MSK Anatomy Flashcards
1
Q
rectus fibers run…
A
straight
2
Q
transversus fibers run…
A
at right angles
3
Q
oblique fibers run…
A
at angles to imaginary defined axis
4
Q
what are the muscles of mastication
A
four pairs, all innervated by cranial nerve 10
- jaw closure: temporalis and masseter
- grinding: pterygoids
- chewing: buccinator
5
Q
muscles promoting tongue movements
A
three extrinsic muscles anchor and move the tongue (all innervated by CN VII/hypoglossal)
- genioglossus
- hyoglossus
- styloglossus
6
Q
what muscle divides the neck into two triangles (ant and post)
A
SCM
7
Q
what are the anterior neck muscles
A
suprahyoid muscles
infrahyoid muscles
8
Q
process of swallowing
A
tongue and buccinator muscles push food back toward pharynx, where muscles in post mouth and pharynx complete swallowing
epiglottis closes over larynx while muscles in walls of pharynx propel food foward to stomach
9
Q
suprahyoid muscle group actions
A
four muscles involved in swallowing
- form floor of oral cavity
- anchor tongue
- elevate hyoid bone
- move larynx during swallowing
10
Q
infrahyoid muscle group actions
A
four straplike muscles that depress the hyroid bone and larynx during swallowing and speaking
- sternohyoid
- sternothyroid
- omohyroid
- thyrohyoid
11
Q
what muscles move the head
A
anterolateral neck muscles
12
Q
what muscles extend the trunk/maintain posture
A
intrinsic muscles of the back
13
Q
muscles of inspiration
A
diaphragm and external intercostals
- contraction = enlarges rib cage
- diaphragm divides thoracic and abdominal cavities
14
Q
muscles of expiration
A
expiration brought on by relaxation of inspiratory muscles (dec rib cage size), as well as contraction of internal intercostals
15
Q
action of anterior abdominal muscles
A
- lateral flexion and rotation of trunk
- compression of abdominal viscera
- promote urination, defacation, childbirth, vomiting, coughing, screaming
16
Q
anterior abdominal wall muscles
A
four paired muscles; their fasciae and aponeuroses form lateral and anterior abdominal wall
- rectus abdominis
- external obliques
- internal obliques
- transversus abdominis
all innervated by intercostal nerves
16
Q
muscles of pelvic diaphragm
A
two paired muscles, both innervated by sacral nerves
- levator ani
- coccygeus
17
Q
muscles of the urogenital diaphragm
A
- anterior half of perineum, inf to pelvic floor
- deep transverse perineal muscle
- contains external urethral sphincter (voluntary)
18
Q
muscles of superficial perineal space
A
- ischiocavernosus + bulbospongiosus help maintain erection of penis/clitoris
- superficial transverse perineal muscles
19
Q
where do C1-C7 nerve roots come out in relation to their vertebrae?
A
ABOVE the vertebrae
20
Q
where does C8 nerve root come out in relation to their vertebrae?
A
Above T1
21
Q
where do T1- coccygeal nerve roots come out in relation to their vertebrae?
A
BELOW the vertebrae
22
Q
where does the cervical cord nerve root come out in relation to their vertebrae?
A
1 above SP
23
Q
where does the thoracic cord nerve roots come out in relation to their vertebrae?
A
2 above SP
24
where does the lumbar cord nerve root come out in relation to their vertebrae?
4 above SP
25
rootlets location
extend out from dorsal and ventral horns and converge into ROOTS
26
dorsal and ventral horns location
exit vertebral column and unite to form SPINAL NERVE
27
spinal nerve splits into...
RAMI
28
remi innervation
- dorsal ramus innervates deep back muscles and overlying skin
- ventral remus innervates remaining muscles, skin, etc
29
____ form the brachial plexus
ventral/ant rami
30
most nerves we encounter are...
ventral rami
31
at what joint does the upper extremity articulate with the axial skeleton?
sternoclavicular
32
what are the muscles called that support, propel, and stabilize the pectoral girdle?
axioappendicular muscles
33
what nerves make up the brachial plexus? where do they innervate?
C5 - shoulder
C6 - elbow
C7 - wrist
C8 - hand
T1 - hand
34
brachial plexus trunks
C5 + C6 > 1st trunk
C7 > 2nd
C8 + T1 > 3rd
35
from which nerve roots on the brachial plexus does the long thoracic nerve run from?
C5-C7
36
from which nerve roots on the brachial plexus does the dorsal scapular nerve run from?
C5
37
what are the end branches of the brachial plexus? where do they stem from?
- musculocutaneous (C5-C7)
- axillary
- radial (C5-C8, T1)
- median (C5-C8, T1)
- ulnar (C8, T1)
38
where does the axillary nerve stem from?
off the radial nerve
39
what are the three trunks of the brachial plexus?
superior
middle
inferior
40
what is the order of splitting of the brachial plexus?
