Spinal Cord Injury (SCI) is severe damage to the human spinal cord. There are three different segments of the neural tissue which can result in motor and sensory loss. Damage can be differentiated as
1) death of the neurons within the spinal cord; 2) disruption of neuronal pathways due to damaged cells; and 3) destruction of the protective myelin sheath carrying nerve signals from the brain to different organs of the body. In general, a spinal cord injury is a result of severe damage to distinct parts of the spinal cord such as the vertebral column, ligaments, or spinal disks. In most reported cases of SCI, damage can be due to trauma or disease. Apart from the physical damage and complete dependency on caregivers, SCI can be emotionally damaging as well. This is due to dependency even for basic mobility, negative attitudes, and frequent mood swings. These can lead the patient to be excluded from social participation. More than 30% of the reported cases of SCI showed significant signs of depression and negative impact on overall health.
The human spinal cord is a fragile bridge connecting the brain with the other organs of the body. The spinal cord is encased in the protective covering of spinal vertebrae in the spinal column to prevent its damage from shock or injury. The central nervous system, which is the brain and the spinal cord, is made up of millions of cells, which coordinate and communicate to pass on the information from the brain to the other organs of the body via spinal cord.
This information is passed in the form of electrical signals which are then decoded by the specific organ. Each neuron is made up of a cellular body with a long slender projection called a nerve fiber. These fibers are attached to other fibers to form a dense network of cells. In general, neurons carrying messages down the cord from the brain to the other organs of the body are known as Motor Neurons. These neurons control the muscles of important internal organs of the body such as the heart, stomach, and intestine.
The neurons traveling up the cord to the brain are known as Sensory Neurons which carry sensory information from skin, joints, and muscles to control a person’s ability to sense, touch and regulate body temperature. These neurons are insulated from the outer side by a coating of Oligodendrocytes and myelin sheath. These cells insulate the neuron to protect them from sudden damage and shock. If any of the above types of cells are affected due to sudden damage such as shearing, laceration, stretching or shock, then the network of cells is disturbed due to which the passage of information between the brain and the spinal cord is compromised.
