Spinal stenosis and slipped vertebra

What is spinal stenosis?

Inside the spine there is a canal through which the spinal cord and nerves pass. In spinal stenosis this canal narrows and presses on the nerves. It is seen most often in the lower back and affects the legs.

The narrowing usually comes on slowly, over years or decades. With age, discs get shorter, lose their spongy quality and may bulge into the canal. Bones grow bony spurs and ligaments thicken. For this reason it is seen mostly in people around 60 or older. A narrow canal does not always cause symptoms.

What is a slipped vertebra?

In a slipped vertebra (spondylolisthesis), one vertebra slips forward over the vertebra below it. The wear-related type, which comes from wear in the small joints of the spine, most often affects the fourth lumbar vertebra over the fifth, and usually people over 50. The slip can narrow the canal, which is why the two are described on one page.

Symptoms

• pain, weakness or numbness in the legs, calves or buttocks
• cramping in the calves when walking, which forces the patient to sit and rest several times
• sciatica-like pain running into the thigh and leg, in one or both legs
• pain that eases when leaning forward, sitting or lying down
• in a slipped vertebra: pain in the lower back or thigh, muscle spasm and tightness at the back of the thigh

In rare cases, weakness in the leg or loss of bladder and bowel control develops. These need urgent assessment.

Who is this page for?

• middle-aged and older people who walk less because of leg pain or cramping
• people whose MRI or X-ray report says spinal stenosis or a slipped vertebra
• people who have tried non-surgical treatment for several weeks without help

Diagnosis

The surgeon diagnoses it from your history, an examination and imaging:

• A plain X-ray shows the bones and the alignment of the spine.
• A CT scan shows the size and shape of the canal.
• An MRI shows the spinal cord, the nerve roots and the tissue around them.

The scan result has to match your symptoms. More is in the article “How to understand your spine MRI report”.

Treatment without surgery

Treatment starts here:

• Exercise and physiotherapy. The aim is to strengthen and protect the spine and build endurance and flexibility. Treatment usually lasts 4 to 6 weeks.
• Medicine. Anti-inflammatories and painkillers. Many patients manage with over-the-counter medicine; severe or lasting pain may need a prescription.
• Epidural injection to reduce inflammation.
• Weight control, stopping smoking and strengthening the bones, if the doctor recommends it.

The effect of an injection is sometimes temporary and may last several months. Details are on the “Treatment without surgery” page.

When is surgery considered?

Surgery is considered when non-surgical treatment has not helped. Signs that a patient may be a candidate for surgery:

• back or leg pain limits daily life
• leg weakness, foot drop or numbness is getting worse
• control of the bladder or bowel has been lost
• standing or walking has become difficult
• medicine and physiotherapy have not worked
• general health is fairly good

What does the operation involve?

Before the operation the surgeon explains which approach suits you. These are the general approaches:

• Laminectomy (decompression). Part of the bone at the back of the canal (the lamina) is removed to make room for the nerves. It is the most common operation. It is sometimes combined with removing part of a disc or with fusion.
• Laminotomy and foraminotomy. A smaller opening to free the nerve where it leaves the spine.
• Fusion (joining vertebrae). It is needed only in a small number of patients, for example when there is instability, and the decision is usually made before the operation. There are different methods of fusion.

Lumbar decompression surgery usually takes 2 to 4 hours or more and is done under general anaesthetic. This page does not say which method or equipment your surgeon uses; ask at your visit.

Recovery

An example for lumbar decompression surgery:

• going home about 2 to 5 days after the operation
• back to work in about 4 to 6 weeks
• full return to normal activities in about 12 weeks
• painkillers may be needed for a few weeks

Speed of recovery varies from patient to patient. Physiotherapy, and sometimes occupational therapy, helps with getting back to activity.

Risks

Serious complications of lumbar decompression surgery are uncommon but may include:

• a leak of spinal fluid, which may need another operation
• nerve damage or paralysis
• continuing back pain
• slipping of other vertebrae, which may need another operation

The risks of anaesthetic and surgery depend on age, general health and other conditions. The surgeon and anaesthetist go over these with you before the operation.

When to call

Call 115 now or go to an emergency department (115 is Iran’s emergency number) if you have:

• numbness around the anus or genitals
• being unable to pass urine, or loss of control of urine or stool
• severe or worsening weakness or numbness in both legs

This condition (cauda equina syndrome) needs emergency admission, and the later it is treated, the greater the chance of permanent paralysis and incontinence.

Contact a doctor the same day if:

• leg weakness or foot drop is new or getting worse
• pain or numbness suddenly becomes severe
• after surgery: redness, warmth or discharge from the wound, fever, or new numbness and weakness in the leg

Every patient’s treatment plan is different; ask your doctor about your own situation.