Flexors of the Forearm Flashcards
What are the layers of the forearm flexors?
- Superficial layer
- Intermediate layer
- Deep layer
What are the muscles of the superficial layer of the forearm?
Medial –> lateral:
* Flexor carpi ulnaris
* Flexor carpi longus
* Flexor carpi radialis
* Pronator teres
Origin of the flexor carpi radialis
Medial epicondyle of the humerus
Insertion of the flexor carpi radialis
Base of metacarpals 2 and 3
Action of flexor carpi radialis
Flexes and abducts the wrist joint
Nerve supply of the flexor carpi radialis
Median nerve
Origin of the palmaris longus
Medial epicondyle of the humerus
Insertion of palmaris longus
Palmar aponeurosis of the hand
Action of palmaris longus
- Flexion of wrist joint
- Tenses the skin when the hand grips
Nerve supply of palmaris longus
Median nerve
Origins of the flexor carpi ulnaris
- Medial epicondyle
- Olecranon
- Posterior border of ulna
Insertions of the flexor carpi ulnaris
- Pisiform bone
- Hamate
- Base of metacarpal 5
Action of the flexor carpi ulnaris
Flexes and adducts the wrist joint
Nerve supply of flexor carpi ulnaris
Ulnar nerve
Origins of the pronator teres
- Medial epicondyle
- Coranoid process
Insertion of the pronator teres
Lateral surface, mid-shaft of radius
Action of the pronator teres
Pronation
Nerve supply of the pronator teres
Median nerve
What are the muscles of the intermediate layer?
Flexor digitorum superficialis
Origin of flexor digitorum superficialis
- Medial epicondyle of the humerus
- Coronoid process
- Oblique line of the radius
Insertion of the flexor digitorum superficialis
Palmar surface of the middle phalanges of the medial 4 fingers
Action of flexor digitorum superficialis
- Flexes proximal inter-phalangeal joints of the medial 4 fingers
- Flex metacarpo-phalangeal joints of the same fingers and the wrist joint
Nerve supply of flexor digitorum superficialis
Median nerve
What are the muscles of the deep layer?
- Flexor digitorum profundus
- Flexor policis longus
- Pronator quadratus
Origin of flexor digitorum profundus
Upper part of front of ulna
Insertion of flexor digitorum profundus
Palmar surfaces of the distal phalanges (medial 4 fingers)
Insertion of flexor digitorum profundus
Palmar surfaces of the distal phalanges (medial 4 fingers)
Action of flexor digitorum profundus
Flexes distal inter-phalangeal joints, metacarpo-phalangeal joints of the medial 4 fingers and flexes the wrist joint
Nerve supply of flexor digitorum profundus
Lateral ½ by anterior interosseous branch of median nerve
Medial ½ by ulnar nerve
Origin of flexor policis longus
Upper part of anterior surface of radius
Insertion of flexor policis longus
Palmar surface of base of distal phalanx of thumb
Action of flexor policus longus
- Flexes inter-phalangeal joint
- Flexes metacarpo-phalangeal joints of the thumb
Nerve supply of flexor policis longus
Anterior interosseous of median nerve
Diagram of flexor digitorum profundus and flexor digitorum superficialis
Origin of pronator quadratus
Distal anterior surface of ulna
Insertion of pronator quadratus
Distal anterior surface of radius
Action of pronator quadratus
Pronation
Nerve supply of pronator quadratus
Anterior interosseous branch of median nerve
What is the origin of the radial artery?
Originates from the brachial artery at the neck of radius
Describe the course of the radial artery
In proximal and middle forearm: Lies deep to the brachioradialis muscle
In distal forearm: Lies between the tendon of the brachioradialis laterally and the tendon of flexor carpi radialis medially
What is the origin of the ulnar artery?
Originates from the brachial artery at the neck of radius
What is the course of the ulnar artery?
- Leaves the cubital fossa by passing deep to the pronator teres muscle
- Passes through the forearm between flexor carpi ulnaris and flexor digitorum profundus muscles
- Distal forearm, it lies lateral to the ulnar nerve
