

SURFACE ANATOMY OF THE UPPER EXTREMITY 



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a zigzag line with a general convexity forward; when the arm is by the side the 

 highest visible serration is that attached to the fifth rib. 



The Deltoideus with the prominence of the upper end of the humerus produces 

 the rounded contour of the shoulder; it is rounded and fuller in front than behind, 

 where it presents a somewhat flattened form. Above, its anterior border presents 

 a slightly curved eminence which forms the lateral boundary of the infraclavicular 

 fossa; below, it is closely united with the Pectoralis major. Its posterior border 

 is thin, flattened, and scarcely marked above, but is thicker and more prominent 

 below. The insertion of Deltoideus is marked by a depression on the lateral side 

 of the middle of the arm. 



Flex. carp, rad. 

 Abd. poll long. 

 Ext. poll. brev. 



Lateral group of 

 antibrachinl muscles 



I Triceps lirachii 

 A nticubital fossa 3fediai epicondyle 



Coracobmchia Us 



Axilla 



Pectoralis major 



Flex. carp, ulnaris 

 Palmarin longus 



FIG. 1231. Front of right upper extremity. 



Of the scapular muscles the only one which influences surface form is the Teres 

 major; it assists the Latissimus dorsi in forming the thick, rounded, posterior 

 axillary fold. 



When the arm is raised the Coracobrachialis reveals itself as a narrow elevation 

 emerging from under cover of the anterior axillary fold and running medial to the 

 body of the humerus. 



Deltoideus 



Medial eminence 



Biceps brachii 



Lateral eminence 



Triceps brad ii \ 



Medial epicondyle 



Olecranon 



Head of ulna 

 Ext. carp, ulnaris 

 Flex. carp, ulnaris 



Anconceus 



FIG. 1232. Back of right upper extremity. 



On the front and medial aspects of the arm is the prominence of the Biceps 

 brachii, bounded on either side by an intermuscular depression. It determines the 

 contour of the front of the arm and extends from the anterior axillary fold to the 

 bend of the elbow; its upper tendons are concealed by the Pectoralis major and 

 Deltoideus, and its lower tendon sinks into the anticubital fossa. When the muscle 

 is fully contracted it presents a globular form, and the lacertus fibrosus attached 

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