Myosin molecules extending out to Z line
101
What is the H zone?
Stretch of myosin heavy chains not overlapping with actin light chain
102
What is the I band?
Part of actin light chains not overlapping my myosin heavy chains
103
When is H zone longest?
Relaxation
104
What is the A band?
Entire length of myosin heavy chain from end to end
* **Length DOES NOT change with contraction
- The light and heavy chain are simply sliding along each other
105
Which areas get smaller in contraction?
I band and H zone
106
Which areas elongate in relaxation?
I band and H zone
107
How do Z lines appear on EM?
Dark banks
108
What happens at motor end plate?
Depolarization via Na channels spreading down to T tubules causing DHP-r depolarization allowing Ca to flow in
- Ryanodine receptor on SR changes conformationally allowing Ca release into cytoplasm
109
Where does Ca bind once release from SR?
Troponin C: cause tropomyosin to move out of myosin binding groove on actin filament
110
What does myosin do when tropomyosin moves?
Releases ATP it was bound to allowing it to power stroke along actin
111
What is ATP necessary for?
Detachment of myosin head from actin filament
| - This is why you get rigormortis when dead: you can no longer make ATP so can no longer release myosin from actin
112
Which fibers stain dark and light?
Dark: Type I, sustained contraction
Light: type II, fast twitch, thing "2 fibers = 2x as fast"
113
What do type I fibers do?
```
"One Slow Red Ox"
Type I
Slow Twitch
Red Fibers
Need Oxidative phosphorylation
```
114
Which muscles tend to be slow twitch?
Postural
115
What type of muscle hypertrophies in weight training?
Type II: white, slow, glycolysis
116
What does Ca do when enters smooth muscle cell?
- Binds calmodulin instead of RYR or troponin C
- Calmodulin activates Myosin light chain kinase which phosphorylates myosin chains
- Phosphorylated myosin cross bridges along actin
- Myosin light chain phosphatase takes of P causing relaxation
117
What can cause relaxation in smooth muscle?
1. Myosin light chain phosphatase
| 2. NO from endothelial cells
118
How does NO cause SM relaxation?
1. NO activates guanylyl cyclase increasing cGMP
| 2. cGMP inhibits myosin light chain kinase
119
What bones are formed by endochondral ossification?
All the long bones in body
| - Cartilage remodeling is first step on which woven and lamellar bone is formed
120
What is membranous ossification?
- Woven bone directly formed with no cartilage base
| * *Occurs in skull and facial bones
121
What are osteocytes?
- Derived from osteoblasts
| - Regulate bone repair and remodeling
122
Progenitor of Osteoclasts?
Monocytes
123
What is histologic marker of osteoclasts?
TRAP stain - same stain used in hair cell leukemia
124
What is TRAP marker for?
Osteoclasts
125
Impact of estrogen on bone?
1. Prevents apoptosis of osteoblasts and osteocytes
2. Promotes osteoclast death
* Promotes bone formation
126
What is achondroplasia? Cause?
- Impaired cartilage proliferation in growth plate
- Impacts longs bones that grow via endochondral ossification
- Caused by activating mutation of FGFR3
127
What does activation mutation in FGFR3 cause?
Achondroplasia
128
Presentation of achondroplasia?
- Short extremities with normal head / chest
| - Cartilage needed in long bones but not in bones that grow via membranous ossification such as face and chest
129
What is osteogenesis imperfecta? Cause?
- Congenital defect in bone formation = weak bones
| - AD defect in type I collagen
130
What type of collagen is present in bone?
Type ONE
| - Think ONE as in "bONE"
131
Presentation of osteogenesis imperfecta?
1. Bone fractures
2. Blue sclera: exposure of choroidal veins
3. Hearing loss
* **Type I collagen is found in sclera and ears also
132
What is the following presentation indicative of:
1. Bone fractures
2. Blue sclera: exposure of choroidal veins
3. Hearing loss
Osteogenica imperfect
133
What is osteopetrosis?
"Petros" = "rock like"
| - Inherited defect in resorptive osteoclast activity = thick, heavy bone that fractures easily
134
Common cause of osteopetrosis?
