Muscles that Move the Shoulder girdle

Trapezius

O - occipital bone (sup line), nuchal ligament, spines of c7 to T12

I - lateral third of clavicle, acromion and spine of scapula (3 heads)

A - steadies, elevates, depresses, retracts scapula

 

Levator scapulae

O - Transverse processes of C1-4

I - Super vert border of scapula

A - elevates scapula, bends neck laterally

 

Rhomboids (minor and major)

O - ligamentum nuchae, spines of C7 to T5

I - medial border of scapula

A - retract s, elevates scapula

 

Serratus anterior

O - Ribs 1-8, midway betw angles + costal cartilages

I - medial border, infer angle of scapula

A - protracts scapula

 

Pectoralis minor

O - Ribs 3-5

I - coracoid process of scapula

A -depresses, rotates scapula down

 

Pectoralis major

O - medial half of clavicle, sternum, ribs 1-6

I - lat. crest of intertubercular groove of humerus

A - depresses shoulder

 

Latissimus dorsi

O - Spines of T7 to sacrum, ribs 7-12, post iliac crest

I - intertubercular groove of humerus

A - depresses, retracts scapula

 

Intercostals

O Ext - inf border rib

Int - super border rib

I - Ext - super border rib

Int - inf border rib

A - Ext - elevate ribs - assist inspiration

Int - draw ribs together - force expiration

 

Move the Head

Sternocleidomastoid

O sternum and clavicle

I - mastoid process of temporal

A - both - flex neck; one - rotate head

 

Scalenes

O - transverse processes - cervical vertebrae

I - rib 1

A -flexes, rotates head, aids inspiration

 

splenius capitas

O - spinous processes C7-T4

I - mastoid process, lat. sup. nuchal line

A - extends, rotates head

 

 

Move the humerus at shoulder joint

 

Rotator Cuff

supraspinatus

O - supraspinous fossa of scapula

I - greater tuberosity of humerus

A - stabilizes joint, abducts arm

 

infraspinatus

O - infraspinous fossa

I - greater tuberosity of humerus

A - stabilizes joint; laterally rotates, some adduction

 

teres minor

O - superior lateral border of scapula

I - greater tuberosity of humerus

A - stabilizes joint; laterally rotates arm, extends, adducts

 

subscapularis

O - subscapular fossa

I - lesser tuberosity

A - stabilizes joint; medially rotates arm

 

Other Contributing Muscles

Teres major

O - inferior angle and lat border of scapula

I - medial crest of intertubercular groove

A - adducts, extends, medially rotates arm

 

Deltoid

O - Clavicle (lateral third); acromion process and spine of scapula

I - deltoid tuberosity of humerus

A - Clavicular head: flexes, med. rotates arm

acromial head: abducts arm

spinous head: extend, lat. rotates arm

 

Pectoralis major

O and I - SEE ABOVE

A - adducts, flexes, and rotates arm medially,

 

Latissimus dorsi

O and I - SEE ABOVE

A - extends, adducts, medially rotates humerus

 

Coracobrachialis

O - coracoid process

I - middle medial third of humerus

A - flexes, weakly adducts arm

Muscles that move Arm

Biceps brachii

O - Long Head: supraglenoid tubercle of scapula

short head: coracoid process of scapula

I - radial tuberosity, bicipital aponeurosis

A - flexes elbow; supinates forearm, weak arm flexor

Brachialis

O - anterior distal surface of humerus

I - tuberosity and coronoid process of ulna

A - flexes elbow

Brachioradialis

O - upper 2/3 lat supracondylar ridge of humerus

I - base of styloid process of radius

A - flexes elbow, semisupinates/pronates

Triceps brachii

O - Long head: infraglenoid tubercle

Lateral Head: post/lat humerus above radial groove

Medial Head: post. humerus below radial groove

I - olecranon process of ulna

A - extends elbow, adducts arm

Supinator

O - lateral epicondyle of humerus

I - lateral surface of proximal third of radius

A - supinates forearm

Pronator teres

O - medial supracondylar ridge of humerus, coronoid process of ulna

I - midlateral surface of radius

A - pronates forearm, flexes elbow

Pronator quadratus

O - ant distal end of ulna

I - ant distal end of radius

A - pronates forearm

 

 

Muscles that Move the Wrist

Flexor carpii radialis

O - medial epicondyle of humerus

I - ant. base of 2nd, 3rd metacarpals

A - flexes and abducts wrist

Flexor carpi ulnaris

O - medial epi of humerus

I - ant carpals, base of 5th meta

A - flexes and adduct wrist

Palmaris longus

O - medial epi of humerus

I - palmar aponeurosis

A - flexes wrist

Extensor carpi radialis longus

O - lateral epi

I - Base of 2nd metas

A - extends and abducts wrist

 

Extensor carpi ulnaris

O - lateral epi

I - Base of 5th meta

A - extends and adducts

 

 

 

 

 

Move the Fingers

Flexor digitorum superficialis

O - medial epi, coronoid process, radius

I - tendons of fingers, middle phlanges

A - flexes fingers

Extensor digitorum

O - lateral epi

I - posterior surface of phlanges 2-5

A - extends fingers and wrist

 

Move the Thumb

Flexor and extensor pollicis

O - post. radius/ant carpals

I - Base of distal phalanx 1 - post./lat.

