Muscle Attachment Flashcards
(121 cards)
1
Q
Obturator Internus
A
Pelvic surface of ilium and ischium; obturator membrane –> medial surface of greater trochanter
Innervation: nerve to obturator internus
Action: laterally rotates extended hip joint; abducts flexed hip joint; steadies femoral head in acetabulum (stabilizes hip joint)
2
Q
Piriformis
A
Pelvic surface of sacral segments 2-4; superior margin of greater sciatic notch and sacrotuberous ligament –> greater trochanter
Innervation: branches of anterior rami of S1, S2
Action: laterally rotates extended hip joint; abducts flexed hip joint; steadies femoral head in acetabulum (stabilizes hip joint)
3
Q
Psoas major
A
Transverse processes of lumbar vertebrae; vertebral bodies of T12-S1 vertebrae and intervening IV discs –> by a strong tendon to lesser trochanter
Innervation: anterior rami of lumbar nerves
Action: a postural muscle that helps control deviation of the trunk and is active during standing; acting with iliacus in flexing hip joint and in stabilizing this joint
4
Q
Iliacus
A
Superior 2/3 of iliac fossa, ala of sacrum, anterior sacroiliac ligaments –> psoas major tendon, lesser trochanter and shaft inferior to it
Innervation: femoral nerve
Action: acting with psoas major in flexing hip joint and in stabilizing this joint
5
Q
Quadratus lumborum
A
Medial half of inferior border of 12th rib and tips of lumbar transverse processes –> iliolumbar ligament and internal lip of iliac crest
Innervation: twelfth thoracic and first through fourth ventral rami of lumbar nerves (T12, L1-L4)
Action: alone (unilateral), lateral flexion of vertebral column; together (bilateral), depression of thoracic rib cage
6
Q
Pectineus
A
Superior ramus of pubis –> pectineal line of femur just inferior to lesser trochanter
Innervation: femoral nerve
Action: adducts and flexes hip joint; assists with medial rotation of hip joint
7
Q
Sartorius
A
ASIS and superior part of notch inferior to it –> superior part of medial surface of tibia
Innervation: femoral nerve
Action: flexes, abducts and laterally rotates hip joint; flexes knee joint
8
Q
Rectus femoris
A
AIIS and ilium superior to acetabulum –> via common tendinous (quadriceps tendon) and independent attachments to base of patella; indirectly via patellar ligament to tibial tuberosity
Innervation: femoral nerve
Action: extend knee joint; stabilizes (helps fix in position) hip joint and helps iliopsoas flex hip joint
9
Q
Vastus lateralis
A
Greater trochanter and lateral lip of linea aspera –> patella and tibial tuberosity, and tibia and patella via aponeurosis (lateral patellar retinaculum)
Innervation: femoral nerve
Action: extends knee joint
10
Q
Vastus medialis
A
Intertrochanteric line and medial lip of linea aspera –> patella and tibial tuberosity, and tibia and patella via aponeurosis (medial patellar retinaculum)
Innervation: femoral nerve
Action: extends knee joint
11
Q
Vastus intermedius
A
Anterior and lateral surfaces of shaft of femur –> patella and tibial tuberosity
Innervation: femoral nerve
Action: extends knee joint
12
Q
Adductor longus
A
Body of pubis inferior to pubic crest –> middle third of linea aspera
Innervation: obturator nerve
Action: adducts hip joint
13
Q
Adductor brevis
A
Body and inferior ramus of pubis –> pectineal line and proximal part of linea aspera
Innervation: obturator nerve
Action: adducts hip joint and to some extent flexes it
14
Q
Adductor magnus
A
Inferior ramus of pubis, ramus of ischium (adductor part); ischial tuberosity (hamstring part) –> gluteal tuberosity, linea aspera, medial supracondylar line (adductor part); adductor tubercle (hamstring part)
Innervation: obturator nerve (adductor part), tibial part of sciatic nerve (hamstring part)
Action: adducts hip joint; its adductor part also flexes hip joint and its hamstring part extends it
15
Q
Gracilis
A
Body and inferior ramus of pubis –> superior part of medial surface of tibia
Innervation: obturator nerve
Action: adducts hip joint; flexes knee joint and helps rotate it medially
16
Q
Obturator externus
A
Margins of obturator foramen and obturator membrane –> trochanteric fossa of femur
Innervation: obturator nerve
Action: laterally rotates hip joint; pulls head of femur into acetabulum holding pelvis steady
