Arm Flashcards
Brachial Fascia forms
a sheath for muscles of the arm.
Brachial Fascia sends among the muscles
two fibrous septa
- lateral intermuscular septa
- medial intermuscular septa
Functions of 2 septa
separates flexor muscles (anterior group) from extensor muscles (posterior group)
provides additional surfaces for muscle attachment
Lateral intermuscular septum is attached to
humerus lateral border, lateral supra-condylar ridge down to lateral epicondyle
medial intermuscular septum is attached to
thick and attached to humerus medial border and medial supra-condylar ridge down to medial epicondyle
Anterior/ventral/flexor muscles
biceps brachii
coraco-brachialis
brachialis muscle
biceps brachii muscle origin
2 heads
short- tip of coracoid process on scapula
long - supra glenoid tubercle of scapula
biceps brachii insertion
2 head unite to be inserted by:
bicipital tendon: into radial tuberosity
bicipital aponeurosis: into cubital fossa
action of biceps brachii
- powerful supinator when elbow is flexed
- flexes elbow
- tendon of long head steadies humerus
- short head helps in flexion of shoulder joint
coraco-brachialis muscle origin
coracoid process (like short head of biceps)
coraco-brachialis insertion
rough impression on shaft of humerus
coraco-brachialis action
assists in flexion and adduction of shoulder joint
relations of coraco-brachialis
pierced by: muscolo-cutaneous nerve
medial to biceps
brachialis muscle origin
- shaft of humerus
2. medial and lateral intermuscular septa
insertion of brachialis muscle
coranoid process and ulnar tuberosity
action of brachialis muscle
main flexor of elbow
triceps origin
3 heads
long: infra glenoid tubercle of scapula
lateral: groove on humerus
medial: shaft of humerus below groove
triceps insertion
inserted into olecranon process (near elbow) by tendon
triceps nerve supply
radial nerve in axilla gives branches to long and medial head
radial nerve in groove gives branches to lateral and medial head
triceps action
- powerful extensor of elbow joint
2. articularis cubiti draws capsule of elbow doing during extension
articularis cubiti
emerge from triceps and insert into fibrous capsule of elbow joint
musculo-cutaneous nerve origin
lateral cord of brachial plexus
roots C5,6,7
Course of musculo-cutaneous nerve
descends to …
pierces. .
pierces. .
becomes. .
Key words; muscles and lateral
- descends to axillary artery and brachial artery
- pierces coraco-brachialis and descends between biceps and brachialis muscles while supplying them
- pierces deep fascia and becomes superficial called the lateral cutaneous nerve which divides into branches. this supplies the skin of forearm and upper part of thumb
branches of musculo-cutaneous nerve & what it supplies
- muscular branch - coraco-brachialis, biceps and large part of bracialis
- cutaneous - supplies skin on forearm and skin of thumb
radial nerve arrises from
C5,6,7,8 and T1
course of radial nerve
in the axilla
in the arm
in front of the lateral epicondyle
in the axilla - descends on wall of axilla
in the arm :
upper- passes downward of brachial artery, separating it from triceps
middle- passes triceps to reach spiral groove
lower- pierces lateral intermuscular septum and reaches front of arm where it go between brachialis and brachio-radialis
lateral epicondyle - gives branch: posterior interosseous nerve and becomes the superficial radial nerve
branches of radial nerve in axilla
muscular : supply long and medial head of triceps
cutaneous : posterior cutaneous nerve : supplies skin on back of arm , from deltoid tuberosity to elblow
branches of radial nerve in spiral groove
muscular : to lateral and medial heads of triceps and anconeus
cutaneous :
lower lateral cutaneous nerve of arm : supplies skin on arm from deltoid tuberosity to elbow
branches of the radial nerve in the lower part of the arm
gives muscular branches to brachio-radialis and extensor capri radialis longus and part of brachialis muscle
(BBE)
terminal branches in front of lateral epicondyle
radial nerve ends by posterior interosseous branch and then continues superficial radial nerve
brachial artery beginning
teres major muscle
brachial artery is a continuation of
axillary artery
course of brachial artery
descends on shaft of humerus
passes to front of arm until it
descends between lateral and medial epicondyles of humerus
enters cubital fossa
end of brachial artery
cubital fossa 1 cm below elbow joint
what happens at the end of brachial artery?
divides into two terminal branches: radial and ulnar arteries
branches of brachial artery
SIMP NT
- superior ulnar collateral artery
- inferior ulnar collateral artery
- muscular branches
- profunda brachii artery
- nutrient artery to the humerus
- terminal branches
profunda brachii artery is
the largest and highest branch and descends in spiral groove of humerus with radial nerve
muscular branches supply the
biceps, brachialis, coraco-brachialis
terminal branches is
radial and ulnar arteries