for MT1 Lec Flashcards
1
Q
CNS
A
brain
b. spinal cord
c. contained within the skull and vertebral column
d. connected to the body through the peripheral nervous system (PNS)
2
Q
PNS
A
outside the CNS, but connected to it by nerves
3
Q
nerves
A
bundles of hundreds or thousands of axons (nerve fibers) that are widely distributed throughout the body—trunk, limbs, head, neck, and internal organs.
i) cranial nerves
ii) spinal nerves
iii) autonomic nerves
4
Q
ganglia
A
collections of neurons OUTSIDE the CNS
5
Q
spinal ganglia/dorsal root ganglia
A
clusters of nerve cells located just outside the spinal cord that help transmit SENSORY information, like pain or temperature, from the body to the brain.
6
Q
somatic (VOLUNTARY) nervous system
A
somatic motor and somatic sensory
7
Q
somatic motor
A
provides motor information from the CNS to skeletal
muscles for voluntary control of movement and posture
8
Q
somatic sensory
A
provides conscious sensation to the CNS from skin, mucosal surfaces and organs
9
Q
autonomic (visceral, involuntary) Nervous System (ANS)
A
Reflex control of smooth muscle in many organ systems, cardiac muscle,
and secretory glands found primarily in internal organs (viscera)
b. Sensory innervation of viscera
10
Q
Brain
A
- Contained within the skull
- Cerebrum (2 hemispheres)
- Cerebellum
- Brain stem
a. midbrain
b. pons
c. medulla oblongata
11
Q
in brain stem
A
a. midbrain
b. pons
c. medulla oblongata
12
Q
spinal cord begins as…
A
continuation of the brainstem at the foramen magnum and extends to the
level of the disc between vertebrae L 1 and L2
13
Q
where in the vertebral canal is the spinal cord located
A
upper 2/3 of vertebral canal (due to differential growth of the spinal cord and the vertebral column during late prenatal life)
14
Q
spinal segment
A
length of the spinal cord to which one pair of spinal nerves is attached
15
Q
cranial nerve pairs
A
12 pairs
16
Q
spinal nerves
A
31 pairs
i. 8 cervical
ii. 12 thoracic
iii. 5 lumbar
iv. 5 sacral
v. 1 coccygeal
17
Q
intervertebral foramina
A
openings between adjacent vertebrae in the spine that allow spinal nerves and blood vessels to pass through
18
Q
where are spinal nerves vulnerable to injury by herniated intervertebral disk or narrowing of intervertebral foramen
A
intervertebral foramina
19
Q
motor rootlets
A
emerge continuously along the ventrolateral aspect (towards the front and to the sides) of the entire spinal cord
Converge to form 31 pairs of ventral ( anterior) roots
20
Q
ventral roots innervate
A
skeletal muscle in neck, trunk and limbs
21
Q
sensory rootlets
A
enter the dorsolateral aspect (towards the BACK and to the sides) of the spinal cord
Converge to form 31 pairs of dorsal (posterior) roots
22
Q
dorsal roots terminate as
A
SENSORY endings in the SKIN
Send info toward the cell body located in the dorsal root ganglion, then through the dorsal root to SPINAL CORD
23
Q
spinal nerve length
A
short; no more than 1 cm in length
24
Q
spinal nerve
A
emerges from the spinal cord and carries both sensory information from the body to the brain and motor commands from the brain to muscles, enabling movement and sensation
- 1 ventral root combines w 1 dorsal root
25
2 primary rami
dorsal (posterior) ramus
ventral (anterior) ramus
26
dorsal (posterior) ramus
Innervates the erector spinae muscles of the back and the skin lying approximately over those muscles
27
Reflex pathways
neural circuits that enable automatic, involuntary responses to stimuli
typically very fast because they bypass higher brain centers and involve only the spinal cord or brainstem
Sensory Neuron: The receptor sends the signal through a sensory neuron to the central nervous system (CNS).
Motor Neuron: The processed signal is transmitted through a motor neuron to an effector organ (e.g., muscle or gland)
28
Dermatomes
Given spinal cord segment and its corresponding spinal nerve will consistently innervate a particular region of SKIN
Dermatomal map of the body describes the location of each dermatome
Used to localize sensory loss to specific spinal cord segments
Numb in a certain area- corresponds to a certain area in both skin and spinal cord
29
Spinal meninges
supportive layers of fibrous and elastic connective tissue that surround the spinal cord and are continuous with the cranial meninges that encircle the brain
Serve to anchor and protect the cord
30
Dura mater
Outermost covering separated from bone by epidural space (site of epidural anesthesia and epidural hematoma)
Also surrounds the brain
Extends to the S2 level of the vertebral column, where it ends as a blind sac except for a thin tubular extension- the coccygeal ligament or (dural) filum terminale- attached to the coccyx
31
Arachnoid mater
Inner to dura, separated from it by a potential subdural space
2. Extends below to S2 level, lines the dura and ends as a blind sac
32
Pía mater
Closely invests the spinal cord
At L2, continues as a thin extension, the (pial) filum terminale, which perforates the arachnoid mater and dura mater at S2 and continues within the coccygeal ligament (keeps spinal cord in place)
Separated from the arachnoid mater by the subarachnoid space, which is filled with cerebrospinal fluid (CSF)
Delicate mother
Ends with the spinal cord
33
Epidural space
between the bone and dura mater (contains venous plexuses)
34
Subdural space
potential space between the dura mater and arachnoid mater
35
Subarachnoid space
between the arachnoid mater and pia mater (contains CSF)
36
Where does the spinal cord end
level of the disc between the L1 and L2 vertebrae
37
Conus medullaris
Tapering end of the spinal cord
38
Early in fetal life, the spinal cord and vertebral column…
are co-extensive
Spinal nerves arise opposite their corresponding intervertebral foramina
39
Vertebral column grows more than
spinal cord
Roots of the lower spinal nerves must travel downward within the vertebral canal to reach their appropriate intervertebral foramina (descending roots = cauda equina)
Arachnoid membrane and the subarachnoid space continue down to the S2 vertebrae
Nerve roots of the CAUDA EQUINA based in CSF
40
Cauda equina
Descending roots after spinal cord ends between L1 and L2
41
Lumbar puncture
BELOW L2 and above S2 one can introduce a needle into the subarachnoid space without fear of penetrating the spinal cord and draw off CSF for laboratory analysis
42
Acute anterior poliomyelitis (polio)
Acute anterior poliomyelitis (polio)
Highly infectious virus
Invades nervous system and can cause total paralysis in matter of hours
Any age
Mostly children under age of three
Virus enters the body through the mouth, multiplies in the intestine, and migrates to the CNS, where it destroys ANTERIOR horn (VENTRAL ROOT) motor neurons
Result is paralysis and severe atrophy of the denervated muscles
Paralyzes muscles of lower limb ex. Of PURELY MOTOR LESION
NORMAL SENSATION
43
Herpes Zoster
The virus primarily affects sensory neurons in the DRG, but the infection can sometimes spread along the sensory nerve fibers to cause pain, a rash, and other sensory symptoms (like itching or burning).
Motor involvement in herpes zoster is rarer, but the virus can sometimes spread to the anterior horn cells or motor rootlets in the spinal cord, resulting in motor deficits.
