ASET Certification in Neurophysiologic Intraoperative Monitoring (CNIM) Practice Exam 2026 - Free CNIM Practice Questions and Study Guide

The formation of peripheral nerves, including the ulnar and femoral nerves, is primarily due to the contributions from the dorsal and ventral rami. The spinal nerves emerge from the spinal cord and immediately divide into these two rami. The dorsal rami are responsible for innervating the back muscles and skin, while the ventral rami supply the anterior and lateral parts of the trunk and the limbs.

The ulnar nerve, for example, originates from the brachial plexus, which is formed by the ventral rami of the lower cervical and upper thoracic spinal nerves. Similarly, the femoral nerve originates from the lumbar plexus, which also derives from the ventral rami of lumbar spinal nerves. This illustrates how the ventral rami are integral in forming various peripheral nerves that provide motor and sensory functions to different body parts.

Other answer options such as the white matter of the spinal cord and the cervical spinal cord do not form peripheral nerves directly. The white matter primarily consists of myelinated axons that facilitate communication between different regions of the central nervous system. The cervical spinal cord, while it gives rise to nerves, in itself does not constitute the peripheral nerves. Similarly, while the ventral ganglion