Rotator cuff, upper arm, brachial plexus Flashcards
1
Q
What are the 6 scapulohumeral muscles?
A
- deltoid
- teres major
- supraspinatus
- infraspinatus
- subscapularis
- teres minor
2
Q
How many parts of the deltoid muscle are there? they can act separately or together as a whole
A
3 parts
3
Q
What are the 3 parts of the deltoid muscle?
A
clavicular part
acromion part
spine of scapula part
4
Q
Where is the origin of the deltoid muscle?
A
clavicle, acromion, spine of scapula
5
Q
What does the deltoid insert onto?
A
deltoid tuberosity (humerus)
6
Q
What innervated the deltoid?
A
axillary n.
7
Q
What are the actions of the deltoid muscle?
A
-flexes and internally rotates shoulder (clavicle part)
-abducts shoulder (acromion part); becomes main abductor after supraspinatus initiates the first 15*
-extends and externally rotates shoulder (spine of scapula part)
8
Q
What is the origin of the teres major muscle?
A
inferior lateral border of the scapula and posterior inferior angle of scapula
9
Q
What is the insertion of the teres major?
A
medial lip of intertubercular sulcus of humerus (bicipital groove)
10
Q
What innervates teres major?
A
lower subscapular nerve
11
Q
What are the actions of the teres major muscle?
A
adducts and medially rotates the shoulder joint
12
Q
Along with the deltoid and rotator cuff muscles, what is an important stabilizer of the humeral head in the glenoid cavity during movement?
A
teres major
13
Q
What are the 4 muscles that make up the rotator cuff muscles (“SITS”)?
A
- supraspinatus
- infraspinatus
- teres minor
- subscapularis
14
Q
What part of the deltoid is the strongest?
A
acromion part
15
Q
The tendons of the rotator cuff muscles blend with the joint capsule of the glenohumeral joint, reinforcing it as what?
A
the musculotendinous rotator cuff protecting the joint and giving it stability
16
Q
The rotator cuff is ___________
A
Musculotendinous
17
Q
What is the origin of the supraspinatus muscle?
A
supraspinous fossa of the scapula
18
Q
What is the origin of the infraspinatus muscle?
A
infraspinous fossa of the scapula
19
Q
What is the origin of the teres minor muscle?
A
scapula
20
Q
What is the origin of the subscapularis muscle?
A
subscapular fossa
21
Q
What do the supraspinatus, infraspinatus, and teres minor muscle insert onto?
A
greater tubercle of the humerus
22
Q
What are the supraspinatus and infraspinatus muscle innervated by?
A
suprascapular nerve
23
Q
What is the insertion of the subscapularis muscle?
A
lesser tubercle of the humerus
24
Q
What is the deltoid muscle innervated by?
A
axillary nerve
25
What is the subscapularis muscle innervated by?
upper and lower subscapular nerve
26
What is the common action for the supraspinatus, infraspinatus, and teres minor muscles?
externally rotate the shoulder
27
What is the alternate action of the supraspinatus muscle besides external rotation of the shoulder?
initiates the first 15* of abduction of the shoulder
28
What is the action of the subscapularis muscle?
internal rotation of the shoulder
29
What is the most injured rotator cuff muscle?
supraspinatus muscle
30
What is the function of the rotator cuff as a unit?
1. protects and stabilizes the glenohumeral joint
2. creates stabilization with the humeral head relative to the glenoid cavity
31
What is the deltoid muscle and teres minor innervated by?
axillary nerve
32
The brachial plexus runs from what to what?
C5 to T1
33
What is defined as a group of muscles innervated by a single spinal nerve root?
myotomes
34
What is an essential part of neurological examination when suspecting radiculopathy?
myotome testing
35
What is the myotome of spinal nerve C5?
shoulder abduction and flexion
36
What is the myotome of spinal nerve C5, C6 (biceps)?
elbow flexion and forearm supination
37
What is the myotome of spinal nerve C7?
elbow extension, wrist extension, and finger extension
38
What is the myotome of spinal nerve C8?
Finger flexion
39
What is the myotome of spinal nerve T1?
Intrinsic hand muscles
40
The roots of the brachial plexus are the union of?
the ventral rami C5-T1
41
What is the superior trunk of the brachial plexus?
C5 and C6
42
What is included in the middle trunk of the brachial plexus?
C7
43
What is included in the inferior trunk of the branchial plexus?
C8 and T1
44
The superior, middle, and inferior trunk of the brachial plexus each divide into what?
An anterior and a posterior division
45
The anterior division of the brachial plexus innervates what?
anterior muscles
46
The posterior division of the brachial plexus innervates what?
posterior muscles
47
What are the names of the cords of the brachial plexus?
lateral, posterior, and medial
48
The anterior division of the upper and middle trunks unite to create what?
the lateral cord of the brachial plexus
49
The anterior division of the inferior trunk continues as what?
the medial cord of the brachial plexus
50
The posterior division of all three of the trunks unite to form what?
the posterior cord of the brachial plexus
51
What are the cords of the brachial plexus names for?
their positions in relation to the axillary artery
52
What nerves of the brachial plexus are associated with anterior compartment innervation?
musculocutaneous n., median n., ulnar n.
53
What nerves of the brachial plexus are associated with posterior compartment innervation?
axillary n., radial n.
54
What is the important innervation of the dorsal scapular n.?
rhomboid mm.
55
What is the important innervation of the nerve to subclavius?
subclavius m.
56
What is the important innervation of the suprascapular nerve?
supraspinatus m. and infraspinatus m.