A - flexes or extends thumb

Flexor/Extensor retinaculae

heavy connective tissue

connects lateral border of radius w/ medial portion of styloid process of ulna

gives off branches of connective tissue to wrist bones

---> series of sheaths which cover tendons of extensor muscles of fingers

 

Muscles of the Abdominal Wall

External Oblique

O - outer surfaces of lower 8 ribs

I - ant. iliac crest and linea alba

A - tenses abdominal wall and compresses abdominal contents, lateral rotation and flexion of vertebral column

Internal Oblique

O - crest of ilium

I - cartilages of lower ribs; linea alba

A - same as Ext oblique

Transversus abdominus

O - Costal cartilages of lower ribs, processes of lumbar vertebrae, lip of iliac crest

I - linea alba, crest of pubis

A - same as above

Rectus abdominus

O - crest of pubis and symphysis pubis

I - xiphoid process and costal cartilages

A - same as above

 

EXTEND THE VERTEBRAL COLUMN

erector spinales (large group of muscles)

Spinalis thoracis

semispinalis thoracis

semispinalis cervicus

O -   spinous processes of T11-12, L1-2

transverse processes of T6-10

"           "           "           T1-6

I-     Spinous processe of T1-8

       "           "           " C6-7, T1-4

       "           "           " C2-5

A - extend and rotate vertebral column

Move the Thigh

Anterior group - Flexors

Psoas major

O - bodies, transverse processes lumbar vert.

I - lesser trochanter of femur

A - flexes and rotates thigh lat., flexes vert.

Iliacus

O - iliac fossa of ilium

I - lesser trochanter of femur

A - flexes and rotates thigh lat., flexes vert.

Posterior group

Extensor

Gluteus maximus

O - iliac crest, sacrum, coccyx

I - gluteal tuberosity of femur

A - extends and rotates thigh lat.

Abductors

Gluteus medius

O - lateral ilium

I - greater trochanter of femur

A - abducts thigh

Gluteus minimus

O - lateral ilium

I - greater trochanter of femur

A - abducts thigh

Tensor fasciae latae

O - anterior iliac crest

I - tibia via iliotibial tract

A - abducts, flexes thigh

Medial group

Adductors (Groin)

Adductor longus

O - pubic crest near symphysis pubis

I - linea aspera of femur

A - adducts, flexes thigh

Adductor magnus

O - Ischial tuberosity and pubis

I - linea aspera of femur, adductor tubercle

A - adducts, ant. part - flexes/post. part - extends thigh

Gracilis

O – pubic ramus

I - medial surface of tibial shaft

A - adducts thigh and flexes leg at knee

Lower Leg

Flexors (Hamstring)

Biceps femoris

O - long - Ischial tuberosity, short - linea aspera of femur

I - head of fibula and lateral condyle of tibia

A - flexes knee, extends thigh

Semitendonosus

O - Ischial tuberosity

I – medial, proximal surface of tibia

A - same

Semimembranous

O - Ischial tuberosity

I - Medial condyle of tibia

A - same

 

 

 

Flexors (cont)

Sartorius

O - anterior superior iliac spine

I – medial, proximal surface of tibia

A - flexes leg and thigh, rotates thigh laterally (crosses leg)

Extensors

Quadriceps femoris

Rectus femoris

O - ant. inf. iliac spine

I - patella by common tendon; continues as ligament to tibial tuberosity

A - extends leg at knee

Vastus lateralis, intermedius, medialis

O - ///Greater trochanter/lat. surface femur

//Medial surface femur

///Anterior/medial surface femur

I - same as rectus femoris

A - extends leg at knee

Muscles of Ankle, Foot, Toes

Anterior

Dorsiflexors

Tibialis anterior

O - lateral condyle/surface of tibia

I - 1st meta tarsal, 1st cuneiform

A - dorsiflexion/inversion of foot

Peroneus tertius

O - distal third ant. fibula

I - 5th metatarsal

A - dorsiflexion/eversion of foot

Extensor digitorum longus

O - Lateral condyle tibia, ant. surface fibula

I - dorsal surfaces of 2nd,3rd phlanges of 4 lateral toes

A - dorsiflexion/eversion, toe extension

Posterior

Plantar flexors

gastrocnemius

O - lateral/medial condyles of femur

I - posterior surface of calcaneus

A - plantar flexion, flexion of leg at knee

soleus

O - Head/shaft of fibula, post. tibial surface

I - posterior surface calcaneus

A - plantar flexion of foot

Flexor digitorium longus

O - posterior surface of tibia

I - distal phlanges of 4 lateral toes

A - plantar flexion, inversion of foot, flexion of four lateral toes

Tibialis posterior

O - lat. condyle, post. tibial/fibular surface

I - Tarsal and metatarsal bones

A - plantar flexion and inversion of foot

Lateral

Peroneus longus

O - lat. condyle of tibia. fibular head/shaft

I - tarsal and metatarsals

A - plantar flexion and eversion of foot