Spinal Cord Injury
Spinal Cord Injury (SCI) is damage to the human spinal cord into three different segments of the neural tissue leading to a severe form of motor and sensory loss.
The kind of damage can be differentiated as:
- Death of neurons within the spinal cord.
- Disruption of neuronal pathways due to damaged cells.
- Destruction of the protective myelin sheath carrying nerve signals from the brain to different organs of the body.
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 also be emotionally damaging. More than 30 percent of reported cases showed depression had a negative impact on functional improvement of overall health.
How Prevalent is SCI?
Since SCI is associated with the loss of mobility, paralysis and mortality due to other opportunistic infections, it’s known as one of the most critical and disastrous medical conditions. Every year around 2 to 5 million people are reported to suffer from spinal cord injury. On average, middle-aged and young adult males are more susceptible due to avoidable causes such as road accidents, injuries, falls or violence. Mortality associated with SCI has been observed to be the highest immediately after the injury. The risk of mortality doubles with the severity level and is observed to be strongly influenced by the immediate availability of the best medical care. Preventable secondary opportunistic infections are also reported to be a major cause of death in many SCI patients especially in lower income groups.
About 90 percent of patients in the age group of 20-45 have been reported to face other complications such as limited employment, decreased quality of life, and severe depression.
Factors Responsible for SCI
In general, a spinal cord injury is a result of severe damage to different parts of the spinal cord such as the vertebral column, ligaments or the spinal disks. This typically originates from sudden trauma to the spinal cord such as fracturing, crushing or dislocating one or more vertebrae. Additional damage has been reported due to excessive bleeding, swelling, inflammation and other opportunistic infections.
The most common reported causes of Spinal Cord Injury are:
- Motorcycle road accidents or accidents without protection
- In the aged population or women with osteoporosis, SCI is often due to a fall
- About 15-20 percent of cases result from violent encounters, i.e., gun shots, knife wounds, fights, etc.
- Athletic injuries
- Cancer, arthritis, osteoporosis and inflammation of the spine
Symptoms Associated with SCI
In general, the severity and area of injury are factors of concern in cases of SCI.
Based on severity of injury, SCI is classified as:
Complete SCI – If all sensory and motor functions are lost
Incomplete SCI –If some degree of motor and sensory function is retained
In addition, the extent of movement loss can be segmented into two parts:
Tetraplegia: All the limbs including arms, hands, legs, pelvic organs are paralyzed
Paraplegia: Part of the body is paralyzed
Apart from what’s already stated, common signs and symptoms can include:
- Functional loss of movement
- Functional loss of sensory organs such as ability to sense heat, cold and touch
- Loss of bladder control
- Changes in sexual activity including sexual sensitivity and fertility
- Difficulty in breathing and coughing
Emergency signs and symptoms after the injury requiring immediate medical attention include:
- Extreme pain and pressure in lower back, neck and head
- Weakness, lack of coordination or paralysis in any part of the body
- Tingling sensation especially in the lower limbs
- Maintaining an awkward posture
What Goes Wrong in SCI?
The human spinal cord is a fragile bridge connecting the brain with other organs of the body. The spinal cord is encased in a protective covering of spinal vertebrae of the spinal column to prevent damage from shock or injury. Our central nervous system is made up of millions of cells which coordinate and communicate to pass on information from the brain to other organs of the body via the 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 the 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 other organs of the body are known as motor neurons. These neurons control the muscles of some of the important internal organs of the body such as the heart, stomach, intestine, etc. The neurons travelling up the cord to the brain are known as sensory neurons, carrying sensory information from skin, joints and muscles to control our ability to sense, touch and regulate temperature.
These neurons are insulated from the outer side by the coating of oligodendrocytes and myelin sheath. These cells insulate the neuron to protect them from sudden damage and shock.
If any of the above type of cells is affected due to sudden damage such as shearing, laceration, stretching or shock, then the network of cells is disturbed and the passage of information from the brain to the spinal cord and vice versa is halted.