57
What is the important innervation of the long thoracic nerve?
serratus anterior muscle
58
What is the important innervation of the thoracodorsal nerve?
latissimus dorsi muscle
59
What is the important innervation of the lateral pectoral nerve?
pectoralis major muscle
60
What is the important innervation of the medial pectoral nerve?
pectoralis major m. and pectoralis minor m.
61
What is the important innervation of the musculocutaneous nerve?
anterior compartment arm muscles
62
What is the important innervation of the median nerve?
some anterior forearm muscles, some hand muscles
63
What is the important innervation of the ulnar nerve?
some forearm muscles, some hand muscles
64
What is the important innervation of the axillary nerve?
teres minor muscle and deltoid muscle
65
What is the important innervation of the radial nerve?
all posterior arm/forearm muscles
66
What are the 4 muscles included in the upper arm muscles?
-biceps brachii
-brachialis
-coracobrachialis
-triceps brachii
67
What are the muscles in the anterior compartment of the upper arm?
biceps brachii
brachialis
coracobrachialis
68
What are the muscles in the posterior compartment of the upper arm?
triceps brachii (3 heads)
69
What is the innervation of the anterior compartment of the upper arm?
musculocutaneous n.
70
What is the innervation of the posterior compartment of the upper arm?
radial n.
71
What is the origin of the biceps brachii and the coracobrachialis?
scapula
72
What is the origin of the brachialis?
humerus
73
What is the insertion of the biceps brachii?
radius
74
What is the insertion of the brachialis?
ulna
75
What is the insertion of the coracobrachialis?
humerus
76
What is the innervation of the biceps brachii, brachialis, and coracobrachialis?
musculocutaneous n.
77
What is the action of the biceps brachii?
supinates forearm and flexes elbow
78
What is the action of the brachialis?
flexes elbow
79
What is the action of the coracobrachialis?
helps flex and adduct shoulder joint
80
What is the origin of the triceps brachii?
long: scapula
lateral: humerus
medial: humerus
81
What is the insertion of the triceps brachii?
ulna
82
What is the innervation of the triceps brachii?
radial n.
83
What is the action of the triceps brachii?
chief elbow extensor
84
What muscle resists shoulder dislocation?
coracobrachialis
85
What muscle is the most powerful forearm supinator?
biceps brachii
86
What muscle is the chief forearm flexor?
brachialis
87
What is the coracobrachialis pierced by?
musculocutaneous n.
88
What specific landmark does the biceps brachii insert onto?
radial tuberosity
89
What does the biceps brachii long head attach to?
intertubercular groove and transverse humerus ligament
90
What does the biceps brachii short head and coracobrachialis both attach to?
coracoid process where they both stabilize the glenohumeral joint
91
What specific landmark does the brachialis muscle attach to?
ulnar tuberosity
92
What is the specific landmark that the triceps brachii attach to?
proximal end of olecranon of ulna and fascia of forearm
93
What muscle is in the posterior compartment of the arm besides the triceps brachii?
anconeus
94
What is the origin of the anconeus?
lateral epicondyle of humerus
95
What is the insertion of the anconeus?
lateral surface of olecranon and superior part of the posterior surface of the ulna
96
What is the innervation of the anconeus?
radial n.
97
What are the actions of the anconeus?
assists triceps in extending elbow joint; stabilizes elbow joint; abducts ulna during pronation
98
What is the space located in the posterior shoulder region?
quadrangular space
99
what is the anterior border of the quadrangular space?
subscapularis m.
100
What is the superior border of the quadrangular space?
teres minor and capsule of shoulder joint
101
what is the inferior border of the quadrangular space?
teres major
102
What is the medial border of the quadrangular space?
long head of the triceps brachii
103
What is the lateral border of the quadrangular space?
surgical neck of the humerus
104
Posteriorly, the quadrangular space is bounded above by?
teres minor
105
What are the contents of the quadrangular space?
axillar n. and posterior circumflex humeral a. and v.
106
What is the quadrangular space created by?
humerus, long head triceps, teres major, teres minor
107
If the axillary n. if injured, what muscles are affected?
deltoid and teres minor
108
If the axillary n. is damages and affect the deltoid and teres minor muscle, what movements will be affected?
internal rotation and abduction (deltoid)
external rotation (teres minor)
109
What has a possibility of being damaged in a surgical neck fracture of the humerus?
-axillary n. and posterior circumflex a.
110
If the axillary n. gets severed by a fragment in a surgical neck fracture of the humerus, you will lose movement from what?
deltoid and teres minor
111
What movements will be affected with long thoracic n. injury?
scapular protraction
scapular rotation
holds scapula against thoracic wall
112
What can a long thoracic n. injury cause?
winged scapula
113
What muscle would be affected by a long thoracic n. injury?
serratus anterior m.
114
What nerve(s) can be damaged in mastectomy surgeries?
long thoracic nerve
thoracodorsal nerve
115
What occurs in Saturday night palsy?
compression of the radial nerve in the axilla
116
What can cause compression of the radial nerve in the axilla?
falling asleep improperly after a night drinking
using crutches improperly
117
When the radial nerve in the axilla is compressed for too long, what can occur?
complete paralyzation of elbow extension and wrest extension
118
What runs through the radial groove?
radial n. and deep brachial a.
119
In a humeral shaft fracture, what structures can be severed?
radial n. and deep brachial a.
120
What muscles would be affected in a humeral shaft fracture?
muscles innervated by the radial n.:
-triceps brachii
-anconeus
-posterior compartment of arm