"Rugby Teams Don't Cover Bruises"
- 5 roots (C5-T1)
- 3 trunks (sup, mid, inf)
- 2 divisions (each trunk > ant + post)
- 3 cords (lateral, medial, post)
- 5 branches (musculocut, axil, median, radial, ulnar)
41
branches of the lateral cord of the brachial plexus
Rugby players are:
Long Legged Movers
- lat pectoral n
- lat root of medial n
- musculocutaneous n
42
branches of the medial cord of the brachial plexus
Rugby Players:
Make Many Moves Using Muscles
- medial brachial cutaneous n
- medial antebrachial cutaneous n
- medial pectoral n
- ulnar n
- medial root of median n
43
branches of the posterior cord of the brachial plexus
Rugby players are:
ULTRA competitive
- upper subscapular n
- lower subscapular n
- thoracodorsal n
- radial n
- axillary n
44
what four joints make up the shoulder
- glenohumoral
- sternoclavicular
- acromioclavicular
- scapulothoracic
45
what is the glenohumoral joint?
ball and socket joint between the head of humerus and the glenoid fossa of the scapula
capsule is thin and loose; lies in folds when arm is adducted, and is taunt when arm is abducted
46
what part of the glenohumeral capsule is weakest? why?
inf part is weakest bc its not reinforced by rotato cuff mm
47
what runs through an aperature in the glenohumeral capsule?
long head of biceps
48
what are the capsular ligaments of the glenohumeral joint? what are their functions?
- **glenohumeral**: thickening of ant capsule
- **coracohumeral**: strengthens sup part of capsule
- **transverse humeral**: holds down tendon
- **coracoacromial**: limits superior movement
49
what strengthens the shoulder/AC joint superiorly?
acromioclavicular ligament
50
where does most of the strenght of the acromioclavicular joint come from?
coracoclavicular ligament
- trapezoid ligament (extends to trapezoid line on inf clavicle)
- conoid ligament (attached to root of coracoid process and conoid tubercle on inf clavicle)
51
arterial supply of acromioclavicular joint
suprascapular and thoracoacromial arteries
52
nerve supply of acromioclavicular joint
supraclavicular, lateral pectoral, axillary
53
main superficial vessels of upper limb
cephalic and basilic
- originate in subcutaneous tissue on dorsum of hand from dorsal venous network
- both lead to axillary v
B > A
C > MC > A
54
basilic vein path
basilic vein ascends on medial side, pierces brachial fascia, runs superiorly and parallel to brachial atery and drains into axillary v
55
cephalic vein path
- ascents to ant elbow to communivate with median cubital vein
- cephalic passes b/w deltoid and pec major muscles in deltopectoral groove and enters delto/clavipectoral triange and pierces the costocoracoid membrane to join the axillary v
56
what is the main vein used in blood draws
median cubital vein
57
pec major origin
- medial clavicle
- sternum
- upper 6 costal cartilages (2 heads, clavicular and sternocostal)
58
pec major insertion
bicipital groove (humerus)
59
pec major nerve
medial and lateral pectoral nerves
60
pec major action
flex, adduct, medially rotate humerus
61
what forms the anterior axillary fold?
inferior border of pec major
62
pec minor origin
ribs 3,4,5
63
pec minor insertion
coracoid process of scapula (forms a bridge under which the neurovascular bundle travels)
63
pec minor nerve
medial pectoral n
64
pec minor action
- protraction, depression, med rotation of scapula
- stabilizes scapula, esp when stretching for something just out of reach
65
subclavius origin
1st costal cartilage
66
subclavius insertion
inf groove of clavicle
67
subclavius nerve
n to subclavius
68
subclavius action
- depresses and stabilizes scapula
- protects neurovascular bundle if clavicle breaks
69
serratus anterior action
- holds scapula to chest wall
- protraction and sup rotation of scapula
70
serratus anterior origin
external surfaces of ribs 1-8
70
serratus anterior insertion
medial border of scapula
71
trap origin
- sup nuchal line
- EOP
- nuchal ligament
- spines of C7-T12
72
trap insertion
- spine of scapula
- acromion
- lateral third of clavicle
73
serratus anterior innervation
long thoracic nerve
74
what forms the medial wall of the axilla?
