Forearm Muscles Anatomy

Forearm Muscles

Pronator Teres

• Origin: Medial epicondyle of the humerus
• Insertion: Lateral radius
• Action: Pronation of the forearm
• Nerve supply: Median nerve

Flexor Carpi Radialis

• Origin: Medial epicondyle of the humerus
• Insertion: Base of the 2nd metacarpal bone
• Action: Flexion and radial deviation of the wrist
• Nerve supply: Median nerve

Flexor Carpi Ulnaris

• Origin: Medial epicondyle of the humerus and medial aspect of the ulna
• Insertion: Pisiform bone, hook of the hamate, and base of the 5th metacarpal bone
• Action: Flexion and ulnar deviation of the wrist
• Nerve supply: Ulnar nerve

Flexor Digitorum Profundus

• Origin: Anterior and medial aspects of the ulna and interosseous membrane
• Insertion: Bases of the distal phalanges of the fingers
• Action: Flexion of the fingers
• Nerve supply: Ulnar and anterior interosseous nerves

Flexor Digitorum Superficialis

• Origin: Medial epicondyle of the humerus
• Insertion: Middle phalanges of the fingers
• Action: Flexion of the fingers
• Nerve supply: Median nerve

Palmaris Longus

• Origin: Medial epicondyle of the humerus
• Insertion: Palmar aponeurosis and flexor retinaculum
• Action: Flexion of the wrist and tenses the palmar aponeurosis
• Nerve supply: Median nerve

Flexor Pollicis Longus

• Origin: Anterior aspect of the radius and interosseous membrane
• Insertion: Base of the distal phalanx of the thumb
• Action: Flexion of the thumb
• Nerve supply: Anterior interosseous nerve

Pronator Quadratus

• Origin: Anterior aspect of the ulna
• Insertion: Anterior aspect of the radius
• Action: Pronation of the forearm
• Nerve supply: Anterior interosseous nerve

Forearm Muscles

Muscles Acting on the Forearm

• Pronation of the forearm is performed by Pronator Teres and Pronator Quadratus muscles

Muscles Acting on the Wrist

• Flexion and radial deviation of the wrist is performed by Flexor Carpi Radialis muscle
• Flexion and ulnar deviation of the wrist is performed by Flexor Carpi Ulnaris muscle
• Palmaris Longus muscle flexes the wrist and tenses the palmar aponeurosis

Muscles Acting on the Fingers

• Flexion of the fingers is performed by Flexor Digitorum Profundus and Flexor Digitorum Superficialis muscles
• Flexor Digitorum Profundus muscle inserts into the bases of the distal phalanges of the fingers
• Flexor Digitorum Superficialis muscle inserts into the middle phalanges of the fingers

Muscles Acting on the Thumb

• Flexion of the thumb is performed by Flexor Pollicis Longus muscle
• Flexor Pollicis Longus muscle inserts into the base of the distal phalanx of the thumb

Nerve Supply

• Median nerve supplies Pronator Teres, Flexor Carpi Radialis, Flexor Digitorum Superficialis, and Palmaris Longus muscles
• Ulnar nerve supplies Flexor Carpi Ulnaris muscle
• Anterior interosseous nerve supplies Flexor Digitorum Profundus and Flexor Pollicis Longus muscles

Learn about the origins, insertions, actions, and nerve supplies of the forearm muscles, including Pronator Teres, Flexor Carpi Radialis, and Flexor Carpi Ulnaris.