The nervous territories of the brachial plexus in Chinchilla lanigera

Abstract

For the study concerning the Brachial Plexus (BP) and nervous territories of chinchillas (Chinchilla lanigera) 10 animals were used. After the removal of the skin, the indetification of the thoracic limb, pectoral area and thoracic and abdominal walls was made. Then, compresses of glacial acetic acid at 3% were applied to these areas, in order to improve the observation of the nerves. In the studied animals, the emergence of the BP was observed to be from the sixth cervical nerve to the first thoracic nerve. These four roots make the trunks of the nerves whose ventral branches constitute their arrange and territorial distribution. From these four trunks arise the 12 nerves that constitute the BP. These nerves may be formed by a single medullary segment - monosegmentar (suprascapular, cranial pectoral, thoracodorsal), or by two ou more segments, plurisegmentar (subscapular, axillary, musculocutaneous, lateral thoracic, caudal pectoral, long thoracic, median, ulnar and radial). Therefore, constancy in origin, muscle, joint and bone innervation was observed, and can confirm the existence of a clearly defined pattern of the delimitation of nervous territories.