the capsule of the shoulder joint. 
TRAPEZIUS 
Clavicle (cnt)}_ 
Coraco-clavicular ligaments 
MUSCLES OF THE SHOULDER. 
315 
artery are placed. The deep surface of the muscle is separated by a bursa from 
It is in contact with the coracoid process, the 
coraco-acromial ligament, and the attachments of the pectoralis minor and the 
Posterior cord of brachial 
plexus 
Short subseapular nerve 
Long subscapular nerve 
—Lower subscapular nerve 
-SERRATUS MAGNUS 
Mia Dorsal scapular artery 
DELTOID ath 
LonG HEAD \\ 
OF BICEPS 7 
SUBSCAPULARIS 
TERES MAJOR 
CoRACo- 
BRACHIALIS 
LATISSIMUS DORSI 
Ss A , Internal 
: * cutaneous branch 
Ss S of musculo-spiral 
S ~ A nerve 
‘PRricrps (long head) 
B f Short head 
ICEPS + 
eat Long head 
Nerve to inner head of 
criceps (war collateral) 
coraco-brachialis and short head of 
the biceps: with the capsule of 
the shoulder joint: with the head 
of the humerus, the long head of the 
biceps and the attachments of the 
subscapularis, supraspinatus, infra- 
spinatus, and teres minor: and 
with the upper part of the shaft of 
the humerus and the circumflex 
TRICEPS 
(inner head) 
Musculo-cutaneous 
Musculo-spiral nerve catcEnal 
aor uae inter. vessels and nerve. The most an- 
muscular : : 
septum terior part of the muscle is formed 
of parallel fibres, not uncommonly 
separate from the rest of the muscle 
tenon cue at their origin from the clavicle. 
rectee OLE fe These fibres may he continuous 
RADIALIS LONGIOR Oriomor With the trapezius over the clavicle. 
a ruxor == ‘The most posterior part arises by 
as rorcarw © & fascial origin from the spine of 
Radial nerve FLEXOR the scapula and the fascia over the 
—~PROFUNDUS 
DIGITORUM 
infraspinatus muscle. These por- 
tions are attached respectively to 
the front and back of the main 
tendon of insertion. The inter- 
mediate fibres are multipennate, 
attached above and below to three 
or four septal tendons, which extend for a variable distance from the origin and 
insertion of the muscle. 
. The supraspinatus arises from the supraspinous fossa and the deep fascia 
over it. It is directed outwards under the acromion process and coraco- — 
acromial ligament, to be inserted by a broad thick tendon into the uppermost 
‘Fic. 235.—TuHE Posterior WALL OF THE AXILLA AND THE 
FRONT OF THE ARM (the biceps being divided). 