17
Q
Gluteus maximus
A
Ilium posterior to posterior gluteal line; dorsal surface of sacrum and coccyx; and sacrotuberous ligament –> most fibers end in iliotibial tract, which inserts into lateral condyle of tibia; some fibers insert on gluteal tuberosity of femur
Innervation: inferior gluteal nerve
Action: extends hip joint between flexed and standing positions and assists in its lateral rotation; steadies thigh and assists in rising from sitting position
18
Q
Gluteus medius
A
External surface of ilium between anterior and posterior gluteal lines –> lateral surface of greater trochanter
Innervation: superior gluteal nerve
Action: abducts and anterior portions medially rotate hip joint, keep pelvis level when opposite limb is elevated; posterior laterally rotates
19
Q
Gluteus minimus
A
External surface of ilium between anterior and inferior gluteal lines –> anterior surface of greater trochanter
Innervation: superior gluteal nerve
Action: abduct and anterior portions medially rotate hip joint and posterior portions laterally rotate the hip joint; keep pelvis level when opposite limb is elevated
20
Q
Tensor fascia latae
A
ASIS; anterior part of iliac crest –> iliotibial tract, which attaches to lateral condyle of tibia (gerdy tubercle)
Innervation: superior gluteal nerve
Action: flexes hip joint; acts with gluteus maximus to stabilize the extended knee joint
21
Q
Superior and inferior gemellus
A
Ischial tuberosity (inferior); ischial spine (superior) –> medial surface of greater trochanter (trochanteric fossa)
Innervation: nerve to obturator internus (superior), nerve to quadratus femoris (inferior)
Action: laterally rotates extended hip joint; abducts flexed hip joint; steadies femoral head in acetabulum (stabilizes hip joint)
22
Q
Quadratus femoris
A
Lateral border of ischial tuberosity –> quadrate tubercle on intertrochanteric crest of femur and area inferior to it
Innervation: nerve to quadratus femoris
Action: laterally rotates hip joint; also pulls femoral head into acetabulum to stabilize hip joint/pelvis
23
Q
Semitendinosus
A
Ischial tuberosity –> medial surface of superior part of tibia
Innervation: tibial division of sciatic nerve
Action: extend hip joint; flex knee joint and rotate the leg medially when knee is flexed; when hip and knee are flexed, can extend trunk
24
Q
Semimembranosus
A
Ischial tuberosity –> posterior part of medial condyle of tibia; reflected attachment forms oblique popliteal ligament (to lateral femoral condyle)
Innervation: tibial division of sciatic nerve
Action: extend hip joint; flex knee joint and rotate the leg medially when knee is flexed; when hip and knee are flexed, can extend trunk
25
Biceps femoris
Ischial tuberosity (long head); linea aspera and lateral supracondylar line of femur --> lateral side of head of fibula; tendon is split at this site by fibular collateral ligament
Innervation: tibial division of sciatic nerve (long head), common fibular division of sciatic nerve (short head)
Action: flexes knee joint and rotates it laterally when knee is flexed; extends hip joint
26
Tibialis anterior
Lateral condyle and superior 2/3 of lateral surface of tibia and interosseous membrane --> medial and inferior surfaces of medial cuneiform and base of 1st metatarsal
Innervation: deep fibular nerve
Action: dorsiflexes ankle; inverts foot; supports medial longitudinal arch of foot
27
Extensor hallucis longus
Middle part of anterior surface of fibula and interosseous membrane --> dorsal aspect of base of distal phalanx of hallux (big toe)
Innervation: deep fibular nerve
Action: extends great toe; dorsiflexes ankle
28
Extensor digitorum longus
Lateral condyle of tibia and superior 2/3 of anterior surface of fibula and interosseous membrane --> middle and distal phalanges of lateral 4 digits
Innervation: deep fibular nerve
Action: extends lateral four digits; dorsiflexes ankle
29
Fibularis tertius
Inferior third of anterior surface of fibula and interosseous membrane --> dorsum of base of 5th metatarsal
Innervation: deep fibular nerve
Action: dorsiflexes ankle; aids in eversion of foot
30
Fibularis longus
Head and superior 2/3 of lateral surface of fibula --> base of 1st metatarsal and medial cuneiform
Innervation: superficial fibular nerve
