Anterior Muscles

Question 1

Pectoralis Major

Answer 1

Origin: Clavicular head of clavicle
Sternocostal head - sternum and costal cartilages 2-6
Insert: Greater tubercle of humerus
Action: Prime mover of arm flexion, adduction and medial rotation of arm

Question 2

Deltoid

Answer 2

Origin: Spine and acromion process of scapula, lateral 1/3 of clavicle
Insert: Deltoid tuberosity of humerus
Action: Prime mover of arm abduction, synergist in flexion and extension of arm

Question 3

Coracobrachialis

Answer 3

Origin: Coracoid process of scapula
Insert: Mid-medial shaft of humerus
Action: Arm flexion and adduction

Question 4

Serratus anterior

Answer 4

Origin: ribs 1-8 (or 9)
Insert: vertebral border of scapula (ventral surface)

Question 5

Pectoralis minor

Answer 5

Origin: ribs 3-5 (ventral surface)
Insert: coracoid process of scapula

Question 6

Biceps brachii long head

Answer 6

Origin: supraglenoid tubercle of scapula (descends within intertubercular groove of humerus)
Insert: radial tuberosity
Action: major forearm flexor, supinates forearm, weak flexor of arm

Question 7

Biceps brachii short head

Answer 7

Origin: coracoid process of scapula
Insert: radial tuberosity
Action: major forearm flexor, supinates forearm, weak flexor of arm

Question 8

Brachialis

Answer 8

Origin: anterior, distal surface of humerus
Insert: coronoid process and tuberosity of ulna
Action: Major forearm flexor

Question 9

Brachioradialis

Answer 9

Origin: lateral epicondyle of humerus
Insert: styloid process of radius
Action: forearm flexion

Question 10

Iliacus

Answer 10

Origin: Iliac fossa of the os coxa
Insertion: lesser trochanter of femur
Action: prime flexor of thigh, postural muscle (fibers converge into tendon of psoas major)

Question 11

Psoas major

Answer 11

Origin: Vertebrae T12-L5
Insertion: lesser trochanter of femur
Action: prime flexor of thigh, postural muscle

Question 12

Sartorius

Answer 12

Origin: anterior superior iliac spine
Insertion: medial proximal tibial shaft (near tibial tuberosity)
Action: flexion and lateral rotation of thigh, flexion of lower leg

Question 13

Rectus femoris

Answer 13

Origin: Anterior inferior iliac spine and superior margin of acetabulum
Insertion: patella via quadriceps tendon
Action: thigh flexion, lower leg extension

Question 14

Vastus lateralis

Answer 14

Origin: greater trochanter and linea aspera of femur
Insertion: patella via quadriceps tendon
Action: lower leg extension and stabilizes patella

Question 15

Vastus medialis

Answer 15

Origin: linea aspera of femur
Insertion: patella via quadriceps tendon
Action: lower leg extension and stabilizes patella

Question 16

Vastus intermedius

Answer 16

Origin: proximal anterolateral femoral shaft
Insertion: patella via quadriceps tendon
Action: lower leg extension

Question 17

Tensor fasciae latae

Answer 17

Origin: anterior aspect of iliac crest and anterior superior iliac spine
Insertion: iliotibial tract
Action: abduction and flexion of thigh

Question 18

Pectineus

Answer 18

Origin: pubis of os coxa
Insertion: pectineal line of femur
Action: adduction and flexion of thigh

Question 19

Gracilis

Answer 19

Origin: ramus and body of pubis
Insertion: medial proximal tibial shaft
Action: adducts thigh, flexes and medially rotates leg

Question 20

Adductor longus

Answer 20

Origin: inferior ramus of pubis (anterior to brevis)
Insertion: linea aspera of femur
Action: adduction and medial rotation of thigh (when thigh flexed)

Question 21

Adductor magnus

Answer 21

Origin: ischial and pubic rami and ischial tuberosity
Insertion: linea aspera of femur
Action: extension, adduction, and medial rotation of thigh (when thigh flexed)