serratus anterior
75
trap innervation
CN XI (accessory)
76
what is the posterior triangle
- space between trap, clavicle, and SCM
- brachial plexus and axillary artery pass between ant and middle scalene muscles
77
accessory nerve location
descends from base of skull, out of post triangle of neck, down side of neck, and deep to trapezeius
78
lat dorsi origin
- spines of T6-L5
- median crest of sacrum
- iliac crest
79
lat dorsi insertion
intertubercular groove of humerus
80
lat dorsi actions
extend, adduct, medially rotate humerus
- chin ups
81
lat dorsi innervation
thoracodorsal nerve
82
rhomboid minor origin and insertion
- O: SPs of C7-T1
- I: medial border of scapula, at level of spine
83
rhomboid major origin and insertion
- O: SPs of T2-T5
- I: medial border of scapula, below level of spine
84
levator scapulae origin, insertion, and relationship to SCM
- deep to SCM
- O: TPs of C1-4
- I: medial border of scapula, above the spine
85
levator scap, rhomboid major, rhomboid minor actions
- ALL elevate, retract, and medially rotate the scapula
- LEV SCAP ONLY - unilaterally flexes neck, B/L extends neck
86
levator scap, rhomboid major, rhomboid minor innervation
dorsal scapular nerve
87
nerves to muscles of the superficial back and what CN they come off of
- dorsal scapular (CN5)
- suprascapular (CN5,6)
- accessory (CN XI)
- axillary (CN
88
muscles on the scapula that move the humerus
- deltoid
- supraspinatus
- infraspinatus
- subscapularis
- teres major
- teres minor
- triceps
89
deltoid origin
CLASPs
- clavicle (lateral 1/3, ant deltoid)
- acromion (intermediate deltoid)
- SPine of scapula (post deltoid)
90
deltoid insertion
deltoid tuberosity of humerus
91
deltoid innervation
axillary
92
deltoid actions
acts on humerus
- flex and extend
- abduct (all 3 parts together)
- medially and laterally rotate
93
axillary nerve innervation, location, clinical importance
- innervates deltoid and teres minor
- passes through quadrangular space b/w teres and the long head of triceps and humerus
Clinical: quadrilateral space syndrome (QSS) = compression of axillary n and post humeral circumflex artery as they pass through this space
94
what are the rotator cuff muscles?
SITS (clockwise from top)
- supraspinatus
- infraspinatus
- teres minor
- subscapularis
tendons of all these blend w glenohumeral joint capsule, reinforcing it
95
supraspinatus origin and insertion
O: supraspinous fossa
I: greater tubercle
96
supraspinatus action
abduct humerus (with deltoid)
97
supraspinatus innervation
suprascapular n
98
infraspinatous origin and insertion
O: infraspinous fossa
I: greater tubercle
99
infraspinatous action
laterally rotates humerus
100
infraspinatous innervation
suprascapular n
101
teres minor origin and insertion
O: lat border scap
I: greater tubercle humerus
101
teres minor action
laterally rotates humerus
102
teres minor innervation
axillary nerve
103
subscapularis origin and insertion
O: subscapular fossa
I: lesser tubercle
104
subscapularis action
medially rotates humerus
105
subscapularis innervation
upper and lower subscapular nerves
106
suprascapular nerve pathway, innervation
- originates from upper trunk of brachial plexus
- passes thru suprascapular foramen > post scapular region
- innervates supraspinatus
- passes thru greater scap (spinoglenoid) notch
- terminates in and innervates infraspinatus
107
teres major origin and insertion
O: lateral border scap
I: medial intertubercular groove
108
teres major action
adduct, medially rotate, and extend humerus
109
teres major innervation
lower subscapular nerve (off axillary nerve)
110
arteries of upper limb
- subclavian: bw ant and middle scalenes
- axillary: from lat 1st rib > lower teres major
- brachial: from teres major > bifurcation of R + U arteries
- radial
- ulnar
- deep and superficial palmar arches
- digital arteries
111
location of axillary artery
lateral border of first rib > inf border teres major
112
axillary artery divisions
divided into three parts relative to pec minor
- 1st: gives rise to sup thoracic artery and is enclosed in the axillary sheath
- 2nd: post to pec minor and gives rise to thoracoacromial and lateral thoracic arteries which pass medial and lateral to the muscle respectively
- 3rd: supscapular (largest branch), and anterior + posterior circumflex humeral arteries
113
collateral circualtion around scapula
anastomoses from subclavian and axillary arteries
- dorsal scapular a (vertebral scap border)
- suprascap a (supra and infraspinous fossa)
- circumflex scapular a (medial triangular space)
- transverse cervical artery
114
elbow joint ligaments, arterial supply, and innvervation
- ulnar collateral
- radial collateral
- annular
arterial: anastomasis of arteries around elbow joint
innervation: musculocutaneous, radial, ulnar nerves
115
ulnar collateral anatomy
triangular shaped, upper and lower bands (ulnar nerve passes bw bands post to medial epicondyle)