Action: evert foot; weakly plantarflexes ankle; supports transverse arch of foot
31
Fibularis brevis
Middle part of lateral surface of fibula --> dorsal surface of tuberosity of base of 5th metatarsal
Innervation: superficial fibular nerve
Action: plantarflexes and everts foot
32
Gastrocnemius
Lateral aspect of lateral condyle of femur (lateral head); popliteal surface of femur, superior to medial condyle --> posterior surface of calcaneus via calcaneal tendon
Innervation: tibial nerve
Action: plantarflexes ankle when knee is extended; raises heel during walking; and flexes knee joint
33
Soleus
Posterior aspect of head of fibula, superior quarter of posterior surface of fibula, soleal line, and medial border of tibia --> posterior surface of calcaneus via calcaneal tendon
Innervation: tibial nerve
Action: plantarflexes ankle; steadies leg on foot
34
Plantaris
Inferior end of lateral supracondylar line of femur and oblique popliteal ligament --> posterior surface of calcaneus via calcaneal tendon
Innervation: tibial nerve
Action: weakly assists gastrocnemius in plantarflexing ankle; function is probably mainly proprioceptive
35
Popliteus
Lateral surface of lateral condyle of femur and lateral meniscus (intra-articular; within cavity of knee joint) --> posterior surface of tibia, superior to soleal line
Innervation: tibial nerve
Action: weakly flexes knee and unlocks it by laterally rotating femur on fixed tibia, may also medially rotate tibia of unplanted limb
36
Flexor hallucis longus
Inferior 2/3 of posterior surface of fibula and inferior part of interosseous membrane --> base of distal phalanx of hallux
Innervation: tibial nerve
Action: flexes great toe at all joints; weakly plantarflexes ankle; supports medial longitudinal arch of foot
37
Flexor digitorum longus
Medial part of posterior surface of tibia, inferior to soleal line and by a broad tendon to fibula --> distal phalanges
Innervation: tibial nerve
Action: flexes lateral four digits; plantarflexes ankle; supports longitudinal arches of the foot
38
Tibialis posterior
Interosseous membrane, posterior surface of tibia inferior to soleal line, and posterior surface of fibula --> primarily to tuberosity of navicular; also cuneiforms, cuboid and bases of 2nd-4th metatarsals
Innervation: tibial nerve
Action: plantarflexes ankle; inverts foot; supports medial longitudinal arch of foot
39
Abductor hallucis
Medial tubercle of tuberosity of calcaneus, flexor retinaculum, and plantar aponeurosis --> medial side of base of proximal phalanx of 1st digit
Innervation: medial plantar nerve
Action: abducts and flexes 1st digit (great toe, hallux) (at MCP joint)
40
Flexor digitorum brevis
Medial tubercle of tuberosity of calcaneus, plantar aponeurosis, and intermuscular septa --> both sides of middle phalanges of lateral four digits
Innervation: medial plantar nerve
Action: flexes lateral four digits at PIP and MTP joints
41
Abductor digiti minimi
Medial and lateral tubercles of tuberosity of calcaneus, plantar aponeurosis, and intermuscular septa --> lateral side of base of proximal phalanx of 5th digit
Innervation: lateral plantar nerve
Action: abducts and flexes 5th digit at MTP joint
42
Quadratus plantae
Medial surface and lateral margin of plantar surface of calcaneus --> posterolateral margin of tendon of flexor digitorum longus
Innervation: lateral plantar nerve
Action: assists flexor digitorum longus in flexing lateral four digits
43
Lumbricals (foot)
Tendons of flexor digitorum longus --> medial aspect of expansion over lateral four digits
Innervation: medial plantar nerve (medial one), lateral plantar nerve (lateral three)
Action: flex proximal phalanges; extend middle and distal phalanges of lateral four digits
44
Flexor hallucis brevis
Plantar surfaces of cuboid and lateral cuneiform --> both sides of base of proximal phalanx of 1st digit
Innervation: medial plantar nerve
Action: flexes proximal phalanx of 1st digit
45
Adductor hallucis
Bases of metatarsals 2-4 (oblique head); plantar ligaments of 3rd-5th metatarsophalangeal joints (transverse head) --> tendons of both heads attach to lateral side of base of proximal phalanx of 1st digit
Innervation: deep branch of lateral plantar nerve
