Appendicular Muscles (Upper and Lower Extremity)

Biceps Brachii

Origin:

long head; superior margin of glenoid fossa of scapula

short head: coracoid process of the scapula

Insertion: radial tuberosity of radius; fascia of medial forearm via bicipital aponeurosis

Action: flexion and supination of forearm; flexion of arm

Brachialis

Origin: anterior surface of the humerus

Insertion: coronoid process of the ulna

Action: flexion of forearm

Coracobrachialis

Origin: coracoid process of scapula

Insertion: medial surface of humerus

Action: flexion and adduction of arm

Triceps Brachii

Origin:

Long Head: inferior margin of glenoid fossa in scapula

Lateral Head: posterior surface of humerus

Medial Head: posterior surface of humerus, inferior to origin of lateral head

Insertion: olecranon process of the ulna

Action: extension of forearm; long head extends and adducts arm

Pronator Treres

Origin: medial epicondyle of humerus; coronoid process of the ulna

Insertion: lateral surface of the radius

Action: pronation and flexion of the forearm

Flexor Carpi Radialis

Origin; medial epicondyle of humerus

Insertion: base of 2nd and 3rd metacarpals

Action: flexion and abduction of the wrist

Flexor Carpi Ulnaris

Origin: medial epicondyle of the humerus; olecranon process of the ulna

Insertion: pisiform; hamate; base of 5th metacarpal

Action: flexion and adduction of the wrist

Palmaris Longus

Origin: medial epicondyle of humerus

Insertion: flexor retinaculum; palmar aponeurosis

Action: flexion of the wrist

Flexor Digitorum Superficialis

Origin: medial epicondyle of the humerus; coronoid process of the ulna; anterior surface of the radius

Insertion: middle phalanges of medial 4 digits

Action: flexion of fingers and wrist

Flexor Pollicis Longus

Origin: anterior surface of radius; interosseous membrane

Insertion: distal phalanx of thumb (1st digit)

Action: flexion of thumb and wrist

Flexor Digitorum Profundus

Origin: medial and anterior surface of ulna; coronoid process; interosseous membrane

Insertion: distal phalanges of medial 4 digits

Action: flexion of distal phalanges and wrist

Pronator Quadratus

Action: medial surface of ulna at the distal end

Insertion: anterolateral surface of radius at the distal end

Action: pronation of forearm

Brachioradialis

Origin: lateral supracondylar ridge of humerus

Insertion: lateral surface of distal radius

Action: flexion of forearm

Extensor Carpi Radialis Longus

Origin: lateral supracondylar ridge of humerus

Insertion: base of 2nd metacarpal

Action: extension and abduction of the wrist

Extensor Carpi Radialis Brevis

Origin: lateral epicondyle of humerus

Insertion: base of 3rd metacarpal

Action: extension and abduction of the wrist

Extensor Digitorum

Origin: lateral epicondyle of humerus

Insertion: extensor expansions of medial 4 digits

Action: extension of fingers and wrist

Extensor Digiti Minimi

Origin: lateral epicondyle of humerus

Insertion: extensor expansion of 5th digit (pinky)

Action: extenion of the 5th digit and the wrist

Extensor Carpi Ulnaris

Origin: lateral epicondyle of humerus; posterior surface of ulna

Insertion: base of 5th metacarpal

Action: extension and adduction of the wrist

Anconeus

Origin; lateral epicondyle of humerus

Insertion: lateral surface of olecranon process of ulna

Action: weak extension of forearm

Supinator

Origin: lateral epicondyle of humerus; proximal ulna

Insertion: posterior, lateral, and anterior surfaces of proximal radius

Action: supination of the forearm

Abductor Pollicis Longus

Origin: posterior surfaces of radius and ulna; interosseous membrane

Insertion: metacarpal of thumb

Action: abducts and extends thumb

Extensor Pollicis Longus

Origin: posterior surface of the ulna; interosseous membrane

Insertion: distal phalanx of thumb (1st digit)

Action: extension of the thumb

Gluteus Maximus

Origin: iliac crest; lateral surface of ilium; posterior surface of sacrum and coccyx

Insertion: iliotibial tract; gluteal tuberosity of femur

Action: extension and lateral rotation of the thigh; powerful

Gluteus Medius

Origin: lateral surface of ilium

Insertion: greater trochanter of femur, lateral surface

Action: abduction and medial rotation of thigh; steadies the pelvis during walking

Gluteus Minimus

Origin: lateral surface of the ilium, inferior to origin of gluteus medius

Insertion: greater trochanter of femur, anterior surface

Action: abduction and medial rotation of the thigh; steadies the pelvis during walking