Carbonic anhydrase deficiency
- Acid necessary to remove Ca and resorb bone
- Osteoclasts usually use CA to create this
135
Presentation of osteopetrosis?
1. Easy fractures in abnormally thick bone
2. Pancytopenia: marrow pushed out by bone
3. Vision / hearing impairment: skull compressing CN
4. Hydrocephalus: blocks foramen magnum
5. RTA: can't excrete acid / make bicarb in kidney
136
Treatment of osteopetrosis?
Bone marrow transplant: allows to you make normal monocytes which are progenitors of osteoclasts
137
Whats is rickets?
- Defective osteoid mineralization due to low Vitamin D `
138
What is osteomalacia?
Rickets in adults
139
What is osteoid?
Osteoblasts make osteoid which must be mineralized with Ca and P to make final bone
140
Rickets presentation?
1. Pigeon breast
2. Bow legs
3. Frontal bossing: osteoid deposition in skull
4. Rachitic rosary: osteoid deposition at CV junction
141
Lab values in osteomalacia?
1. Low Ca
2. Low P
3. Increased PTH
4. Increased Alk phos
142
What does alk phos do?
Released by osteoblasts to create alkaline environment that is necessary for Ca deposition
143
What is osteoporosis?
- Loss of trabecular bone mass = porous bone that easily fractures
144
What is risk of osteoporosis based on?
1. Peak bone mass
| 2. Rate of decline after peak
145
What determines peak bone mass?
1. Diet
2. Exercise
3. Vitamin D receptor you inherit
146
Osteoporosis presentation?
1. Pain in fractures in weight bearing areas
147
How is bone density measured?
Dexa scan
148
Serum levels in osteoporosis?
Everything is normal
149
Osteoporosis therapy?
1. Exercise
2. Vitamin D / Ca
3. Bisphosphonates
150
How do bisphosphonates work?
- Attaches to bone and osteoclasts eat it leading to their death
151
What is paget's disease of bone?
- Imbalance between osteoclasts and blasts
- Normally PTH signals blasts which activate clasts
- In paget's, this signalling goes awry = increase resorb
- Blasts try to catch up but lay down weak bone
* Result is thick sclerotic bone that easily fractures
152
Whaten is mosaic pattern of lamellar bone seen?
Paget's
153
Paget's presentation?
1. Increasing hat size
2. Bone pain
3. Hearing loss
4. Lion faces
5. Elevated alk phos
154
What is following indicative of:
1. Increasing hat size
2. Bone pain
3. Hearing loss
4. Lion faces
5. Elevated alk phos
Paget's
155
Paget's treatment?
1. Calcitonin
| 2. Bisphosphonates
156
Paget's complications?
1. High output cardiac failure
| 2. Osteosarcoma: malignant blast tumor
157
How does osteomyelitis occur?
Hematogenous bacterial spread
Kids: seeds metaphysis
Adults: seeds epiphysis
158
What are the epiphysis, metaphysis, and diaphysis?
From the "EMD" of the bone
| - different parts of bone from its end moving down bone
159
What is avascular necrosis?
- Ischemic, aseptic necrosis of bone / marrow
| - Leads to Osteoarthritis and fracture
160
Causes of avascular necrosis?
1. Trauma / fracture
2. Steroids
3. Sickle cell: dactylitis
4. Caisson disease: gas emboli
161
What is a osteoma?
- Benign bone tumor
- Normally on surface of facial bones
- Seen in Gardner syndrome
162
What is Gardner syndrome?
1. Osteoma
2. Familial adenomatous polyposis
3. Fibromatosis of retroperitoneum
163
What is osteoid osteoma?
- Benign tumor of osteoblasts with rim of reactive bone
| - Seen in
164
Tumor with rim of reactive bone in long bone of 20 yo?
Osteoid osteoma
165
What tumor has bone pain that resolves with aspirin?
Osteoid osteoma
166
What tumor is bony mass with radiolucent core?
Osteoid osteoma
167
Characteristics of osteoblastoma?
- Benign tumor of osteoblasts
- > 2cm
- Found in vertebrae
- Bone pain that does not respond to ASA
168
What is the following:
- Benign tumor of osteoblasts
- > 2cm
- Found in vertebrae
- Bone pain that does not respond to ASA
Osteoblastoma
169
What is osteochondroma?
