MUSCULOSKELETAL, SKIN, AND CONNECTIVE TISSUE- Anatomy and physiology Flashcards
1
Q
Epidermis Layers
A
Stratum Corneum Stratum Lucidum Stratum Granulosum Stratum Spinosum Stratum Basale
2
Q
In which epidermis layer i sthe Keratin?
A
Stratum corneum
3
Q
Which kind of intercellular conections exist in Stratum spinosim?
A
Desmosomes
4
Q
Which cells are found in Stratum basale?
A
Stem cell site
5
Q
Epithelial cell junctions
A
Tight junction Adherens junction Desmosome Gap Junction Hemidesmosome
6
Q
Alternative name for Tight junction
A
Zonula occludens
7
Q
What is the function of tight junction?
A
Prevents paracellular movement of solutes
8
Q
What composes Zonula occludens?
A
Claudins and occludins
9
Q
Alternative name for Adherens junction
A
Zonula adherens
10
Q
Where are located Adherens junctions?
A
Below tight junction
11
Q
Which is the function of Zonula adherens?
A
Forms “belt connecting actin cytoskeletons of adjacent cells with CADherins
12
Q
What are the CADherins?
A
Ca2+ dependent adheison proteins
13
Q
Loss of E cadherin promotes…
A
Metastasis
14
Q
Alternative name for Desmosomes
A
Macula adherens
15
Q
Which is the structural importance of Desmosomes
A
Structural Support via keratin interactions
16
Q
Which disease is caused by Autoantibodies against desmosomes?
A
Pemphigus Vilgaris
17
Q
Channel proteins called connexons
A
Gap junction
18
Q
What is the function of Gap junction?
A
Permit electrical and chemical communication between cells
19
Q
What is the function of Hemidesmosome?
A
Connects keratin in basal cells to underlying basement membrane
20
Q
Disease characterized by Autoantibodies against Hemidesmosome
A
Bullous pemphigoid
21
Q
What is the function of Integrins?
A
Membrane proteins that maintain integrity of basolateral membrane
22
Q
How do integrins maintain integrity of basolateral membrane?
A
By binding to collagen and laminin in basement membrane
23
Q
How is knee injury presented?
A
With acute knee pain and signs of joint injuriry/ instability
24
Q
What does Anterior drawer sign means?
A
ACL (Anterior Cruciate Ligament) injury
25
What does Posterior drawer sign means?
PCL (Posterior Cruciate Ligament) injury
26
Signs of Joint injury/ instability of Knee
```
Anterior drawer sign
Posterior drawer sing
Abnormal passive abduction
Abnormal passive adduction
McMurray test
```
27
Which kind of stress is Abnormal passive abduction?
Valgus Stress
28
Which kind of stress in Abnormal passive adduction
Varus Stress
29
How is Abnormal passive abduction translated?
As MCL (Medial collateral ligament) injury
30
What does Abnormal passive adduction?
LCL (Lateral collateral ligament) injury
31
How is McMurray test evaluated?
Pain on external rotation → Medial meniscus
| Pain on internal rotation → Lateral meniscus
32
When is Unhappy triad presented?
Common injury in contact sports due to lateral force applied to a planted leg
33
In what does Unhappy triad consists?
Of damage to the ACL, MCL, and medial meniscus (attached to MCL
34
Which is the most common Meniscus injury?
Lateral meniscus injury is more common
35
Which nerve block relieve pain of delivery?
Pudendal nerve block
36
Where is pudendal nerve?
Ischial spine
37
Where is McBurney point?
2/3 of the distance between the umbilicus and the anterior superior iliac spine
38
Clinically how you identify the point of Lumbar puncture?
With iliac crest
39
Rotator cuff muscles
Supraspinatus
Infraspinatus
Teres minor
Subscapular
40
Who innervates Supraspinatus?
Suprascapular nerve
41
What is the function of Supraspinatus?
Abduct arm initially
42
After Supraspinatus abduct the arma, who manage the complete abduction of arm?
Deltoid
43
Most common rotator cuff injury
Supraspinatus
44
Who innervates Infraspinatus?
Suprascapular nerve
45
Which muscles are innervated by suprascapular nerce?
Supaspinatus
| Infraspinatus
46
Laterally rotates arm
Infraspinatus
47
Muscle affected by pitching injury
Infraspinatus
48
Which nerve innervates Teres minor?
Axilalary nerve
49
What is the function of Teres minor?
