what happens if brain and spinal cord are non functional
Answers
Explanation:
Traumatic spinal cord injury usually begins with a sudden, mechanical blow or rupture to the spine that fractures or dislocates vertebrae. The damage begins at the moment of primary injury, when the cord is stretched or displaced by bone fragments or disc material. Nerve signaling stops immediately but may not return rapidly even if there is no structural damage to the cord. In severe injury, axons are cut or damaged beyond repair, and neural cell membranes are broken. Blood vessels may rupture and cause bleeding into the spinal cord’s central tissue, or bleeding can occur outside the cord, causing pressure by the blood clot on the cord.
Within minutes, the spinal cord near the site of severe injury swells within the spinal canal. This may increase pressure on the cord and cut blood flow to spinal cord tissue. Blood pressure can drop, sometimes dramatically, as the body loses its ability to self-regulate. All these changes can cause a condition known as spinal shock that can last from several hours to several days.
There is some controversy among neurologists about the extent and impact of spinal shock, and even its definition in terms of physiological characteristics. It appears to occur in approximately half of the cases of spinal cord injury and is usually directly related to the size and severity of the injury. During spinal shock, the entire spinal cord below the lesion becomes temporarily disabled, causing complete paralysis, loss of all reflexes, and loss of sensation below the affected cord level.
The primary injury initiates processes that continue for days or weeks. It sets off a cascade of biochemical and cellular events that kills neurons, strips axons of their protective myelin covering, and triggers an inflammatory immune system response. This is the beginning of the secondary injury process. Days, or sometimes even weeks later, after this second wave of damage has passed, the area of destruction has increased—sometimes to several segments above and below the original injury.
Changes in blood flow cause ongoing damage. The major reduction in blood flow to the site following the initial injury can last for as long as 24 hours and become progressively worse if there is continued compression of the cord due to swelling or bleeding. Because of the greater blood flow needs of gray matter, the impact is greater on the central cord than on the outlying white matter. Blood vessels in the gray matter also become leaky, sometimes as early as 5 minutes after injury, which initiates spinal cord swelling. Cells that line the still-intact blood vessels in the spinal cord also begin to swell, and this further reduces blood flow to the injured area. The combination of leaking, swelling, and sluggish blood flow prevents the normal delivery of oxygen and nutrients to neurons, causing many of them to die.
Explanation:
When the spinal cord is damaged, information from the brain can no longer regulate reflex activity. Reflexes may become exaggerated over time, causing muscle spasticity. Muscles may waste away or diminish due to underuse. If spasms become severe enough, they may require medical treatment.