What is the spinal cord?
The extension of the brain
The spinal cord is the extension of the brain through the spinal column and it allows the circulation of all nervous messages between the brain and the rest of the body.
REFLEXES
Coordinating certain reflexes (for example when removing your hand from a hot hob, directly without passing the nervous information to the brain)
DRIVE TRANSMISSION
Transmit motor information to the muscles. It is made up of nerve fibers that relay sensory or motor information, as well as neurons specific to the spinal cord.
SENSORY TRANSMISSION
Transmit sensory information to the brain
Spinal Cord Anatomy
The spinal cord is part of the Central Nervous System.
It consists of 24 vertebrae (plus 9 fused sacro-coccygeal vertebrae):
-7 cervical vertebrae C1-C7
-12 chest T1-T12;
-5 lumbar L1-L5
Connected to the spinal cord are the spinal nerves. They are responsible formotor skills and sensitivity of the limbs, sphincters and perineum. Each spinal nerve is formed by the union oftwo roots spinal, onedorsal sensory and the otherventral motor.
These spinal nerves transmit information from different levels of the spinal cord depending on their position in the spine:
8 cervical nerves (C1 to C8)
These nerves located in the neck provide mobility and sensitivity to the upper limbs, neck, upper chest and diaphragm.
12 thoracic nerves (T1 to T12)
These nerves located on the upper part of the back provide mobility and sensitivity to the trunk and abdomen.
5 lumbar nerves (L1 to L5) + 5 sacral segments (S1-S5)
Located in the lower part of the back, these nerves ensure the mobility and sensitivity of the lower limbs as well as the functioning of the bladder, intestines and sexual organs.
Spinal cord injury: explanations
Spinal cord injury, or “spinal cord injury” can have manymultiple causes: accidents of life or illness can be responsible for these lesions.
A spinal cord injury can cause aparaplegia (paralysis of the lower limbs) or tetraplegia (paralysis of the lower and upper limbs) causing sensory and motor losses but also genito-sphincter disorders. The messages that the brain wishes to transmit to the motor and sensory functions no longer pass, or pass badly.
Take the example of a highway: if it is bombed, a crater is formed and prevents vehicle traffic in both directions. This creates a traffic jam or a strong slowdown.
We have always believed that it was possible to repair this traffic lane by making a bridge allowing vehicles to circulate again: that the information between the brain and the rest of the body circulates again.
This lesion causes a more or less significant loss of mobility or sensitivity.
Depending on the neurological level of spinal cord involvement and the extent of the lesion,different functions will be affected.
There are two types of spinal cord injury:complete lesions and incomplete lesions.
In the case of a complete lesion, the paralysis affects the entire part of the body located below the lesion.
In the case of an incomplete lesion only part of the spinal cord is damaged. In this case, part of the mobility or sensitivity may be retained.
Associated disorders
– Pain.
– Sphincter, bladder and intestinal disorders.
– Genital-sexual disorders.
– Respiratory disorders.
– Stiffness called spasticity that causes pain.
– In some cases, atotal loss of tone which is the cause of significant muscle wasting and other associated disorders.
– In the event of a cervical and upper back injury: affected people suffer from hypothermia in a cold environment, because their body is not able to transmit the signal of the cooling of the body to the brain. The high heat is also poorly tolerated because people with spinal cord injuries do not sweat below the level of the injury, which prevents the body from cooling down properly.
Science is changing day by day: more than 10 years ago, we thought it was impossible to repair a spinal cord injury, believing that neurons could no longer grow back after being severed. Except,we have proven otherwise. The human body is a marvel!