Muscle origins and insertions

Each of the 29 muscles in the origin and insertion explorer has a page of its own: every attachment and the bone it is on, the muscle’s actions and its nerve, as Gray’s Anatomy (1918) describes them, and for 18 of them the lifts that use them as a prime mover or synergist.

What is the difference between a muscle’s origin and its insertion?

The origin is the attachment that usually stays fixed, often the end nearer the trunk, and the insertion the one that moves. Contraction pulls the insertion towards the origin, and the roles swap when the far end is the fixed one, as for latissimus dorsi in a pull-up, which pulls the trunk up to the arm.

Every muscle, by group

Rotator cuff

• Supraspinatus From the scapula to the humerus.
• Infraspinatus From the scapula to the humerus.
• Teres minor From the scapula to the humerus.
• Subscapularis From the scapula to the humerus.

Deltoid and teres major

• Deltoid From the clavicle and scapula to the humerus.
• Teres major From the scapula to the humerus.

Shoulder girdle

• Pectoralis major From the clavicle, manubrium, body of sternum and second to sixth costal cartilages to the humerus.
• Pectoralis minor From the third to fifth ribs to the scapula.
• Serratus anterior From the first to eighth ribs to the scapula.
• Subclavius From the first rib to the clavicle.
• Trapezius From the occipital bone, seventh cervical vertebra and first to twelfth thoracic vertebrae to the clavicle and scapula.
• Levator scapulae From the atlas, axis, and third and fourth cervical vertebrae to the scapula.
• Rhomboid minor From the seventh cervical vertebra and first thoracic vertebra to the scapula.
• Rhomboid major From the second to fifth thoracic vertebrae to the scapula.

Arm flexors

• Biceps brachii From the scapula to the radius.
• Coracobrachialis From the scapula to the humerus.
• Brachialis From the humerus to the ulna.
• Brachioradialis From the humerus to the radius.

Arm extensors

• Latissimus dorsi From the seventh to twelfth thoracic vertebrae, hip bone and tenth to twelfth ribs to the humerus.
• Triceps brachii From the scapula and humerus to the ulna.
• Anconeus From the humerus to the ulna.

Forearm rotators

• Supinator From the humerus and ulna to the radius.
• Pronator teres From the humerus and ulna to the radius.
• Pronator quadratus From the ulna to the radius.

Muscles of mastication

• Masseter From the zygomatic bone and temporal bone to the mandible.
• Temporalis From the temporal bone, parietal bone, frontal bone and sphenoid bone to the mandible.
• Medial pterygoid From the sphenoid bone, palatine bone and maxilla to the mandible.
• Lateral pterygoid From the sphenoid bone to the mandible.

Neck

• Sternocleidomastoid From the manubrium and clavicle to the temporal bone and occipital bone.

Muscles by nerve

Every nerve the records name, with the muscles here it supplies, in the order the groups above list them.

Sources

• Gray (1918), Myology, the muscles and fasciae of the shoulder
• Gray (1918), Myology, the muscles connecting the upper extremity to the anterior and lateral thoracic walls
• Gray (1918), Myology, the muscles connecting the upper extremity to the vertebral column
• Gray (1918), Myology, the muscles and fasciae of the arm
• Gray (1918), Myology, the muscles and fasciae of the forearm
• Gray (1918), Myology, the muscles of mastication
• Gray (1918), Myology, the lateral cervical muscles

Every attachment, action and nerve is as Gray’s Anatomy (1918) describes it, in modern terms. The lift roles are from muscles worked by exercise, where each lift names the sources it follows.

The values are facts and free to use; this page’s selection and presentation are © 2026 ScienceQuest.

See these muscles in 3D

Visualiser · Biology Muscle Origin, Insertion and Action Explorer Paint a muscle’s origin and insertion on real 3D bones, or click a bone to see what attaches to it. Visualiser · Biology Muscles Worked by Exercise 3D Explorer Choose a lift and a real body lights its prime movers, synergists and stabilisers, front and back, with the same muscles in 3D.