Adduct and laterally rotate
50
Structure inervated by Subscapular nerve
Subscapularis
51
Medially rotates and adducts arm
Subscapularis
52
Which nerve branches innervate primarily the rotator cuff muscles
By C5-C6
53
Wrist bones
Scaphoid, Lunate, Triquetrum, Pisiform
| Hamate, Capitate, Trapezoid, Trapezium
54
Bone palpated in anatomical snuff box
Scaphoid
55
Most commonly fractured carpal bone
Scaphoid
56
What other risk do Scaphoid bone has?
Is prone to avascular necrosis owing to retrograde blood supply
57
What could be the result of Dislocation of lunate?
May cause acute carpal tunnel syndrome
58
What could be the result of a fall on an outstretched hand that damages the hook of the hamate?
Can cause ulnar nerve injury
59
What happens in Carpal tunnel syndrome?
Entrapment of median nercie in carpal tunnel
60
Pathophysiology of carpal tunnel syndrome. And which are the symptoms?
Nerve compression → paresthesia, paim, and numbness in diestribution or median nerve
61
What is affected in Guyon canal syndrome?
Compression of the ulnar nerve at the wrist or hand
62
In whom is often seen Guyon canal syndrome?
In cyclists due to pressure from handlebars
63
How else is Erb palsy known?
Waiter's tip
64
What is injure in Erb palsy?
Traction or tear of upper trunk
65
Which roots form Upper trunk, affected in Erb palsy?
C5-C6 roots
66
Cause of Erb palsy in infants
Lateral traction on neck during delivery
67
Cause of Waiter's tip palsy in adults
Trauma
68
Which are the three possbile muscle affected by Erb palsy?
Deltoid, supraspinatus
Infraspinatus
Biceps brachii
69
Functional deficience in case Deltoid or supraspinatus are affected
Abduction (arm hangs by side)
70
When Infraspinatus is affected what do we see?
Lateral rotation (arm medially rotated)
71
What is seen in Biceps brachii lesion?
Flexion, supination (arm extended and pronated)
72
What is affected in Klumpke palsy?
Traction or tear of lower trunk
73
Which root of nerves form the lower trunk affected in Klumpke palsy
C8 and T1
74
Causes of Klumpke palsy in infants
Upward force on arm during delivery
75
Cause of Klumpke palsy in adults
Trauma
76
Muscle deficit in Klumpke palsy
Intrinsic hand muscles:
| Lumbricals, interossei, thenar, hypothenar
77
In which palsy is seen Total claw hand?
Klumpke palsy
78
What is the total claw hand?
Lumbrincans normally flex MCP joins and extend DIP and PIP joints
79
What explains Thoracic outlet syndrome?
Compression of lower trunk and subclavian vessels
80
Cervical rib injury and Pancoast tumor could cause this syndrome
Thoracic outlet syndrome
81
Muscle affected in Thoracic outlet syndrome
Same as Klumpke palsy
82
What is the functional deficit seen in Thoracic outlet syndrome
Athrophy of intrinsic hand muscles; ischemia, pain, and edema due to vascular compression
83
Lesion of long thoraci nerve
Winged scapula
84
Risk of axillary node dissection after mastectomy, and stab wounds
Winged scapula
85
Muscle affected in Wiged scapula
Serratus anterior
86
What is functional deficit seen with winged sacpula?
Inability to anchor scapula to thoracic cage → cannot abduct arm above horizontal position
87
Which nerves could be injure in case of fractured surgical neck of humerus; anterior dislocation of humerus?
Axillary
88
Who forms the axillary nerves?
C5-C6
89
What is the clinical pressentation when axillary nerve is injured?
Flattened deltoid
Loss of arm abduction at shoulder (>15 degrees)
Loss of sensation over deltoid muscle and lateral arm
90
Which nerve is formed by C5-C7?
Musculocutaneous
91
Nerve damaged by upper trunk compression
Musculocutaenous
92
The clinical pressentation of this nerve injure is with loss of forearm flexion and supination, loss of sensation over lateral forearm
Musculocutaneous (C5-C7)
93
Nerve affected by "Saturday nerve palsy"
Radial
94
Who forms the radial nerve?
C5-T1
95
What causes nerve injury of Radial nerve?
Midshaft fracture of humerus; compression of axilla (eg. due to crutches of sleeping with arm over chair)
96
Clinical pressentation of this nerve injured is with Wrist drop: Loss of elbow, wrist and finger extension
Radial Nerve injury
97
Which sensations are lost in case of Radial nerve injury?
Loss of sensation over posterior arm/forearm and dorsal hand
98
What else is seen in Radial nerve injury?