PURELY SENSORY LESION
44
Herniated Disc
Intervertebral disc can bulge (herniate) posterolaterally and compress the spinal nerve in or near the intervertebral foramen, resulting in pain and/or weakness in the distribution of the affected spinal nerve
Mixed motor AND sensory lesion, as are most peripheral nerve disorders
45
General features of Autonomic nervous system
Largely INVOLUNTARY
The autonomic nervous system (ANS) controls involuntary functions.
It regulates smooth muscle, heart, and glands.
It uses two neurons: preganglionic (CNS) and postganglionic (ganglia).
The sympathetic and parasympathetic systems work together.
46
Where are the preganglionic neurons located EXCLUSIVELY
located exclusively in the T1-L2 spinal
cord segments, in the lateral horn of the gray matter.
47
What happens when the axons of preganglionic neurons leave the spinal cord through the VENTRAL roots
enter the sympathetic trunk, where they travel to the appropriate level and synapse
with postganglionic neurons located with the sympathetic trunk (chain) ganglia.
48
Sympathetic trunk
Runs alongside spinal column
Location: Runs from the base of the skull to the coccyx, alongside the vertebral column.
Structure: Composed of a series of sympathetic ganglia (clusters of nerve cell bodies) connected by nerve fibers.
Function: It allows sympathetic nerve fibers to travel to various organs, controlling functions like heart rate, blood pressure, and digestion.
Communication: Provides pathways for preganglionic fibers to synapse with postganglionic neurons that reach target organs.
49
Axons of the postganglionic neurons leave the sympathetic trunk to
Join any of the 31 corresponding spinal nerve pairs
50
Where does sympathetic innervation of smooth muscle and glands in the head come from
postganglionic neurons in the superior cervical sympathetic ganglion, whose axons
follow the internal and external carotid arteries to reach the head.
51
Where do parasympathetic preganglionic neurons travel in
cranial nerves III, VII, IX, & X, and in spinal nerves S2-S4
52
How do parasympathetic preganglionic neurons leave cranial nerves
via named branches to reach parasympathetic ganglia in the head, neck, thorax and abdomen
53
Preganglionic neurons leave the S2-S4 spinal nerves to reach
parasympathetic ganglia in the pelvis
54
Shoulder girdle (pectoral girdle)
Between the axial skeleton and shoulder joint
55
Flexión
Decrease angle
56
Extensión
Increase angle
57
Abduction
Away from midline/body
58
Adduction
“Add” to body
Toward midline
59
Medial rotation
Towards midline
60
Lateral rotation
Move away from midline
61
Circumduction
Distal moves in circle
Ex. Windmill w arm
62
Supination
Palm facing upward
Like holding a bowl of soup
63
Pronation
Face downward
64
Insertions
more mobile and/or the more distal of a muscle's attachments
Moves w contraction
65
Coracoid process (crow’s beak) [scapula]
major point of weight/stress transfer from
the arm to the shoulder; it also helps shelter the superior aspect of the
shoulder joint
Process=muscles attach to it
66
Shoulder separation
Tearing of the ligaments connecting the distal end of the clavicle to the lateral end of the scapula
Dislocation of the AC joint (acromioclavicular)
67
Coracoclavicular ligament
Coracoid to clavicle
68
Acromioclavicular ligament
Acriomion to clavicle
69
Coracoacromial ligament
Coracoid to acromion
70
Major actions of pectoralis major
Adduction and medial rotation of the arm
71
Importance of pectoralis minor
stabilizes scapula against thoracic wall; medial rotation of scapula
important landmark for axillary artery
can function as an accessory muscle of respiration
72
Importance of Serratus anterior
important in stabilization of scapula by holding it against thorax
required for lateral scapular rotation to abduct the arm beyond 90˚
damage to muscle or innervating nerve results in scapular winging
73
Trapezius actions
Elevates, depresses, retracts and
rotates scapula
74
Latissimus dorsi
Extends, adducts, and medically rotates humerus
Lady between two majors
75
Levator scapulae
Elevates and medically rotates the scapula
76
Rhomboid minor role
Retracts and medially rotates scapula;
stabilizes scapula
77
Rhomboid major role
Retracts and medially rotates scapula
78
Deltoid influence
major abductor of humerus from 15˚-90˚; the
different parts of the deltoid muscle actually allow it
to do all actions except adduction
79
Rotator cuff muscles
Supraspinatus, infraspinatus, teres minor, Subscapularis
80
Shoulder joint
a ball and socket joint with articulation between the glenoid cavity and the head of the humerus.
81
Movements at a shoulder joint
1. Abduction / Adduction
2. Flexion / Extension
3. Medial Rotation / Lateral Rotation
4. Circumduction
82
Full range of movement at the shoulder depends on
Glenohumeral joint movement
2. Sternoclavicular joint movement
3. Acromioclavicular joint movement
4. Scapular rotation
83
What limits pure abduction of the arm to 90 degrees
Acromion
84
When is the deltoid effective
Only after initiation by the supraspinatus
85
How to abduct above 90 degrees
Abduction of the arm above 90° requires scapular rotation.
a. lateral rotation
i. tilting of the scapula such that the inferior angle moves away from
the vertebral column
ii. glenoid cavity tilts upward via serratus anterior and trapezius muscles
b. medial rotation
i. tilting of the scapula such that the inferior angle moves toward the vertebral column
ii. glenoid cavity tilts downward via the rhomboid major and minor, pectoralis minor, levator scapulae, and trapezius muscles
86
Primary biomechanical role of the rotator cuff is to
stabilize the glenohumeral joint by compressing the humeral head against the glenoid fossa
87
How are the rotator cuff muscles dynamic stabilizers
maintaining the head of the humerus in the glenoid fossa during these movements of abduction and rotation
88
Where are the supraspinatus tendon along with other rotator cuff tendons uniquely susceptible to compression
in the small subacromial space between the acromion and the humerus
89
Where does shoulder dislocation almost always occur and what damage could it cause
almost always occurs in the inferior direction because the joint capsule is not reinforced inferiorly. Dislocation can result in damage to the axillary artery and nerve.
90
How to test the deltoid
Resisted abduction of arm at 90 degrees
91
Test supraspinatus
Resisted initial abduction
92
Test infraspinatus
Resisted lateral rotation
93
Test Subscapularis
Resisted medial rotation; or lift off test
94
Test latissimus dorsi
Resisted arm extension with arm in medial rotation
95
Test rotator cuff (especially supraspinatus)
Inverted can test
1. Specific for supraspinatus impingement or tendonitis
96
Axilla conveys
neurovascular structures from the neck to the upper limb
97
Boundaries of axilla
1. Anterior—clavicle and pectoral muscles
2. Posterior—scapula and subscapularis muscle
3. Medial—serratus anterior muscle
4. Lateral—humerus
98
Contents of axilla
1. Axillary artery
2. Axillary vein
3. Brachial plexus
4. Long head of the biceps brachii muscle
5. Short head of the biceps brachii muscle
6. Coracobrachialis muscle
99
Axillary artery length
Extends from 1st rib to inferior margin of teres major muscle
100
What divides the axillary artery into 3 parts
Divided by pectoralis minor m
101
First part of axillary artery
i. ii. proximal to the pectoralis minor muscle\
superior thoracic artery to the 1st / 2nd intercostal spaces (small)
102
2nd part of axillary artery
posterior to the pectoralis minor muscle
thoracoacromial trunk with branches to shoulder, acromion, deltoid, clavicle, and pectoral muscles
lateral thoracic artery (highly variable) to breast and lateral chest wall
103
3rd part of axillary artery
i. ii. distal to the pectoralis minor muscle
subscapular artery (largest branch of the axillary artery) divides into
the thoracodorsal and circumflex scapular arteries
iii. anterior humeral circumflex artery (sometimes absent)
iv. posterior humeral circumflex artery (usually larger than its anterior
partner)
104
Axillary vein
—drains blood from the upper limb. Formed by the junction of the paired
brachial veins and the basilic vein near the inferior border of the teres major muscle.
