Muscle Chart: Functions, Origins, and Insertions

Sternocleidomastoid

Flexion of the head and rotates the neck and head. Origin is the tissue covering the pectoral and deltoid muscle. Insertion is the tissue around the mouth.

Rectus Femoris

A part of the quadriceps femoris. Extends the knee and flexes the hip. Origin is the anterior iliac spine and acetabulum. Insertion is the patella and tibial tuberosity.

Vastus Medialis

A part of the quadriceps femoris. Extends the knee. Its origin is the shaft of the femur. Its insertion is the patella and tibial tuberosity.

Vastus Lateralis

A part of the quadriceps femoris. It extends the knee. Its origin is the trochanter of the femur and its insertion is the patella and tibial tuberosity.

Vastus Intermedius

A part of the quadriceps femoris. Origin is the shaft of the femur (different place the other quadriceps femoris muscle of the same origin). Insertion is the patella and tibial tuberosity

Gluteus Medius

Abducts and rotates the hip. Origin is the lateral surface of ilium. Its insertion is the trochanter of the femur.

Adductor Muscle Group

Adducts and rotates the hips. Its origin is the inferior portion of Pelvis (ischium and pubis). Its insertion is along the medial shaft of the femur.

Buccinator

Allows whistling, sucking, and compression of the cheeks inward. Origin is the maxilla and the mandible near the molars. Insertion is the tissue around the mouth.

Orbicularis Oculi

Blinks and closes the eyes. Its origin is the frontal bone (superiorly) and the maxillary bone (Inferiorly) and its insertion is the tissue around the eyes.

Orbicularis Oris

Closes and puckers the lips. Origin is the maxilla (superiorly) and the mandible (inferiorly). Insertion is the tissue around the lips.

Temporalis

Closes the jaw (mastication) and wiggles the ears. Origin is the temporal bone and the insertion is the mandible.

Masseter

Closes the jaw (mastication). Its origin is the zygomatic process and its insertion is the ramus of the mandible.

Transverse Abdominis

Compresses abdominal contents. Origin is the lower ribs, iliac crest, and lumbar fascia. The insertion is the broad anterior aponeurosis. (which extends from the xiphoid process to the pubic bone)

Tibialis Anterior

Dorsiflexes and inverts foot. Its origin is the lateral condyle of the tibia. Its insertion is the first metatarsal.

External Intercostals

Elevates and depresses the ribcage during inspiration and expiration. The origin is the rib above it while the insertion is the rib below it.

Internal Intercostals

Elevates and depresses the ribcage during inspiration and expiration. The origin is the rib below it while the insertion is the rib above it.

Erector Spinae

Extends the back (at waist) and bends it side to side (called lateral flexion). Its origin is the iliac crest, the ribs, and the processes of the lower vertebrae. Its insertion is the ribs, thoracic and cervical vertebrae, as well as the occipital bone.

Group of Posterior Extensor Muscles

Extends the hand and fingers. Some abduct or adduct the hand. The origin is the distal end of the humerus (lateral tip) while the insertion is the carpals, metacarpals, or phalanges.

Gluteus Maximus

Extends the hip. Its origin is the sacrum and the coccyx. Its insertion is the proximal femur. (via iliotibial tract)

Latissimus Dorsi

Extends, adducts, and medially rotates the arm. Origin is the iliac crest as well as the spinous process of lower thoracic vertebrae and all lumbar vertebrae . Its insertion is the intertubercular groove of the humerus.

Internal Oblique

Flexes and rotates the vertebral column. Origin is the iliac crest and lumbar fascia. Insertion is the lower ribs, and broad anterior aponeurosis.

External Oblique

Flexes and rotates vertebra column. THe origin is the lower ribs. Insertion is the anterior iliac crest and broad anterior aponeurosis

Biceps brachii

Flexes and supinates the forearm. Is a weak arm flexor as well. Its origin is the coracoid process of the scapula and the lip of the glenoid cavity. The insertion is the radius near the head.

Brachialis

Flexes the forearm and is deep to the biceps. Origin is the shaft of the humerus. Insertion is the coronoid process of the ulna.

Group of Anterior Flexor Muscles

Flexes the hand and fingers. Some of these muscles abduct or adduct the hand. Origin is the distal end of the humerus (medial tip) while the insertion is the carpals, metacarpals, or phalanges.

Iliopsoas

Flexes the hip. Origin is the ilium and lumbar vertebrae. Insertion is the trochanter of the femur.

Hamstring Muscle Group

Flexes the knee and extends the hip. The origin is the ischial tuberosity. The insertion is the condyles of the tibia and head of the fibula.

Rectus Abdominis

Flexes vertebral column. Origin is the pubic bone (enclosed in aponeurosis). Insertion is the xiphoid process and its surrounding ribs.

Sartorius

Flexes, abducts, and rotates the hip. Origin is the anterior iliac spine. Insertion is the tibia (near medial condyle).

Pectoralis Major

Flexes, adducts, and medially rotates the arm. Its origin is the clavicle, body of the sternum, and the upper ribs. Its insertion is the tubercle of humerus.

Triceps Brachii

Forearm extension and a weak stabilizer of the shoulder joint. Its origin is the lip of the glenoid cavity and the posterior shaft of the humerus. The insertion is the olecranon process of the ulna.

Deltoid

Functions in the abduction of the arm. Origin is the clavicle (anteriorly) and the spine of the scapula (posteriorly). The insertion is the middle of the humerus.

Diaphragm

Is involved in inspiration by flattening on contraction and increasing thoracic volume. Origin is the xiphoid process, lower ribs, and lumbar vertebrae. Insertion is the central tendon of the diaphragm.

Platysma

Lowers the jaw, tenses the neck, and helps with facial expression

Gastrocnemius

Plantar flexes the foot and flexes the knee. Origin is the medial and lateral condyles of the femur. The insertion is the calcaneus via calcaneal tendon.

Soleus

Plantar flexes the foot. It is deep to the gastrocnemius. Origin is the proximal tibia and fibula. Insertion is the calcaneus (via calcaneal tendon)

Fibularis Longus

Plantar flexion and everts the foot. Its origin is the head of the fibula and its insertion is the first metatarsal (underneath the foot).

Occipitalis

Responsible for moving the scalp. Its origin is the occipital bone and it inserts into the cranial aponeurosis

Frontalis

Responsible for raising the eyebrows. Its origin is the cranial aponeurosis and its insertion is the tissue of the eye.

Trapezius

Stabilizes and elevates the scapula. Its origin is the occipital bone and the spinous processes of cervical and thoracic vertebrae. The insertion is the spine of the scapula and the clavicle.

Brachioradialis

Syngergist in forearm flexion. The origin is the distal end of the humerus while the insertion is the styloid process of the radius.