Muscles of the Arm. 



301 



Bursa ni. subscapularis 



Processus coracoideus 



Ligamciituni trausvorsuiu scapulae siiperius 

 yi. onioliyoideus (cut tlirough) 



Tendo capitis 

 longi 111. liicipitis "" 



Capsula I 



articularis 



Vagina mucosa 

 iiitertubercularis 



M. 

 coracobrachialis *kt 



M. 

 pectoralis major - 

 (cut tlirough) 



Bursa 

 111. pectoralis - 

 majoris 



(caput 

 breve ~ " 

 uieeps . 

 bracliii I caput 

 I longum 



Scapula 



M. triceps M. teres major 



brachii 

 (caput longum) 



- M. biceps brachii 



346. Muscles on the anterior surface of the right 



shoulder joint, viewed from in front. 

 (The claviciila, mm. di'ltnideiis, pectoralis major and subscapularis have been removed.) 



Bursa m. pectoralis majoris see p. 263. 



M. biceps brachii (see also Figs. 308, 310, 342, 343, 347 and 348). Form: rounded, 

 spindle-shaped, thick. Position: on the anterior surface of the upper arm; above, at its 

 origins, it is covered by the mm. pectoralis major and deltoideus. Origin: by two heads. 

 Caput longiun : from the tuberositas supraglenoidalis scapulae and from the labrum gienoidale 

 liv a long, thin tendon, which extends first lateralward within the cavity of the shoulder joint, 

 then curves markedly downward in the sulcus intertubercularis (see also Fig. 231) and is 

 accompanied in its course by a prolongation of the joint -capsule, the varjhia mucosa iater- 

 tuberculaiis (see also p. 180). Caput b'eve: by a narrow, flat, shorter tendon from the proc. 

 coracoideus, at first fused with the m. coracobrachialis. Insertion: both heads extend down- 

 ward and unite to form a spindle-shaped muscle-belly, the fibers of which, a little above the 

 elbow joint, go over for the most part into a flatly roimded , thick tendon , partly , also , into 

 a superficial thin tendinous plate. The latter, lacertus fibrosus (0. T. semilunar fascia), runs 

 obliquely medianward and downward in front of the m. pronator teres and becomes lost in the 

 fascia antibrachii; the tendon proper, bending into the depth, becomes attached to the tuberositas 

 radii fbwsa bicipitoradialis and bursa cubitalis inter ossea see Fig. 348). Action: it lifts 

 the upper arm forward, flexes the fore -arm and supinates it, especially, when it is flexed. 

 Innervation: n. miisculocutaneus. 



Spaltebolz, Atlas. 20 



