The rat brachial plexus was studied morphologically and the average numbers of the fascicles were studied by light microscope. For this purpose, we used 30 Wistar albino adult rats (16 males, 14 females; 180-250 g). The rats were anaesthetized by urethane (0.6 ml/100 g body weight injected i.p.). The brachial plexus was prepared for the microdissection technique and was evaluated in terms of its formation. Sections of the origin level of roots (C5, C6, C7, C8 and Th1) and the terminal branches (ulnar, median, radial (musculospiral), axillary (circumflex), and musculocutaneous nerves) were taken and the average numbers of fascicles were calculated. The results of our investigation show that the rat brachial plexus is formed by the inferior primary divisions of the last four cervical and the first thoracic of the spinal nerves (C5, C6, C7, C8 and Th1). C4 might join with C5, but we did not observe a connection between the Th2 and Th1. The diameters of the roots and terminal branches of the brachial plexus were approximately 0.5-1.2 mm and 0.5-1.1 mm, respectively. The numbers of fascicles for the roots and terminal branches were calculated to be approximately 2-4 and 1-4, respectively.

The rat brachial plexus was studied morphologically and the average numbers of the fascicles were studied by light microscope. For this purpose, we used 30 Wistar albino adult rats (16 males, 14 females; 180-250 g). The rats were anaesthetized by urethane (0.6 ml/100 g body weight injected i.p.). The brachial plexus was prepared for the microdissection technique and was evaluated in terms of its formation. Sections of the origin level of roots (C5, C6, C7, C8 and Th1) and the terminal branches (ulnar, median, radial (musculospiral), axillary (circumflex), and musculocutaneous nerves) were taken and the average numbers of fascicles were calculated. The results of our investigation show that the rat brachial plexus is formed by the inferior primary divisions of the last four cervical and the first thoracic of the spinal nerves (C5, C6, C7, C8 and Th1). C4 might join with C5, but we did not observe a connection between the Th2 and Th1. The diameters of the roots and terminal branches of the brachial plexus were approximately 0.5-1.2 mm and 0.5-1.1 mm, respectively. The numbers of fascicles for the roots and terminal branches were calculated to be approximately 2-4 and 1-4, respectively.