- Benign tumor of bone with cartilage cap
- "chondro" = cartilage
- Arises as lateral projection of growth plate
170
What is the following:
- Benign tumor of bone with cartilage cap
- "chondro" = cartilage
- Arises as lateral projection of growth plate
Osteochondroma
171
What is chondrosarcoma?
- Malignant transformation of cartilage camp on osteochondroma
172
What is osteosarcoma?
- Malignant osteoblastic tumor
- Peak incidence in teenagers
- In metaphysis of long bone: distal femur, proximal tibia
173
Osteosarcoma risks?
1. Familial retinoblastoma
2. Pagets
3. Radiation
174
What is the following:
- Malignant osteoblastic tumor
- Peak incidence in teenagers
Osteosarcoma
175
What is familial retinoblastoma?
1. Bilateral retinoblastoma
| 2. Osteosarcoma
176
Presentation of osteosarcoma?
1. Pathologic fracture
2. Bone pain with swelling
3. Drags periosteum off bone: layer of connective tissue "Codman's angle"
177
Tumor in metaphysis of long bone?
Osteosarcoma
178
Which tumor pulls periosteum off bone: "Codman's angel"?
Osteosarcoma
179
"Pleomorphic cells producing osteoid?"
Osteosarcoma
180
What is giant cell tumor?
- Tumor of giant / stromal cells in young adults
- Arises in epiphysis
- Locally aggressive with recurrence
"Soap bubble sign"
181
Only tumor in epiphysis?
Giant cell tumor
182
"Soap bubble sign?"
Giant cell tumor
183
What is ewing sarcoma?
- Malignant growth of poorly differentiated cells of neuroectodermal origin
- Male kids
- Diaphysis of long bones
- Onion skin on Xray
184
What is following:
- Malignant growth of poorly differentiated cells of neuroectodermal origin
- Male kids
- Diaphysis of long bones
- Onion skin on Xray
Ewings
185
Translocation in ewings?
11:22
186
What is 11:22 translocation seen in?
Ewing's sarcoma: 33 is his jersey number
187
What is chondroma?
- Benign tumor of cartilage
| - Medulla of hands and feet
188
Location of benign and malignant cartilage tumors?
Malignant: Pelvis / central skeleton
Benign: small bones of hands and feet
189
When are punched out osteolytic lesions seen?
Metastasis to bones
190
Presentation of prostate in bones?
Osteoblastic lesions
191
Type of cartilage at joints?
Type II: think, this is where TWO bones come together
192
What is synovium?
Lining that surrounds a joint making a capsule
| - Secretes fluid of Hyaluronic acid to lubricate joint
193
What is degenerative joint disease?
- Degeneration of articular cartilage from wear and tear
- Seen with age, obesity, and trauma
* *Joint stiffness in morning that worsens throughout day
194
When is stiffness worsening through day seen?
Degenerative joint disease
195
What hand joins is degenerative joint disease in?
DIP
| PIP
196
What is eburnation?
- Rubbing / polishing of bone seen in degenerative joint disease from lack of cartilage
- Bone rubbing against bone will the to reactive osteocytes
197
When are osteocytes seen in DIP and PIP?
Degenerative joint disease
198
What are heberden and bouchard nodes?
- Osteocytes seen in DIP and PIP in degenerative joint disease
199
Genetic association of RA?
HLA-DR4
200
What is HLA DR4 implicated in?
RA
201
Hallmark of RA?
Synovitis leading for formation of pannus: inflamed granulation tissue
202
When is this seen:
| Synovitis leading for formation of pannus
RA
| Pannus = inflamed granulation tissue
203
What is occurring in the synovitis in RA?
- Myofibroblasts in granulation tissue of pannus cause:
1. Ankylosis: fusion of joint
2. Movement of joint in different directions
3. Destruction of articular cartilage
204
What is ankylosis?
Fusing of joint that can be seen in RA from myofibroblast contraction
205
When is morning stiffness improving during day seen?
RA
| - Compare it to inflammation of your throat when you wake up in morning it is worse then improves during day
206
Joints in RA?`
Symmetrical involvement of:
1. PIP
2. Wrists
3. Elbows
4. Ankles
5. Knees
* **Sparing DIP
207
When is symmetric` joint involvement sparing DIP seen?
