Lab Activity 11 Group II Muscles Martini Chapter

Lab Activity 11: Group II Muscles Martini Chapter 11 Portland Community College BI 231

Pronator Teres • Action: Pronates and flexes forearm • Origin: Medial epicondyle of humerus; coronoid process of ulna • Insertion: Lateral surface of radius Anterior, Superficial Layer 2

Flexor Carpi Radialis • Action: Flexes wrist and elbow and abducts wrist • Origin: Medial epicondyle of humerus • Insertion: Base of metacarpal of the second digit Anterior, Superficial Layer 3

Palmaris Longus • Action: Weak flexion of wrist, tenses skin of palm • Origin: Medial epicondyle of humerus • Insertion: Flexor retinaculum; palmar aponeurosis Anterior, Superficial Layer 4

Flexor Carpi Ulnaris • Action: Flexes and adducts wrist • Origin: Medial epicondyle of humerus; olecranon process of ulna • Insertion: medial carpal bones; metacarpal of 5 th digit • Anterior, Superficial Layer 5

Flexor Digitorum Superficialis • Action: Flexes fingers and wrist • Origin: Medial epicondyle of humerus; coronoid process of ulna; anterior surface of radius • Insertion: Middle phalanges of medial 4 digits 6 Anterior, Middle Layer

Flexor digitorum profundus • Action: Flexion of wrist and fingers • Origin: Medial and anterior surfaces of ulna; interosseous membrane • Insertion: Distal phalanges of fingers 7

Flexor Pollicis Longus • Action: Flexes thumb and wrist • Origin: Middle half of radius; interosseous membrane, coronoid process of ulna • Insertion: Distal phalanx of thumb 8 Anterior, Deepest Layer

Brachioradialis • Action: Flexes forearm • Origin: Lateral supracondylar ridge • Insertion: Lateral surface of distal radius 9 Posterior, Superficial Layer

Extensor Carpi Radialis Longus • Action: Extends and abducts hand • Origin: Lateral supracondylar ridge of humerus • Insertion: Second metacarpal 10 Posterior, Superficial Layer

Extensor Carpi Radialis Brevis • Action: Extends and abducts hand • Origin: Lateral epicondyle of humerus • Insertion: Third meta carpal 11 Posterior, Superficial Layer

Extensor Digitorum • Action: Extends fingers and hand • Origin: Lateral epicondyle of humerus • Insertion: Extensor expansions of medial four digits 12 Posterior, Superficial Layer

Extensor Digiti Minimi • Action: Extends 5 th digit and hand • Origin: Lateral epicondyle of humerus • Insertion: Extensor expansion of the fifth digit 13 Posterior, Middle Layer

Extensor Carpi Ulnaris • Action: Extends and adducts hand • Origin: Lateral epicondyle of humerus; posterior surface of ulna • Insertion: Metacarpal of the fifth digit 14 Posterior, Superficial Layer

Anconeus • Action: Very weak extension of the forearm • Origin: Lateral epicondyle of humerus • Insertion: Olecranon process of ulna 15

Abductor pollicis longus • Action: Abducts and extends thumb • Origin: posterior surface of ulna and radius • Insertion: first metacarpal 16

Extensor Pollicis Longus • Action: Extends thumb • Origin: Posterior surface of ulna and interosseous membrane • Insertion: Distal phalanx of thumb 17 Posterior, Deepest Layer

Extensor Pollicis Brevis • Action: Extends thumb • Origin: Posterior surface of radius and interosseous membrane • Insertion: Proximal phalanx of thumb 18 Posterior, Deepest Layer

Supinator • Action: Supinates forearm • Origin: Lateral epicondyle of humerus; proximal ulna • Insertion: Posterior, lateral and anterior surfaces of proximal radius 19 Posterior, Deepest Layer

Abductor pollicis brevis • Action: Abducts thumb and aids in flexion • Origin: scaphoid and trapezium • Insertion: Proximal phalanx of thumb 20

Flexor pollicis brevis • Action- flexes thumb • Origin- Trapezium • Insertion: Proximal phalanx of thumb 21

Flexor digiti minimi • Action: Flexes fifth digit • Origin: hook of hamate • Insertion: proximal phalanx of fifth digit 22

Abductor digiti minimi • Action: Abducts fifth digit • Origin: Pisiform and tendon of flexor carpi ulnaris • Insertion: Proximal phalanx of fifth digit 23

MUSCLES OF DEEP BACK AND GLUTEAL REGION

Gluteus Maximus • Action: Principal extensor and lateral rotator of femur • Origin: Lateral surface of ilium; dorsal surface of scrum and coccyx • Insertion: iliotibial tract; gluteal tuberosity of femur 25

Gluteus Medius • Action: Abduction and medial rotation of femur • Origin: Lateral surface of ilium • Insertion: Greater trochanter of femur, lateral surface 26

Piriformis • Action- laterally rotates thigh at hip joint, abducts thigh • Origin: Anterior surface of sacrum • Insertion: Greater trochanter of femur superior surface 27

Quadratus Femoris • Action: Rotates thigh laterally • Origin: Ischial tuberosity • Insertion: Greater trochanter of femur 28

Psoas Major • Action: flexion of the thigh • Origin: Transverse processes of bodies of lumbar vertebrae • Insertion: Lesser trochanter of femur with iliacus 29

Iliacus • Action: Flexes thigh and laterally rotates femur • Origin: Iliac fossa and lateral margin of scrum • Insertion: Lesser trochanter of femur with psoas major 30

ANTERIOR COMPARTMENT OF THE THIGH

Sartorius • Action: Flexes both femur and tibia • Origin: Anterior superior iliac spine • Insertion: Medial margin of tibial tuberosity 32

