Final muscles Flashcards
Lat dorsi origin
Spinous processes of inferior 6 thoracic vertebrae, thoracolumbar fascia, iliac crest, and inferior 3 or 4 ribs (~inferior angle of scapula)
lat dorsi insertion
floor of intertubercular sulcus of humerus
lat dorsi innervation
thoracodorsal nerve C6 C7 C8
lat dorsi action
Extends, adducts, and medially rotates humerus; raises body towards arms during climbing
trapezius origin
Medial third of superior nuchal line; external occipital protuberance; nuchal ligament; spinous processes of C7-T12 vertebrae
trapezius insertion
lateral third of clavicle; acromion and spine of scapula
trapezius innervation
spinal accessory n. (CN XI) (motor fibers) and C3, C4 spinal nerves (pain and proprioceptive fibers
trapezius actions
Descending: elevates
Ascending: depresses
Middle/all parts together: retracts scapula
Descending and ascending: rotate glenoid cavity superiorly
SCM origin
Sternal head: anterior surface of manubrium of sternum
Clavicular head: superior surface of medial third of clavicle
SCM insertion
Lateral surface of mastoid process of temporal bone and lateral half of superior nuchal line
SCM innervation
Spinal accessory nerve (CN XI, motor); C2 and C3 nerves (pain and proprioception)
SCM action
Unilateral contraction: tilts head to same side (i.e. laterally flexes neck) and rotates it so face is turned superiorly toward opposite side Bilateral contraction: (1) extends neck at atlanto-occipital joints, (2) flexes cervical vertebrae so that chin approaches manubrium, (3) extends superior cervical vertebrae while flexing inferior vertebrae so chin is thrust forward with head kept level
With cervical vertebrae fixed, may elevate manubrium and medial ends of clavicles, assisting pump-handle action of deep respiration
serratus anterior origin
External surfaces of lateral parts of 1st- 8th ribs
serratus anterior insertion
anterior surface of medial border of scapula
serratus anterior innervation
Long thoracic nerve (C5, C6, C7)
serratus anterior action
Protracts scapula and holds it against thoracic wall, rotates scapula superiorly
rhomboid M origin
Spinous processes of T2-T5 vertebrae
rhomboid M insertion
Medial border of scapula from level of spine to inferior angle
rhomboid M innervation
dorsal scapular C4 C5
rhomboid M action
retract scapula and rotate glenoid cavity inferiorly; fix scapula to thoracic wall
rhomboid m origin
nuchal ligament; spinous processes of C7 and T1 vertebrae
rhomboid m insertion
smooth triangular area at end of medial spine
rhomboid m innervation
dorsal scapular C4 C5
rhomboid m action
retract scapula and rotate glenoid cavity inferiorly; fix scapula to thoracic wall
supraspinatus origin
supraspinous fossa of scapula
supraspinatus insertion
superior facet of greater tubercle of humerus
supraspinatus innervation
suprascapular nerve C4-C5
supraspinatus action
initiates and assists deltoid in abduction of arm and acts with rotator cuff muscles
infraspinatus origin
infraspinous fossa of scapula
infraspinatus insertion
middle facet of greater tubercle of humerus
infraspinatus innervation
suprascapular nerve C5-C6
infraspinatus action
laterally rotates arm; acts with rotator cuff muscles
teres minor origin
middle part of lateral border of scapula
teres minor insertion
inferior facet of greater tubercle of humerus
teres minor innervation*
axillary nerve C5-C6
teres minor action
laterally rotates arm; acts with rotator cuff muscles
teres major origin
posterior surface of inferior angle of scapula
teres major insertion
medial lip of intertubercular sulcus of humerus
teres major innervation
lower subscapular C5 C6
teres major action
adducts and medially rotates arm
pec major origin Clavicular head
anterior surface of medial half of clavicle
pec major origin Sternocostal head
anterior surface of sternum, superior 6 costal cartilages, aponeurosis of external oblique m.