105
Brachial plexus provides
sensory and motor innervation to the upper limb. Allows common nerve
roots to come together in peripheral nerves to allow for synergistic function of
multiple muscles to act in unison for smooth movements.
106
Brachial plexus is derived from
Ventral rami of spinal nerves C5-T1
107
Plan of brachial plexus
5 roots (rami) consisting of ventral rami from C5-T1 unite to form trunks
3 trunks (upper, middle, lower), which bifurcate to form divisions
6 divisions (3 anterior, 3 posterior), which unite to form cords
3 cords (lateral, medial, posterior)
5 big nerves, plus numerous smaller ones
108
What do the 3 anterior divisions of the brachial plexus supply
Supply flexors via the lateral and medial cords
109
What do the 3 posterior divisions supply
Extensors via the posterior cord
110
Brachial plexus components: relationships to structures in the neck and axilla
a. 5 roots lie between the anterior and middle scalene muscles
b. 3 trunks cross the posterior triangle of the neck
c. 6 divisions pass posterior to the clavicle
d. 3 cords surround the second part of the axillary artery, posterior to the pectoralis
minor muscle
111
Axillary nerve
is found in the axilla, hence the name. It passes around the surgical
neck of the humerus and innervates the deltoid and teres minor muscles. It also
supplies a small patch of skin over the shoulder with sensation.
112
Radial nerve
radial nerve is found on the radial (lateral) side of the forearm (i.e., where the
radius is relative to anatomical position), hence the name. It travels around the shaft
of the humerus to innervate the muscles of the posterior compartments of both the arm
and forearm. It also supplies much of the skin over the posterior arm, forearm, and
the dorsum of the hand with sensation.
113
Musculocutaneous nerve
travels through the coracobrachialis muscle and
innervates the muscles of the anterior compartment of the arm. It continues as a cutaneous nerve to the lateral side of the forearm (the lateral cutaneous nerve of the forearm), hence the name.
114
Median nerve
median nerve has no branches in the arm but is the principal nerve to the muscles
of the anterior compartment of the forearm and the thumb. It travels down the middle
of the limb (like a median strip on a highway), hence the name. The median nerve
supplies the index and middle fingers, the palmar surface of the thumb, and most of
the palm with sensation (see figure on p. 65).
115
Ulnar nerve
innervates some of the forearm muscles; however, it is the primary
nerve to the small muscles found in the hand. It travels along the ulnar side of the
forearm, hence the name. It supplies the skin on the ulnar (medial) side of the hand,
as well as the little finger and the ulnar side of the ring finger with sensation
116
Axillary nerve pairs with
Posterior humeral circumflex artery
• can be damaged by shoulder dislocation and surgical neck fractures
117
Radial nerve pairs with
—Deep brachial artery
• can be damaged by humeral shaft fractures
118
At what joints do supination and pronation take place
Radioulnar joints
119
Muscles of the anterior flexor compartment of the forearm act on the
elbow, radioulnar, wrist, metacarpophalangeal (MP) and interphalangeal (IP) joints.
120
Coracobrachialis m, biceps brachii m, brachialis m (all anterior flexor muscles) are innervated by
All innervated by musculocutaneous n
121
Posterior (extensor) compartment innervated by
Radial n
122
Action of triceps brachii
action—crosses the shoulder
and elbow joints; extends the
forearm; the long head also
stabilizes the abducted
humerus
123
Axillary/brachial artery
—runs from about the midpoint of the clavicle to the midpoint of the cubital fossa, then divides into radial and ulnar arteries opposite the radial neck. The brachial artery gives off the deep brachial (profunda brachii) artery, which accompanies the
radial nerve.
124
Cephalic vein
—superficial vein that drains the lateral side of the upper limb; joins axillary vein in deltopectoral triangle.
125
Basílic vein
superficial vein that drains the medial side of the upper limb and joins the
distal part of the brachial veins to form the axillary vein.
126
Cephalic and basilic veins drain the
Skin and subcutaneous tissue. The muscles are
drained by the brachial veins, paired deep veins that accompany the brachial artery.
127
Collateral ligaments
Help reinforce hinge joints medially and laterally
128
Bones of elbow joint
Bones Comprising the Elbow Joint
1. humerus—epicondyles, and condyles
(capitulum and trochlea)
2. radius—radial head and radial tuberosity
3. ulna—trochlear notch, radial notch, and
coronoid and olecranon processes
129
Actions shared in proximal radioulnary joint and humeroradial joint
Most important for pronation/supination
130
Ulnar collateral and radial collateral ligaments—
Ulnar collateral and radial collateral ligaments—restrict movement across the
humeroulnar joint. Collateral ligaments, in general, prevent side-to-side deviation and
rotation of a hinge joint thus permitting only flexion/extension. Tommy John surgery-
reconstruction of a torn ulnar collateral ligament.
131
Annular ligament
converts the radial notch into a pivot joint in which the radial head
rotates during pronation/supination. Nursemaid's elbow is a partial dislocation of the
radial head.
132
Funny bone
Medial epicondyle of humerus
Common flexor origin
133
Lateral epicondyle of the humerus
Common extensor origin
134
What can dislocation cause for the elbow and around
cause damage to the structures passing through and around the elbow: the brachial
artery and vein, and the ulnar, median and radial nerves,
135
Overview and innervation of anterior (flexor) compartment
flexors and pronators, mostly innervated by the
median nerve, some by the ulnar nerve
Common origin of medial epicondyle
136
Posterior extensor compartment innervation
extensors, all innervated by the radial nerve
137
Superficial layer of anterior forearm
Radial to ulnar side
Pronator teres
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnaris
138
Middle layer of anterior compartment
Flexor digitorum superficialis
139
Deep layer of anterior flexor compartment
Flexor pollicis longus
Flexor digitorum profundus
Pronator quadratus
140
Radial artery supplies the
Lateral forearm, passes through the anatomical snuffbox and joins the ulnar artery forming the deep palmar arterial arch, an important source of collateral circulation in the hand
141
Ulnar artery travels
With the ulnar nerve
It gives off the common interosseous artery, which branches into the anterior and posterior interosseous arteries that supply the deep muscles of the forearm.
The ulnar artery joins the radial artery in the hand to form the superficial palmar
arterial arch.