Action: adducts 1st digit; assists in maintaining transverse arch of foot
46
Flexor digiti minimi brevis (foot)
Base of 5th metatarsal --> base of proximal phalanx of 5th digit
Innervation: superficial branch of lateral plantar nerve
Action: flexes proximal phalanx of 5th digit, thereby assisting with its flexion
47
Plantar interossei (three muscles)
Bases and medial sides of metatarsals 3-5 --> medial sides of bases of proximal phalanges of 3rd-5th digits
Innervation: lateral plantar nerve
Action: adduct digits (3-5) and flex MTP joints
48
Dorsal interossei (foot; four muscles)
Adjacent sides of metatarsals 1-5 --> medial side of proximal phalanx of 2nd digit (first); lateral sides of 2nd-4th digits (second to fourth)
Innervation: lateral plantar nerve
Action: abduct digits (2-4) and flex MTP joints
49
External/internal/innermost intercostals
Inferior border of ribs --> superior border of ribs below
Innervation: intercostal nerve
Action: elevate ribs during forced inspiration (external); during forced inspiration: interosseous part depresses ribs and interchondral part elevates ribs (internal and innermost)
50
Transversus thoracis
Posterior surface of lower sternum --> internal surface of costal cartilages 2-6
Innervation: intercostal nerve
Action: weakly depresses ribs
51
Subcostal
Internal surface of lower ribs near their angles --> superior borders of 2nd or 3rd ribs below
Innervation: intercostal nerve
Action: during forced inspiration: interosseous part depresses ribs and interchondral part elevates ribs (same as internal)
52
Levatores costarum
Transverse processes of C7-T11 --> subadjacent ribs between tubercle and angle
Innervation: posterior rami of C8-T11 nerves
Action: elevate ribs
53
Serratus posterior superior
Nuchal ligament, spinous processes of C7-T3 vertebrae --> superior borders of 2nd-4th ribs
Innervation: 2nd-5th intercostal nerves
Action: elevate ribs
54
Serratus posterior inferior
Inferior borders of 8th-12th ribs near their angles --> spinous processes of T11-L2 vertebrae
Innervation: 9th-11th intercostal nerves, subcostal (T12) nerve
Action: depress ribs
55
External obliques
External surface of ribs 5-12 --> linea alba, pubic tubercle, and anterior half of iliac crest
Innervation: thoraco-abdominal nerves (anterior rami of T7-T11) and subcostal nerve
Action: compress and support abdominal viscera; flex and rotate trunk
56
Internal obliques
Thoracolumbar fascia, anterior 2/3 of iliac crest, and connective tissue deep to inguinal ligament --> inferior borders of 10th-12th ribs, linea alba, and pubis via conjoint tendon
Innervation: thoraco-abdominal nerves (anterior rami of T7-T11), subcostal nerve and first lumbar nerve
Action: compress and support abdominal viscera; flex and rotate trunk
57
Transversus abdominus
Internal surfaces of 7th-12th costal cartilages, thoracolumbar fascia, iliac crest, and connective tissue deep to inguinal ligament --> linea alba with aponeurosis of internal oblique, pubic crest, and pubis via conjoint tendon
Innervation: thoraco-abdominal nerves (anterior rami of T7-T11), subcostal nerve and first lumbar nerve
Action: compresses and supports abdominal viscera
58
Rectus abdominus
Pubic symphisis and pubic crest --> xiphoid process and 5th-7th costal cartilages
Innervation: thoraco-abdominal and subcostal nerves (anterior rami of T7-T12 spinal nerves)
Action: flexes trunk (lumbar vertebrae) and compresses abdominal viscera, stabilizes and controls tilt of pelvis
59
Splenius capitis
Nuchal ligament, spinous processes of C7-T6 --> superolaterally to mastoid process of temporal bone and lateral 1/3 of superior nuchal line of occipital bone
Innervation: posterior rami of spinal nerves
Action: acting alone: laterally flex neck and rotate head to side of active muscles; acting together: extend head and neck
60
Splenius cervicis
Nuchal ligament, spinous processes of C7-T6 --> tubercles of transverse processes of C1-C3/C4
Innervation: posterior rami of spinal nerves
Action: acting alone: laterally flex neck and rotate head to side of active muscles; acting together: extend head and neck
61
Erector spinae
