THE FRONT OF THE ARM 



107 



Supraspinatus 



Subscapularis 



... Crest of the 

 lesser tubercle 



Pectoralis major 

 ^- Teres major 



Deltoid 



"~ Coraco-brachialis 



Both heads swell out into 

 elongated fleshy bellies, 

 which, at first, are merely 

 closely applied to each 

 other, but afterwards are 

 united in the distal third 

 of the arm. Towards the 

 bend of the elbow the 

 fleshy fibres converge upon 

 a stout, short tendon, which 

 is inserted into the dorsal 

 part of the tuberosity of 

 the radius. The insertion 

 will be more fully examined 

 at a later period, but it 

 may be noticed, in the 

 meantime, that the tendon 

 is twisted so as to present 

 its margins to the front 

 and dorsal aspect of the 

 limb, and, further, that a 

 bursa mucosa is interposed 

 between it and the smooth, 

 volar part of the radial 

 tuberosity. 



The dissector has al- 

 ready taken notice of the 

 lacertus fibrosus, and has 

 separated it, artificially, 

 from the deep fascia of the 

 arm, and of the forearm. 

 Observe now that it springs 

 from the anterior margin 

 of the tendon of the biceps 

 brachii, and also from the 

 short head of the muscle. 

 It is supplied by the mus- 

 culo-cutaneous nerve and 

 is a supinator of the fore- 

 arm and a flexor of the 



elbow-joint. FlG ' J 5- -Anterior aspect of Humerus with 



_ J _ _ _ Muscular Attachments mapped out. 



M. Brachialis (O.T. 



Brachio-radialis 



Extensor carpi 

 \- radialis 

 jongus 



Extensors 



Pronator teres 

 and flexors 