142
Median nerve
Innervates all but 1½ muscles of the flexor
compartment of the forearm. Passes between
the heads of the pronator teres muscle. Descends
deep to flexor digitorum superficialis (FDS) on the
radial side, then passes deep to the flexor retinaculum (into the carpal tunnel).
143
Ulnar nerve
Passes posterior to the medial epicondyle (funny
bone), then between the FCU and the FDP.
Innervates flexor carpi ulnaris (FCU) and the ulnar
half of flexor digitorum profundus (FDP) that flexes digits 4 and 5.
144
NEITHER the median nor the ulnar nerves innervate
Structures above the elbow joint
145
Posterior compartment
Contains extensors and supinators innervated by branches of the radial nerve. A major function of wrist extensors is to enhance the gripping power of the hand.
146
Superficial layer of posterior compartment
Brachioradialis, extensor carpi radialis longus, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi, extensor carpi ulnaris
147
Will damage to the radial nerve at or below the elbow impair their innervation? [brachioradialis and extensor carpi radialis longus]
NO, brachioradialis and extensor carpi radialis longus muscles receive their innervation directly from the radial nerve, ABOVE THE ELBOW
148
Deep layer of posterior forearm
Supinador
Abductor pollicis longus
Extensor pollicis brevis
Extensor pollicis longus
Extensor indicis
149
Posterior interosseous nerve innervating abductor pollicis longus
a continuation of the
deep branch of the
radial nerve after it
passes through the
supinator muscle
150
Posterior interosseous nerve innervates which m
Extensor digitorum
Extensor digiti minimi
Extensor carpi ulnaris
Abductor pollicis longus
Extensor pollicis brevis
Extensor pollicis longus
Extensor indicis
151
All of the muscles in the posterior compartment of the forearm (and arm) are innervated by
Radial nerve or its branches
152
Where does the radial nerve enter the forearm
the flexor side of the elbow, between the brachialis
and brachioradialis. It directly innervates brachioradialis and extensor carpi
radialis longus muscles
B. Divides into superficial branch and deep branch near elbow.
153
Superficial branch of the radial nerve
travels deep to the
brachioradialis to a point near the wrist where it continues to supply the skin
over the radial half of the dorsum of the hand.
154
Deep branch of radial nerve
deep branch innervates extensor carpi radialis brevis and then enters,
and innervates, the supinator
After passing through supinator, the deep branch is re-named the posterior
interosseous nerve, which innervates the rest of the extensor muscles
155
When does the deep radial nerve change name
Called posterior interosseous nerve when it exits the supinator
156
How can the radial nerve be injured
radial nerve can be injured
by the jagged edges of a broken humerus (recall
that it wraps around the shaft of the humerus), by
deep trauma, or by compression. Compression of
the radial nerve can result from improper use of a
tourniquet, or from resting one's arm over the back
of a chair ("Saturday night palsy"). Inflammation of
the supinator (e.g., from overuse of a screwdriver)
can also compress the deep branch of the radial
nerve. Since the radial nerve supplies all of the
wrist extensors, loss of this nerve in the arm results
in "wrist drop."
157
Radial nerve damage results in
Wrist extension lost
Lose grip strength
158
Posterior interosseous artery
a. the ulnar artery gives off the common interosseous artery, which branches into
the anterior and posterior interosseous arteries
b. the posterior interosseous artery then supplies superficial and deep muscles of
the posterior compartment
159
Metacarpophalangeal (MP) joints
Joints found at the knuckles
Flexión, extension, abduction, adduction take place here
Adduction and abduction in reference to the middle finger
160
Interphalangeal joints (IP)
We can flex them and extend them.
"PIP" refers to the proximal IP joint, and "DIP" refers to the distal IP joint.
161
Most common injury on the radial side of wrist ligaments
most common injury on the radial side is to the ligaments connecting the
lunate with the scaphoid, including the scapholunate ligament.
162
Most common injury on the ulnar side of wrist ligaments
on the ulnar side is to the ligaments of the triangular
fibrocartilaginous complex (TFCC), which keeps the radius and ulna stable as
the hand grasps an object or the forearm rotates.
163
Which carpal bone is most commonly fractured
Scaphoid (beware avascular
necrosis and poor healing).
164
Which carpal bone is most frequently DISLOCATED
Lunate (beware median nerve)
165
Anatomical snuff box
i. triangular depression at the root of
the thumb bounded by the tendons of
the abductor pollicis longus and
extensor pollicis brevis muscles
laterally, and the extensor pollicis
longus muscle medially
ii. contains the radial artery and the
scaphoid bone
iii. tender to palpation with scaphoid
fractures (“snuffbox tenderness”)
166
Compartments of intrinsic muscles of the hand
1) the thenar compartment, 2) the central compartment, and 3) the hypothenar compartment. The 3 muscles of the thenar compartment act on the thumb and are innervated by the median nerve. The muscles of the central compartment act on the MP and IP joints. Most are innervated by the ulnar
nerve. The muscles of the hypothenar compartment act on the little finger and
are innervated by the ulnar nerve.
167
Dorsal interossei
1. 4 muscles that arise by double heads from adjacent
metacarpal bone
2. FLEX MP joints and EXTEND IP joints—this is due to their
insertion into the extensor expansions of digits 2-4
3. ABDUCT their respective digits
4. innervation—ulnar nerve
168
Palmar interossei
1. 3 muscles arising by single heads from metacarpals 2, 4 and 5
2. cross their respective MP joints to insert into the
extensor expansions of their respective digits
3. like the dorsal interossei, they FLEX MP joints and
EXTEND IP joints
4. unlike the dorsal interossei, they ADDUCT their
respective digits
5. innervation—ulnar nerve
169
Lumbricals
4 muscles arising from the tendons of the flexor digitorum profundus muscle
cross their respective MP joints to insert into the extensor expansions of digits 2-5
FLEX MP joints and EXTEND IP joints
innervation—median nerve (lateral two lumbricals) and ulnar nerve (medial two)
170
Extensor tendinous expansions
comprised of the distal ends of the extensor digitorum communis tendons
receive insertions of lumbricals and interossei
effectively carry the insertions of the interossei and lumbricals from ventral to the MP
joints, to dorsal to the IP joints
171
Adductor pollicis
1. origin/insertion— has transverse and oblique heads that originate from 2nd and 3rd
metacarpals and insert on the ulnar side of the proximal phalanx of the thumb
2. action—assists opponens pollicis; grip power
3. innervation—ulnar nerve
172
How many different motor nerves are needed for full digital extension
1. radial nerve to extend the MP joints and help with IP extension
2. ulnar and median nerves to extend all of the IP joints
173
Thenar compartment innervated by
Recurrent branch of median nerve
174
Abductor pollicis brevis
origin—lateral carpal bones
insertion—1st phalanx
action—abduction; assists with opposition
innervation—recurrent branch of median nerve
175
Flexor pollicis brevis
origin—trapezium
insertion—1st phalanx
action—flexion; assists with opposition
innervation—recurrent branch of median nerve
176
Opponens pollicis
origin—trapezium
insertion—lateral side of 1st metacarpal
action—opposition
innervation—recurrent branch of median nerve
177
What happens if the opponents pollicis muscle becomes dysfunctional
The majority of the use of the hand is
lost if the opponens pollicis muscle becomes
dysfunctional.