Broad tendon from posterior part of iliac crest, posterior surface of sacrum, sacro-iliac ligaments, sacral and inferior lumbar spinous processes, and supraspinous ligament --> fibers run superiorly to angles of lower ribs and cervical transverse processes (iliocostalis); fibers run superiorly to ribs between tubercles and angles to transverse processes in thoracic and cervical regions and to mastoid process of temporal bone (longissimus); fibers run superiorly to spinous processes in upper thoracic region and to cranium (spinalis)
Action: bilaterally: extend vertebral column and head, as back is flexed, control movement by gradually lengthening fibers; unilaterally: laterally flex vertebral column
62
Semispinalis
Transverse processes of C4-T10 --> fibers run superomedially to occipital bone and spinous processes in upper thoracic and cervical regions, spanning 4-6 segments
Innervation: posterior rami of spinal nerves
Action: extends head, thoracic, and cervical regions of vertebral column and rotates them contralaterally
63
Multifidus
Thickest in lumbar region, fibers pass superomedially to entire length of spinous processes of vertebrae 2-4 segments superior to origin
Innervation: posterior rami of spinal nerves
Action: unilateral contraction rotates to contralateral side; stabilizes vertebrae during local movements of vertebral column
64
Brachioradialis
Proximal 2/3 of lateral supracondylar ridge of humerus --> lateral surface of distal end of radius proximal to styloid process
Innervation: radial nerve
Action: relatively weak flexion of elbow, maximal with midpronated forearm
65
Extensor carpi radialis longus
Lateral supracondylar ridge of humerus --> dorsal aspect of base of 2nd metacarpal
Innervation: radial nerve
Action: extends and radially deviates wrist
66
Extensor carpi radialis brevis
Lateral epicondyle of humerus --> dorsal aspect of 3rd metacarpal
Innervation: deep branch of radial nerve
Action: extends and radially deviates wrist; also active during fist clenching
67
Extensor digitorum
Lateral epicondyle of humerus --> extensor expansions of middle four fingers
Innervation: posterior interosseous nerve from deep branch of radial nerve
Action: extend wrist; extend middle four MCP joints (primarily) and IP joints (secondarily)
68
Extensor digiti minimi
Lateral epicondyle of humerus --> extensor expansion of 5th finger
Innervation: posterior interosseous nerve from deep branch of radial nerve
Action: extends wrist and 5th finger at MCP joint (primarily) and IP joints (secondarily)
69
Extensor carpi ulnaris
Lateral epicondyle; posterior border of ulna via a shared aponeurosis --> dorsal aspect of base of 5th metacarpal
Innervation: posterior interosseous nerve from deep branch of radial nerve
Action: ulnar deviation and wrist extension (also active during fist clenching)
70
Supinator
Lateral epicondyle, radial collateral and anular ligaments, supinator fossa, and crest of ulna --> lateral, posterior, and anterior surfaces of proximal third of radius
Innervation: deep branch of radial nerve
Action: supinates forearm; rotates radius to turn palm anteriorly or superiorly (if elbow is flexed)
71
Abductor pollicis longus
Posterior surface of proximal halves of ulna, radius, and interosseous membrane --> base of 1st metacarpal
Innervation: posterior interosseous nerve; from deep branch of radial nerve
Action: extends wrist; abducts and extends thumb at CMC joint
72
Extensor pollicis longus
Posterior surface of middle third of ulna and interosseous membrane --> dorsal aspect of base of distal phalanx of thumb
Innervation: posterior interosseous nerve; from deep branch of radial nerve
Action: extends wrist; extends IP, MCP, and CMC joints
73
Extensor pollicis brevis
Posterior surface of distal third of radius and interosseous membrane --> dorsal aspect of base of proximal phalanx of thumb
Innervation: posterior interosseous nerve; from deep branch of radial nerve
Action: extends wrist; extends MCP and CMC joints
74
Extensor indicis
Posterior surface of distal third of ulna and interosseous membrane --> extensor expansion of 2nd finger
Innervation: posterior interosseous nerve; from deep branch of radial nerve
Action: extends wrist; extends 2nd finger (enabling its independent extension)
75
Pronator teres
Coronoid process of ulna (ulnar head); medial epicondyle (humeral head) --> middle convexity of lateral surface of radius
