Muscles in the Arm

This muscle is a synergist of forearm flexion. Its origin is at the mid-humerus.

• Biceps Brachii

• Triceps Brachii

• Brachialis

• Brachioradialis

This muscle bends the wrist and finger and is located on the LATERAL side of the arm

• Supinator

• Flexor Carpi Ulnaris

• Flexor Carpi Radialis

• Palmaris Longus

This muscle's main action is to turn the palms upward.

• Supinator
• Pronator Teres
• Flexor Carpi Radialis
• Palmaris Longus

This long round muscle's main job is to turn the palm downward

• Supinator
• Pronator Teres
• Pronator Quadratus
• Palmaris Longus

This long muscle's insertion is the palmar aponeurosis.

• Supinator
• Pronator Teres
• Flexor Carpi Radialis
• Palmaris Longus

This muscle, on the MEDIAL side of the forearm decreases the angle between bones

• Supinator

• Pronator Teres

• Flexor Carpi Ulnaris

• Palmaris Longus

This muscle, on the medial side of the forearm increaes the angle between bones

• Extensor Carpi Ulnaris
• Flexor Carpi Ulnaris
• Extensor Digitorum
• Palmaris Longus

This shoulder muscle is the prime mover of arm abbduction.

• Deltoid

• Trapezius

• Latissimus Dorsi

• Biceps Brachii

This muscle with two origins is the prime mover of forearm flexion.

• Biceps Brachii

• Triceps Brachii

• Brachialis

• Brachioradialis

This muscle's main action is to extend the forearm at the elbow.

• Biceps Brachii

• Triceps Brachii

• Brachialis

• Brachioradialis