Muscle Origin Insertion and Function

Sternocleidomastoid (Origin, insertion, function)

Origin: Sternum, clavicle

Insertion: Mastoid Process

Function: Flexes head side to side, rotates

Splenius (Origin, insertion, function)

Origin: Lower 4 cervical, upper thoracic vertebrae

Insertion: Nuchal line

Function: Rotates head

Erector spinae group (3 muscles, Function)

Comprises Spinalis, Longissimus, and iliocostalis.

Function: Extends and laterally flex spine, and head (longissimus).

Intercostals (Function)

Elevate and Depress ribs during breathing.

Rectus abdominis (Origin, insertion, function)

Origin: Pubic crest

Insertion: Xiphoid process, and inferior ribs

Function: Flexes trunk

External oblique (Function)

Flex and rotate core (vertebral column)

Quadratus lumborum (Origin, insertion, function)

Origin: Iliac crest, lower lumbar vertebrae

Insertion: 12th rib, upper lumbar vertebrae

Function: Extends and laterally flexes/ bend lower vertebral column.

Pectoralis major (Origin, insertion, function)

Origin: Clavicle, sternum

Insertion: Bicipital groove

Function: Flex, adduct, and internally rotate shoulder

Latissimus dorsi (Origin, insertion, function)

Origin: Lower vertebrae, iliac crest, sacrum

Insertion: Bicipital groove

Function: Adducts and extends arm (shoulder)

Rotator cuff (4 muscles, difference in origin, insertion, and function)

(Supraspinatus)
Origin: Supraspinous fossa

insertion: Greater tubercle of Humerus (common tendon)

Function: Stabilise and externally rotate shoulder

(Infraspinatus)
Origin: infraspinous fossa

Insertion: same

Function: same

(Teres Minor)
Origin: Lateral border of scapula (below infraspinatus)

Insertion: same

Function: same

(Subscapularis)
Origin: Subscapular fossa

Insertion: Lesser tubercle

Function: Stabilize and medially roates shoulder

Trapezius (Origin, insertion, function)

Origin: Nuchal line, all cervical and thoracic vertebra

Insertion: Spine of scapula, acromion and clavicle

Function: Elevation, depression, and retraction of scapula (shoulder)

Rhomboids (major and minor) (Origin, insertion, function)

Origin: Spinal column

Insertion: Medial border of scapula

Function: Retract scapula

Levator scapulae (Origin, insertion, function)

Origin: Upper cervical vertebrae

Insertion: Upper, medial border of scapula

Function: Elevates scapula

Serratus anterior (Origin, insertion, function)

Origin: Upper 8-9 ribs

Insertion: Anterior surface of the medial border of scapula

Function: Protracts scapula

Deltoid (Origin, insertion, function)

Origin: Clavicle, acromion, and spine of scapula

Insertion: Deltoid tuberosity

Function: Abducts arm (lateral head)

Coracobrachialis (Origin, insertion, function)

Origin: Coracoid process

Insertion: Medial aspect (part) of humerus

Function: Flexes arm (at shoulder)

Teres major (not part of the rotator cuff group*)

Origin: Inferior angle of scapula

Insertion: Bicipital groove

Function: Medial border

Biceps brachii (Origin LH and SH, insertion, function)

Origin: Long head --> Supraglenoid tubercle, Short head --> Coracoid process

Insertion: Radial tuberosity

Function: Flexes elbow, supinates forearm

Triceps brachii (Origin, insertion, function)

Origin: Lateral head--> Posterior humerus, Long head--Infraglenoid tubercle, Medial head

Insertion: Olecranon

Function: Extends elbow, and extends the arm at the shoulder (long head).

Brachioradialis (Origin, insertion, function)

Origin: Above lateral epicondyle of humerus

Insertion: Styloid process of radius

Function: Flexes elbow (especially when forearm is pronated)

Pronator teres (Origin, insertion, function)

Origin: Medial epicondyle of humerus

Insertion: Radius

Function: Pronates forearm

Wrist flexors and extensors (Origin, insertion, function)

Origin: Medial epicondyle (Flexors), Lateral epicondyle (Extensors)

Insertion: Metacarpals and phalanges

Function: Flex wrist (Flexors), Extend wrist (Extensors)

Gluteus maximus (Origin, insertion, function)

Origin: Iliac crest and sacrum

Insertion: Greater trochanter

Function: Extends and externally rotates hip

Sartorius (Origin, insertion, function)

Origin: Anterior superior iliac spine

Insertion: Medial tibia

Function: Flexes hip and knee

Iliopsoas (iliacus and psoas major combined) (function)

Function: Hip and trunk flexion

Abductors (Origin, insertion, function)

Origin: Pubis

insertion: Linea aspera (femur)

Function: Adduct leg

Quadriceps group (4 muscles, difference in origin, insertion, and function)

(Rectus femoris)
Origin: anterior inferior iliac spine

Insertion: Patellar ligament into tibial tuberosity

Function: Knee extension and hip flexion

(Vastus lateralis)
Origin: Linea aspera

Insertion: same

Function: Knee extension

(Vastus intermedius)
Origin: Anterior femur

Insertion: same

Function: same

(Vastus medialis)
Origin: Linea aspera - same as lateralis

Insertion: same

Function: same

Hamstrings - Bicep femoris (Origin, insertion, function)

Origin: Long head--> Ischial tuberosity, Short head--> Linea aspera

Insertion: Head of fibula

Function: Flex knee, and extend hip

Hamstrings - (Semitendinosus and semimembranosus) (Origin, insertion, function)

Origin: Ischial tuberosity

Insertion: Tibia (medial condyle)

Function: Flex knee, and extend hip

Peroneals (Fubularis longus, and brevis) (function) (common use)

Function: Evert foot

Common use: to put the foot back in place to avoid an ankle injury such as an ankle sprain.

Tibialis anterior (Origin, insertion, function)

Origin: Anterior tibia

Insertion: Cuneiform and 1st metatarsal

Function: Dorsiflexes foot

Gastrocnemius (Origin, insertion, function)

Origin: Medial and lateral condyles of femur (2 heads of femur)

Insertion: Achilles tendon (attaches to calcaneous)

Function: Plantar flexes foot

Soleus (Origin, insertion, function)

Origin: Upper fibula and tibia

Insertion: Achilles tendon

Function: Plantar flexes foot