Piriformis

Origin: anterolateral surface of sacrum

Insertion: greater trochanter of femur, superior surface

Action: abduction and lateral rotation of the thigh

Iliacus

Origin: iliac fossa; anterior surface of sacrum

Insertion: lesser trochanter of femur

Action: flexion of thigh; flexion of trunk

Psoas Major

Origin: bodies and transverse processes of vertebrae T12 - L5

Insertion: lesser trochanter of femur

Action: felxion of the thigh, flexion of the trunk

Tensor Fascia Latae

Origin: anterior portion of the iliac crest and anterior superior iliac spine

Insertion: iliotibial tract

Action: flexes, abducts, and medially rotates the thigh; stabilizes hip and knee joint

Sartorius

Origin: anterior superior iliac spine

Insertion: medial surface of tibia, near the knee joint

Action: flexion, abduction, and lateral rotation of the thigh; flexion of leg

Rectus Femoris

Origin: anterior inferior iliac spine; superior margin of the acetabulum

Insertion: patella via the quadriceps tendon and tibial tuberosity via the petellar ligament

Action: extension of leg; flexion of thigh

Vastus Medialis

Origin: interochanteric line and medial lip of linea aspera

Insertion: petella via the quadriceps tendon and tibial tuberosity via the patella ligament

Action: extension of leg

Vastus Intermedius

Origin: anterolateral surface of femur

Insertion: patella via the quadriceps tendon and tibial tuberosity via the patellar ligament

Action: extension of leg

Vastus Lateralis

Origin: greater trochanter and lateral lip of linea aspera of femur

Insertion: patella via the quadriceps tendon and tibial tuberosity via the patellar ligament

Action: extension of leg

Biceps Femoris

Origin:

Long Head: ishcial tuberosity

Short Head: linea aspera and lateral supracondylar line of femur

Insertion: head of fibula, lateral surface

Action: flexion and lateral rotation of leg; long head extends the thigh

Semitendinosus

Origin: ischial tuberosity of ischium

Insertion: medial surface of tibia, near the knee joint

Action: extension of thigh; flexion and medial rotation of leg

Semimembranosus

Origin: ischial tuberosity of ischium

Insertion: medial condyle of tibia

Action: extension of thigh; flexion and medial rotation of leg

Pectineus

Origin: pectineal line of pubis

Insertion: pectineal line of femur

Action: adduction, flexion, and medial rotation of thigh

Adductor Longus

Origin: body of pubic bone

Insertion: linea aspera of femur

Action: adduction, flexion, and medial rotation of thigh

Adductor Magnus

Origin: ischial and pubic rami; ischial tuberosity

Insertion: linea aspera and adductor tubercle of femur

Action:

Superior Portion: adduction, flexion, and medial rotation of thigh

Inferior Portion: extension and lateral rotation of thigh

Adductor Brevis

Origin: body and ramus of pubis

Insertion: pectineal line and linea aspera of femur

Action: adduction, flexion, and medial rotation of thigh

Gracilis

Origin: body and inferior ramus of pubic bone

Insertion: medial surface of tibia, near the knee joint

Action: adduction of thigh; flexion and medial rotation of leg

Tibialis Anterior

Origin: lateral condyle and proximal lateral surface of tibia; interosseous membrane

Insertion: medial cuneiform and first metatarsal

Action: doriflexion and inversion of foot

Extensor Digitorum Longus

Origin: lateral condyle of tibia; medial surface of proximal fibula; interosseous membrane

Insertion: middle and distal phalanges of digits 2-5

Action: extension of toes; dorsification of foot

Extensor Hallucis Longus

Origin: anterior surface of fibula; interosseous membrane

Insertion: distal phalanx of great toe (hallux)

Action: extension of great toe; dorsification of foot

Fibularis (proneus) Longus

Origin: head and lateral surface of fibula

Insertion: 1st metatarsal and medial cuneiform

Action: eversion and plantar flexion of foot

Fibularis (proneus) Brevis

Origin: lateral surface of fibula

Insertion: 5th metatarsal

Action: eversion and plantar flexion of foot

Gastrocnemius

Origin:

Lateral Head: lateral condyle of femur

Medial Head: posterior part of medial condyle; popliteal surface of femur

Insertion: calcaneus via calcaneal (Achilles) tendon

Action: plantar flexion of foot; flexion of leg

Soleus

Origin: head of fibula; posterior surface of fibula; posteromedial aspect of tibia

Insertion: calcaneus via calcaneal tendon

Action: plantar flexion of foot

Plantaris

Origin: lateral supracondylar line of femur

Insertion: posterior part of calcaneus

Action: assists in plantar flexion of foot and flexion of leg

Popliteus

Origin: lateral condyle of femur

Insertion: posterior surface of proximal tibia

Action: flexion and medial rotation of leg

Tibialis Posterior

Origin: posterior surfaces of tibia and fibula; interosseous membrane

Insertion: navicular, cuboid, and cuneiform bones; metatarsals 2-4

Action: plantar flexion and inversion of foot