↓ grip strenght (wrist extension necessary for maximal action of flexors)
99
Which branches form Median nerve?
C5-T1
100
Nerve affected in carpal tunnel syndrome
Median nerve
101
What nerve do you suspect to be injure in case of Wrist laceration (distal)?
Median nerve
102
Other situation that could injure median nerve
Supracondylar fracture of humerus (proximal lesion)
103
The clinical pressentation of this nerve injure is "Ape hand" and "Pope's blessing"
Median nerve injury
104
Functional loss when median nerve is injured
Loss of wrist and lateral finger flexion, thumb opposition, lumbricals of 2nd and 3rd digits
105
Nerve injured when loss of sensation over thenar eminence and dorsal and palmar aspects of lateral 3 1/2 fingers with proximal lesion
Median nerve injury
106
Which sign is seen in median nerve lession in carpal tunnel syndrome?
Tinel sign
107
What is the Tinel signs? When is seen?
Tingling on percussion, in carpal tunnel syndrome
108
Nerves that form the Ulnar nerve
C8-T1
109
Nerve affected in fracture of medial epicondyle of humerus "funny bone" (proximal lesion)
Ulnar (C8-T1)
110
Distal lession of Ulnar
Fractured of hook of hammate
111
What is seen on digit extension when ulnar nerve is damaged?
"Ulnar claw"
112
Clinical presentation of Proximal lession ofr Ulnar nerve
Radial deviation of wrist upon flexion
113
Loss of flexion of wrist and medial fingers, abduction and adduction of fingers (interossei), actions of medial 2 lumbrical muscles
Ulnar nerve injury (C8-T1)
114
What sensation is loss in Ulnar nerve injury?
Loss of sensation over medial 1 1/2 fingers including hypothenar eminence
115
Who forms Recurrent branch of median nerve?
C5-T1
116
How is Recurrent branch of median nerve injured?
By superficial laceration of palm
117
Clinical presentation of Recurrent branch of median nerve injury
"Ape hand"
118
Which muscles function is lost if Recurrent branch of median nerve is injured?
Loss of thenar muscle group
119
Which mucles form the thenar muscle group?
Opposition, Abduction and Flexion thumb
120
Which sensations are lost in Recurrent branch of median nerve injury?
None
121
Which muscles manage the balance on the hand guring rest?
A balance between the extrinsic flexors and extensors of the hand, as well ad the instrinsic muscles of the hand
122
Which are the particular muscles related to the balance of the hand?
Lumbrical muscles
123
What is the function of Lumbrical muscles?
Flexion of metacarpophalangeal (MCP), extension of Distal and proximal Interphalangeal joints (DIP and PIP)
124
When is "clawing" of the hand seen?
Seen best with distal lesions of median or ulnar nerves
125
What else is seen in "clawing" hand?
Remaining extrinsic flexors of the digits exaggerate the loss of the lumbricals
126
Presentation of "clawing hand"
Extension of metacarpophalangeal (MCP), flexion of Distal and proximal Interphalangeal joints (DIP and PIP)
127
Which distortions of the hand is less pronunced between distal and proximal lesions?
Proximal
128
How is proximal lesion of the hand seen?
Deficits present during voluntary flexion of the digits
129
Which is the sign seen in Distal ulnar nerve lesion?
"Ulnar claw"
130
What is found in "Ulnar claw?
Extending fingers /at rest
131
In "Pope's blessing" which nerve is damege?
Proximal median nerve
132
Sign found in median nerve injury
"Median claw"
133
If proximal ulnar nerve is damage, which sign may you find?
"OK gesture" (with digis 1-3 flexed)
134
What is found in Atrophy of the thenar eminence?
Unoposable thumb → "ape hand"
135
When is Atrophy of the thenar eminence seen?
In median nerve lesions
136
Atrophy of the hypothenar eminence is seen during...
Ulnar nerve lesions
137
Nerve related to Thenar eminence
Median
138
Which is the function of both hypothenar and thenar eminences?
OAF
Oppose
Abduct
Flex
139
Opponens pollicis, Abductor pollicis brevis, Flexor pollicis brevis
Thenar eminence
140
Opponens digiti minimi, Abductor digiti minimi, Flexor digiti minimi
Hypothenar eminence
141
Abduct the fingers
Dorsal interosseous muscles
142
Adduct the fingers
Palmar interosseous muscles
143
Muscle that manage Flexion of metacarpophalangeal (MCP), extension of Distal and proximal Interphalangeal joints (DIP and PIP)
Lumbrical muscles
144
Who composes Obturator nerve?
