Understanding and Treating Lumbar Stenosis

Low back pain is one of the most common health complaints, especially as people get older. One frequent cause is lumbar stenosis, which occurs when the spinal canal narrows and puts pressure on the nerves that run through it. While the term may sound complicated, the concept is straightforward—and understanding it can help you recognize symptoms early.

What Is Lumbar Stenosis?

Lumbar spinal stenosis is very common, impacting roughly 10–15% of older adults in the United States. Lumbar stenosis simply means narrowing within the lumbar spine. The spine is comprised of bones (vertebrae), discs that act as shock absorbers, joints that allow movement, and ligaments that provide stability. Together, these structures surround and protect the spinal canal—the space through which spinal nerves run. These nerves carry signals between the brain and the rest of the body.

After exiting the lumbar spine, these nerves supply sensation and strength to the legs and feet. When the canal narrows, those nerves can become compressed, leading to pain and other symptoms.

One helpful way to think about your spine like a freeway. In a healthy spine, the canal is a wide highway with multiple open lanes through which nerve signals can travel freely. When stenosis occurs, it is as if there are several lanes closed. Traffic slows, congestion builds, and signals struggle to get through.

Why Does the Spine Narrow?

The most common cause is simple wear-and-tear over time. As we age, several natural changes occur in the spine:

• The cushioning discs between vertebrae lose water and height.
• Joints in the spine can develop arthritis.
• Bone spurs may form as joints enlarge and discs degenerate.
• Ligaments that support the spine can thicken and stiffen.

These changes gradually lead to lessened space inside the spinal canal. Sometimes, the vertebrae themselves may become unstable and shift out of place (i.e. spondylolisthesis), further narrowing the canal.

Common Symptoms

Symptoms can vary from person to person, but they typically fall into two categories: back-related symptoms and nerve-related symptoms. Low back pain is often caused by arthritis and degeneration in the joints and discs of the spine.

Leg symptoms, on the other hand, occur when nerves are compressed. These may include:

• Shooting pain down the buttocks or legs
• Numbness or tingling
• Weakness
• Cramping or aching in the thighs or calves

This nerve-related pain is often referred to as sciatica, which describes irritation of nerves that contribute to the sciatic nerve.

A characteristic symptom of severe lumbar stenosis is leg cramping or aching that worsens when standing or walking, but improves when sitting or bending forward. Some people notice they can walk farther when leaning forward on a shopping cart, which slightly opens the spinal canal and reduces nerve pressure.

How Is It Diagnosed?

Doctors usually diagnose lumbar stenosis using a combination of medical history-taking, physical examination, and imaging studies. The most useful imaging study is an MRI scan, which allows physicians to visualize the nerves, discs, joints, and ligaments in detail and identify where compression is occurring. X-rays are also used to evaluate spinal alignment or instability.

Treatment Options

Lumbar stenosis can frequently be managed with non-surgical treatments. Common approaches include:

• Physical therapy: Strengthening core and back muscles helps stabilize the spine and reduce strain.
• Weight management: Reducing excess weight decreases stress on the spine.
• Activity modification: Adjusting posture, taking breaks during walking, or switching to activities like cycling can ease symptoms.
• Medication: Anti-inflammatory medications may reduce irritation around the nerves.

For patients with persistent nerve pain, epidural steroid injections may also help by reducing inflammation around compressed nerves. Relief may last weeks to months.

When Is Surgery Considered?

Surgery is typically considered only if symptoms remain severe or significantly limit daily life despite non-surgical treatment.

Surgical procedures are designed to relieve pressure on the nerves. The most common operation is a laminectomy, which removes part of the bone covering the back of the spinal canal to create more space for the nerves. In some cases, a spinal fusion may be added to stabilize the spine. Surgery for lumbar stenosis is generally very effective at improving leg symptoms and restoring mobility.

Don’t Ignore Persistent Back or Leg Pain

Many people try to “push through” pain, but early evaluation can make a big difference. Non-surgical treatments are often most effective before symptoms become severe.

If walking becomes difficult, leg pain increases with activity, or numbness and weakness develop, you should seek medical advice. With the right diagnosis and treatment plan, most people with lumbar stenosis can regain mobility and return to the activities they enjoy.

With expertise in spine surgery, anesthesiology, sports medicine, and rehabilitation, MarinHealth Spine Institute is the North Bay’s destination for comprehensive, personalized spine care. Call 415-925-8200 to make an appointment in Larkspur, Novato, or Petaluma.

To learn more about lumbar stenosis, listen to this short podcast.

Dr. Akash A. Shah is a fellowship-trained spine surgeon with expertise in both complex and minimally invasive spine procedures. He sees patients at MarinHealth Spine Institute | A UCSF Health Clinic in Larkspur, Novato, and Petaluma.