Appendicular Muscles (Origin, Insertion and Action)

Pectoralis Major (Thorax Muscle)

Origin: Clavicle/ Sternum/ Costal Cartilage for Ribs

Insertion: Greater Tubercle of Humerus

Action: Flexes, adducts and medially rotates shoulder

Latissimus Dorsi (Thorax Muscle)

Origin: Spinous Process of lower thoracic and lumber vertebrae/ sacrum

Insertion: Intertubercular groove of humerus

Action: Extends/ adducts/ rotates shoulder medially

Trapezius (Thorax muscle)

Origin: Occipital Bone/ Vertebrae from C7-T12

Insertion: Clavicle/ Scapula (acromion and spine)

Action: Superior Portion- rotates scapula upward

Middle Portion- adduct scapula

Inferior Portion: depress scapula

**ALL stabilize scapula

Deltoid (Shoulder Muscle)

Origin: Clavicle/ scapula (acromion and spine)

Insertion: Deltoid Tuberosity of Humerus

Action: Lateral Fibers- abduct humerus

Anterior Fibers- flex and medially rotate humerus

Posterior Fibers- extend and laterally rotate humerus

Supraspinatus (shoulder muscle)

Origin: Supraspinous fossa of scapula

Insertion: Greater tubercle of humerus

Action: assists deltoid in abduction of shoulder

Infraspinatus (shoulder muscle)

Origin: Infraspinous fossa of scapula

Insertion: Greater tubercle of humerus

Action: Rotates the shoulder laterally

Teres minor (shoulder muscle)

Origin: Lateral border of scapula

Insertion: Greater tubercle of humerus

Action: Rotates/ extends shoulder laterally/ adduction

Subscapularis (shoulder muscle)

Origin: Subscapular fossa of scapula

Insertion: Lesser tubercle of humerus

Action: Medially rotates shoulder

Teres Major (shoulder muscle)

Origin: Inferior Angle of scapula

Insertion: Intertubercular groove of humerus

Action: extends shoulder/ assists in adduction/ medial rotation

Biceps Brachii Long Head (Upper arm muscles)

Origin: Scapula

Insertion: Radial tuberosity of radius

Action: flexes elbow and shoulder/ supinates forearm

Biceps Brachii Short Head (upper arm muscle)

Origin: Coracoid process of scapula

Insertion: radial tuberosity of radius

Action: Flexes elbow and shoulder/ supinates forearm

Brachialis (upper arm muscle)

Origin: Humerus

Insertion: Ulnar tuberosity

Action: Flexes elbow

Triceps Brachii Long Head (upper arm muscle)

Origin: Scapula

Insertion: Olecranon process of ulna

Action: extend elbow and shoulder/ adduction of shoulder

Triceps Brachii Lateral Head (upper arm muscle)

Origin: Humerus

Insertion: Olecranon process of ulna

Action: extend elbow

Triceps Brachii Medial Head (upper arm muscle)

Origin: Humerus

Insertion: Olecranon process of ulna

Action: extend elbow

Brachioradialis (forearm muscle/ superficial and anterior)

Origin: Humerus

Insertion: Base of styloid process of radius

Action: flexes arms at elbow/ raises arm to mid prone position

Pronator Teres (forearm muscle/ superficial and anterior)

Origin: Medial epicondyle of humerus/ ulna

Insertion: Radius

Action: pronates forearm and flexes elbow

Palmaris Longus (forearm muscles/ superficial and anterior)

Origin: Medial epicondyle of humerus

Insertion: Palmar aponeurosis (fascia in center of palm)

Action: WEAKLY flexes wrist

Flexor Carpi Radialis (forearm muscles/ superficial and anterior)

Origin: Medial epicondyle of humerus

Insertion: Metacarpals (2/3)

Action: flexes and abducts wrist in radial direction

Flexor Carpi Ulnaris (forearm muscles/ superficial and anterior)

Origin: Medial epicondyle of humerus

Insertion: Pisiform, hamate and metacarpal 5

Action: Flexes and adducts wrist in ulnar direction

Extensor Digitorum (forearm muscle/ superficial)

Origin: lateral epicondyle of humerus

Insertion: Distal and middle phalanges of each finger

Action: extends distal and middle phalanges/ extends wrist

Supinator (forearm muscles/ DEEP)

Origin: Lateral epicondyle of humerus

Insertion: Radius

Action: supinates forearm

Illiopsoas group (pelvic muscle)

Action: Psoas major, minor and Illiacus

Psoas major (pelvic muscles)