L2-L4
145
Cause of injury of Obturator nerve
Pelvic surgery
146
The clinical presentation of this nerve injury is ↓ thigh sensation (medial) and ↓ adduction
Obturator nerve injury
147
Which branches form Femoral Nerve?
L2-L4
148
When can femoral nerve get injured?
Pelvic fracture
149
Clinical presentation of Femoral nerve injury
↓ thigh flexion and leg extension
150
L4 - S2 composed this nerve
Common peroneal nerve
151
Risk of trauma or compression of lateral aspect of leg, fibular neck fracture
Common peroneal nerve injury
152
"Steppage gait" is seen in...
Common peroneal nerve injury
153
Clinical presentation of Common peroneal nerve injury
Foot drop- inverted and plantarflexed at rest, lost of eversion and dorsiflexion
154
Which sensation is lost when common peroneal nerve is injured?
Loss of sensation on dorsum of foot
155
Which branches form the Tibial nerve?
L4-S3
156
Proximal Causes of injury of tibial nerve
Knee trauma, Baker cyst (proximal lesion)
157
Distal causes of injury of tibial nerve
Tarsal tunnel syndrome
158
Presented as inability to curl toes and loss of sensation on sole of foot
Tibial nerve injury
159
What is seen in proximal tibial nerve lesion?
Foot everted at rest with loss of inversion and platarflexion
160
Branches that become Superior gluteal nerve
L4-S1
161
A posterior hip dislocation have this risk
Superior and inferior gluteal nerve lesion
162
Polio causes damage mainly to this nerve
Superior gluteal nerve damage
163
Trendelenburg sign/gait is seen in this situation
Superior gluteal nerve damage
164
Characteristics of Trendelenburg sign/gait
Pelvis tilts because weight bearing leg cannot maintain alignment of pelvis through hip abduction (superior nerve → medius and minimus)
165
Where is the lesion in case of Superior gluteal nerve damage?
Lesion is contralateral to the side of the hip that drops, ipsilateral to extremitiy on which patient stands
166
Branches that become Inferior gluteal nerve
L5- S2
167
What you must suspect when a patient has difficulty climbing stairs, rising from seated position?
Inferior gluteal nerve injury
168
What is seen in Inferior gluteal nerve injury?
Loss of hip extension (inferior nerve → maximus)
169
Who forms Sciatic nerve?
L4-S3
170
Sciatic nerve mainly innervates...
Posterior thigh
171
Sciatic nerve splits into...
Splits into common peroneal n tibial nerves
172
Nerve of the surgical neck of humerus
Axillary
173
Artery of surgical neck of humerus
Posterior circumflex
174
Nerve of Axila/lateral thorax
Long thoracic
175
Artery of Axila/lateral thorax
Lateral thoracic
176
Nerve of Midshaft of humerus
Radial
177
Artery of Midshaft of humerus
Deep Brachial
178
Nerve of Distal humerus/ cubital fossa
Median
179
Artery of Distal humerus/ cubital fossa
Brachial
180
Nerve of popliteal fossa
Tibial
181
Artery of popliteal fossa
Popliteal
182
Nerve of posterior to medial malleolus
Tibial
183
Artery of posterior to medial malleolus
Posterior tibial
184
From where to where does a Sarcomere includes?
From Z line to Z line
185
Which is the mid line of Sarcomere?
M line
186
Where are the mitochondrion found in muscle cells?
In Sarcoplasm
187
Where is sarcoplamic reticulum in muscle cells?
Peripheral to myofibril
188
Who conforms I band?
Actin
| Thin filaments
189
What forms A band?
Myosin and Actin
| Thick and Thin filaments superimpossed
190
What is H band?
Myosin
| Just thick filaments
191
In the first step of muscle contraction, what is the effect of Action potential depolarization?
Opens presynaptic voltage gated Ca2+ channles
192
What does the open of presynaptic voltage gated Ca2+ channles induces?
Neurotransmitter release
193
During the second step of muscle contractio, after neurotransmitter relase, what is next?
Postsynapting ligand binding leads to muscle cell depolarization in the motor end plate
194
In the third step of muscle contraction, what is happens during depolarization?
Depolarization travels along muscle cell and down T tubule
195
During the fourth step of muscle contraction, what happens next to T tubule depolarization ?
Depolarization of the voltage sensitive dihydropyridine receptor
196
What is mechanically coupled to dihydropyridine receptor?
Ryanidine receptor on the sarcoplasmic reticulum
197
Wht does the Depolarization of the voltage sensitive dihydropyridine receptor mechanically coupled to Ryanidine receptor, lead to?
