Spinal stenosis is the narrowing of the spinal canal. The spinal canal is the tubing system within the vertebrae through which the spinal cord and spinal nerves run. "Stenosis" in Greek means "choking". Spinal stenosis can occur any place in the spine, but most often occurs in the neck and low back. The low back pain accounts for a large percentage of spinal stenosis. In general, pain is worsened with backward bending of the spine (ex. walking uphill, climbing stairs) and classically relieved by forward bending of the spine (ex. touching toes or leaning on a shopping cart).

There are two ways to categorize spinal stenosis, either by specific site of the narrowing in the canal, or by the way the narrowing was acquired. The site of narrowing can be either in the central or the lateral position. Central stenosis impinges on the spinal cord or the cauda equina (the region after the spinal "cord" ends in the middle back and continues as separated "nerve tracks"). This type usually occurs from degeneration of bony and soft tissue structures which include discs, ligaments, and any part of the vertebral body including the facet joints which form a column at the back edge of the spinal canal. Lateral stenosis compresses the nerve roots in the intervertebral foramen (the area formed between vertebrae through which the nerves exit the spinal canal). The location of stenosis is very important as it creates different symptoms and thus may merit different treatment.

The pain experienced from spinal stenosis varies upon the site of compression. If the spinal "cord" is involved, it can cause midline neck/back pain. If compression progresses, it may lead to "myelopathy" (compression of the spinal cord) or cauda equina syndrome (compression of the distal tail of the cord). Symptoms include a drastic change in walking pattern, upper extremity spasms, lower extremity weakness, and bowel and bladder incontinence. When the site of entrapment is the intervertebral foramen, the arms and/or legs may be involved. There may be pain, numbness/tingling, cramping, and/or weakness in the involved limb. The spectrum of symptoms are from mild to severe, the latter requiring urgent attention (see low back pain section).

Your doctor will perform a detailed history and physical examination, including specialized maneuvers that will detect whether the pain is worsened by making the spinal canal smaller, or improved by making the canal larger. Radiographic imaging will further help to clarify the stenosis, as both the size of the canal, and the structures that make the canal smaller can be seen by X-ray and MRI.

Your doctor will determine whether you are appropriate for conservative treatment versus surgical treatment. Most cases of spinal stenosis can be treated conservatively with anti-inflammatory medications, strengthening programs and modalities in physical therapy. Interventional procedures such as epidural adhesiolysis injections (see treatment), and dorsal column stimulators are very helpful in non-surgical treatment of spinal stenosis, and often used for pain relief and to maximize the effects of physical therapy.