tailieunhanh - Figure Drawing - Individual Muscles - Front Limb

The supraspinatus together create the rounded front edge of the shoulder form (located at the base of the side of the neck). In the ox, however, the supraspinatus alone creates the front of the shoulder form (the subclavius is deep). DOG AND FELINE • Origin: Outer surface of the front portion of the scapula and the adjacent cartilage. • Insertion: Inner and outer front corners of the top of the humerus. • Action: Extends the shoulder joint, advancing the limb. • Structure: The belly of the supraspinatus is thin where it begins, on the outside of the top of the shoulder blade;. | 66 INDIVIDUAL MUSCLES FRONT LIMB HORSE DOG Supraspinatus HORSE AND OX Origin Outer surface of the front portion of the scapula and the adjacent cartilage. Insertion Inner and outer front corners of the top of the humerus. Action Extends the shoulder joint advancing the limb. Structure The belly of the supraspinatus is thin where it begins on the outside of the top of the shoulder blade it twists to face forward at the front of the shoulder joint and then splits before inserting into the two areas of insertion on the humerus. In the ox it is completely covered by thin muscles. In the horse a small piece of the middle of the belly comes to the surface and the subclavius muscle attached to the front of the supraspinatus and the supraspinatus together create the rounded front edge of the shoulder form located at the base of the side of the neck . In the ox however the supraspinatus alone creates the front of the shoulder form the subclavius is deep . DOG AND FELINE Origin Same as in the horse and the ox except no scapular cartilage is present. Insertion Single area of insertion on top of the humerus. Belly doesn t twist or split before inserting. Structure Although it is mostly covered by thin muscle the supraspinatus creates the front form of the shoulder. INDIVIDUAL MUSCLES FRONT LIMB 67 OUTSIDE VIEW OUTSIDE VIEW OUTSIDE VIEW FRONT N FRONT FRONT HORSE OX DOG Infraspinatus HORSE AND OX Origin Outer surface of the rear portion of the scapula and the adjacent cartilage. Insertion Outer side of the top of the humerus. Action Rotates the arm outward pulls the limb away from the body. Structure The infraspinatus lies on the outer surface of the rear portion of the shoulder blade. Its flat belly lying on the flat surface of the scapula contributes to the planar quality of the shoulder region. The trapezius and latissimus dorsi cover the upper portion of the muscle and the deltoid belly and its wide tendon cover the lower portion. Only a small part of the infraspinatus .