Induces conformational change, causing Ca2+ release from sarcoplasmic reticulum
198
During the fifth step of muscle contraction, what happens to the release Ca2+?
Binds to troponinC, causing conformational change that moves tropomyosin out of the myosin binding groove on actin filaments
199
During the last step of muscle contraction, what happens to the myosin?
Mysoin releases bound ADP and subsequently, inorganic PO4 3-
200
What is the effect of Mysoin releases bound ADP and subsequently, inorganic PO4 3-?
Displacement of myosin on the actin filament (power stroke)
201
What is the result of muscle contraction?
Shortening of H and I bandsand between Z lines (HIZ shrinkage)
202
What happens A band in muscle contraction?
Remains the same lenght (A band is always the same lenght)
203
Types of muscle fibers
Type 1 muscle
| Type 2 muscle
204
Also known as red fibers
Type 1 muscle
205
Which are the slow twitch muscle fibers?
Type 1
206
Why are type 1 muscle red?
Resulting from ↑ mitochondria and myoglobin concentration (↑ oxidative phosphorylation)
207
What is the result of ↑ mitochondria and myoglobin concentration (↑ oxidative phosphorylation) in type 1 muscle?
Sustained contraction
208
Which are the fast twitch muscle fibers?
Type 2
209
Also known as white fibers
Type 2 muscle
210
Explain the white color of Type 2 muscle fibers
Resulting from ↓ mitochondria and myoglobin concentration (↑ anaerobic glycolysis)
211
Which muscle fibers have hyperthrophy as a result of weight training?
Fast twitch muscle fibers
| Type 2 muscle
212
Main element to detonate smooth Muscle contraction
↑ Ca2+
213
Main element that manage smooth muscel relaxation
Nitric oxide
214
Ca2+ channels in smooth muscle
L type voltage gated Ca2+ channel
215
Once the membrane of smooth muscl is depolarized, what is next?
↑ Ca2+
216
After Ca2+ is increased in smooth muscle cells, what happens next?
↑ CA2+ -calmodulin complex
217
What is the effect of ↑ CA2+ -calmodulin complex in smooth muscle cell?
Positively stimulates Myosin light chain kinase (MLCK)
218
Final result of Positively stimulated Myosin light chain kinase in smooth muscle cell
Stimulates Myosin P+ actin which leads to contraction (via cross bridging)
219
In order to relax the smooth muscle, what is the effect of Nitric oxid?
Positively stimulates Guanylate cyclase
220
What is the effect of Guanylate cyclase in smooth muscle cell?
Converts GTP to cGMP
221
Once cGMP is made in smooth muscle relaxation, what happens next?
cGMP positively stimulates Myosin light chain phosphatase (MLCP)
222
What is the final result of stimulated Myosin light chain phosphatase (MLCP)?
From Myosin P+ actin, change to Myosin+ actin, which leads to smooth muscle relaxation
223
Types of Bone formation
Endochondral ossification
| Membranous ossification
224
Which bones present endochondral ossification?
Bones of axial and appendicular skeleton, and base of the skull
225
Which is the model of endochondral ossification?
Cartilaginous model of bone is first made by chondrocytes
226
What happens after the cartilaginous model of bone in endochondral ossification?
Osteoclasts and osteoblasts later replace with woven bone and the remodel to lamellar bone
227
In adults when does woven bone occur?
After fractures and in Paget disease
228
Which bones present Membranous ossification?
Bones of calvarium and facial bones
229
How is woven bone formed in Memebranous ossification?
Directly without cartilage. Later remodeled to lamellar bone
230
How do osteoblasts build bone?
By secreting collagen and catalyzing mineralization
231
From which cells do osteoblasts differentiate? and where?
From Mesenchymal stem cells in periostum
232
What are the osteoclasts? What is their function?
Multinucleated cells that dissolve bone by secretting acid and collagenanses
233
From which cells do osteoclasts differentiate? and where?
Monocytes/ macrophages
234
What is the effect of PTH in bone cells?
At low, intermitettent levels , exerts anabolic effects (building bone) on osteoblasts and osteoclasts (indirect)
235
Cause of chronic high PTH levels
Primary hyperparathyroidism
236
What is the effect of Chronic high PTH levels?
Catabolic effects (osteitis fibrosa cystica)
237
What is the effect of Estrogen at bone?
Inhibits apoptosis in bone forming osteoblasts and induces apoptosis in bone resorbing osteoclasts
238
What is the effect of estrogen deficiency in bone?
Excess remodeling cycles and bone resoption lead to osteoporosis
