9 - Arm, Forearm and Hand II Flashcards
Medial Epicondyle
The more prominent pert of the humorous where the ulna articulates. Located more proximally
Lateral Epicondyle
The lesser prominent end of the humorous where more of the radius articulates. Located more medially.
The Ulna
The ulna is a long bone in the forearm. It lies medially and articulates with the humorous PROXIMALLY and articulates with the radius DISTALLY.
Olecranon
A large projection of bone that extends proximally.
It forms part of trochlear notch.
It can be palpated as the ‘tip’ of the elbow.
The triceps brachii muscle attaches to its superior surface.
Coronoid process
This ridge of bone projects outwards anteriorly, forming part of the trochlear notch.
Trochlear Notch
Formed by the olecranon and coronoid process.
It is wrench shaped.
Articulates with the trochlea of the humerus.
Radial Notch
Located on the lateral surface of the trochlear notch, this area articulates with the head of the radius.
Tuberosity of the Ulna
A roughening immediately distal to the coronoid process. It is where the brachialis muscle attaches.
The Radius
long bone in the forearm, it lies laterally
Head of the radius
A disk-shaped structure in the proximal region of the radius.
Radial Tuberosity
A bony projection, which serves as the place of attachment of the biceps brachii muscle.
What muscles are superficial in the posterior compartment if the forearm?
Brachioradialis
Extensor carpi radialis (longus and brevis)
Extensor digitorum
Extensor digit minimi
Externsor carpi ulnaris
Aconeus
What are the superior muscles of the posterior compartment innervated by?
The Radial Nerve
What muscles are deep in the posterior compartment if the forearm?
Supinator
Abductor pollicis longus
Extensor pollicis longus and brevis
Extensor indicies
What are the thenar muscles?
three short muscles located at the base of the thumb. The muscle bellies produce a bulge, known as the thenar eminence.
Thenar Muscles
Opponens Pollicis - largest (lies under the other 2)
Abductor pollicis
Flexor pollicis
What are the Lumbricals?
The four muscles in the hand, each associated with a finger.
Very crucial to finger movement, linking the extensor tendons to the flexor tendons.
Where does each lumbrical originate?
At a tendon of the flexor digitorum profundus.
They pass dorsally and laterally around each finger, and inserts into the extensor hood.
What innervates the lumbricals?
- The lateral two lumbricals (of the index and middle fingers) are innervated by the median nerve.
- The medial two lumbricals (of the little and ring fingers) are innervated by the ulnar nerve.
The Interossei
- Located between the metacarpal bones of the hand.
- They can be divided into two groups – dorsal and palmar.
- They abduct the fingers
- Innervated by the ulnar nerve
Dorsal intrerossei
- The most superficial of all dorsal muscles.
- There are 4 dorsal interossei
- They abduct the digits.
Palmer interossei
- Located anteriorly on the hand.
- There are three palmar interossei muscles.
Palmaris brevis
A small, thin muscle, found superficially in the subcutaneous tissue of the hypothenar eminence (in the palm).
Adductor Pollicis
- The adductor pollicis large triangular muscle with two heads.
- The radial artery passes anteriorly through the space between the two heads, forming the deep palmar arch.
