THE DELTOID MUSCLE. 



199 



MUSCLES AND FASCIA OF 

 THE SHOULDEK. 



Fascije. — The deep fas- 

 cia binds together the mus- 

 cles of the shoulder \^ith 

 considerable firmness, and 

 over the back part of the 

 deltoid and infraspinatus, 

 muscles assumes a tendin- 

 ous appearance. A strong 

 and somewhat isolated por- 

 tion, bound down to the 

 posterior and axillary mar- 

 gins of the scapula, covers 

 the infraspinatus and teres 

 minor muscles as far as 

 they are left uncovered ])y 

 the deltoid muscle. On 

 reaching the posterior bor- 

 der of the deltoid muscle, 

 this aponeurosis divides in- 

 to two layers, of which the 

 deeper is continued beneath 

 the deltoid to the shoulder- 

 joint, and the more super- 

 ficial forms a thin aponeur- 

 otic covering of that muscle, 

 becoming more and more 

 slender as it passes for- 

 wards, and is attached to the 

 lower border of the spine. 



Fig. 169. — SuPEKFiciAii Mus- 

 cles OF THE ShoULDKU AND 



Upper Limb, fkom befoke. 

 (A. T.) A 



1, pectoralis major ; 1', its 

 clavicular portion ; 2, deltoid, 

 its clavicular part ; 2', its acro- 

 mial part ; 3, biceps brachii ; 

 3', its tendon of insertion ; 3", 

 its aponeurotic slip ; 4, brachi- 

 alis anticus ; 4', its inner and 

 lower portion ; 5, inner tead of 

 the triceps ; 5', lower part of 

 the same, seen arising from be- 

 hind the intermusciilar septum. 

 The explanation of the remaining 

 references will be found in the 

 description of fig. 179. 



Muscles. — Tlie deltoid 

 muscle is of a triangular 

 form and coarsely fascicu- 

 lated, and extends from the 

 most prominent part of the 

 shoulder down a third of 



J^tMf//i 