RA
208
Joint disease with systemic signs?
RA
209
What are rheumatoid nodules?
- Central area of necrosis surrounded by epithelioid histiocytes
210
Associated features of RA?
1. Vasculitis
2. Rheumatoid nodules
3. Baker Cysts: seen in leg pit
211
Lab findings in RA?
- IgM antibody against FC portion of IgG
212
When is the following seen:
| - IgM antibody against FC portion of IgG
RA
213
Sequelae of RA?
1. Anemia of chronic disease
| 2. Secondary amyloidosis: deposition of AA
214
What is deposited in secondary amyloidosis?
- SAA made in liver converted to AA which is deposited in tissues
215
Characteristics of seronegative spondyloarthropathies?
1. Lack rheumatoid factor
2. Axial skeleton
3. HLA B27 association
216
Joint involvement in ankylosing spondyloarthritis?
1. Spine
| 2. SI joint
217
Presentation of ankylosing spondyloarthritis?
Young male with:
1. Low back pain
2. Fusion of vertebrae: bamboo spine
3. Uveitis
4. Aortitis
218
When is bamboo spine seen?
Ankylosing spondylitis
219
Characteristics of psoriatic arthritis?
- Psoriasis
- Axial and distal skeleton
- "Sausage fingers of DIP"
220
When are sausage fingers seen?
Psoriatic arthritis
221
Presentation of infectious arthritis?
N. gonorrhoeae or S aureus infx causing:
1. Warm, red joint with limited motion
2. Fever
3. Increased WBC
4. Increased ESR
* **Single joint, usually knee
222
What is happening in gout?
Monosodium urate deposition in tissues due to increased uric acid
223
How do we arrive at uric acid?
1. Purine degradation products AMP / GMP taken into enterocyte
2. GMP broken to guanine, AMP to HYPOxanthine
3. Both products broken to xanthine
4. Xanthine oxidase converted to uric acid
5. Uric acid filtered by kidney unless too much
224
What is xanthine oxidase?
- In breakdown of purines, converts xanthine to uric acid
225
Causes of secondary gout?
1. Leukemia and myeloproliferative: high cell turnover - increased purines
2. Lesch nyhan
3. Kidney failure
226
What is lesch nyhan?
HGPRT deficiency in purine salvage pathway leading to increased uric acid causing:
1. Gout
2. Mental retardation
3. Self mutilation
227
What is HGPRT?
Salvages Hypoxanthine and guanine from purine degradation pathway
- Leads to decreased uric acid
228
What is the following:
1. Gout
2. Mental retardation
3. Self mutilation
Lesch Nyhan
229
What causes inflammation in acute gout?
MSU crystals in joints are activating neuts
230
What is podagra?
- Painful arthritis of great toe seen in gout
231
Why does booze cause gout?
Byproducts of alcohol compete with uric acid for excretion
232
What are tophi?
- Uric acid crystals in tissues and joints that is hallmark of chronic gout
- Which chalky deposits on histo
233
Lab in gout?
- Needled shaped crystals with NEGATIVE birefringence under polarized light
- When flat = yellow "When lay low, yellow"
234
What does negative birefringence mean?
- When flat = yellow "When lay low, yellow"
| Seen in gout UA crystals
235
What is pseudogout?
- Ca pyrophosphate crystals in joints
| - Rhomboid crystals with weak positive birefringence
236
What is following:
| - Needled shaped crystals with NEGATIVE birefringence under polarized light
Gout
237
What is following:
| - Rhomboid crystals with weak positive birefringence
Pseudogout
| - Think pseu, positive, pyrophosphate, all begin with Ps
238
What is dermatomyositis?
- Inflammatory disease of skin and muscle often associated with gastric carcinoma
239
Presentation of dermatomyositis?
1. Proximal, bilateral muscle weakness: cant raise arms of climb stairs
2. Rash of upper lids
3. Malar rash
4. Red papules on knees, knucles, elbows
240
What is following:
1. Proximal, bilateral muscle weakness: cant raise arms of climb stairs
2. Rash of upper lids
3. Malar rash
4. Red papules on knees, knucles, elbows
Dermatomyositis
241
Labs in dermatomyositis?
