Forearm Flashcards
Where do the superficial veins lie within the forearm?
Within the subcutaneous fat
What is the common origin of the flexor muscles of the forearm?
Medial epicondyle
How many layers of muscles are there within the anterior compartment, what are they?
1) Superficial
2) Intermediate
3) Deep
What are the superficial muscles of the anterior compartment of the forearm?
Medial to lateral
1) Flexor carpi ulnaris
2) Palmaris longus
3) Flexor carpi radialis
4) Pronator teres
What shape is the pronator teres muscle?
Cyclindrical
What characterises the palmaris longus muscle?
Small muscle with very long tendon
Which muscle makes up the intermediate layer of the anterior compartment?
Flexor digitorum superficialis
How many tendons does flexor digitorum superficialis split into and where do they pass?
Splits into 4 tendons, they pass through the carpal tunnel
What lies on the underside of flexor digitorum superficialis?
Median nerve
Which muscle lies deep to flexor digitorum superficialis?
Flexor digitorum profundus
Which muscles make up the deep layer of the anterior compartment?
Flexor digitorum profundus
Flexor pollicis longus
Pronator quadratus
How many tendons does flexor digitorum profundus split into and where do they pass?
Splits into 4 tendons, pass through the carpal tunnel
Which muscle lies in the deep layer of the anterior compartment lateral to flexor digitorum profundus?
Flexor pollicis longus
Which muscle lies deepest in the deep layer of the anterior compartment of the forearm and where does it run from and to?
Pronator quadratus, can be viewed by separating flexor digitorum profundus and flexor pollicis longus, runs from radius to ulnar
What is the common origin of the extensor muscles of the forearm?
The lateral epicondyle
Which muscle is most lateral/radial in the superficial layer of the posterior compartment of the forearm?
Brachioradialis
What is unusual about brachioradialis muscle?
So far to the radial side that its almost in the anterior compartment
Considered part of the posterior/extensor compartment but it acts as a flexor of the arm
How many layers of muscles make up the posterior compartment of the forearm what are they called?
1) Superficial layer
2) Deep layer
Which muscle lies medial to brachioradialis in the posterior compartment of the forearm?
Extensor carpi radialis longus
From lateral to medial which muscles make up the superficial layer of the posterior compartment of the forearm?
1) Brachioradialis
2) Extensor carpi radialis longus
3) Extensor carpi radialis brevis
4) Extensor digitorum (lies in the midline)
5) Extensor digiti minimi
6) Extensor carpi ulnaris
How many tendons does extensor digitorum split into where do they pass?
Splits into 4 tendons which pass deep to the extensor retinaculum
Which 4 muscles make up the deep layer of the posterior compartment of the forearm from medial to lateral?
1) Extensor indicis
2) Extensor pollicis longus
3) Extensor pollicis brevis
4) Abductor pollicis longus
Abductor pollicis longus muscle wraps around what?
The radius
Which tendons form the medial and lateral boundaries of the anatomical snuff box?
Medial boundary - Tendon of extensor pollicis longus
Lateral boundary - tendons of extensor pollicis brevis and abductor pollicis longus
Why is the anatomical snuff box important clinically?
Running along the floor of it is the radial artery so its a pulse point
Its also an area to palpate the carpal bones in suspected fractures
What is the role of supinator muscle and what compartment is it found in?
Found in the deep layer of extensor compartment
Wraps around the radius, works together with biceps brachii to supinate the forearm
What is the cubital fossa?
Triangular shaped area anterior to the elbow
What are the boundaries of the cubital fossa?
Lateral = brachioradialis Medial = pronator teres Superiorly = imaginary line between the 2 epicondyles of the humerus
What muscle forms the floor of the cubital fossa?
Brachialis