178
Hypothenar eminence
contains 3 muscles, all
innervated by the ulnar nerve.
1. abductor digiti minimi
2. flexor digiti minimi
3. opponens digiti minimi
179
Superficial palmar arterial arch
a. fed primarily by the ulnar artery
b. gives origin to the palmar digital arteries
180
Deep palmar arterial arch
a. fed primarily by the radial artery
b. lies proximal to the superficial arch
c. lies within the same plane as the motor
branches of the ulnar nerve
181
What does the Allen test demonstrate
How the presence of the two arterial arches provides important collateral blood flow to the hand
182
Median nerve supply to
a. enters the hand by passing through the carpal tunnel
B. provides motor innervation to 5 of the intrinsic muscles in the hand
i. 3 thenar muscles
ii. 2 radial lumbricals
c. provides cutaneous innervation to the radial 3½ digits; cutaneous branches travel
with the palmar digital arteries
183
Ulnar nerve
enters the palm by crossing superficial to the flexor retinaculum
provides motor innervation to all of the intrinsic muscles of the hand except for the 5 innervated by the median nerve
provides cutaneous innervation to the palmar surface of the medial 1½ digits
184
Dermatomes
areas of skin receiving cutaneous innervation from a single dorsal root.
185
Axillary nerve (C5, C6) SENSORY DISTRIBUTION
Lateral proximal arm
186
Sensory distribution of musculocutaneous nerve C5,C6
Anterior and lateral forearm
187
Sensory distribution of radial nerve C5-C8, T1
posterior arm and forearm
1st web space
dorsal aspect of radial 2 ½ fingers
188
Sensory distribution of median nerve C6-C8, T1
Radial surface of palm
palmar aspect of radial 3 ½ fingers
189
Ulnar nerve C8-T1
ulnar aspect of palm
palmar aspect of ulnar 1 ½ fingers
dorsal aspect of ulnar 2 ½ fingers
190
What type of lesion would involve multiple dermatomes
Nerve root lesions always involve a single dermatome, while peripheral nerve or
plexus lesions may involve multiple dermatomes.
191
Where do you test for median nerve for sensation
Tips of fingers 1-3
192
Flexor retinaculum helps form what
A roof over the carpal groove to form a tunnel that transmits 9 tendons (FDS, FDP, FPL) and their synovial sheathes, as well as MEDIAN NERVE as they cross the wrist
193
Carpal tunnel syndrome
result in inflammation of these tendons and
compression of the median nerve to produce:
- pain with finger and wrist flexion/extension
- burning sensation and numbness over the palmar surface of the radial 3 ½ digits
- weakness and atrophy of the thenar muscles
194
Phalen test
Requires the patient to flex their wrists fully and hold the position for about 30-60 seconds.
A positive result is when the patient experiences numbness or tingling in the fingers
Not pinky
195
Tinel test
Involves gently tapping over the median nerve at the wrist.
A positive result is when tapping produces a tingling sensation in the fingers.
196
Curvature of cervical and lumbar regions
Cervical and lumbar regions are concave posteriorly
Also convex anteriorly
197
Curvature of thoracic and sacral regions
Concave anteriorly
Convex posteriorly
198
Kyphosis
Kyphosis—excessive posterior convex curvature, usually in thoracic region
199
Lordosis
excessive lumbar curvature, often due to obesity or pregnancy
200
Scoliosis
excessive lateral curvature, onset most commonly in adolescents
201
Vertebrae
7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 4 coccygeal
202
Pedicles are indented to form
Vertebral notches, which align with those of adjacent vertebrae to form intervertebral foramina
203
Spinous processes
For attachment of ligaments and muscles
204
Transverse processes
levers for muscle attachment
205
Articular processes
Superior and inferior articular facets
206
Spina bífida
a defect in the vertebral arch; most severe forms can include the spinal meninges or even the spinal cord itself.
207
What foramen do just cervical vertebrae have and what passes through
Transverse foramina for vertebral artery
208
C1 (atlas)
C1 (atlas)—superior facets articulate with occipital condyles; no body
209
C2 (axis)
C2 (axis)—dens extends superiorly from body
210
What facets are unique to thoracic vertebrae
costal facets for articulation with ribs
211
Unique for sacrum
5 fused vertebra
i. transmit body weight to pelvic girdle via sacroiliac joint
ii. median sacral crest—formed by fused sacral spines
iii. sacral cornua—inferior articular processes of S5
iv. anterior and posterior sacral foramina—transmit ventral and dorsal
primary rami of sacral spinal nerves
v. sacral hiatus—area where lamina over S5 is absent
212
Anterior longitudinal ligamento
—covers the bodies and intervertebral discs; also
prevents hyperextension
213
Posterior longitudinal ligamento
Posterior longitudinal ligament—limits hyperflexion and posterior disc protrusion
214
Ligamentum flavum
Strongest ligament, located between adjacent laminae; limits
separation of the laminae during flexion, and assists in extension back to the
anatomical position
215
Intervertebral disc: annulus fibrosus
fibrocartilage layers running obliquely between adjacent
vertebral bodies
216
Nucleus pulposus
Highly elastic central core
217
If an intervertebral disc herniates, where does it go most often
usually protrudes posterolaterally due to the strength of the posterior
longitudinal ligament. If it protrudes posteriorly, it could compress the spinal
cord (but remember, the spinal cord ends at the level of the intervertebral disc
between the 1st and 2nd lumbar vertebrae)
218
Facet joints
Between inferior articular process of superior vertebrae, and superior articular
process of inferior vertebra. Limits flexion, extension, and rotation. Limits anterior
and posterior displacement of adjacent vertebrae.
b. Often affected in osteoarthritis
219
Atlantooccipital joint
a. Between C1 superior articular facet and occipital condyles
b. Allows flexion and extension (nodding “yes”)
220
Atlantoaxial joint
a. Allows skull and C1 to rotate as a unit on C2 (“no”).
b. Rotation between dens of axis and anterior arch of atlas. Dens held in place by
transverse ligament of atlas. Rotation and side-to-side head movement limited by
strong alar ligaments from dens to lateral margins of foramen magnum. Rotation of
45º at atlantoaxial joint and another 45º at the rest of the cervical vertebrae
221
Sacroiliac joint
very strong synovial joint suspending the sacrum between the ilia
a. Ligaments
i. interosseous sacroiliac—massive ligament
ii. anterior and posterior sacroiliac
b. Functions to transmit body weight from sacrum to ileum and then to the femur when
standing or the ischial tuberosities when sitting.
222
Movements of the vertebral column are result of
Movements of the vertebral column are the result of gravity, abdominal muscles, and the
muscles of the back. There are two groups of back muscles: extrinsic muscles and intrinsic
muscles.
223
Extrinsic back muscles
The extrinsic muscles are the back muscles that help to anchor the upper limb to the axial skeleton. They include the trapezius, latissimus dorsi, rhomboids, and the levator
scapula.
224
Where is most of the body weight in respect to the vertebral column
Body weight is anterior to the vertebral column
225
Erector spinae muscles
largest of the deep back muscles and are located in the intermediate layer of the back. They extend from the base of the skull to the pelvis, and are made up of the longissimus, iliocostalis, and spinalis muscles. The erector spinae muscles laterally bend and extend the back.
common origin from a
broad tendon attached to the posterior part of
the iliac crest, sacrum, sacroiliac ligaments,
and lumbosacral spines.
