Stenosis

Stenosis: what does it mean?

The word stenosis means narrowing. Narrowings can occur in various places in the back. We list them here and explain whether, and if so what, can be done about them.

1. Lumbar stenosis

Lumbar stenosis is a narrowing of the spinal canal – a canal stenosis – in the lower back. The term lumbar canal stenosis would actually be better, but in common language people usually just say canal stenosis or lumbar stenosis.

The spinal canal is the space through which all nerves from the brain pass towards organs, skin, and limbs. For the most part, this happens via the spinal cord and in the lower back via a bundle of nerve roots. This is all safely enclosed in a kind of sac filled with cerebrospinal fluid. Normally, the nerves in that sac do not get pinched.

That can be the case if the canal is narrowed.

The cause of lumbar stenosis

Bone growth on the inside of the spinal canal is a major culprit. In addition, the ligaments in the spinal canal can thicken, as can the vertebral joints and their capsules. A bulging intervertebral disc often also plays a role. All these abnormalities gradually worsen with increasing age.

The size of the spinal canal can naturally vary quite a bit, which means one person may experience narrowing symptoms much sooner than another.

Symptoms of lumbar stenosis

If the space in the spinal canal becomes really too narrow, nerves can get compressed and this can lead to:

• Back pain
• Pain and fatigue in the legs (especially when standing and walking)*

* Usually the complaints affect both legs, but it can also be just one leg.

The pain usually decreases when the back is kept slightly rounded, for example by walking with a slight bend.

What can you do for lumbar stenosis?

You cannot do anything about the abnormalities in the spinal canal yourself. However, you can take them into account when sleeping. Avoid lying flat on your stomach and preferably not on your back either. The lower back then arches inward and the space in the spinal canal becomes (even) smaller.

Best sleeping posture for lumbar stenosis

The best is to sleep on your side, with a slightly curved back and a body pillow between the knees. In that position, the tension in the back is lowest and the space in the spinal canal is largest. In our article about sleeping posture you can read how to optimally improve your sleeping posture.

Are there surgical options?

Certainly. The space in the spinal canal is then enlarged. This can be done both in the traditional way (through a large incision in the back) and with an endoscope (small incision on the side).

2. Lateral stenosis

Lateral stenosis is a reduction of the space in the corner at the front/side of the spinal canal. It is actually also a canal stenosis, but localized. It can lead to somewhat different complaints than a ‘regular’ canal stenosis.

Lateral stenosis on the right (bone growth marked in black)

The cause of lateral stenosis

Bone growth in the corner of the spinal canal is usually the main cause, often combined with a bulging intervertebral disc. Again, an age-related issue.

Complaints in lateral stenosis

This corner of the spinal canal is the place where the nerve roots exit. A narrowing in this area can therefore cause compression of the nerve roots. These complaints can then arise: 

• Pain in one leg (usually one leg)
• Pain in the leg when arching the back (standing and walking)

Just like with canal stenosis, the pain can decrease by keeping the back slightly rounded.

What can you do with lateral stenosis?

You cannot do anything yourself about the abnormalities in the spinal canal. However, you can take it into account when sleeping. When lying flat, for example on your back, the lower back is quite hollow and the space in the spinal canal is smaller.

The best is to sleep on your side, with a slightly bent back and a body pillow between the knees. In this position, the tension in the back is lowest and the space in the spinal canal is greatest. Read more on our page about the sleeping position.

Are there surgical options?

Yes, this stenosis can also be surgically removed, both in the traditional way and with an endoscope.

3. Foraminal stenosis

In foraminal stenosis, there is a narrowing of the foramen. This is the opening in the spine between two vertebrae, where the nerve root exits.

Foraminal stenosis on the right, viewed from above (cross-section)

The cause of foraminal stenosis

Here, bone growth is not the main cause, but a hernia. Bone growth also occurs, both at the front and back of the foramen. And here too, anatomy plays a role: the foramen can naturally be somewhat small. Furthermore, the foramen can also be narrower due to a bulging disc.

Complaints in foraminal stenosis

These complaints can occur due to the nerve root being pinched:.

• Sharp, burning pain in the leg on the side of the stenosis.
• Muscle weakness, such as foot drop (unable to lift the foot)
• Tingling and loss of sensation in the leg

Just like with canal stenosis and lateral stenosis, the pain can decrease by keeping the back slightly rounded. This increases the space in the foramen a bit.

What can you do with foraminal stenosis/

Even with foraminal stenosis, you cannot remove the cause yourself. But here too, you can manage it as well as possible, which keeps the complaints limited and sometimes makes surgery unnecessary.

For example, choose to bike more often instead of walking; the back is then less arched. Sleep mainly on your side with a slightly curved back and with the help of a body pillow.

It is very important for this condition not to lie twisted with the lower back, as that can be very stressful for a nerve in a too narrow foramen. A body pillow helps well with this.

Are there surgical options?

Yes, but actually the foramen is only well accessible from the side with an endoscope. From the back, the foramen is almost impossible to reach surgically. Because the endoscopic technique (the PTED method) is only used in one clinic in the Netherlands, patients are sometimes told that this stenosis is not operable. The opposite is true: this stenosis can be excellently, quickly, and safely treated endoscopically.

4. Combinations of stenoses

Lumbar stenosis and lateral stenosis mainly develop due to bone growth and other age-related processes. This is partly true for foraminal stenosis as well. Partly not, because a hernia also occurs in young adults and a hernia is the main cause of this stenosis. However, for older people, multiple forms of stenosis can occur simultaneously.

Want to know more about stenosis and back complaints? Read the Book: Back Pain, Hernia, and Lumbago

Read more about sciatica, hernia, lumbago, treatment, exercises, surgical options, prevention possibilities, and much more:

Book Back Pain, Hernia, and Lumbago. How do I get rid of it?

Authors:

Dr. Menno Iprenburg, orthopedic surgeon, affiliated with Herniakliniek Veenhuizen
Drs. Jan Willem Elkhuizen, physiotherapist, manual therapist, and movement scientist, co-founder of the website Ligwijzer.nl