1. Increased creatine kinase
2. Positive ANA
3. Anti JO-1 Ig
4. Perimysial inflammation with perifascicular atrophy
242
When is DSDNA Ig seen?
Lupus
243
When is following seen:
| Perimysial inflammation with perifascicular atrophy
Dermatomyositis
244
What is perimysium? When is it inflamed?
Connective tissue surrounding muscle fascicles: inflamed in dermatomyositis
***Think, the perimysium is on outside of fiber close to skin so it must be inflamed in dermatomyositis
245
What is endomysium? When is it inflamed?
Connective tissue between fibers
| - Inflamed in polymyositis
246
What is polymyositis?
- Inflammatory condition of skeletal endomysium
- No skin involvement
- CD8 and necrotic fibers seen
247
What is X linked muscular dystrophy? Caused?
- Degenerative muscles wasting in which muscle is replaced by adipose tissue
- Caused by DELETIONS of dystrophin
248
What is following:
| - Degenerative muscles wasting in which muscle is replaced by adipose tissue
Muscular dystrophy
249
What is dystrophin?
- Largest gene in humans:
- DELETED in DMD
- Anchors muscle cytoskeleton to ECM
250
DMD presentation?
1. Proximal muscle weakness at 1 yo
2. Calf pseudohypertrophy
3. Elevated CK
251
Death in DMD?
Cardiac or respiratory failure once they become involved
252
What is becker muscular dystrophy?
- Mutations in dystrophin
| - Similar to DMD but milder as DMD is deletion
253
Transmission at NMF?
- Ca channel opening allows for AcH release
| - AcH binds nicotinic receptors on endplate
254
What happens in myasthenia gravis?
- Ig binds nicotinic receptor at NMJ endplate
- Receptor is not destroyed, Ig just creates competition
- With rapid firing, not enough Ach Can be released to fire muscle
* *Classically seen in eyes = ptosis and double vision
255
When is muscle weakness worse with use and better with rest seen?
MG
256
Association of MG?
1. Thymoma - improved if removed
| 2. Thymic hyperplasia
257
What happens in eaton lambert?
Ig vs presynaptic Ca channel
- Seen in small cell carcinoma of lung
- Proximal muscles involved sparing eyes
- Improves with use
258
Muscles in MG and eatons?
MG: eye with ptosis is first
Eaton: eye spared, proximal muscles infected
259
MG eaton improve or worsen with use?
MG: worsen
Eaton: improve
260
When is lipoblast seen?
Liposarcoma
261
When is cardiac rhabdomyoma seen?
Tuberous sclerosis
262
Which tumor is desmin +?
Rhabdomyosarcoma
| - Often seen in vagina of young girl
263
What does basement membrane separate?
Epidermis from underlying dermis
264
Layers and functions of epidermis?
Moving up from basement:
1. Basalis: stem cell layer
2. Spinosum: connected by desmosomes
3. Granulosus: granules in cells
4. S. corneum: keratin in cells
265
What are desmosomes?
Connect the keratinocytes in S. basalis
266
What is in dermis?
1. Connective tissues
2. Blood vessels moving up to dermis
3. Hair cells
4. Sebaceous glands (sweat)
267
Are there blood vessels in epidermis?
No
268
Another name for eczema?
"Atopic dermatitis"
269
What is atopic dermatitis?
"Eczema"
- Itchy, red, oozing rashing with vesicles and edema
- Face and flexor surfaces
- Type I HSR associated with asthma and rhinitis
270
What is following:
| - Itchy, red, oozing rashing with vesicles and edema on face and flexor surfaces
Atopic or contact
271
Atopic dermatitis associations?
Type I HSR associated with:
1. Asthma
2. Allergies
272
What is contact dermatitis?
- Same appearance of atopic dermatitis but due to exposure to allergen: Itchy, red, oozing rashing with vesicles and edema
* **Not a type I HSR: could be IV
273
What type of HSR are nickel and IVY?
Type IV
274
Drug causing contact dermatitis?
Penicillin
275
Lesions seen in acne vulgaris?
