What is Lumbar Spinal Stenosis?
Lumbar spinal stenosis refers to narrowing of the space available for the nerves in the lower back or lumbar spine. This is a very common problem with aging and although it is almost universally present in people over the age of 60 to some extent, it does not always cause symptoms.
Lumbar spinal stenosis can occur at any level of the lumbar spine and can affect the central canal or can affect the nerves as they exit the spinal canal. The precise location and nature of the narrowing can result in different types of symptoms.
Lumbar Spinal Stenosis Causes
The possible causes for spinal stenosis include:
Age: As a result of aging, wear and tear on the spine causes narrowing of the bone.
Inflammation of the bone joint such as in osteoarthritis and rheumatoid arthritis may affect the spine.
Heredity: Some individuals are born with narrowing of the spinal canal (congenital). Structural malformations of the involved backbone can cause narrowing of the spinal canal.
Spondylolisthesis is a condition in which one vertebra glides forward over the one below causing narrowing of the spinal canal.
Tumors of the spine.
Injury or trauma may either dislodge the spinal canal or cause fractures that produce bone pieces which may penetrate the canal. At times, injury compresses the nerve roots that can lead to severe pain.
The most cause of lumbar spinal stenosis is aging related changes to the spine. This is called degenerative disc disease.
While degenerative disc disease affects everybody as they age, it does not always result in lumbar spinal stenosis. Aging of the spine can also result in facet joint arthritis (also known as facet arthropathy).
When this occurs, it can result in narrowing of the central canal of the spine and result in lumbar spinal stenosis.
Other causes of lumbar spinal stenosis include disc herniations, scoliosis, spondylolisthesis.
Many of these conditions can be co-existent and all contribute to narrowing of the space available for the nerves and cause symptoms.
Lumbar Spinal Stenosis Symptoms
Spinal stenosis may result in lower back pain and pain down the legs. The common symptoms include:
Pain with prolonged sitting or standing
These symptoms usually gradually progress and worsen over time.
The characteristic symptom of lumbar spinal stenosis is pain which radiates into the buttocks and legs. While back pain is also often present with lumbar spinal stenosis, it is leg pain which is the hallmark of lumbar spinal stenosis symptoms.
Spinal stenosis which affects the central canal of nerves typically causes symptoms characterized by pain into both buttocks and the back of the legs that is worsened by walking, and is relieved by rest and leaning forward.
Patients often find that they have to lean on a shopping cart at the grocery store to be able to walk better.
These symptoms are known as neurogenic claudication. Lumbar spinal stenosis can also cause pain shooting down one leg in the distribution of a spinal nerve, which is known as lumbar radiculopathy or sciatica.
In addition to pain, lumbar spinal stenosis symptoms can include weakness, numbness, or tingling into the legs.
Lumbar Spinal Stenosis Diagnosis
The initial diagnosis of lumbar spinal stenosis begins with a careful history and physical exam. A history of leg pain that travels below the knee radiating from the back, or increasing difficulty walking because of pain going into both buttocks and legs is very characteristic of lumbar spinal stenosis pain.
Your doctor will ask how long the symptoms have been present and what treatments have been tried.
Your doctor will also ask about your general medical health, level of fitness and activity, and whether you smoke cigarettes as all of these factors can affect how best to treat lumbar spinal stenosis.
The physical exam will focus on looking at your standing posture, testing the function of the nerves to the legs, and also feeling the pulses in your legs. Decreased blood flow to the legs is another common cause of leg pain (called vascular claudication) and needs to be identified if present as the treatment is very different than the treatment for lumbar spinal stenosis.
Standing x-rays are helpful to rule out a spinal fracture or a spinal deformity such as scoliosis or a spondylolisthesis.
An MRI is obtained if a patient has failed to improve despite initial conservative treatment and the symptoms are persistent and allows visualization of the space available for the nerves in detail.
Lumbar Spinal Stenosis Non-Surgical Treatment
The non-surgical treatment options include:
Your doctor may prescribe pain medications and muscle relaxants to relieve pain and inflammation.
Rest and restriction of activities which exacerbate back pain.
Cold/hot packs to decrease pain due to muscle strains and spasms.
Start physical therapy as recommended by your doctor to stretch and strengthen the muscles.
Acupuncture or chiropractic treatment for chronic low back pain.
The initial treatment of lumbar spinal stenosis is almost always non-surgical unless there is a significant neurologic deficit such as severe weakness. The initial treatment usually begins with a low impact aerobic exercise program, physical therapy to strengthen the back and core muscles, and the use of anti-inflammatory medications such as NSAIDS.
Flexion-based exercises such as cycling are usually better tolerated by patients, as a flexed-posture of the spine slighly opens up space for the nerves and relieves symptoms.
If patients are overweight then weight loss is recommended as the additional load on the spine can increase lumbar spinal stenosis symptoms.
Patients that smoke are recommended to quit smoking as active cigarette smoking accelerates spinal degeneration and worsens lumbar spinal stenosis symptoms.
If these measures fail to provide significant relief, epidural injections are often recommended as these can sometimes help with lumbar spinal stenosis pain depending on the precise nature of the stenosis.
Lumbar Spinal Stenosis Surgery
If lumbar spinal stenosis symptoms have been present for more than 6-12 weeks and fail to improve with conservative treatment methods, lumbar spinal stenosis surgery can often lead to dramatic improvement in the leg pain symptoms.
Depending on the exact symptoms and the location of the spinal stenosis, there are a variety of surgical procedures that may be recommended.
These can include microdiscectomy, lumbar decompression, or a lumbar decompression and fusion.
These procedures can often be performed minimally invasively and are tailored to the patient’s specific problem and their goals for recovery.