pec major insertion
lateral lip of intertubercular sulcus of humerus
pec major innervation
lateral and medial pectoral nerves; clavicular head C5 C6, sternocostal head C7 C8 T1
pec major action
adducts and medially rotates humerus. Clavicular head flexes humerus; SC head extends it from flexed position
pec minor origin
3rd- 5th ribs near their costal cartilages
pec minor insertion
medial border and superior surface of coracoid process of scapula
pec minor innervation
medial pectoral nerve C8 T1
pec minor action
stabilizes scapula by drawing it inferiorly and anteriorly against thoracic wall
serratus anterior origin
external surfaces of lateral parts of 1-8 ribs
serratus anterior insertion
anterior surface of medial border of scapula
serratus anterior innervation*
long thoracic nerve C5-C7
serratus anterior action
protracts scapula and holds it against thoracic wall; rotates scapula superiorly
deltoid origin
lateral third of clavicle, acromion (middle) and spine of scapula (posterior)
deltoid insertion
deltoid tuberosity of humerus
deltoid innervation*
axillary nerve C5-C6
deltoid action
anterior: flexes and medially rotates arm
middle: abducts arm
posterior: extends and laterally rotates arm
subscapularis origin
subscapular fossa (anterior surface of scapula)
subscapularis insertion
lesser tubercle of humerus
subscapularis innervation
upper and lower subscapular nerves C5-C7
subscapularis action
medially rotates arm; holds head of humerus in GC
biceps brachii origin
short: tip of coracoid process
long: supraglenoid tubercle of scapula
biceps brachii insertion
tuberosity of radius and fasica of forearm via bicipital aponeurosis
biceps brachii innervation
musculotaneous nerve C5-C7
biceps brachii action
supinates forearm and when supine, flexes it; short head resists dislocation of shoulder
brachialis origin
distal half of anterior surface of humerus
brachialis insertion
coronoid process and tuberosity of ulna
brachialis innervation
musculotaneous n. C5-C6 and radial nerve C5 *C7
brachialis action
relatively weak flexion of forearm; maximal when forearm is mid-pronated position
triceps brachii origin
long head: infraglenoid tubercle
lateral: posterior surface of humerus, superior to radial groove
medial: posterior surface of humerus, inferior to radial groove
triceps brachii insertion
proximal end of olecranon of ulna and fascia of forearm
triceps brachii innervation
radial n. C6-C8
triceps brachii action
chief extensor of forearm; long head resists dislocation of the humerus - especially important during adduction
FDS origin
humero-ulnar: medial epicondyle & coronoid process
radial: superior half of anterior border
FDS insertion
middle phalanges of medial four digits
FDS innervation
median n. C7-T1
FDS action
flexes middle phalanges at PIP of middle 4 digits; more strongly, flexes proximal phalanges at MCP joints
FDP origin
proximal 3/4 of medial and anterior surfaces of ulna and interosseous membrane
FDP insertion
medial: distal phalanges of 4 and 5
lateral: distal phalanges of 2 and 3
FDP innervation
medial: ulnar nerve C8 T1
lateral: anterior interosseous n. from median nerve C8 T1
FDP action
medial: flexes distal phalanges of 4 and 5 at DIP
lateral: flexes distal phalanges of 2 and 3 at DIP
extensor digitorum origin (hand)
lateral epicondyle of humerus
extensor digitorum insertion
extensor expansions of medial 4 digits
extensor digitorum innervation
deep branch of radial nerve C7 C8
extensor digitorum action
extends medial 4 digits at MCP, secondarily at IP joints
gluteus maximus origin
ilium posterior to posterior to gluteal line; dorsal surface of sacrum and coccyx; sacrotuberous ligament
glut max insertion
most in IT band, some on gluteal tuberosity
glut max innervation
inferior gluteal nerve L5 S1 S2
glut max action
extends thigh from flexed position and laterally rotates; steadies thigh, assists in rising from seated position
glut medius origin
external surface of ilium between anterior and posterior gluteal lines
glut medius insertion
lateral surface of GT
glut med innervation
sup gluteal n. L5 S1
glut min origin
posterior surface of ilium between anterior and inferior gluteal lines
glut min insertion
lateral surface of GT
glut min innervation
sup. gluteal n L5 S1
glut med action
abduct and medially rotate thigh; keeps pelvis level when same side limb is weight bearing and advance unsupported side in swing phase
glut min action
abduct and medially rotate thigh; keeps pelvis level when same side limb is weight bearing and advances unsupported side in swing
biceps femoris origin
long: ischial tuberosity
short: linea aspera and lateral supracondylar line of femur
biceps femoris insertion
lateral side of head of fibula
biceps femoris innervation
LH: tibial n. L5 S1 S2
SH: common fibular L5 S1 S2
biceps femoris action
flexes leg and laterally rotates it when knee is flexes; extends thigh
semitendinosus origin
ischial tuberosity
semitend insertion
pes anserine
semiten innervation
tibial n. L5 S1 S2
semitend action
extends thigh; flex leg and rotate it medially when knee is flexed
when thigh and leg are flexed, these muscles can extend trunk
semimembranosus origin
ischial tuberosity
semimembranosus insertion
posterior part of medial condyle of tibia; forms oblique popliteal lig
semimem innervation
tibial L5 S1 S2
semimem action
extends thigh; flexes leg and rotates it medially when knee is flexed
