Anterior Forearm Flashcards
What are the muscles in the superficial compartment?
- flexor carpi lunaris
- palmaris longus
- flexor carpi radialis
- pronator teres
What are the muscles in the intermediate compartment?
The flexor digitorum superficialis is the only muscle of the intermediate compartment.
The muscle is a good anatomical landmark in the forearm – the median nerve and ulnar artery pass between its two heads, and then travel posteriorly.
What are the muscles in the deep compartment?
- flexor digitorum profundus
- flexor pollicis longus
- pronator quadratus.
Give the attachments, actions and innervation flexor carpi lunaris
Attachments: Originates from the medial epicondyle with the other superficial flexors. It also has a long origin from the ulna. It passes into the wrist, and attaches to the pisiform carpal bone.
Actions: Flexion and adduction at the wrist.
Innervation: Ulnar nerve.
Give the attachments, innervation and action of palmaris longus
This muscle is absent in about 15% of the population.
Attachments: Originates from the medial epicondyle, attaches to the flexor retinaculum of the wrist.
Actions: Flexion at the wrist.
Innervation: Median nerve.
Give the attachments, innervation and actions of flexor carpi radialis
Attachments: Originates from the medial epicondyle, attaches to the base of metacarpals II and III.
Actions: Flexion and abduction at the wrist.
Innervation: Median nerve.
Give the attachment, action and innervation of pronator teres
Attachments: It has two origins, one from the medial epicondyle, and the other from the coronoid process of the ulna. It attaches laterally to the mid-shaft of the radius.
Actions: Pronation of the forearm.
Innervation: Median nerve.
Give the attachments, innervation and actions of flexor digitorum superficialis
The muscle is a good anatomical landmark in the forearm – the median nerve and ulnar artery pass between its two heads, and then travel posteriorly.
Attachments: It has two heads – one originates from the medial epicondyle of the humerus, the other from the radius. The muscle splits into four tendons at the wrist, which travel through the carpal tunnel, and attaches to the middle phalanges of the four fingers.
Actions: Flexes the metacarpophalangeal joints and proximal interphalangeal joints at the 4 fingers, and flexes at the wrist.
Innervation: Median nerve.
Give the attachments, innervation and origins of flexor digitorum profundus
Attachments: Originates from the ulna and associated interosseous membrane. At the wrist, it splits into four tendons, that pass through the carpal tunnel and attach to the distal phalanges of the four fingers.
Actions: It is the only muscle that can flex the distal interphalangeal joints of the fingers. It also flexes at metacarpophalangeal joints and at the wrist.
Innervation: The medial half (acts on the little and ring fingers) is innervated by the ulnar nerve. The lateral half (acts on the middle and index fingers) is innervated by the anterior interosseous branch of the median nerve.
Give the attachments, innervation and actions of flexor pollicis longus
Attachments: Originates from the anterior surface of the radius, and surrounding interosseous membrane. Attaches to the base of the distal phalanx of the thumb.
Actions: Flexes the interphalangeal joint and metacarpophalangeal joint of the thumb.
Innervation: Median nerve (anterior interosseous branch).
Give the attachments, innervation and actions of pronator quadratus.
A square shaped muscle, found deep to the tendons of the FDP and FPL.
Attachments: Originates from the anterior surface of the ulna, and attaches to the anterior surface of the radius.
Actions: Pronates the forearm.
Innervation: Median nerve (anterior interosseous branch).