226
Distal attachments of erector spinae m
They have distal attachments on the spines and
transverse processes of the vertebrae, ribs, and
base of the skull.
227
Bilateral contraction of the erector spinae muscles causes
back and head extension. They
limit forward flexion of the thorax, which can
occur secondary to gravity
228
Unilateral contraction causes
Ipsilateral side flexión and rotation of the vertebral column and head
229
Movements of the Vertebral Column: flexión
—rectus abdominis, iliopsoas, scalenes and sternocleidomastoid muscles
230
Extensión
erector spinae muscles,
after initiation with gluteus maximus
and hamstring muscles
231
Lateral bending
Erector spinae, abdominal obliques, quadratus
lumborum and psoas major muscles
232
Rotation
erector spinae and deep neck
muscles
233
Where does each non floating rib articulate with the transverse process or the corresponding vertebrae
Costotransverse joint
A synovial plane joint
234
3 parts of sternum
manubrium, body, and xiphoid process.
235
Level of manubrium
manubrium lies at the level of the
third and fourth thoracic vertebrae (T3 and T4
Both the
clavicle and the first rib articulate with
the manubrium. The joint between the
manubrium and the body is called the
manubriosternal joint. FORMS THE STERNAL ANGLE
236
Sternal angle importance
important
landmark for the level of the disc
between T4 and T5 and is also the level
of the second rib.
237
Xiphoid process in younger vs older ppl
process is cartilaginous in younger people and ossified in older people.
238
Rib count
12
239
What vertebrae do ribs articulate w
Each rib articulates posteriorly with two thoracic vertebrae; by the costovertebral joint. An exception to this rule is that the first rib articulates with the
first thoracic vertebra only.
240
Parts of the rib
• Head with two articular facets for adjacent vertebral bodies
• Tubercle for articulation with a transverse costal facet
• Neck
• Shaft
• Costal groove- containing intercostal nerves and vessels
241
False ribs
Ribs 8 (usually), 9, and 10 are false ribs
because they are attached to the rib found just superior, and not directly to the sternum.
242
Costal groove
helps protect the intercostal nerve and vessels
243
Costal cartilage
Ribs attached to the sternum or to each other by costal cartilage
244
External intercostal muscles
Elevate the ribs, increase width of the thoracic cavity
245
Transversus thoracis
a thin, flat sheet of muscle located on the inner surface of the anterior chest wall, acting as an accessory respiratory muscle that primarily functions to depress the ribs, supporting expiration by pulling the costal cartilages of the second to sixth ribs towards the sternum during forced exhalation
An INNERMOST INTERCOSTAL MUSCLE
246
Intercostal vein, artery, and nerve run
internal intercostal muscle layer and
the innermost intercostal muscles (if present) are the intercostal vein, artery and nerve.
These are usually running near the inferior margin of the rib, either in or near the costal
groove.
247
Diaphragm
musculotendinous
structure that separates the thoracic and
abdominal cavities. It is attached to the
inferior ribs, and the thoracic vertebrae.
When the diaphragm contracts, it
descends because its muscle fibers shorten,
pulling the central tendon downwards
248
Diaphragm during inspiration
descends during inspiration,
increasing the superior-inferior dimension of
the thoracic cavity.
249
What innervates the diaphragm
Phrenic nerve
250
How do spinal nerves exit the vertebral column
Through the intervertebral foramina
251
Dorsal primary rami carry
afferent sensory fibers (e.g., touch, temperature, etc.) from the skin and joints of the back, and efferent motor fibers to muscles of the back.
252
Which ventral primary rami become the intercostal nerves
In the thorax (T1-T11),
the ventral primary rami become the intercostal nerves (T12 becomes the subcostal nerve) that
run along the inferior margin of each rib in the intercostal space
253
What do the intercostal nerves supply
nerves supply the muscles listed above and are also sensory to the strip of skin overlying each intercostal space.
254
Thoracic wall is supplied by the
posterior intercostal arteries and the anterior intercostal arteries
255
Posterior intercostal arteries are branches of
Of the aorta
They follow the intercostal
nerves in the intercostal spaces
256
Anterior intercostal arteries are branches of
Internal thoracic arteries
run laterally and eventually anastomose—the fusion of vessels, often
at level of capillaries—with the posterior intercostal arteries. The anterior intercostal arteries
supply the breasts as well as the muscles and fascia of the anterior thorax.
257
Internal thoracic arteries run
run on either side of the sternum along the inner surface of the thoracic wall. They continue into the abdominal wall as the superior epigastric arteries.
They are branches of the subclavian arteries.
258
Where do the mammary glands develop
develop between the pectoralis
major muscle (and parts of the
serratus anterior muscle) and the
skin.
259
Axillary tail
wing-like
lateral projection of mammary
gland
260
What is most of the volume of the breast
Most of the volume of
the breast is instead occupied by
fat and the suspensory ligaments
that anchor the breast to
underlying deep fascia
261
Axillary lymph nodes
Most of the breast's lymphatics drain into the axillary lymph nodes.
Breast cancers can be successfully treated by
lumpectomy—surgical excision of the cancerous tissue. Radical mastectomy, which involves
removing the entire breast, underlying pectoral muscles, and all lymph nodes, is now rare.
262
Visceral pleura
inner layer closely enveloping the lung
INSENSITIVE to PAIN
263
Parietal pleura
Outer layer
Richly innervated
264
Pleural cavity
filled with a layer of pleural fluid. The pleurae reduce friction during respiration. The
pleural cavity is a potential space. Due to forces between the two layers, there is
negative pressure in the pleural cavity. The negative pressure creates an outward pull
on the lungs that keeps them inflated.
265
Diaphragmatic pleura and mediastinal pleura
parietal pleura overlying the diaphragm and mediastinum, respectively—are innervated by branches of the phrenic nerve (formed from the ventral primary rami of C3, C4, and C5).
266
Costal pleura innervation
the parietal pleura underlying the ribs—is innervated by branches of the intercostal nerves.
267
Pneumothorax
occurs when air leaks into the pleural space, the area between the lung and chest wall
To fix: Go to mid clavicular line and go to 2nd intercostal muscles and puncture though , leave catheter and suck air out
Put it in plural cavity
Don’t want to go too far down and hit the heart
268
Root of lungs
bundle of structures that enter and leave the lung; they do so at a point called the
hilum
269
Divisions of left lung
left lung is usually divided into a superior lobe and an inferior lobe by the oblique fissure
left lung also has a distinctive cardiac notch in its
anterior margin.
270
Divisions off right lung
usually divided into a superior, middle
and inferior lobe by a horizontal fissure and an oblique fissure.
271
What would happen w trauma to the neck
(e.g., a stab wound) can damage
the pleura and lung, leading to
direct communication between
the atmosphere and the pleural
cavity.
272
What do the roots contain
contain the primary bronchi and pulmonary
vessels, connective tissue, nerves, and
lymphatics. The primary bronchi branch
regularly after entering the hilum, sending a
secondary bronchus to each lobe.
