describe the features of the radius that allow it to have 2 proximal joints
- radius has articular surface for humerus
- its head projects into radial fossa
- head also accomodates for capitulum of humerus
- head has medial curvature to allow it to fit into distal ulnar notch –> allows pronation/supination of forearm
describe the features of the ulna that allow it to have 2 proximal joints
- ulna has an olecranon and coronoid process
- allows it to articulate with corresponding fossa in humerus
- trochlear notch to accomodate trochlear on humerus
what are the features of the elbow joint that stabilise it?
- radial and ulnar collateral ligament
- annular ligament of radius
what does the annular ligament of the radius do?
encloses proximal radio-ulnar joint
allows head of radius to rotate up and over ulna
what connects 2 bones of forearm?
interosseous membrane
proximal and distal radio-ulnar joints
what are the 8 carpal bones?
scaphoid lunate triquetrium pisiform trapezium traoezoid capitate hamate
what is a sesamoid bone?
a bone that grows and is embedded with a tendon
what are the boundaries of the cubital fossa?
lateral: medial border of brachioradialis
medial: lateral border of pronator teres
line between 2 epicondyles of humerus
what are the contents of the cubital fossa?
brachial artery
median nerve
biceps tendon
in general, where do the muscles of the forearm arise?
the epicondyles of humerus, shaft and heads of radius and ulna
what are the different compartments of the forearm?
- anterior superficial
- anterior deep
- posterior superficial
- posterior deep
what muscles are found in the anterior superficial compartment?
- pronator teres
- FCR
- PL
- FCU
- FDS
what is the function of muscles in the anterior superficial compartment?
- flexion of wrist
- in conjugation with extensors, adduction and abduction
- flexion of fingers
what is the innervation of these muscles in the anterior superficial compartment?
median nerve
apart from FCU which is ulnar nerve
what are the muscles in the anterior deep compartment?
- FDP
- FPL
- PQ
what is the function of the these muscles?
- flexion of digits
- pronation of wrist
what innervates the anterior deep compartment?
all median nerve
except for ulnar half of FDP
what muscles are in the posterior superficial compartment?
- brachioradialis
- ECRL
- ECRB
- extensor digitorium
- extensor digiti minimi
- ECU
what are the functions of the muscles in this compartment?
- extend wrist
- adduction and abduction
- extension of fingers
what is this compartment innervated by?
radial nerve
what muscles are in the posterior deep compartment?
- aconeus
- supinator
- EPL
- abductor pollicis longus
- extensor policis brevis
- extensor indices
what are the functions of the muscles in this compartment?
supination, extension and abduction of thumb and index finger
what are the muscles in this compartment innervated by?
radial nerve
what is a retinaculum?
extension of fascia that covers tendons, preventing them from bowing
what is an important distinction b/ flexor and extensor retinaculum?
flexor retinaculum is a lot thicker because it covers more tendons
what makes up the boundaries of the anatomical snuff box?
Lateral: tendons of abductor pollicis longus and extensor pollicis brevus
medially: tendon of extensor pollciis longus
what runs in the anatomical snuff box?
radial artery
what bone articulates with the proximal carpal bones?
the radius
articular membrane of distal radio-ulnar joint prevent ulna from articulating with carpal bones
what are the principal movements of the elbow joint?
flexion and extension
what are the principal movements of the wrist joint?
- flexion and extension
- abduction
- adduction
- supination
- pronation
what are the muscles involved in elbow flexion?
- brachialis
- biceps brachii
- coracobrachialis
what are the muscles involved in elbow extension?
triceps brachii
what muscles are involved in wrist flexion?
- FCR
- FCU
- palmaris longus
what muscles are involved in wrist extension?
- ECRL
- ECRB
- ECU
what muscles are involved in wrist abduction?
- FCR
- ECRL
- ECRB
what muscles are involved in wrist adduction?
- FCU
- ECU
what are the main spinal nerves responsible for shoulder joint movement?
C5-7
what are the main spinal nerves responsible for elbow flexion?
C5 and 6
what are the main spinal nerves responsible for elbow extension?
C7 and 8
what are the main spinal nerves responsible for movements of the wrist muscles?
C6-8
what are the main spinal nerves responsible for movements of hand muscles?
C8-T1
explain how the brachial artery becomes the anterior and posterior interosseus branch?
- after passing through cubital fossa, brachial artery bifurcates into radial and ulnar arteries
- immediately ulnar artery gives off common interosseus branch
- this splits into the ant and post interosseus branches
describe the passage of the ulnar artery
runs up medial side of arm
in the wrist it passes through guyon’s canal with ulnar nerve
describe the passage of the radial artery
passes on lateral part of arm
moving into anatomical snuffbox