Spinal Stenosis

Spinal stenosis is a narrowing of the spinal canal that is localized and can occur as a result of wear and tear on the spine. If the blood vessels and nerve fibers in the spinal canal are squeezed due to a narrowing, this can cause back pain and other complaints.

Characteristic here is pain in the area of the lower back, which increases in intensity when walking and radiates over the buttocks into the legs. An improvement of the pain can be noticed when bending the trunk forward.

Spinal stenosis is more common in older age. The area of the lumbar spine is predominantly affected by a narrowing of the spinal canal.

The most common reason for spinal stenosis is wear and tear of the spine. With increasing age, the space between two vertebrae becomes smaller, as the intervertebral discs located there lose fluid and consequently height. As a result, the ligaments lose their tension and thicken, causing the spinal segments to lose stability and become displaceable relative to one another (spondylolisthesis). The body reacts to this process by attempting to compensate by forming bony edge phenomena on the vertebral bodies (osteophytes). An enlargement of the vertebral joints (facet joints) can be caused by arthrosis of these.

Furthermore, increasing stress on the base and top plates of the vertebral bodies favors the development of spinal stenosis. This also leads to bone compression. In sum, these changes lead to a significant narrowing of the spinal canal (central stenosis). If, on the other hand, the narrowing mainly affects the intervertebral holes through which spinal nerves exit, this is referred to as lateral stenosis.

If the trunk muscles are untrained, these degenerative changes can lead to discomfort, since in this case the spine cannot stabilize on its own.

More rarely, other causes of spinal stenosis may also be present:

• Narrowing of the spinal canal from birth; in this case, the complaints already occur at the age of 30 to 40 years
• Narrowing as a result of spinal surgery
• Hormonal changes, e.g.: Cushing's disease
• Bone diseases, e.g: Paget's disease. In this disease, there is localized remodelling and growth of bones, especially in the lumbar spine, the pelvis or the upper and lower leg bones.

The general symptoms of spinal stenosis are varied and not very specific. They develop slowly over months and never appear suddenly.

Non-specific symptoms include:

• Back pain (lumbago) combined with limited mobility in the lumbar spine and muscle tension in the lower back.
• Back pain with often unilateral radiation into the legs (lumboischialgia)

As the severity of spinal stenosis progresses, the following symptoms occur:

• Disturbance of sensation in the legs
• Sensory disturbances in the legs, such as burning sensation, formication, feeling of coldness, cotton wool under the feet
• Feeling of weakness in the legs
• Bladder/rectal dysfunction
• Impaired sexual function

If the course of the disease is already advanced, the classic symptoms of spinal stenosis occur. For example, when sitting or in similar positions in which the trunk is bent forward, the symptoms improve. This can be explained by the fact that bending forward stretches the spine, widening the spinal canal and relieving the pressure on the nerves. This symptomatology is also called caudicatio spinalis.

Since the symptoms of spinal stenosis are usually non-specific, imaging techniques can help the doctor to identify the extent of the narrowing. X-rays can detect causes such as bony changes, vertebral body attachments, vertebral joint arthrosis, and disc degeneration. However, spinal stenosis itself cannot be detected on an X-ray, which is why computed tomography (CT) or magnetic resonance imaging (MRI) must be used, which can detect narrowing in the spinal canal. Magnetic resonance imaging has the advantage over computer tomography that soft tissue structures such as intervertebral discs or nerve roots are also visible. For this reason, this examination method is considered the preferred choice.

Another diagnostic method is myelography, in which contrast medium is administered into the dural sac that encases the spinal cord and the beginning of a nerve, and then an X-ray is taken. To ensure this examination, the patient must stretch and bend so that the doctor can see where the spinal cord or nerve is constricted.

The most reliable examination method is the CT (myelo-CT), which is more informative due to the contrast medium. If the patient has a pacemaker, for example, magnetic resonance imaging cannot be performed, which is why myelography and myelo-CT must be used. It is also useful to perform a myelo-core spin examination.

On the basis of a neurological examination, the possible extent of nerve damage can be detected. Laboratory tests (blood tests, cerebrospinal fluid tests) show whether other diseases are the cause of the symptoms.

The extent of the complaints determines the form of therapy. For example, the degree of narrowing has no apparent relationship to the discomfort.

The decision whether to proceed surgically or not depends on whether the back pain of the spinal stenosis is in the foreground or whether nerve damage is already present. In the latter case, surgery must be performed to prevent progression of the nerve damage.

Physiotherapy can help to alleviate the symptoms by training the trunk muscles. In addition, there are special walking exercises and helpful tips for everyday life. However, if the pain is more severe, pain therapy with medication should be considered. Wearing a corset can also be helpful, as it counteracts excessive curvature of the lumbar spine backwards and the associated narrowing of the spinal canal. However, care should be taken that the corset is not worn permanently, as this can lead to a regression of the trunk muscles. Some doctors also recommend acupuncture therapy for pain relief. If severe back pain occurs, a local anesthetic and cortisone can be administered directly into the spinal canal (epidural infiltration) for relief. Cortisone can reverse the pressure that causes the swelling and inflammation of the nerve for a certain time.

In some cases, spinal stenosis must be treated surgically. The goal here is to take the pressure off the nerve fibers (decompression surgery). One of the many surgical procedures is the partial or complete removal of the vertebral arch (hemilaminectomy or laminectomy). This is mainly used when:

• Nerve deficits such as paralysis, numbness or dysfunction occur.
• Activity is restricted by the complaints, such as restriction of the ability to walk or the work performed
• The abdominal press for defecation is prevented as a result of the severe pain

Depending on the cause, implants can also be used for treatment, which in their mode of action are similar to mechanical spacers between the vertebral processes and therefore keep the spinal canal free. Occasionally, the spinal column is also stiffened in the narrowed area (dorsal fusion).

Spinal stenosis is slowly progressive and can be treated in several ways. However, the causes of the stenosis cannot be eliminated. However, with the help of conservative therapy, spinal stenosis can be stabilized over several years. In this way, those affected experience relief from the symptoms without having to restrict their lifestyle.

The results of surgery are positive in most cases, as it goes well for the majority. Nevertheless, physiotherapeutic measures or, if necessary, pain treatment should be started immediately after the end of the therapy (conservative or surgical).