THE HUMERUS 



89 



inserted into a triangular rough area below the anterior part. The medial tuber- 

 osity (Tuberositas medialis) is less salient, and consists of anterior and posterior 

 parts; the anterior part forms the medial boundary of the intertuberal groove 

 and furnishes insertion to the medial branch of the supraspinatus above, and the 

 posterior deep pectoral muscle below; the posterior part gives attachment to the 

 subscapularis muscle. The intertuberal or bicipital groove (Sulcus intertuberalis)i 

 is situated in front; it is bounded by the anterior parts of the tuberosities, and is 

 subdivided by an intermediate ridge. - The groove is covered in the fresh state by 



Intertuberal 

 {or bicipital) Lateral 

 groove tuberosity 



Deltoid 

 tuberosity 



Lateral 



condyloid 



crest 



Coronoid 

 fossa 



Medial 

 condyle 



Lateral 

 condyle 



Lateral 

 epicondyle 



Medial 

 epicondyle 

 Olecra- 

 non fossa 



Fig. 63. — Left Humbrus_of~Horse; Lateral View. 

 1, Rough area to which tendon of infraspinatus is 

 attached; 2, crest; 3, depression for attachment of 

 lateral hgament. 



Lateral 

 tuberosity 



Deltoid 

 tuberosity 



Musculo- 



spiral 



groove 



Lateral 



condyloid 



crest 



Lateral 



epicondyle 



Intertuberal 



(or bicipital) 



groove 



Medial 

 tuber- 

 osity 



Teres 

 tuber- 

 osity 



Nutrient 

 foramen 



Coronoid 



fossa 

 Medial 

 epicondyle 



Lateral 

 condyle 



Medial 

 condyle 



Fig. 64. — Right Humerus of Horse; Front View. 

 1, Rough area for attachment of extensor carpi 

 rac^*.alis and extensor digitalis communis; 2, synovial 

 fossa. 



cartilage, and lodges the tendon of origin of the biceps brachii muscle. Just below 

 the intermediate ridge is a small fossa in which several foramina open. 



The distal extremity has an oblique surface for articulation with the radius 

 and ulna, which consists of two condyles of very unequal size, separated by a ridge. 

 The medial condyle (Condylus medialis) is much the larger, and is crossed by a 

 sagittal groove, on the anterior part of which there is usually a synovial fossa. Pos- 

 teriorly the groove extends upward considerably above the rest of the articular 

 surface and reaches the olecranon fossa, and this part articulates with the semilunar 



iThe name "intertuberal" is designative of the position of the groove, while the term 

 ''bicipital" has reference to its occupation by the tendon of the biceps brachii. The term "sulcus 

 intertubercularis" is also in common use. 



