Forearm anatomy Flashcards
Name the muscles in the superficial compartment of the anterior forearm.
Flexor carpi ulnaris
Palmaris longus
Flexor carpi radialis
Pronator teres
Where do muscles of the anterior forearm originate from?
The medial epicondyle of the humerus.
Name the muscles in the intermediate compartment of the anterior forearm.
Flexor digitorum superficialis
Name the muscles in the deep compartment of the anterior forearm.
Flexor pollicis longus
Flexor digitorum profundus
Pronator quadrates
What are the actions of the muscles in the anterior forearm?
Pronation of forearm
Flexion of wrist
Flexion of fingers
The anterior compartment of the forearm is also known as what?
The flexor compartment
What nerve provides innervation for most of the muscles in the anterior forearm?
Median nerve
Which muscles in the forearm are not innervated by the median nerve?
Flexor carpi ulnaris
Medial half of flexor digitorum profundus
What is the innervation for the flexor carpi ulnaris and the medial half of the flexor digitorum profundus?
Ulnar nerve
What is the function of the flexor carpi ulnaris?
Flexion and adduction at the wrist.
Innervation of the flexor carpi ulnaris?
Ulnar nerve
What is the function of the palmaris longus?
Wrist flexion
What is the innervation of the palmaris longus?
Median nerve
What is the function of the flexor carpi radialis?
Wrist flexion and abduction.
What is the innervation of the flexor carpi radialis?
Median nerve
What is the function of the pronator Teres?
Pronation of forearm.
What is the innervation of the pronator Teres?
Median nerve.
What is the function of the flexor digitorum superficialis?
Flexes MCP joints
Flexes PIP joints of 4 fingers
Flexes wrist
What is the innervation of the flexor digitorum superficialis?
Median nerve
What are the functions of the flexor digitorum profundus?
Flexes DIP joints
Flexes MCP joints
Flexes wrist
What is the innervation of the flexor digitorum profundus?
Medial half (acts on little and ring fingers) = ulnar nerve.
Lateral half (acts on middle and index fingers) = anterior interosseous branch of median nerve
What is the function of the flexor pollicis longus
Flexes IP and MCP joint of thumb.
What is the innervation of the flexor pollicis longus?
Median nerve (anterior interosseous branch)
What is the function of the pronator quadratus?
Pronation of forearm.
What is the innervation of the pronator quadratus?
Median nerve (anterior interosseous branch)
What are the muscles in the posterior compartment of the forearm known as?
Extensor muscles.
Which nerve innervates the posterior compartment of the forearm?
Radial nerve.
How many muscles are in the superficial layer of the posterior forearm?
7
Name the 7 muscles in the superficial compartment of the posterior forearm.
Brachioradialis
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor digitorum
Extensor digiti minimi
Extensor carpi ulnaris
Anconeus
How many muscles are there in the deep compartment of the posterior forearm?
5
Name the 5 muscles in the deep compartment of the posterior forearm.
Supinator
Abductor pollicis longus
Extensor pollicis longus
Extensor policis brevis
Extensor indices
What is the function of the brachioradialis muscle?
Elbow flexion.
What is the innervation of the brachioradialis muscle?
Radial nerve.
What are the functions of the extensor carpi radialis longus and brevis?
Abduction and flexion at the wrist.
What is the innervation of the extensor carpi radialis longus and brevis?
Radial nerve.
What is the function of the extensor digitorum?
Extension of fingers at IP and MCP joints.
What is the innervation of the extensor digitorum?
Deep branch of radial nerve.
What is the function of the extensor digit minimi?
Extends little finger (contributes to wrist extension)
What is the innervation of the extensor digit minimi?
Deep branch of radial nerve.
What is the function of the extensor carpi ulnaris?
Extension and adduction of the wrist.
What is the innervation of the extensor carpi ulnaris?
Deep branch of radial nerve.
What is the function of the anconeus?
Extends and stabilises elbow joint.
Abducts ulna during pronation of forearm.
What is the innervation of the anconeus?
Radial nerve.
What causes tennis elbow?
Repeated use of the superficial extensor muscles of the forearm.
What do the deep posterior forearm muscles act on?
The thumb and index finger (aside from supinator).
Which deep muscles of the posterior forearm does not act on the thumb or index finger?
Supinator.
What is the function of the abductor pollicis longus?
Abduction of the thumb.
What is the innervation of the abductor pollicis longus?
Posterior interosseous branch of the radial nerve.
What is the function of the extensor pollicis brevis?
Extends MCP and CMC joints of the thumb.
What is the innervation of the extensor pollicis brevis?
Posterior interosseous branch of the radial nerve.
What is the function of the extensor pollicis longus?
Extends all joints of the thumb (CMC, MCP and IP joints).
What is the innervation of the extensor pollicis longus?
Posterior interosseous branch of the radial nerve.
What is the function of the extensor indicis?
Extends index finger.
What is the innervation of the extensor indicis?
Posterior interosseous branch of the radial nerve.
What is wrist drop a sign of?
Radial nerve injury
At what 2 sites is the radial nerve commonly injured at?
Axilla - humeral dislocations or fractures of proximal humerus.
Radial groovy of humerus - humeral shaft fracture.
Which branch of the radial nerve supplies the extensor carpi radialis brevis?
Deep branch
The deep branch of the radial nerve supplies which forearm muscles?
Extensor carpi radialis brevis
Supinator
The radial nerve innervates which posterior forearm muscles before it branches off?
Extensor carpi radialis longus
Brachioradialis
What is the common origin of the lumbricals?
Flexor digitorum profundus