273
Tertiary bronchi
Supply specific regions of the lungs
274
Blood from right ventricle is pumped through
Right and left pulmonary arteries
GO TO THE LUNGS via the root
DEOXYGENATED
275
The superior pulmonary vein and inferior pulmonary vein…
Exit each lunch (oxygenated) and enter the LEFT atrium
276
Where would aspirated objects tend to lodge and why
right primary bronchus is shorter, wider, and more vertical
than the left. Therefore, aspirated objects tend to lodge in the middle or inferior lobes
of the right lung.
277
Innervation of the lungs
receive parasympathetic innervation via the vagus nerve (CN X). These
fibers are motor to the smooth muscles of the bronchi (bronchoconstrictors), inhibitory
to the muscles of blood vessel walls (vasodilators), and cause the glands of the bronchi
to secrete fluid and mucus. Sympathetic innervation to the lungs (from the sympathetic
chain) inhibits bronchiolar smooth muscle contraction (bronchodilators) and the
secretion of pulmonary glands, and is motor to pulmonary vasculature
(vasoconstrictors)
278
Pulmonary thromboembolism
result of an obstruction (e.g., a clot, plaque, or air) blocking a pulmonary artery. If
a major artery is blocked, death can be very rapid
279
Pericardium
double-walled fibrous sac that encloses the heart and the roots of the
great vessels. It occupies most of the middle mediastinum, and functions to maintain the
position of the heart and protect it from overfilling
280
Fibrous layer of pericardium
tough fibrous layer closed by attachment to the great vessels; it
blends with the central tendon of the diaphragm.
281
Serous layer
smooth inner sac with lubricated surfaces that allow movement.
Parietal layer—lines the inner surface of the fibrous pericardium
Visceral layer—covers the entire surface of the heart
The potential space between the parietal and visceral layers of the serous
pericardium is the pericardial cavity
282
Pericarditis
inflammation of the pericardium. It causes substernal pain
and produces pericardial effusion
283
Cardiac tamponade
Cardiac Tamponade—effusion that impairs cardiac filling, resulting in
circulatory failure. Treatment is by pericardiocentesis.
284
How does fibrous pericardium help
Doesn’t allow the heart to expand too much
285
How does the foramen ovale close in newborns
Fossa oval is closes postnatally due to increased pressure in left atrium
286
Right atrium
- receives venous blood from the superior vena cava (SVC), inferior vena cava
(IVC), and coronary sinus
- coronary sinus—returns much of the venous blood from the heart itself to
the right atrium; lies in the posterior part of the coronary groove
- auricle—blind pocket, overlying the ascending aorta
-Pectinate muscle- ridges of muscles are located in the inner walls of both
atria.
287
Pectinate m
Pectinate muscle- ridges of muscles are located in the inner walls of both
atria. They are shaped like the teeth of a comb, and the term comes from the
Latin word pecten, which means comb. They function to strengthen the
atrial walls, accommodate increased venous return, and act as a substrate
for conduction pathways that ensure the atria contract in a coordinated way.
288
Interatrial septum
a. fossa ovalis—oval depression where the septum is thin. This is the site of
the foramen ovale in the fetus.
b. Clinical Condition: an atrial septal defect (ASD) can allow blood to shunt
from the left to the right side of the heart
289
Left atrium
forms most of the base of the heart
receives the openings of the 4 pulmonary veins from the lungs
left auricle forms the superior part of the left border of the heart
Clinical Condition: thrombi (blood clots) form on the walls of the left atrium
in certain types of heart disease
290
Trabeculae carnea
irregular bundles of muscle projecting on the inner
surface. Function somewhat controversial, but probably affect structural
support and compliance.
291
Atrioventricular (AV) valves
i. right AV valve = tricuspid valve
ii. left AV valve = bicuspid (mitral) valve
292
Atrial septal defect
There’s a whole in the wall between atria and oxygenated blood goes back to the lungs
Not needed so now extra work is being done
293
Papillary muscles
The papillary muscles contract during heart contraction, pulling on the chordae tendineae, which are connected to the valve leaflets. This tension helps prevent the atrioventricular (AV) valves (mitral and tricuspid) from prolapsing into the atria. In essence, the papillary muscles help keep the valves closed tightly, preventing blood from flowing backward.
294
Right ventricle
Forms most of the ANTERIOR SURFACE and almost all of inferior border
295
Right AV (tricuspid) valve
i. cusps—3 fibrous cusps are attached to the annulus fibrosis (a fibrous ring around both atrioventricular orifices)
ii. papillary muscles—conical projections into cavity. Papillary muscles contract prior to and during contraction of the right ventricle.
As ventricular size decreases (from ventricular contraction), the contraction of papillary muscles, attached to the AV valve cusps by chordae tendineae, prevents the cusps from prolapsing into the right
atrium.
iii. chordae tendineae—small tendinous bands that connect the valve cusps to the papillary muscles.
296
Pulmonary valve stenosis
Pulmonary valve stenosis is a condition where the pulmonary valve, which controls blood flow from the right ventricle to the lungs, becomes narrowed. This narrowing obstructs the flow of blood, causing the right ventricle to work harder to pump blood through the valve. It can lead to symptoms like shortness of breath, fatigue, or chest pain, and in severe cases, it may cause right-sided heart failure.
297
Interventricular septum
- position corresponds to interventricular grooves on the surface
- membranous part—thin upper part near atrium
c. muscular part—thick, major part
- the membranous part is the site of the most common congenital heart defect,
a ventricular septal defect (VSD)
298
Most common site of congenital heart defect
Membranous part of interventricular septum
299
Left ventricle
- wall thickness—about 2-3 times thicker because the left ventricle contracts
against greater resistance than the RV
- Left atrioventricular (bicuspid or mitral) valve—two large sets of papillary
muscles attach to the cusps via chordae tendineae. The mitral valve is the most frequently diseased of the heart valves.
- aortic valve—3 semilunar cusps; located in the right posterosuperior part of
the LV
300
Where would the pulmonary valve be of max audibility
Left 2nd intercostal space
301
Where would the aortic valve be most audible
Right 2nd intercostal space
302
Where would the mitral valve be max audibility
Apex (5th intercostal space near the mid-clavicular line)
303
Where would the tricuspid valve be of max audibility
Lower left sternal border
304
Right coronary artery
originates in the right aortic sinus, runs in the coronary sulcus to the
back of the heart where it gives off the posterior interventricular artery, which anastomoses
with the anterior interventricular branch of the left coronary artery.
1. branches to right atrium, right ventricle, and interventricular septum
2. sinoatrial nodal artery—most common site of origin (60%)
3. right marginal branch—runs toward the apex of the heart
4. in 85% of the cases the right coronary supplies the AV node
305
Left coronary artery (and branches)
arises from the left aortic sinus and gives off a
circumflex branch and the anterior interventricular artery. It typically supplies most of the
LV, LA, interventricular septum, and some of the RV.
