The spinal cord
The spinal cord enables communication between the brain and the rest of the body. It contains nerve cells, called neurons, and bundles of nerve fibres, or axons, that carry signals to and from the brain. All the information needed to initiate and control movement travels down the spinal cord from the brain to the muscles of the body.
Signals from every part of the body also pass up the spinal cord carrying sensory information (such as touch, pressure and heat) to the areas of the brain that deal with these sensations and our responses to them.
Causes of traumatic spinal cord injury
The majority of spinal cord injuries are due to preventable causes such as falls, road traffic accidents or sports injury.
Males are most at risk in young adulthood (20-29 years) and older age (70+). Females are most at risk in adolescence (15-19) and older age (60+). Studies report male-to-female ratios of at least 2:1 among adults.
Spinal cord injury is associated with a risk of developing secondary conditions that can be debilitating and even life-threatening—e.g. deep vein thrombosis, urinary tract infections, muscle spasms, osteoporosis, pressure ulcers, chronic pain, and respiratory complications.
Types of injury
Doctors classify injuries as either complete or incomplete. In a complete injury, the spinal cord is sufficiently damaged across the whole of its width that there is complete loss of sensation and muscle control below the level of injury.
In an incomplete injury, the injury spreads across part of the spinal cord; some areas away from the injury remain intact or at least intact enough to retain some function. People with incomplete injuries can have some sensation and/or movement control below the level of injury.
The American Spinal Injury Association (ASIA) have developed International Standards for Neurological Classification of SCI Standards.These can be found here.
How an injury progresses
When the spinal column is damaged, for example by fracture or dislocation, the bony vertebrae can compress or bruise the fragile spinal cord. Although the initial injury leads to severed axons and the death or damage of many neurons outright, many neurons and axons remain intact, at least for a while.
Unfortunately, when cells die, they release toxic chemicals that cause uninjured neurons in the surrounding area to die also. This increases the overall damage and can double the size of the affected area in the first hours and days after injury. This is often referred to as secondary damage.
As the injury stabilises over the following weeks and months, dead and dying tissue is cleared and the body forms scar tissue in the damaged region. Sometimes the damaged spinal cord is left with large cavities as a result.
Other causes of spinal cord injury
- Degenerative orthopaedic causes
- Spinal cord haemorrhage (haematomyelia). Vascular malformations etc.
- Spinal cord stroke (infarct)
- Transverse myelitis (infections)
- Thoracoabdominal aortic aneurysm (TAAA)
- Central cord syndrome (upper motor function)
- Brown-Sequard Syndrome (hemisection)
Benefitting other neurological conditions
Our research into spinal cord injury repair and recovery is very relevant to other conditions such as stroke, multiple sclerosis, motor neurone disease, cervical spondyolotic myelopathy, dementia and Parkinson's. The scientific breakthroughs we make are likely to have a positive impact on people suffering many debilitating conditions.
Our research into cell behaviour, bladder and bowel control, sexual function and sensory recovery, for example, will also impact people who suffer these complications.