Veterinary Anatomy GCVS

Note: All the notes provided us from gcvs 

recomended book Guide To The Dissection Of Dog By Howard E. Evans, PhD 

Lecture no 1

BONES OF THE THORACIC LIMB

Veterinary Anatomy  GCVS 1st semester

Scapula

The scapula a flat,roughly triangular bone,possesses two surfaces,three borders and three angles. The ventral angle is the distal or articular end that forms the glenoid cavity, and the constricted part that unties with the expanded blade is reffered to as the neck

The lateral surface of the scapula is divided into two nearly equal fossae,by a shelf bone,spine of the scapula The spine is the most prominent feature of the bone. It begins at the dorsl border as a thick, low ridge and becomes thinner and wider toward the neck. In all breeds the free border is slightly thickened,and in some it is everted caudally. The distal end is a trancated process, the acromion¸where part of the deltiodeus arises. On continuation of the spine proximally the omotransversarius attaches. The remaining part os the spine provides a place for insertion of the trapezius and for origin of that part of the deltoifeus that does not arise from the acromion.

The supraspinous fossa is the entire surface carnial to the spine of the scapula. The supraspinatus arises from all but the distal part of this fossa.

The infraspinous fossa, caudal to tha spine is triangular, with the apex at the neck. The infraspinatus arises from the infraspinous fossa.

Thae medial or costsal surface has two areas. A small proximal and carnial rectangular area, thae serrated face, serves as the insertion for the powerful serratus ventralis muscle. The large remaining part of the costal surface is the subscapular fossa, which is nearly flat and usually presents three straight muscular lines that converge distally. The subscapularis arises from the whole subscapular fossa.

The carnial border of the scapula is thin. Near the ventral angle the border is concave as it enters into the formatio of the neck. The notch thus formed is the scapular notch. The distal end of the carnial border thickens and, without definite demarcation at the carnial angle, is the continous with the dorsal border.

The  dorsal border extends from the carnial  to the caudal angles. In life it is capped by a narrow band of cartilage, but in the dried spicimen the cartilage is destroyed by ordinary perpration methods. The romboideus attaches to its border.

The dorsal borderextends from the cranialto

the caudal angles.In life it is capped by a narrow

band of cartilage, but in the dried specimen the car-tilage is destroyed by ordinary preparation meth-ods. The rhomboideus attaches to this border.

Just proximal to the ventral angle, the thick cau-dal borderbears the infraglenoid tubercle,from

which arise the teres minor and the long head of

the triceps. The middle third of the caudal border

of the scapula is broad and smooth; part of the sub-scapularis and the long head of the triceps arise

from it. Somewhat less than a third of the dorsal

segment of the caudal border is thick and gives

rise to the teres major.

The ventral angleforms the expanded distal

end of the scapula. The adjacent constricted part,

the neck,is the segment of the scapula distal to

the spine and proximal to the expanded part of the

bone that forms the glenoid cavity. Clinically, the

ventral angle is by far the most important part of

the scapula, because it enters into the formation of

the shoulder joint. The glenoid cavityarticulates

with the head of the humerus. Observe the shal-lowness of the cavity.

The supraglenoid tubercleis an eminence at

the cranial part of the glenoid cavity. The tuber-cle shows a slight medial inclination on which a

small tubercle, the coracoid process,can be dis-tinguished. The coracobrachialis arises from the

coracoid process, whereas the biceps brachii arises

from the supraglenoid tubercle.

Posted in: 1st semester