Neuroanatomy Part 2: The Spinal Cord

1. Introduction to Neuroanatomy of the Spine

The spinal or vertebral column is a flexible bony structure that supports and protects the spinal cord. This chapter will present an overview of the importance of proper alignment of the spine as it connects to ligaments and tendons along with housing the spinal cord and nerve root openings to innervate muscles and internal organs.

2. Structural and Functional Neuroanatomy of the Spinal Cord

As the second major organ in the central nervous system (CNS), the spinal cord, or medulla spinalis, connects the brain to the rest of the body. It is important for clinicians to understand how the spinal cord assists the brain with optimal body function and movement. Discussion of each of the four main spinal cord regions, with associated anterior and posterior spinal nerve root function, along with upper and lower motor neuron pathways, will be presented.

3. Peripheral Nervous System: Somatic and Autonomic Branches

The spinal cord nerve root pathways relay messages (outside the brain and spinal cord) to organs and the periphery of the body through what is called the peripheral nervous system (PNS). This system houses both voluntary (somatic) and involuntary (autonomic) system branches. It is important for clinicians to understand normal pathophysiology of both to understand how organs act in times of stress or rest. This chapter will review the twelve cranial nerves and thirty-one pairs of spinal cord nerves within the PNS, along with related functions, both voluntary and involuntary, within the human body.

4. Performing a Neurological Assessment to Check Spinal Cord Function: Dermatomes, Myotomes, and Reflexes

Normal nerve impulse control and innervation is important for healthy function of the spinal cord and brain. The treating clinician must have a good understanding of the components of a comprehensive neurofunctional examination to determine this status for a patient. In addition to determining level of consciousness and verbal responses, the clinician must be able to demonstrate how to evaluate motor responses such as muscle strength, muscle tone, posture, reflexes, movement, sensation, and coordination. This chapter will present a quick overview of how to perform a simple motor and sensory examination to determine optimal spinal cord function.