Rectus Femoris • Action: Extends tibia and flexes femur • Origin: Anterior inferior iliac spine and upper margin of acetabulum • Insertion: Tibial tuberosity 33

Vastus Lateralis • Action: Extension of leg • Origin: Intertrochanteric line and linea aspera of femur • Insertion: Tibial tuberosity 34

Vastus Medialis • Action: Extends tibia • Origin: Intertrochanteric line and linea aspera of femur • Insertion: Tibial tuberosity • 35

Vastus Intermedius • Action: Extends tibia • Origin: Upper shaft of femur • Insertion: Tibial tuberosity 36

Tensor Fasciae Latae • Action: Flexes thigh, stabilizes knee • Origin: Iliac crest • Insertion: iliotibial tract 37

Medial thigh muscles

Pectineus • Action: Adduction and flexion of thigh • Origin: Superior ramus of pubis • Insertion: Just inferior to the lesser trochanter 39

Adductor Longus • Action: Adducts, flexes & medially rotates femur • Origin: Between pubic rami near symphysis • Insertion: Middle third of linea aspera 40

Adductor Magnus • Action: adduction and flexion of thigh • Origin: Pubic arch and ischial tuberosity • Insertion: Linea aspera and adductor tubercle 41

Gracilis • Action: Adducts, flexes, medially rotates tibia • Origin: Inferior pubis near symphysis • Insertion: Upper portion of tibia 42

Posterior thigh muscles

Semitendinosus • Action: Extends femur and flexes leg • Origin: Ischial tuberosity • Insertion: Medial condyle of tibia 44

Semimembranosus • Action: Extends femur and flexes leg • Origin: Ischial tuberosity • Insertion: Medial condyle of tibia • 45

Biceps Femoris • Action: Extends femur and flexes leg • Origin: Long headischial tuberosity • Short head- lateral supracondylar ridge of femur • Insertion: Head of fibula and lateral condyle of tibia Long Head Short Head 46

ANTERIOR COMPARTMENT OF THE LEG

Tibialis Anterior • Action: Dorsiflexes and inverts foot • Origin: Upper half of tibia and interosseous membrane • Insertion: Base of first cuneiform and first metatarsal 48

Extensor Digitorum Longus Tendon • Action: Dorsiflexes foot and extends toes • Origin: Tibia, proximal ¾ of fibula & interosseous membrane • Insertion: Tendons of middle & terminal phalanges of 4 lateral toes by extensor expansion 49

Extensor Hallucis Longus • Action: Dorsiflexes foot and extends great toe • Origin: Middle half of fibula and interosseous membrane • Insertion: Distal phalanx of great toe Tendon 50

LATERAL COMPARTMENT OF THE LEG

Fibularis Longus • Action: Plantar flexes and eversion of foot • Origin: Upper 2/3 rds of fibula and intermuscular septa • Insertion: Plantar base of first metatarsal and first cuneiform 52

Fibularis Brevis • Action: Eversion of foot • Origin: Lateral surface of fibula • Insertion: Fifth metatarsal 53

Extensor Digitorum brevis • Action: Extends toes • Origin: Dorsal surface of calcaneus • Insertion: four tendons into extensor expansion 54

Extensor hallucis brevis • Action: Extends big toe • Origin: Medial surface of calcaneus • Insertion: proximal phalanx of great toe 55

POSTERIOR COMPARTMENT OF THE THIGH

Superficial Group

Gastrocnemius • Action: plantar flexion of foot; flexion of the leg • Origin: Lateral head: lateral condyle of femur • Medial head: popliteal surface of femur • Insertion: Calcaneus Superficial 58

Soleus • Action: Plantar flexion of foot; • Origin: Head of fibula; posterior surface of fibula; medial aspect of tibia • Insertion: Calcaneus by the calcaneal (Achilles) tendon Second Layer 59

Plantaris • Action: Assists in plantar flexion of foot and flexion of leg • Origin: Lateral supracondylar line of femur • Insertion: Calcaneus Second Layer 60

Deep group

Popliteus • Action: Flexes and unlocks knee joint • Origin: Lateral condyle of femur; lateral meniscus in knee joint • Insertion: Posterior surface of tibia Second Layer 62

Flexor Digitorum Longus • Action: plantar flexion of foot; flexion of toes • Origin: Posterior surface of tibia • Insertion: Distal phalanges of digits 2 -5 Third Layer 63

Flexor Hallucis Longus • Action: plantar flexion of foot; flexion of great toe • Origin: Posterior surface of fibula; interosseous membrane • Insertion: Distal phalanx of great toe Third Layer 64

Tibialis Posterior • Action: Plantar flexion and inversion of foot • Origin: Posterior surfaces of tibia and fibula; interosseous membrane • Insertion: Navicular, cuboid, and cuneiform bones; second third and fourth metatarsals Third Layer 65

Abductor hallucis • Action: Abducts and flexes great toe • Origin: Calcaneus and plantar aponeurosis • Insertion: Proximal phalanx of great toe 66

Flexor digitorum brevis • Action: Flexes lateral four toes • Origin: Tuberosity of calcaneus • Insertion: Middle phalanges of digits 2 -5 67

Abductor digiti minimi • Action: Abducts 5 th toe • Origin: tuberosity of calcaneus • Insertion: by four tendons into middle phalanx of lateral four toes 68

Flexor hallucis brevis • Action: Flexes big toe • Origin: Cuboid and lateral cuneiform bones • Insertion: Proximal phalanx of great toe 69

Flexor digiti minimi brevis • Action: Flexes small toe • Origin: Base of 5 th metatarsal • Insertion: Base of proximal 5 th phalanx 70

The End 71