Origin: Transverse processes and bodies of lumbar vertebrae

Insertion: With illiacus to lesser trochanter of femur

Action: Flexion at hips or lumbar intervertebral joints

Illiacus (pelvic muscle)

Origin: Illiac fossa of illium/ sacrum

Insertion: With psoas major to lesser trochanter of femur

Action: Flexion at hip

Gluteus Maximus (pelvic muscles)

Origin: Illiac Crest of Illium/ sacrum/ coccyx

Insertion: IT Band/ gluteal tuberosity of femur

Action: extends and laterally rotates hips

Tensor Fasciae Latae (pelvic muscles)

Origin: Illiac Crest of Illium

Insertion: Tibia via IT Band

Action: Flexes/ abducts hip

Gracilis (thigh muscles/ medial)

Origin: Pubic bone

Insertion: medial shaft of tibia

Action: adducts hip/ medially rotates and flexes knee

Adductor magnus (thigh muscle/ medial)

Origin: Pubic Bone

Insertion: Linea Aspera of Femur

Action: Adducts hips

Superior Portion- Flexes hip

Inferior Portion- Extend hip

Adductor Longus (thigh muscles/ medial)

Origin: Pubic Bone

Insertion: Linea Aspera of Femur

Action: adduction/ flexion/ medial rotation of hip

Adductor Brevis (Thigh muscle/ medial)

Origin: Pubic Bone

Insertion: Linea Aspera of Femur

Action: adduction/flexion of hip

Sartorius (thigh muscle/ anterior)

Origin: Illium

Insertion: Medial Shaft of tibia

Action: weakly flexes knee/ weakly flexes and laterally rotates hip

Rectus Femoris (thigh muscle/ anterior)

Origin: Illium

Insertion: Tibial tuberosity of tibia

Action: All four quads extend the knee/ flexes hip

Vastus Lateralis (thigh muscle/ anterior)

Origin: Greater trochanter and linea aspera of femur

Insertion: Tibial tuberosity of tibia

Action: all four quads extend the knee

Vastus Medialis (thigh muscles/ anterior)

Origin: Linea Aspera of femur

Insertion: tibial tuberosity of tibia

Action: all four quads extend the knee

Vastus intermedius (thigh muscle/ anterior) (DEEP TO rectus femoris)

Origin: anterior/lateral surface of femur

Insertion: tibial tuberosity of tibia

Action: all four quads extend the knee

Tibialis Anterior (crural muscles)

Origin: Tibia

Insertion: Metatarsal 1 and medial cuneiform

Action: Dorsiflexes/ inverts ankle

Extensor Digitorum Longus (crural muscles/ anterior)

Origin: Tibia/ Fibula

Insertion: Middle and distal phalanges of toes

Action: Dorsiflexes ankle/ extends middle and distal phalanges of toes

Biceps Femoris Long Head (thigh muscle/ posterior)

Origin: Ischial tuberosity of Ischium

Insertion: Head of fibula/ lateral condyle of tibia

Action: flexes/ extends knee

Biceps Femoris Short Head (thigh muscle/ posterior)

Origin: Linea Aspera of femur

Insertion: Head of fibula/ lateral condyle of tibia

Action: Flexes knee

Semitendinosus (thigh muscle/ posterior)

Origin: Ischial tuberosity of ischium

Insertion: Tibia

Action: Flexes knees/ extends hip

Semimembranosus (thigh muscle/posterior)

Origin: Ischial tuberosity of Ischium

Insertion: Tibia

Action: Flexes knee/ extend hip

Fibularis Longus (crural muscles/ lateral)

Origin: fibula

Insertion: Metatarsal 1/ medial cuneiform

Action: plantarflexes/ everts ankle

Fibularis Brevis (crural muscle/ lateral)

Origin: Fibula

Insertion: Base of metatarsal 5

Action: Plantarflexes/ everts ankles

Gastrocnemius (crural muscle/ superficial)

Origin: lateral and medial condyle of femur

Insertion: Calcaneus via calcaneal tendon

Action: Plantarflexes ankles/ flexes knee

Soleus (crural muscle/superficial)

Origin: tibia/ fibula

Insertion: calcaneus via calcaneal tendon

Action: Plantarflexes ankle

Popliteus (crural muscle/ DEEP)

Origin: Lateral condyle of femur

Insertion: Proximal tibia

Action: flexes knee/ rotates tibia to unlock extended knee

Flexor Digitorum Longus (crural and DEEP muscle)

Origin: Posterior tibia

Insertion: distal phalanges of toes

Action: flexion of toes