1. Comedones: white and black heads
2. Nodules
3. Pustules: pimples
276
Cause and pathology of acne?
- Chronic inflammation of hair follicles and sebaceous glands
- Hormone induced increased sebum and excess keratin production in epithelial cells of follicle = blockage: comedones
- Propionibacterium acnes = inflammation
277
How does P. Acnes cause acne?
- Keratin blocks follicle and excess sebum fills it = comedone
- P. Acnes infects and releases lipases breaking down sebum releasing inflammatory FFAs = inflammation = pimple
278
Acne treatment?
1. Benzoyl peroxide: antibiotic
| 2. Isotretinoin: vitamin a derivatives block keratin production
279
What is psoriasis?
- Well circumscribed salmon plaques with silver scale
- Usually on extensors and scalp
- Pitting of nails can be seen
- Hyperplasia and epidermal thickening: acanthosis
- Parakeratosis
280
What is following:
| - Well circumscribed salmon plaques with silver scale
Psoriasis
281
Cause of psoriasis?
- Excessive keratinocyte proliferation
- Possibly autoimmune and associated with HLA c
- Can arise in areas of trauma
282
Genetics of psoriasis?
HLA C: say """CCCCCC-riassis"
283
What is hyperplasia with increased thickening of epidermis seen in?
Acanthosis: characteristic of pWsoriais
284
When are parakeratosis and acanthosis seen?
Psoriasis
285
When / what are munro microabscesses?
- Seen in psoriasis
| - Neuts deposited in excess parakeratosis
286
When is elongation of dermal papillae seen?
Psoriasis: allows vessels to protrude into epidermal areas where not normally found which is why plaques bleed when come off
287
What is auspitz sign?
- Bleeding when plaques picked off in psoriais
288
Psoriasis Rx?
1. Steroids
2. UVA light with psoralen: damages keratinocytes - "PUVA"
3. Immune madulators
289
What is lichen planus?
- Pruritic, polygonal, planar, purple patches
- Often have white lines on surface: Wickham striae
- Can be seen in mouth
290
What is inflammation of dermal epidermal junction with sawtooth appearance?
Lichen planus
291
Histo of lichen planus?
Inflammation of dermal epidermal junction with sawtooth appearance
292
Association of lichen planus?
Chronic HCV
293
How does a blister arise?
- Separation of layers of skin = bubble
| - Can happen between various layers
294
What is pemphigus vulgaris?
- Autoimmune destruction of desmosomes: connect keratinocytes in spinosum
- IgG vs. desmoglein
- Fishnet on IF of IgG around keratinocytes
- Blister is between intact basal and rest of epidermis
- Thin epidermal wall on top of blister that easily ruptures
295
What is blister on top of intact basal layer?
Pemphigus vulgaris: IgG against desmoglein of desmosomes
296
What is acantholysis?
Separation of keratinocytes
297
What does hemidesmosome do?
Attach basal cell to basement layer: attacked in bullous pemphigoid
298
Where does pemphigus vulgaris present?
Skin AND oral mucosa
299
What is bullous pemphigoid?
- Autoimmune destruction of hemidesmosomes by IgG against basement membrane
- Subepidermal blisters with oral sparing
300
Which blister is on mouth?
Pemphigus vulgaris: think it would be "vulgar" looking to have blister on mouth
301
Which Blister is thicker?
Bullous pemphigoid: think, it is thicker because the entire epidermal layer is on top and BM is on bottom and "Bullous" starts with B
302
What is dermatitis herpetiformis?
- IgA deposition at tips of dermal papillae
- Itchy grouping of bullae and vesicles
- Seen in celiacs
303
What is erythema multiforme?
- HSR withtargetoid rash and bullae
| - Often seen in HSV
304
What is SJS?
1. Erythema multiforme with oral involvement
| 2. Fever
305
What is TEN?
"Toxic epidermal necrolysis" severe SJS
1. Sloughing of skin
2. From drug rxn
306
What causes impetigo?
Staph or pyogenes
307
What causes cellulitis?
Staph or pyogenes
308
What can cellulitis progress to?
Necrotizing fasciitis
309
What is necrotizing fasciitis?
