A case study of spinal cord injury
Instructor: Dr. Daniel Kifle
June 16, 2014
A Case of Spinal Cord Injury
1. Describe the functional anatomy of the spinal cord using the following terms: white matter, gray matter, tracts, roots and spinal nerves. The spinal cord consists of a superficial White matter and a deep Gray matter. The white matter consists of myelinated axons, which form nerve tracts and the Gray matter consists of neuron cell bodies, dendrites and axons. The white matter in each half of the spinal cord is organized into ventral, dorsal and lateral columns. Each column is subdivided into tracts also called pathways. A collection of axon inside the CNS is called a tract but outside the CNS it is called a nerve. Spinal nerves arise from numerous rootlets along the dorsal and ventral surfaces of the spinal cord. Six of these rootlets combine to form a ventral root and the other six to form a dorsal root. Dorsal roots contain only sensory axons, so action potentials are conducted to the spinal cord only and the ventral root contain motor axons so action potential is conducted away from the spinal cord. This means spinal nerves have both the sensory and motor axons. Tracts combine to form roots (dorsal and ventral), roots combine to form the Spinal nerve(twelve pairs) which are in the spinal cord. 2. Define the terms reflex and spinal reflex and identify the components of a reflex arc. A reflex is an automatic response to a stimulus produced by a reflex arc. It occurs without conscious thought. Reflexes are homeostatic. A spinal reflex is any reflex action mediated through the center of the spinal cord. A reflex arc is the nerve pathway involved in a reflex action including at its simplest a sensory nerve and a motor nerve with a synapse between. It consist of five components namely Receptor; Site of the stimulus action, Sensory Neuron; transmits afferent impulses to the central nervous system, Integration Center (interneurons) which is always within the
June 16, 2014
A Case of Spinal Cord Injury
1. Describe the functional anatomy of the spinal cord using the following terms: white matter, gray matter, tracts, roots and spinal nerves. The spinal cord consists of a superficial White matter and a deep Gray matter. The white matter consists of myelinated axons, which form nerve tracts and the Gray matter consists of neuron cell bodies, dendrites and axons. The white matter in each half of the spinal cord is organized into ventral, dorsal and lateral columns. Each column is subdivided into tracts also called pathways. A collection of axon inside the CNS is called a tract but outside the CNS it is called a nerve. Spinal nerves arise from numerous rootlets along the dorsal and ventral surfaces of the spinal cord. Six of these rootlets combine to form a ventral root and the other six to form a dorsal root. Dorsal roots contain only sensory axons, so action potentials are conducted to the spinal cord only and the ventral root contain motor axons so action potential is conducted away from the spinal cord. This means spinal nerves have both the sensory and motor axons. Tracts combine to form roots (dorsal and ventral), roots combine to form the Spinal nerve(twelve pairs) which are in the spinal cord. 2. Define the terms reflex and spinal reflex and identify the components of a reflex arc. A reflex is an automatic response to a stimulus produced by a reflex arc. It occurs without conscious thought. Reflexes are homeostatic. A spinal reflex is any reflex action mediated through the center of the spinal cord. A reflex arc is the nerve pathway involved in a reflex action including at its simplest a sensory nerve and a motor nerve with a synapse between. It consist of five components namely Receptor; Site of the stimulus action, Sensory Neuron; transmits afferent impulses to the central nervous system, Integration Center (interneurons) which is always within the
References: Field-Fote, Edelle C. Spinal Cord Injury Rehabilitation. Philadelphia, PA: F. A. Davis, 2009. Print. Vaccaro, Alexander R., Michael Fehlings, and Marcel F. Dvorak. Spine and Spinal Cord Trauma: Evidence-based Management. New York: Thieme, 2011. Print. Williams, Margie. Journey to Well: Learning to Live after Spinal Cord Injury. Newcastle, CA: Altarfire Pub., 1997. Print.