Spinal stenosis

The most frequent abnormalities are: Lumbosacral transitional anomalies Scoliosis Hyperyphosis Hyperlordosis Rectification Spondylolysis Spondylolisthesis Vertebral arthritis Facet arthritis Spinal stenosis Fissure, protrusion and disc herniation Postoperative fibrosis Dislocation of the coccyx Atlantoaxial Dislocation Sprain Whiplash Syndrome

What it is

It consists of the narrowing of the spinal canal within a specific segment. It usually occurs because the deforming bones that form the facet joint invade the canal, decreasing the available space for the medulla and the spinal root.

How it takes place

This is normally due to invasion of the spinal canal through deformation of the bones forming the facet joint. Moreover, in some subjects the canal is narrower than normal, facilitating compression of nerve structures. If no such compression occurs, the narrowness of the canal is of no importance.

Symptoms

Narrowing of the spinal canal does not cause pain or any other problem as long as there is no compression of any nerve structure.

If compression does occur, patients feel no pain when flexed forward -for example, when sitting-, since this posture separates the laminae of the two vertebrae that make up the facet joint and relieves pressure on the nerve structure. However, walking produces a progressive leg pain -not on the spinal column- to the extent that patients are compelled to sit: this is known as "intermittent pseudoclaudication or spinal claudication".

Risk

If deformation progresses, the degree of nerve compression may increase. This means that:

1. the distance the patient is able to walk may decrease,
2. the nerves that control the musculature may become compressed, causing loss of strength in the legs.

Diagnosis

Scanning can detect narrowing of the spinal canal. Magnetic Resonance Imaging can also detect it and provide better observation of any nerve compression.

Neurophysiological tests can be used to determine the existence of nerve compression, evaluate the possible effect of this and monitor evolution of the disorder.

Treatment

If spinal stenosis does not cause nerve compression, no action should be taken.

Surgery should be considered when the degree of nerve compression worsens progressively. For a thorough evaluation, nerve status evolution should be studied by two electromyograms performed with a period interval of 3 months between them.

However, spinal stenosis usually begins in older adults. It is quite necessary to assess the risks and the expected benefits of surgery in each individual case. Some of the existing recommendations based on scientific evidence establish that:

• Surgical treatment for spinal stenosis in elderly patients who can carry out their normal daily activities is usually not necessary unless the nerves that control the sphincters are affected, and fecal or urinary incontinence develops as a result.
• Decisions about treatment should take into account the patient's preference, lifestyle, other medical problems, and risks of surgery.
• It is strictly discouraged to make a surgical decision based on the degree of narrowing shown in MRI. It is the functional limitation - and not the image of a greater or lesser stenosis- that should justify the decision.
• - Surgical considerations are strictly discouraged within the first 3 months of symptoms.