Interval 8:Forearm, hand Flashcards
What kind of joint in the elbow? What bones make it up?
- Hinge joint, which means it can only flex and extend
- Made up of the humerus, ulna, and radius
What forearm joint is responsible for supination and pronation of the forearm?
-Radioulnar joints (proximal and distal)
What are the 3 separate articulations of the elbow joint?
- humero-ulnar
- humero-radial
- radioulnar
Movement at the elbow joint is restricted to _____________; pronation and supination involve movement between the _____________.
- flexion and extension
- radius and ulna
At the humeroradial joint, the head of the radius articulates with the ___________ of the humerus.
-Capitulum
At the humeroulnar joint, the ________ of the ulnar articulates with the _______ of the humerus.
- Trochlear notch
- trochlea
What kind of joints are the humeroradial and humeroulnar joints?
-hinge joints
At the proximal radioulnar joint, the _____________ of the ulnar articulates with the head of the ________.
- radial notch
- radius
The brachial artery continues from the axillary artery at the ____________ and supplies the anterior and posterior aspects of the arm
-lower border of the teres major tendon
If one were to trace the radial nerve around the midshaft of the humerus, would it be coursing with any arteries?
-Yes; profunda brachial artery
What does the profunda brachial artery supply?
-triceps brachii muscle and contributes to collateral circulation around the elbow
The brachial artery gives rise to what 2 arteries and approximately where does this occur?
- radial and ulnar arteries
- in the cubital fossa
What does the ulnar artery generally supply?
-medial side of forearm and hand
name 3 branches of the ulnar artery relevant to this unit
- common interosseous artery
- superficial arch
- deep branch of the ulnar artery
The common interosseous artery arises from the ulnar artery in the _________. What does it branch into and then supply?
- Cubital fossa
- branches into anterior interosseous artery which supplies deep muscles in the anterior forearm
- Branches into posterior interosseous artery which supplies deep muscles in the posterior forearm
The ____________ is a continuation of the ulnar artery?
-superficial arch
What does the superficial arch form and go on to supply?
- forms the superficial palmar arch in the palm of the hand
- branches into palmar metacarpal arteries which supply the hand and digits
What does the deep branch of the ulnar artery anastomose with?
-medial part of the deep palmar arch
What generally does the radial artery supply?
-lateral side of the forearm and hand
Where does the superficial branch of the radial artery arise?
-from the radial artery at the wrist
What does the superficial branch of the radial artery anastomose with?
-lateral part of the superficial palmar arch
What does the distal part of the radial artery become and supply?
-deep palmar arch that branches into dorsal metacarpal arteries which supply the hand and digits
What is the anatomic snuffbox?
The anatomical snuff box is a triangular deepening on the radial, dorsal aspect of the hand—at the level of the carpal bones, specifically, the scaphoid and trapezium bones forming the floor. The name originates from the use of this surface for placing and then sniffing powdered tobacco, or “snuff.”
Describe the course of the distal part of the radial artery
- courses dorsal to the wrist and crosses the floor of the anatomic snuffbox
- enters deep part of palm after passing between the 2 heads of the first dorsal interosseous muscle
- forms deep palmar arch
The _____________ are superficial veins that arise from a venous network on the dorsal aspect of the hand.
cephalic and basilic veins
Describe the route of the cephalic vein
- arises from the lateral aspect of the venous network
- courses on the anterolateral aspect of the forearm and arm
- passes between deltoid and pectoralis major muscles
- drains into the axillary vein
What vein does the cephalic drain into?
-axillary vein
Describe the route of the basilic vein
- arises from medial aspect of the venous network
- courses on medial aspect of the forearm
- courses with brachial artery in the arm
- joins brachial vein to form the axillary vein
The deep veins of the upper limb course with ___________.
-arteries of the same name
The forearm is divided into what compartments and what structures demarcate this division?
- anterior and posterior compartment
- by the radius and ulna, plus the interosseous membrane
The muscles in the posterior compartment of the forearm are innervated by the __________.
-radial nerve and its branches
Most of the muscles of the posterior compartment of the forearm are _________. For the most part, these muscles all have an origin on or around the ____________. Inflammation of this area of origin is commonly called ________.