1. Necrosis of sub q tissue from infx
| 2. CO2 production = crepitus
310
Layer separated in scalded skin?
S. Granulosus
311
Where does TEN occur?
Dermal / epidermal junction
312
What is verruca?
AKA wart
313
What is molluscum contagiosum?
Firm, pink umbilicated papule from POX virus
314
What is seborrheic keratosis?
Benign proliferation of squamous cells common in elderly
| - Raised grey plaque with stuck on appearance
315
What are circular spaces with abundant pink keratin / pseudo cysts indicative of on histo?
Seborrheic keratosis
316
What is Leser trelat sign?
1. Sudden onset of multiple Seborrheic keratosis
| 2. Usually with GI carcinoma
317
When is epidermal hyperplasia with darkening of skin seen?
1. Insulin resistance
| 2. Malignancy
318
What is xeroderma pigmentosum? What does it put you at risk for?
AR defect in nucleotide excision repair enzymes
| - At risk for BCC
319
What does UVB do to skin?
- Forms pyrimidine dimers that need to be repaired by nucleotide excision repair
- Enzyme is deficient in xeroderma pigmentosum putting you at risk for BCC
320
What is following:
| - Elevated nodule, central necrosis, dilated vessels surrounding
BCC
321
Which skin cancer shows peripheral palisading?
BCC
322
BCC prognosis?
Rarely metastasizes
323
Risks for SCC?
1. Immunosuppression
2. Arsenic
3. Chronic inflammation: scar from burn / draining sinus tract
4. Actinic keratosis
324
Skin cancer often appearing on scars?
SCC
325
Which cancers present on upper and lower lip?
"Bull shit"
Upper: BCC
Lower: SCC
326
What is actinic keratosis?
- SCC precursor
| - HYPERkeratotic scaly plaque
327
What is a hyperkeratotic scaly plaque?
Actinic keratosis - risk for SCC
328
What is keratoacanthoma?
- Well differentiated SCC that rapidly progresses, then rapidly regresses
- Cup shaped tumor with keratin debris in center
329
What is following:
- Well differentiated SCC that rapidly progresses, then rapidly regresses
- Cup shaped tumor with keratin debris in center
Keratoacanthoma
330
How do melanocytes work? Where are they found?
- Found in basal layer of epidermis
- Take tyrosine to make melanin in melanosomes
- Melanin is passed to keratinocytes causing pigmentation
331
Origin of melanocytes?
Neural crest in nature - S100 +
332
What is vitiligo?
Localized autoimmune destruction of melanocytes = loss of pigmentation
333
What is local autoimmune destruction of melanocytes?
Vitiligo
334
What is albinism?
- Congenital lack of pigmentation from defect in tyrosinase enzymes impairing melanin production
- Can only involved eyes or eyes and skin
335
Why do freckles darken relative to neighboring cells?
Increased numbers of melanosomes
336
What is melasma?
Mask like hyperpigmentation of cheeks associated with OCPs and pregnancy
337
What a nevus?
"mole"
| - Benign neoplasm of melanocytes
338
Is hair growing from mole a good sign?
Yes, this is not seen in melanoma as they would destroy the follicles
339
Are nevis precursors to melanoma?
They can be if they develop dysplasia
340
ABCs of melanoma?
Asymmetry
Border irregularity
Color changes throughout
Diameter > 6 mm
341
Key feature for risk of metastasis in melanoma?
Depth of invasion
342
4 Types of melanoma?
1. Lentigo maligna
2. Superficial spreading
3.
4.
343
What is lentigo maligna melanoma?
```
Lentiginous proliferation (along dermal line) of melanocytes
- Good prognosis as not much depth of invasion
```
344
What is the following:
| Melanocyte proliferation along dermal line
Lentigo melanoma
345
What is superficial spreading melanoma?
Dominant early radially phase:
| - Good prognosis as not going deep
346
Which melanoma has dominant early radial phase?
Superficial spreading
347
What is nodular melanoma
- Early vertical phase: poor prognosis
| - Pushes skin up as it goes deep which is why it is called nodular
348
Which melanoma has early vertical phase?
Nodular
349
What is acral lentiginous melanoma?
- Palms and soles of dark skinned folks
| - Not relation to UV light
350
What is melanoma of palms and soles?