"funny bone"
116
radial collateral ligament anatomy
attached to annular ligament
117
annular ligament anatomy
sling around head of radius to form proximal radioulnar joint
118
proximal radioulnar joint
joint type, ligaments
pivot type synovial joint
- annular ligament (permits rotation of head of radius around ulna)
- interosseous membrane (links bones together)
119
muscles of the arms, innervation rules to live by
- all extensors and supinators: radial n
- all "pronator" names: median nerve
- flexors: musculocutaneous
this means some have 2
120
MAIN arm flexor
brachialis; the only PURE flexor, produces the most force
121
brachialis origin and insertion
O: ant surface of distal half of humerus
I: coronoid process/ulnar tuberosity of ulna
122
brachialis innervation
musculocutanous
(in some people it also includes radial)
123
brachialis action
flexes forearm in slow and quick movements
steadies arm during extension by slow relaxation
124
coracobrachialis origin and insertion
O: coracoid process
I: middle 1/3 humerus
125
coracobrachialis action
flex and adduct arm
stabilizes glenohumeral joint
126
coracobrachialis innervation
musculocutaneous (pierced by the nerve which then continued as lateral cutaneous nerve of forearm)
127
triceps origin and insertion
O
- long head: infraglenoid tubercle
- lateral head: post humerus (sup/lat to radial groove)
- medial head: post humerus (inf/med to radial groove)
I: olecranon process of ulna
128
triceps innervation
radial n
129
triceps action
extends arm and forearm
stabilizes adducted glenohumeral joint
130
what muscle helps the tricep extend the forearm and also abducts humerus during forearm pronation?
anconeus m
131
what nerves would be affected by fractures at different points of the humerus?
ARM
- Axillary: head of humerus
- Radial: mid shaft
- Median: supracondylar
132
cubital fossa boundaries
- medial: pronator teres
- lateral: brachioradialis
- superior: imaginary line connecting medial and lateral epicondyles of humerus
- floor: brachialis + supinator mm
- roof: brachial and antebrachial fascia w/ bicipital aponeurosis
133
structures in the cubital fossa
Really Need Beer To Be At My Nicest (lateral to medial)
- radial n
- biceps tendon
- brachial artery
- median nerve
134
flexor digitorum superficialis anatomy, insertion, innervation, action
intermediate layer
inserts on middle phalanges of 4 fingers
median n
flexes fingers
135
deep layer of lower arm muscles
- flexor digitorum profundus
- flexor pollicus longus
- pronator quadratus
136
flexor digitorum profundus insertion and innervation
inserts on distal phalanges
median n to radial half
ulnar n to ulnar half
137
flexor pollicis longus insertion and innervation
inserts on distal phalanx of thumb
median n
138
pronator quadratus location and innervation
extends from ulna to radius
prime mover for pronation, reinforces interosseus membrane (keeps radius and ulna together, esp in FOSH injury)
median n
139
extensor muscles of the forearm (post)
- mm that extend/abduct/adduct hand at the wrist (extensor carpi radialis longus, extensor carpi radialis brevis, extensor carpi ulnaris)
- extend the medial four digits (extensor digitorum, extensor indicis, extensor digiti minimi)
- extend/abduct thumb (abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus)
140
brachioradialis origin, insertion, innervation, and action
origin on lat humerus
inserts on radius
radial n
flexes elbow, maintains half pronated position "beer drinking muscle"
141
extensors carpi radialis longus and brevis
insertion, innervation, action
insert on MC 2,3
radial n
extends and radially deviates wrist
142
extensors digitorum and digiti minimi
insertion, innervation, action
insert into extensor expansions over middle and distal phalanges
radial n
extends fingers
143
extensor carpi ulnaris
insertion, innervation, action
insert on MC 5
radial n
extends wrist and ulnar deviate
144
posterior forearm muscles and innervation
- supinator
- abductor pollicis longus
- extensor pollicis brevis
- extensor pollicis longus
- extensor indicis
radial n
145
ulnar nerve location and innervation
- passes post to medial epicondyle > enters forearm between heads of flexor carpi ulnaris > down ulnar side between this and FCU and FDP > becomes superficial at wrist
innervates
- flexor carpi ulnaris
- 1/2 of flexor digitorum profundus
146
what artery is used to take BP
brachial
147
superficial palmar arch anatomy
- formed primarily by ulnar artery, as it enters palm through tunnel of guyon
- anastomosis with radial artery
148
structures in carpal tunnel
- median n
- flexors digitorum superficialis and profundus
- flexor pollicis longus
149
carpal tunnel syndrome results
- cutaneous senosry loss on median n distribution (thumb, pointer, middle)
- thenar wasting
- weakness of lumbricals 1,2
150
ulnar n innervation cutaneous
1.5 digits, ulnar side of palm, dorsum of hand
