The spinal cord, or spinal cord (from the Latin medulla) is a structure of the central nervous system located within the spine. It allows the transmission of information between the brain and the body.

Position. The spinal cord starts from the medulla oblongata, located at the level of the brainstem, extends into the vertebral canal, and ends with the medullary cone at the level of the lumbar vertebrae.

Internal structure. Cylindrical in shape and flattened on the posterior and anterior surfaces, the spinal cord is made up of two substances:

• A gray substance, in the center, made up of the cell bodies of neurons
• A white substance, on the outside, made up of axons, that is to say the extensions of neurons

Along the spinal cord, mixed nerves emerge. they are made up of fibers from sensory neurons at the periphery and motor neurons from the brainstem or spinal cord. These mixed nerves form the 31 pairs of spinal nerves and are defined as follows: 8 pairs of cervical nerves, 12 pairs of thoracic nerves, 5 pairs of lumbar nerves, 5 pairs of sacral nerves, and one pair of coccygeal nerves.

The spinal cord widens into two areas:

• the cervical bulge, where the nerves for the upper limbs originate
• the lumbosacral bulge, where the nerves for the lower limbs originate

External structure. The spinal cord is surrounded by three membranes, from the outside to the inside: the dura, arachnoid, and pia mater (2). These form the spinal meninges (3). The spinal meninges as well as the vertebrae, muscles, ligaments and cerebrospinal fluid provide protection for the spinal cord.

Nerve impulse transport. The role of the spinal cord is the transmission of nerve information.

• Sensory information. Ascending nerve pathways, which correspond to sensory neurons, transmit sensory information to the brain.
• Motor information. Descending nerve pathways, which correspond to motor neurons, transmit motor impulses to different regions of the body.
• Reflex coordination center. The spinal cord is also involved in so-called reflex reactions.

Spinal cord injury. Some trauma can result in a severing of the spinal cord, which can result in irreversible paralysis.

• Paraplegia. It corresponds to a paralysis of the lower limbs and may be due to a lesion of the spinal cord at the level of the dorsal vertebrae.
• Tetraplegia. It corresponds to a paralysis of the four limbs and may be due to a lesion of the spinal cord at the level of the cervical vertebrae.

Multiple sclerosis. This pathology is an autoimmune disease of the central nervous system. The immune system attacks the myelin, the sheath surrounding the axons, causing inflammatory reactions. The symptoms can be numerous, including motor or sensory disorders. (4)

Drug treatments. Depending on the pathology, different treatments are prescribed to reduce pain and inflammation.

Surgical treatment. Depending on the type of pathology, surgery may be performed.

Physical treatment. Physical therapies, through specific exercise programs, can be prescribed such as physiotherapy or physiotherapy.

Physical examination. First, a clinical examination is performed in order to observe and assess the symptoms perceived by the patient.

Medical imaging exam. In order to assess damage to the spinal cord, a cerebral and spinal CT scan or a cerebral MRI may in particular be performed.

Lumbar puncture. This exam allows the cerebrospinal fluid to be analyzed.

Much scientific research is underway to repair damage to the spinal cord. In 2014, the journal Cell Transplantation published a major surgical success on the spinal cord. It constituted a transplant of nasal nerve cells at the level of the lesion of a patient suffering from paraplegia. After 2 years, the patient regained the ability to walk using a walker (5).