Acral lentiginous
351
Risk for having a child with achondroplasia?
Advanced paternal age
352
What is decrease in trabecular mass despite normal mineralization and lab values?
Osteoporosis
353
Diagnostics of osteoporosis?
Osteoporotic: > 2.5 SDs from mean
Osteopenic: 1 SD from mean
354
When are chalk stick fractures in long bones seen?
Pagets
355
How will paget's of bone kill you?
1. AV shunts through bone: high output HF
| 2. Osteogenic sarcoma
356
Increasing hat size and elevated alk phos?
Pagets
357
2 bone diseases with normal labs?
1. Osteoporosis
| 2. Osteopetrosis
358
Labs in rickets?
1. Low Ca
2. Low P
3. Increased Alk phos
4. Increased PTH
359
Bone tumor with homer wright rosettes?
Ewing sarcoma
360
Characteristics of type III HSR?
Ig / complex mediation
361
When is DIP spared?
RA
362
What does probenecid do?
Cause increased uric acid excretion
363
Where does pseudogout present?
Usually larger joints
364
Presentation of sjogren's?
1. Xerophthalmia: Dry eyes / "sand in eyes"
2. Xerostomia: dry mouth / dysphagia as makes it hard to swallow
3. Enlarged parotids
4. RA
* **caused by exocrine destruction of salivary and lacrimal glands
365
What is the following?
1. Xerophthalmia
2. Xerostomia
3. Enlarged parotids
4. RA
Sjogren
366
Antibodies in sjogren's?
1. Anit RNP
2. Anti Ro / SSA
3. Anti La / SSB
367
When is following seen:
1. Anit RNP
2. Anti Ro / SSA
3. Anti La / SSB
Sjogrens
368
Diagnosis in teenager with red hot joint?
Gonorrhea
369
Bone disease with HLA B27?
Seronegative spondalropathies
370
Pencil / cup deformity?
Psoriatic arthritis
371
Joint disease caused by IBD?
Sacroiliitis
372
What does lupus cause in heart?
1. Libman sachs endocarditis
| 2. Pericarditis
373
What is chest pain relieved by leaning forward and worse on lying down and deep breaths?
Pericarditis
374
SLE on kidney?
1. Diffuse proliferative glomerulonephritis
2. Membranous glomerulonephritis
* *Type III HSRs
375
4 serum markers for lupus?
1. Anti DSDNA
2. Antismith
3. ANA
4. Antihistone: drug induced lupus
376
Drugs causing drug induced lupus?
1. Hydralazine
2. Procainamide
3. Isoniazid
377
Characteristics of antiphospholipid syndrome?
1. 1st semester clot or abortion
2. False positive VDRL
3. Falsely prolonged PTT
4. Lupus anticoag / anticardiolipin / Anti B2
378
What is following:
1. + ANA
2. + anti-U1-RNP
Mixed connective tissue disease
379
Schaumann and asteroid bodies?
Sarcoid
380
Sarcoid presentation?
1. Restrictive lung disease
2. Bell palsy
3. Erythema nodosum
4. Uveoparotitis
381
Labs in sarcoid?
1. Increased ACE
2. Increased Ca: macs in granulomas activate vitamin D
3. Increased CD4:8 ratio
382
What is polymyalgia rheumatic?
1. Pain and stiffness in hips and shoulders
383
Women > 50 with muscle pain and no weakness?
Polymyalgia rheumatica
384
Association of Polymyalgia rheumatica?
Giant cell arteritis
385
What is polymyositis?
- Progressive, symmetric, proximal muscle weakness
386
What is myositis ossificans?
Ca deposits in muscles
387
What is scleroderma?
- Widespread collagen deposition in body = fibrosis
| - Tight, puffy skin
388
When is SCL 70 seen?
Diffuses scleroderma
389
Lab in Diffuses scleroderma?
SCL 70
390
What is CREST? Lab
```
*Anticentromere Ig
Calcinosis
Raynaud's
Esophageal dysmotility
Sclerodactyly
Telangiectasia
```
391
When is anticentromere Ig seen?
CREST
392
Cause of Raynaud's?
Excess Alpha receptors on vessels of hands = constriction
