Definition
A myelopathy is damage to the nerve cells of the spinal cord. The medical term is formed from the two ancient Greek words myelon – marrow and pathos – suffering. Depending on the cause of the damage to the spinal cord, a distinction is made between different forms.
The location of the spinal cord damage is decisive for the symptoms; whether the spinal cord of the cervical, thoracic or lumbar spine is affected. The damaged section of the spinal cord can no longer perform its normal function and neurological deficits such as paralysis or sensitivity disorders occur. The diagnosis is made with the help of imaging techniques (for example, MRI). The therapy depends on the cause of the myelopathy.
Symptoms
The symptoms of myelopathy can be very diverse and depend primarily on the region of the spinal cord injury. The cause of the myelopathy can also influence the clinical symptoms. In all forms of myelopathy, the damaged sections of the spinal cord are no longer able to perform their function in the nervous system correctly, resulting in neurological deficits.
These are, on the one hand, sensory disturbances such as tingling pain or a feeling of numbness. On the other hand, patients complain about disorders of the musculoskeletal system such as muscle weakness or paralysis of the muscles. This can affect both arm and leg muscles.
This can lead to gait disorders in the course of the disease. In addition to mobility disorders, problems of bowel or bladder emptying (bladder and rectum dysfunction) can also occur. A herniated disc is usually accompanied by severe pain in the affected section of the spine, which may radiate into the arms and/or legs on both sides.
Causes
The damage to the spinal cord can be caused by various mechanisms. In compression myelopathy, pressure on the tissue causes damage to the spinal cord. This pressure can be caused by tumors, such as metastases from tumors of the spinal column or meninges.
Herniated discs are often the cause. When the inner core of the intervertebral disc slips into the spinal canal, pressure is exerted on the spinal cord located within. A narrowing of the spinal canal as in spinal canal stenosis can also cause a compression myelopathy.
A rarer cause is osteosclerosis, in which excessive formation of bone tissue leads to a narrowing of the spinal canal. In addition to compression myelopathy, reduced blood flow also leads to damage to the nerve cells in the spinal cord. Circulatory disorders occur in the case of vascular malformations or vascular constrictions (stenoses).
Acute blood loss can also lead to an undersupply of the spinal cord in shock. These forms of myelopathy caused by circulatory disorders are also called vascular myelopathy. The third group is radiation myelopathy, which can cause damage to the spinal cord during radiotherapy.
Furthermore, a fracture of the vertebral body can lead to injury to the spinal cord. The spinal canal is a canal formed by the vertebral arches at the rear edge of the spine; the spinal cord runs through it. Stenosis is therefore understood to be the narrowing of this canal.
This can be caused, for example, by the formation of new bones as a result of degenerative changes with increasing age, whereby these osteophyte attachments reach into the spinal canal and can displace the nerve fibers of the spinal cord. A typical symptom of spinal canal stenosis is that after a short distance walking is restricted due to pain. In contrast, no symptoms are reported when riding a bicycle.
This is due to the forward bent posture, which relieves the spinal cord. A magnetic resonance tomography is performed for diagnosis. A surgical therapy to remove the excess bone material in the spinal canal so that the spinal cord has more space again.