- extensors
- lateral epicondyle of the humerus
- tennis elbow
The posterior compartment of the forearm has a superficial and deep layer of muscles. List the 7 superficial muscles
- brachioradialis
- extensor carpi radialis longus
- extensor carpi radialis brevis
- extensor digitorum
- extensor digiti minimi
- extensor carpi ulnaris
- Anconeus
The superificial layer of muscles of the posterior compartment of the forearm are all innervated by what nerve?
-radial nerve
Brachioradialis
-elbow flexion
Extensor carpi radialis longus
-extension and radial deviation of the wrist
Extensor carpi radialis brevis
-extension and radial deviation of the wrist
Extensor digitorum
-extends all joints it crosses, wrist and digits 2-5
Extensor digiti minimi
-primarily extends digit 5, but can also extend wrist
Extensor carpi ulnaris
-extension and ulna deviation of the wrist
Anconeus
-elbow extension
Which muscles of the superficial layer of the posterior compartment of the forearm are innervated by the posterior interosseous branch of the radial nerve?
- extensor carpi radialis brevis
- extensor digitorum
- extensor digiti minimi
- extensor carpi ulnaris
What innervates the deep layer of muscles of the posterior compartment of the forearm?
-radial nerve as well
List the 5 deep muscles of the posterior compartment of the forearm
- supinator
- abductor pollicis longus
- extensor pollicis longus
- extensor pollicis brevis
- extensor indicis
Supinator
-supinates the forearm
Abductor pollicis longus
-abducts thumb at the carpometacarpal joint of the thumb
Extensor pollicis longus
-extension of the metacarpophalangeal, carpometacarpal, and interphalangeal joints of the thumb
Extensor pollicis brevis
-extension of the metacarpophalangeal and carpometacarpal joints of the thumb
Extensor indicis
-contributes to extension of index finger and allows extension of this digit individually
Lateral epicondylitis
- aka tennis elbow
- caused by overuse of extensor muscles that attach to lateral epicondyle
- patient will experience pain over lateral epicondyle
What is the etiology of the pain in lateral epicondylitis?
-microtears of the proximal attachment of the extensor muscles
Muscles of the anterior compartment of the forearm of predominantly innervated by _______ with a small contribution from the ________.
- Median nerve
- Ulnar nerve
Most muscles of the anterior compartment of the forearm take their origin from ________.
-medial epicondyle of the humerus
Name the layers of the posterior and anterior compartment of the forearm
Posterior: superficial and deep
Anterior: superficial, intermediate, and deep
4 muscles of superficial layer of the anterior forearm
- pronator teres
- flexor carpi radialis
- palmaris longus
- flexor carpi ulnaris
Pronator teres
-pronation of forearm
Flexor carpi radialis
-wrist flexion and radial deviation of the hand
palmaris longus
- attaches to superficial palmar fascia and therefore can assist in flexion of the wrist
- may be absent on 1 or both side of some individuals
flexor carpi ulnaris
- wrist flexion and ulnar deviation
- innervated by ulnar nerve
Intermediate group muscle of anterior compartment of forearm
-flexor digitorum superficialis
flexor digitorum superficialis
-flexion at wrist, at metacarpophalangeal and proximal interphalangeal joints
Name the muscles of the deep group of the anterior forearm
- flexor pollicis longus
- flexor digitorum profundus
- pronator quadratus
flexor pollicis longus
-flexion at wrist and at metacarpophalangeal and interphalangeal joints of thumb
flexor digitorum profundus
-flexion of the wrist, metacarpophalangeal, proximal and distal interphalangeal joints of digits 2-5
innervation of flexor digitorum profundus
- lateral half by anterior interosseous branch of median nerve
- medial half by ulnar nerve
pronator quadratus
-pronation
innervation of pronator quadratus
-anterior interosseous branch of median nerve
Golfer’s elbow
-inflammation of attachment of anterior compartment muscles to medial epicondyle of the humerus
The median nerve courses medial to the tendon of the biceps and the brachial artery in the arm. It reaches the forearm after passing _______ to the elbow and _____ to the bicipital aponeurosis.
- anterior
- deep
In the forearm, the median nerve passes between the 2 heads of the ___________ and then courses between which 2 muscles to reach the wrist?
- pronator teres
- flexor digitorum superficialis and flexor digitorum profundas
