Lumbar Stenosis

CAUSES — SYMPTOMS — DIAGNOSIS — TREATMENT

The term lumbar spinal stenosis refers to a decrease in the space inside the spinal canal in the low back. This can cause a variety of symptoms. The radiological diagnosis of lumbar spinal stenosis must be distinguished from the clinical diagnosis of lumbar spinal stenosis. The reason for this is that the x-ray appearance of spinal stenosis is quite common with progressive aging and most patients with spinal stenosis have little or no symptoms and therefor do not need treatment. That being said, there are many patients with symptomatic lumbar spinal stenosis who are in need of treatment, conservative or surgical. The most common causes of lumbar spinal stenosis are congenital, acquired and a combination of both. Lumbar spinal stenosis refers to generalized tightness of the spinal canal. An associated problem is called lateral recess stenosis. In this condition, the spinal canal may be of adequate size but the lateral (side) portions are too narrow and cause pressure on the nerves as they exit the spine. The symptoms of both lumbar spinal stenosis and lateral recess stenosis may be very similar.

Lumbar Stenosis Causes

As mentioned in the introduction, the main causes of lumbar spinal stenosis are congenital, acquired and a combination of the two. Lateral recess stenosis is most commonly acquired. The causes of acquired stenosis include hypertrophy (enlargement) of the facet joints (joints that connect adjacent vertebrae), hypertrophy of the ligamentum flavum ("yellow ligament" that connects adjacent vertebrae), disc protrusion and spondylolisthesis (slippage of one vertebral body in relation to another). Most of these changes occur with use and aging and are difficult to prevent.

Lumbar Stenosis Symptoms

The most common symptom of lumbar spinal stenosis (and lateral recess stenosis) is pain. The pain can be located on one side or both. It can occur in the buttocks, thighs and lower legs. The pain (or in some cases discomfort or numbness and tingling) often worsens with walking or prolonged standing. It may be relieved my rest. Sitting, squatting and bending forward at the waist may all help relieve the symptoms. The standing time and walking distance to symptom appearance may vary. It can take anywhere from a few minutes to half an hour for relief to occur.

Lumbar Stenosis Diagnosis

As always, a careful history and physical examination are the first steps in diagnosis. It is important to distinguish a spinal problem from a vascular (blood vessel) problem. The symptoms are similar. A check of the pulses in the legs and feet may be helpful. In some cases, testing of the circulation in the legs may be necessary to distinguish a spine problem from a vascular problem. MRI scanning is very useful and may be diagnostic for the spinal problem. In some cases, myelogram and post-myelogram CT scanning may be needed. Flexion and extension (bending) x-rays may also be helpful in determining whether or not a fusion will be necessary. Electromyography and nerve conduction velocity testing (EMG/NCV) may be ordered by your doctor.

Lumbar Stenosis Treatment

In general, the initial treatment of lumbar spinal stenosis will be conservative (non-operative). This may include a trial of non-steroidal anti-inflammatory medications and a short course of physical therapy. In some cases, a trial of epidural steroid injections may be given. If conservative management is unsuccessful in relieving symptoms then surgery may be considered.

The most common surgical treatment for lumbar spinal stenosis is a laminectomy. This is an operation that involves the removal of the posterior (back) portion of the spine to allow more room for the nerves. Depending on the particular situation, more or less bone may be removed. In some cases, especially in the case of lateral recess stenosis, only the lateral portion of the bone may be removed. This allows decompression of the nerve roots with less bone removal. In some cases, particularly where spondylolisthesis is involved, a fusion procedure may be performed at the same time as the decompression. The surgical decision is tailored to each individual case.