306
Anterior cardiac veins drain directly into the RA, what does it mean in terms of collateral circulation
direct drainage means the anterior cardiac veins don't participate in the usual collateral flow mechanisms that would normally develop if there was a blockage or narrowing in the coronary arteries. Collateral circulation helps reroute blood flow to areas of the heart that may be deprived of oxygen due to blocked arteries. Since the anterior cardiac veins don't need to engage in this process, there’s less ability to develop alternate pathways for blood drainage from the myocardium, which could be problematic in certain situations
307
Coronary sinus
—receives most veins of the heart, runs in the posterior part of the
coronary groove and ends in the right atrium. It receives the:
a. great cardiac vein—main tributary of the coronary sinus; travels with the
anterior interventricular artery
b. middle cardiac vein—travels with the posterior interventricular artery
C. small cardiac vein—travels with the marginal branch of the right coronary
308
Functional end arteries
Coronary arteries
arteries that have anastomoses with neighboring arteries, but these anastomoses are not sufficient to maintain blood flow if the artery is blocked
A sudden block thus leads to necrosis of the cardiac muscle (myocardial infarction).
309
Coronary arteriosclerosis
results in slow narrowing of the lumen of these arteries. (Coronary arteries)
310
Angina pectoris
clinical syndrome characterized by substernal discomfort
resulting from myocardial ischemia.
311
coronary
artery bypass graft (CABG).
Common surgical treatment for severe coronary arteriosclerosis
The grafted vessel is attached above and below the blocked or narrowed part of the coronary artery, allowing blood to flow around the obstruction
312
Where do postganglionic sympathetic fibers terminate
On the SA and AV nodes, and on the coronary arteries
Stimulation of the sympathetic nerves increases the heart rate and contractility
Sympathetic supply arises from the cervical and upper thoracic part
of the sympathetic trunk.
313
Where does the sympathetic supply arise
From the cervical and upper thoracic part of the sympathetic trunk
314
Refereed Cardiac pain
usually to left shoulder, and medial side of left arm,
forearm and hand; mediated by afferent nerves in the cardiac branches of the
sympathetic trunk. These afferents enter the T1-T4 spinal nerves, resulting in pain
referred to these dermatomes.
315
Is referred cardiac pain the same in men and women
pain in women can be different from men because women are more likely
to experience microvascular coronary disease, affecting smaller arteries in the heart, leading
to a wider range of symptoms like nausea, fatigue, back pain, jaw pain, and discomfort in
the upper abdomen, rather than the classic crushing chest pain often associated with men's
heart attacks; this can make diagnosis more challenging as these symptoms are often
attributed to other causes like indigestion or stress.
316
Sinoatrial (SA) node
a. natural pacemaker of the heart
b. location—junction of superior vena
cava and right atrium
c. the impulse for contraction begins at
the SA node and is conducted
throughout the atria by ordinary atrial
myocardial fibers, arriving at the AV
node
317
Atrioventricular (AV) node
Location- above the opening of the coronary sinus in the atrial septum
318
Atrioventricular bundle
passes from the AV node, divides into right & left bundle
branches that carry the depolarization to the apices of the right and left ventricles.
From there, the rest of the ventricular myocardium is depolarized by the continued
branching of the conduction bundles known as Purkinje fibers.
319
Pacemakers for
To correct arrhythmias, abnormalities in cardiac conduction rhythms
320
Electrocardiograma
passage of impulses over the heart can be amplified and recorded as an
electrocardiogram (ECG or EKG).
321
Location of mediastinum
The mediastinum is the space between the two pleural sacs. It extends from the sternum to the
vertebral column and it contains all the structures within the thoracic cavity except the lungs
and pleura.
322
Superior mediastinum
superior thoracic aperture to sternal angle (inferior border of T4)
323
Inferior mediastinum
from sternal angle to diaphragm
1. anterior mediastinum—anterior to heart and pericardium
2. middle mediastinum—pericardium and heart
3. posterior mediastinum—posterior to pericardium and diaphragm
324
Thymus
1. involved in the development of the
immune system
2. posterior to manubrium
3. involutes during puberty
4. Clinical Condition: thymoma
325
Brachiocephalic veins
a. formed posterior to medial
end of clavicle by union of
IJV and subclavian vein
b. join to form the SVC near the
right 1st costal cartilage
326
SVC
a. enters the RA in the middle
mediastinum
b. returns venous blood from everything superior to the diaphragm except
lungs and heart
327
Arch of the aorta
arches posterosuperior and to the left, anterior to the trachea,
then passes inferiorly adjacent to vertebral column. It gives off 3 branches: the
brachiocephalic trunk, left common carotid artery and left subclavian artery.
328
Pulmonary trunk
Branches into right and left pulmonary arteries
329
Vagus nerve (CN X)
a. right vagus—passes anterior to the subclavian artery, breaks up into the
pulmonary plexus posterior to the root of right lung, reforms, then breaks up
into the esophageal plexus, and gives branches to the heart and lungs.
b. left vagus—passes to the left of arch of the aorta, passes posterior to the root
of the left lung, and gives branches to the lungs, esophagus, and heart.
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Recurrent laryngeal nerves (of vagus n)
i. right—hooks under the right subclavian artery to ascend into the
neck
ii. left—hooks under the ligamentum arteriosum and aortic arch to
ascend into the neck between the trachea and esophagus
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Phrenic nerve (C3,C4,C5)
a. sole motor supply to diaphragm; sensory to pericardium, pleura
(mediastinal), parietal peritoneum, and diaphragm
b. passes anterior to the root of the lung, along the pericardium to enter the
diaphragm
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Pulmonary embolism
333
3 sensory innervation of phrenic n
Pericardium
Pleura
Peritoneum
334
Trachea
1. 2. Fibrocartilaginous tube anterior to the esophagus.
Ends by dividing into the main (primary) bronchi at the level of the sternal angle;
the dividing point is called the carina
335
Esophagus
Esophagus
1. 2. Fibromuscular tube connecting the pharynx to the stomach.
Between the trachea and vertebral column
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Thoracic (descending) aorta
1. Descends along the left side of the
vertebral column.
2. Penetrates the diaphragm at T12
(aortic hiatus) along with the
thoracic duct and the azygos vein.
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Thoracic duct
Passes upward from the abdomen
through the aortic hiatus of the
diaphragm, ascends through the
posterior mediastinum between the
aorta and the azygos vein, then
crosses posterior to the esophagus
to empty into the junction of the left
internal jugular and subclavian
veins.
2. Receives all lymph from the left
side of the head, neck and thorax,
the left upper limb, and the entire
body below the diaphragm. Lymph
returns excess interstitial fluid to
the venous system and transports
fat absorbed from the GI tract back
to the venous system.
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Azygous vein
1. Interconnects the SVC and IVC.
2. Drains the posterior thoracic and
abdominal wall and back.
3. Ascends in posterior mediastinum
to the right of the vertebral column,
then arches over the root of the right
lung to join the SVC.
4. Receives the hemiazygos vein,
which ascends on the left side of the vertebral column, and the intercostal veins
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Esophagus
1. Descends posterior to the left atrium, then through the esophageal hiatus of the
diaphragm.
2. Constricted at three regions:
a. at the arch of the aorta
b. where it is crossed by the left mainstem bronchus
c. at the esophageal hiatus
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Sympathetic trunks
Sympathetic Trunks
1. Along the lateral sides of the thoracic vertebrae.
2. Give rise to the thoracic splanchnic nerves, which pass through the diaphragm into
the abdomen.
