Types Of Muscles

Front 1

Trapezius

Back 1

Origin: 1. Occipital bone 2. Vertebrae (cervical and thoracic)
Insertion: 1. Clavicle 2. Scapula (spine and coracoid)
Function: 1. Raises or lowers shoulders and shrugs them. 2. Extends head when occiput acts as insertion
Innervation: Spinal accessory, 2nd 3rd 4th cervical nerves

Front 2

Serratus anterior

Back 2

Origin: Ribs (Upper 8 or 9)
Insertion: Scapula (anterior surface, vertebral border)
Function: Pulls shoulder forward, abducts and rotates it upward
Innervation: Long thoracic nerve

Front 3

Pectoralis major

Back 3

Origin: 1. Clavicle (medial half) 2. Sternum 3. Costal cartilages of true ribs
Insertion: Humerus
Function: 1. Flexes upper arm 2. Adducts upper arm anteriorly; draws it across chest.
Innervation: Medial and lateral anterior thoracic nerves

Front 4

Latissimmus dorsi

Back 4

Origin: 1. Vertebrae (spines of lower thoracic, lumbar, and sacra) 2. Ilium (crest) 3. Lumbodorsal fascia
Insertion: Humerus (intertubercular groove)
Function: 1. Extends upper arm 2. Adducts upper arm posteriorly
Innervation: Thoracodorsal nerve

Front 5

Deltiod

Back 5

Origin: 1. Clavicle 2. Scapula (spine and acromion)
Insertion: Humerus (lateral side about half way down deltoid tubercle)
Function: 1. Abducts upper arm 2. Assists in flexion and medial rotation of arm
Innervation: Axillary nerve

Front 6

Biceps brachii

Back 6

Origin: 1. Scapula (supraglenoid tuberosity) 2. Scapula (coracoid)
Insertion: Radius (tubercle at proximal end)
Function: 1. Flexes supinated (turned so that palm or sole is facing up) forearm 2. Supinates forearm and hand
Innervation: Musculotaneous nerve

Front 7

Brachialis

Back 7

Origin: Humerus (distal half, anterior surface)
Insertion: Ulna (front of coranoid process)
Function: Flexes pronated (turned so that it is facing downward or inward) forearm
Innervation: Musculotaneous nerve

Front 8

Triceps brachii

Back 8

Origin: 1. Scapula (infraglenoid tuberosity) 2. Humerus (posterior surface-lateral head above radial groove; medial head, below)
Insertion: Ulna (olecranon process)
Function: Extends lower arm
Innervation: Radial nerve

Front 9

Rectus femoris

Back 9

Origin: Ilium (anterior, inferior spine)
Insertion: Tibia (by way of patellar tendon)
Function: 1. Flexes thigh 2. Extends lower leg
Innervation: Femoral nerve

Front 10

Gluteus maximus

Back 10

Origin: 1. Ilium (crest and posterior surface) 2. Sacrum and coccyx (posterior surface) 3. Sacrotuberous
Insertion: 1. Femur (gluteal tuberosity) 2. Iliotibial tract
Function: Extends thigh-rotates outward
Innervation: Inferior gluteal nerve

Front 11

Gluteus medius

Back 11

Origin: Ilium (lateral surface)
Insertion: Femur (greater trochanter)
Function: Abducts thigh-rotates outward; stabilizes pelvis on femur
Innervation: Superior gluteal nerve

Front 12

Vastus medialis

Back 12

Origin: Femur
Insertion: Tibia (by way of patellar tendon)
Function: Extends leg
Innervation: Femoral nerve

Front 13

Biceps femoris

Back 13

Origin: 1. Ischium (tuberosity) 2. Femur (linea aspera)
Insertion: 1. Fibula (head of) 2. Femur (lateral condyle)
Function: Flexes leg
Innervation: Hamstring nerve (branch of sciatic nerve)

Front 14

Semitendinosus

Back 14

Origin: Ischium (tuberosity)
Insertion: Tibia (proximal end, medial surface)
Function: Extends thigh
Innervation: Hamstring nerve

Front 15

Semimembranosus

Back 15

Origin: Ischium (tuberosity)
Insertion: Tibia (medial condyle)
Function: Extends thigh
Innervation: Hamstring nerve

Front 16

Gastrocnemius

Back 16

Origin: Femur (condyle)
Insertion: Tarsal (calcaneus by way of Achilles tendon)
Function: Extends foot, flexes lower leg
Innervation: Tibial nerve (branch of sciatic nerve)

Front 17

Soleus

Back 17

Origin: 1. Tibia (underneath gastrocnemius) 2. Fibula
Insertion: Tarsal (calcaneus by way of Achilles tendon)
Function: Extends foot (plantar flexion)
Innervation: Tibial nerve

Front 18

Sternocleidomastoid

Back 18

Origin: 1. Sternum 2. Clavicle
Insertion: Temporal bone (mastoid process)
Function: Flexes head (prayer muscle) One muscle alone, rotates head toward opposite side, spasm of this muscle alone or associated with trapezius called torticollis or wryneck

Front 19

External oblique

Back 19

Origin: Ribs (lower 8)
Insertion: 1. Ossa coxae (iliac crest and pubis by way of inguinal ligament) 2. Linea alba by way of an aponeurosis
Function: Compresses abdomen
Innervation: Lower 7 intercostal nerves and iliohypogastric nerves

Front 20

Internal oblique

Back 20

Origin: 1. Ossa coxae (iliac crest and inguinal ligament) 2. Lumbodorsal fascia
Insertion: 1. Ribs (lower 3) 2. Pubic bone 3. Linea alba
Function: Compresses abdomen
Innervation: Last 3 intercostal nerves, iliohypogastric and ilioguinal nerves

Front 21

Rectus abdominis

Back 21

Origin: Ossa coxae (pubic bone and symphysis pubis)
Insertion: 1. Ribs (costal cartilage of 5th 6th and 7th ribs) 2. Sternum (xiphoid process)
Function: Compresses abdomen, flexes trunk
Innervation: Last 6 intercostal nerves

Front 22

Masseter

Back 22

Origin: Zygomatic arch
Insertion: Mandible (external surface)
Function: Closes jaw
Innervation: Cranial nerve V

Front 23

Epicranius (occipitofrontalis)

Back 23

Origin: Occipital bone
Insertion: Tissues of eyebrows
Function: Raises eyebrows, wrinkles forehead horizontally
Innervation: Cranial nerve VII