Morphometry of the nerve trunks of the thoracic limb of the yorkshire terrier
The study was conducted on five Yorkshire Terriers of different genders that were delivered from St. Petersburg clinics after forced euthanasia to the Department of animal anatomy of SPBSAVM. The age of the animals ranged from 5 to 10 years; weight ranged from 2.4 to 3.2 kg. Complex of anatomical and topographic methods, such as subtle and gross anatomical dissection, was used for isolation of nerve trunks of thoracic limbs from surrounding tissues. Dissection of the nerve trunks was performed according to Vorobyov's method. We carried out dissection according to this method using binocular magnifying glass and falling drops. To prepare the solution we mixed 2% solution of acetic acid with water at 1:1 ratio. We filled a straight glass tube with this mixture so that it was dripping to the preparation through that tube. A falling drop loosened the tissues and allowed us to perform subtle anatomical dissection. In this study we have found that the innervations of thoracic limb is realized by nerves of the brachial plexus, which is located laterally to the vertebral column and passes either as two or three nerve trunks or as individual nerves along with the subclavian artery and vein. The brachial plexus lies more ventrally than scalene muscle and medially to scapula it is divided into nine nerves: suprascapular nerve, subscapular nerve, axillary nerve, musculocutaneous nerve, cranial thoracic nerve, caudal pectoral nerve, ulnar nerve, median and radial nerves. Ulnar, median and radial nerves are the main nerve trunks located in the tissues of free thoracic limb area and innervating it.