Innervation: median nerve
Action: pronates and flexes forearm
76
Flexor carpi radialis
Medial epicondyle of humerus --> base of 2nd (3rd) metacarpal
Innervation: median nerve
Action: flexes and radially deviates wrist
77
Palmaris longus
Medial epicondyle --> distal half of flexor retinaculum, palmar aponeurosis
Innervation: median nerve
Action: flexes wrist and tenses palmar aponeurosis
78
Flexor carpi ulnaris
Olecranon and posterior border of ulna (via aponeurosis) --> base of 5th metacarpal
Innervation: ulnar nerve
Action: wrist flexion and ulnar deviation
79
Flexor digitorum superficialis
Medial epicondyle and coronoid process of ulna (humeroulnar head); oblique line of radius (radial head) --> shafts (bodies) of middle phalanges of medial four digits
Innervation: median nerve
Action: wrist flexion; flexes middle four PIP joints and MCP joints
80
Flexor digitorum profundus
Proximal 3/4 of medial and anterior surfaces of ulna and interosseous membrane --> bases of distal phalanges of digits 2-5
Innervation: median nerve; anterior interosseous branch (lateral part), ulnar nerve (medial part)
Action: wrist flexion; flexes middle four DIP, PIP, and MCP joints
81
Flexor pollicis longus
Anterior surface of radius and adjacent interosseous membrane --> base of distal phalanx of thumb
Innervation: anterior interosseous nerve from median nerve
Action: wrist flexion; flexes IP and MCP joint of thumb
82
Pronator quadratus
Distal surface of anterior surface of ulna --> distal surface of anterior surface of radius
Innervation: anterior interosseous nerve from median nerve
Action: pronates forearm; deep fibers bind ulna and radius together
83
Biceps brachii
Tip of coracoid process of scapula (short head); supraglenoid tubercle of scapula (long head) --> tuberosity of radius and fascia of forearm via bicipital aponeurosis
Innervation: musculocutaneous
Action: supinates forearm and flexes elbow when supinated; flexes shoulder; short head resists dislocation
84
Brachialis
Distal half of anterior surface of humerus --> coronoid process and tuberosity of ulna
Innervation: musculocutaneous
Action: flexes elbow
85
Coracobrachialis
Tip of coracoid process of scapula --> middle third of medial humerus
Innervation: musculocutaneous
Action: helps flex and adduct the shoulder; resists dislocation
86
Triceps brachii
Infraglenoid tubercle of scapula (long head); posterior surface of humerus, superior to radial groove (lateral head); posterior surface of humerus, inferior to radial groove (medial head) --> proximal end of olecranon of ulna and fascia of forearm
Innervation: radial nerve
Action: chief extensor of elbow; long head extends shoulder joint and resists dislocation (especially important during abduction)
87
Anconeus
Lateral epicondyle of humerus --> lateral surface of olecranon and superior part of posterior surface of ulna
Innervation: radial nerve
Action: assists triceps in extending elbow joint; stabilizes elbow joint; abducts ulna during pronation
88
Deltoid
Lateral third of clavicle (anterior); acromion (middle); spine of scapula (posterior) --> deltoid tuberosity of humerus
Innervation: axillary nerve
Action: clavicular (anterior): flexes and medially rotates shoulder; acromial (middle): abducts shoulder; spinal (posterior): extends and laterally rotates shoulder
89
Supraspinatus
Supraspinous fossa of scapula --> superior facet of greater tubercle of humerus
Innervation: suprascapular nerve
Action: initiates and assists deltoid in abduction of shoulder joint and acts with other rotator cuff muscles
90
Infraspinatus
Infraspinous fossa of scapula --> middle facet of greater tubercle of humerus
Innervation: suprascapular nerve
Action: laterally rotates shoulder joint; help hold humeral head in glenoid cavity of scapula
91
Teres minor
Middle part of lateral border of scapula --> inferior facet of greater tubercle of humerus
Innervation: axillary nerve
Action: laterally rotates shoulder joint; help hold humeral head in glenoid cavity of scapula
92
Teres major
Inferior part of lateral border of scapula posterior surface of inferior angle of scapula --> medial lip of bicipital groove
Innervation: lower subscapular nerve
Action: adducts and medially shoulder
93
Subscapularis