can extend trunk when thigh and leg are flexed
adductor magnus origin
add: inferior ramus of pubis, ramus of ischium
HS: ischial tuberosity
add magnus insertion
Add: gluteal tuberosity, linea aspera, supracondylar line of femur
HS: adductor tubercle
add mangus innervation
Add: obturator L2 L3 L4 posterior branches
HS: tibial L4
add magnus action
adducts thigh
add: flexes thigh
HS: extends thigh
adductor longus origin
body of pubis inferior to pubic crest
adductor longus insertion
middle third of linea aspera of femur
adductor longus innervation
obturator n. anterior division L2 L3 L4
adductor longus action
adducts thigh
gracilis origin
body and inferior ramus of pubis
gracilis insertion
superior part of medial surface of tibia
gracilis innervation
obturator n. L2 L3
gracilis action
adducts thigh; flexes leg; helps rotate leg medially
psoas major origin
sides of T12 L5 vertebrae and IVD, transverse processes of lumbar vertebrae
psoas major insertion
lesser trochanter of femur
psoas major innervation
ant rami of lumbar nerve L1-L3
psoas major action
act conjointly in flexing thigh at hip and stabilizing it
psoas minor origin
sides of T12-L1 and IVD
psoas minor insertion
pectineal line, iliopectineal emenince via iliopectineal arch
psoas minor innervation
ant rami lumbar L1 L2
psoas minor action
act conjointly in flexing thigh at hip and stabilizing it
iliacus origin
iliac crest and iliac fossa, ala of sacrum and anterior sacro-iliac ligaments
iliacus insertion
tendon of psoas major, LT, and femur distal to it
iliacus innervation
femoral n. L2 L3
iliacus action
act conjointly in flexing thigh at hip and in stabilizing this joint
rectus femoris origin
AIIS and ilium superior to acetabulum
rectus femoris insertion
quad tendon and independently to patella; indirectly to patellar ligament
rectus femoris innervation
femoral n. L2 L3 L4
rectus femoris action
extend leg at knee joint; steadies hip joint and helps iliopsoas flex thigh
vastus lateralis origin
GT and lateral lip of linea aspera of femur
vastus lateralis insertion
quad tendon, independent patella, indirectly patellar lig to tibial tuberosity, tibia and patella via aponeurosis
vastus lateralis innervation
femoral n. L2-L4
vastus lateralis action
extend leg at knee joint; steadies hip joint and helps iliopsoas flex thigh
vastus medialis origin
intertrochanteric line and medial lip of linea aspera
vastus medialis insertion
quad tendon…
vastus medialis innervation
femoral n. L2-L4
vastus medialis action
extends leg at knee joint, helps iliopsoas flex thigh, steadies hip
vastus intermedius origin
anterior and lateral surfaces of shaft of femur
vastus intermedius insertion
quad tendon…
vastus intermedius innervation
femoral L2-L4
vastus intermedius action
extends leg at knee joint
tibialis anterior origin
lateral condyle and superior half of lateral surface of tibia and IO
tibialis anterior insertion
medial and inferior surfaces of medial cuneiform and base of 1st metatarsal
tibialis anterior innervation
deep fibular n. L4 L5
tibialis anterior action
DF of ankle and inversion of foot
peroneus longus origin
head and superior 2/3 of lateral surface of fibula
peroneus longus insertion
base of 1st metatarsal and medial cuneiform
peroneus longus innervation
superficial fibular n. L5-S2
peroneus longus action
everts foot, weak PF; perception
peroneus brevis origin
inferior two thirds of lateral surface of fibula
peroneus brevis insertion
dorsal surface of tuberosity on lateral side of base of 5th metatarsal
peroneus brevis innervation
superficial fibular n. L5-S2
peroneus brevis action
weak PF, eversion, perception
gastrocnemius origin
lateral: lateral aspect of lateral condyle of femur
medial: popliteal surface of femur; superior to medial condyle
gastrocnemius insertion
posterior surface of calcaneus via calcaneal tendon
gastroc innervation
tibial n. S1 S2
gastroc action
PF ankle when knee is extended; raises heel during walking; flexes leg at knee joint
soleus origin
posterior aspect of head and superior 1/4 of posterior surface of fibula; soleal line and middle 1/3 of medial border of tibia; tendinous arch extending between boney attachments
soleus insertion
posterior surface of calcaneus via calcaneal tendon
soleus innervation
tibial n. S1 S2
soleus action
PF ankle independent of position of knee; steadies leg on foot
FHL origin
inferior 2/3 of posterior surface of fibula; inferior part of IO
FHL insertion
base of distal phalanx of great toe
FHL innervation
tibial n. S2 S3
FHL action
flexes great toe at all joints, weak PF, supports medial longitudinal arch
FDL origin
medial part of posterior surface of tibia inferior to soleal line; broad tendon to fibula
FDL insertion
base of distal phalanges of lateral 4 digits
FDL action
flexes lateral 4 digits; PF; supports longitudinal arches
Tibialis posterior origin
IO; posterior surface of tibia inferior to soleal line; posterior surface of fibula
tibialis posterior insertion
tuberosity of navicular, cuneiform, cubdoi, and susentaculum tali of calcaneus; bases of 2-4 metatarsals
tib posterior innervation
tibial nerve L4 L5
tib posterior action
PF; inversion
SCM origin
sternal: anterior surface of manubrium of sternum
clavicular: superior surface of medial third of clavicle
SCM insertion
lateral surface of mastoid process of temporal bone and lateral half of superior nuchal line
SCM innervation
spinal accessory and C2 C3 pain and proprioception