Subscapular fossa (most of anterior surface of scapula) --> lesser tubercle of humerus
Innervation: upper and lower subscapular nerves
Action: medially rotates and adducts shoulder joint; helps hold humeral head in glenoid cavity
94
Trapezius
Medial third of superior nuchal line, external occipital protuberance, nuchal ligament, spinous processes of C7-T12 --> lateral third of clavicle (upper); acromion (middle); spine of scapula (lower)
Innervation: spinal accessory nerve (CNXI: motor fibers) and C3, C4 spinal nerves (pain and proprioceptive fibers)
Action: descending (superior): elevates scapula; ascending (inferior): depresses scapula; middle: retracts scapula; descending and ascending parts act together to rotate glenoid cavity superiorly
95
Latissimus dorsi
Spinous processes of inferior six thoracic vertebrae, thoracolumbar fascia, iliac crest, and inferior three or four ribs --> floor of bicipital groove
Innervation: thoracodorsal
Action: extends, adducts, and medially rotates shoulder joint; raises body toward arms during climbing
96
Levator scapulae
Posterior tubercle of transverse processes of C1-C4 vertebrae --> medial border of scapula, superior to root of spine
Innervation: dorsal scapular and cervical (C3, C4) spinal nerves
Action: elevates scapula and tilts its glenoid cavity inferiorly by rotating scapula
97
Rhomboid minor
Nuchal ligament, spinous processes of C7 and T1 --> triangular area at medial end of spine of scapula
Innervation: dorsal scapular nerve
Action: retract scapula and rotate it to depress glenoid cavity; fix scapula to thoracic wall
98
Rhomboid major
Spinous processes of T2-T5 vertebrae --> medial border of scapula from level of spine to inferior angle
Innervation: dorsal scapular nerve
Action: retract scapula and rotate it to depress glenoid cavity; fix scapula to thoracic wall
99
Rectus capitis posterior minor
Posterior tubercle of posterior arch of atlas --> medial inferior nuchal line
Innervation: suboccipital nerve
Action: extends skull on C1; stabilizes skull
100
Rectus capitis posterior major
Spinous process of axis --> inferior nuchal line (just lateral to minor)
Innervation: suboccipital nerve
Action: head extension (bilaterally); ipsilateral rotation (unilaterally)
101
Obliquus capitis inferior
Spinous process of axis --> lateral mass/transverse process of atlas
Innervation: suboccipital nerve
Action: ipsilateral neck rotation
102
Obliquus capitis superior
Lateral mass/transverse process of atlas --> lateral half of inferior nuchal line
Innervation: suboccipital nerve
Action: extend skull on C1 (bilaterally); contralateral rotation (unilaterally)
103
Opponens pollicis
Flexor retinaculum and tubercles of scaphoid and trapezium --> lateral side of 1st metacarpal
Innervation: recurrent branch of median nerve
Action: oppose thumb; draws 1st metacarpal medially to center of palm and rotates it medially
104
Abductor pollicis brevis
Flexor retinaculum and tubercles of scaphoid and trapezium --> lateral side of base of proximal phalanx of thumb
Innervation: recurrent branch of median nerve
Action: abducts thumb; helps oppose it
105
Flexor pollicis brevis
Flexor retinaculum and tubercles of scaphoid and trapezium --> lateral side of base of proximal phalanx of thumb
Innervation: recurrent branch of median nerve (superficial head), deep branch of ulnar nerve (deep head)
Action: flexes thumb at MCP joint
106
Adductor pollicis
Bases of 2nd and 3rd metacarpals, capitate, adjacent carpals (oblique head); anterior surface of shaft of 3rd metacarpal (transverse head) --> medial side of base of proximal phalanx of thumb
Innervation: deep branch of ulnar nerve
Action: adducts thumb toward lateral border of palm
107
Abductor digiti minimi (hand)
Pisiform --> medial side of base of proximal phalanx of 5th finger
Innervation: deep branch of ulnar nerve
Action: abducts 5th finger; assists in flexion of MCP joint
108
Flexor digiti minimi brevis (hand)
Hook of hamate and flexor retinaculum --> medial side of base of proximal phalanx of 5th finger
Innervation: deep branch of ulnar nerve
Action: flexes 5th MCP joint
109
Opponens digiti minimi
Hook of hamate and flexor retinaculum --> medial border of 5th metacarpal
Innervation: deep branch of ulnar nerve
Action: draws 5th metacarpal anterior and rotates it, bringing 5th finger into opposition with thumb
110
Lumbricals (hand)
Lateral two tendons of flexor digitorum profundus (as unipennate muscles) (1 and 2); medial three tendons of flexor digitorum profundus (as bipennate muscles) (3 and 4) --> lateral sides of extensor expansion of 2nd-5th fingers
Innervation: median nerve (1 and 2), deep branch of ulnar nerve (3 and 4)
Action: flex MCP joints; extend IP joints of 2nd-5th fingers
111
Dorsal interossei (1-4) (hand)
Adjacent sides of two metacarpals (as bipennate muscles) --> bases of proximal phalanges; extensor expansions of 2nd-4th fingers
Innervation: deep branch of ulnar nerve
Action: abduct 2nd-4th fingers from axial line; act with lumbricals in flexing MCP joints and extending IP joints
112
Palmar interossei (1-3)
Palmar surfaces of 2nd, 4th, and 5th metacarpals (as unipennate muscles) --> bases of proximal phalanges; extensor expansions of 2nd, 4th, and 5th fingers
Innervation: deep branch of ulnar nerve
Action: adduct 2nd, 4th, and 5th fingers towards axial line; assists lumbricals in flexing MCP joints and extending IP joints
113
Pectoralis major
Anterior surface of medial half of clavicle (clavicular head); anterior surface of sternum, superior six costal cartilages, aponeurosis of external oblique muscle (sternal head) --> lateral lip of intertubercular groove
Innervation: lateral and medial pectoral nerve
Action: flex shoulder (clavicular head); adduction, horizontal adduction, extension and medial rotation of shoulder (sternal head)
114
Pectoralis minor
3rd-5th ribs near their costal cartilages --> medial border and superior surface of coracoid process of scapula
Innervation: medial pectoral nerve (and lateral)
Action: stabilizes scapula (pulling inferiorly and anteriorly against thoracic wall) and elevates ribs during inspiration
115
Subclavius
Junction of 1st rib and its costal cartilage --> inferior surface of middle third of clavicle
Innervation: subclavian nerve
Action: depression of clavicle, elevation of 1st rib
116
Serratus anterior
External surfaces of lateral parts of ribs 1-8 --> anterior surface of medial border of scapula
Innervation: long thoracic nerve
117
Temporalis
Temporal lines on the parietal bone of the skull and the superior temporal surface of the sphenoid bone --> coronoid process of the mandible and retromolar fossa
Innervation: anterior trunk of mandibular nerve (CNV)
Action: elevates mandible (closing jaw); posterior fibers retract mandible
118
Masseter
Zygomatic arch and maxillary process of zygomatic bone --> angle and lateral surface of ramus of mandible, coronoid process
Innervation: anterior trunk of mandibular nerve (CNV)
Action: elevates mandible
119
Medial Pterygoid
Medial side of lateral pterygoid plate behind the upper teeth (deep head); pyramidal process of palatine bone and maxillary tuberosity (superficial head) --> medial angle of the mandible
Innervation: anterior trunk of mandibular nerve (CNV)
Action: acts synergistically with masseter to elevate mandible; contributes to protrusion; alternate unilateral activity produces smaller grinding movements
120
Lateral Pterygoid
Infratemporal surface of sphenoid bone (superior head); lateral pterygoid plate (inferior head) --> anterior side of the condyle (superior head); pterygoid fovea (inferior head)
Innervation: anterior trunk of mandibular nerve (CNV)
Action: bilaterally: protracts mandible and depresses chin; unilaterally, swings jaw toward contralateral side; alternate unilateral contraction produces larger lateral chewing movements
121
Sternocleidomastoid
Manubrium and medial portion of the clavicle --> mastoid process of the temporal bone, superior nuchal line
Innervation: spinal accessory nerve (CNXI; motor), C2 and C3 nerves (pain and proprioception)
Action: unilateral: same side lateral flexion and rotation so face is turned superiorly to opposite side; bilateral: extends neck at atlanto-occipital joints, flexes cervical vertebrae so chin approaches manubrium, or extends superior cervical vertebrae while flexing inferior cervical vertebrae so chin is thrust forward while head is level; may assist pump-handle action by elevating manubrium and medial end of clavicles with cervical vertebrae fixed
