Lumbar Spinal Stenosis

Low back pain (LBP) has been estimated to affect approximately 30% of the adult population, and as many as 50% of those over the age of 65 years.

For those over the age of 65, a specific form of low back pain which can also produce lower extremity symptoms and significantly affect quality of life is lumbar spinal stenosis (LSS). LSS occurs when the spinal canal narrows and compresses the spinal cord and nerves at the level of the lumbar vertebra. Patients with LSS typically have LBP and lower extremity symptoms.  Heaviness in the legs often makes standing or walking for long periods of time very difficult.  Sitting is a particularly relieving position.

Like many other conditions, the degree of spinal degeneration on x-rays has little correlation with the signs and symptoms experienced by the patient.  Therefore, x-rays are of little benefit when trying to categorize low back patients or determine their prognosis.  The use of physical/clinical examination and patient history is likely to be of great benefit when trying to place patients into the LSS diagnostic category.  A Clinical Prediction Rule (CPR) was recently developed to diagnosis LSS once any problems of the vascular system were ruled out.

In diagnosing LSS, CPR uses a scoring system for patients:

  • 60-70 years of age = 2 points

  • > 70 years of age = 3 points

  • Onset over 6 months prior = 1 point

  • Relief with flexion (forward bending) = 2 points

  • Relief with extension (backward bending) = -2 points

  • Standing aggravates = 2 points

  • Intermittent claudication (leg heaviness/weakness) symptoms = 1 point

  • Urinary incontinence = 1 point

 

The higher the score, the more likely the patient has LSS. A total score of 7 or more signifies a higher likelihood that the patient is suffering from LSS.  Most importantly however, patients should receive a functional exam of the spine and lower extremity.

Patients with LSS experience leg symptoms during standing and walking which creates a backward extension of the low back.  In turn, the nerves are compressed where they exit between the lumbar vertebrae.  Relief is found with forward bending or sitting because it widens the space where the nerves leave the spine.  These patients are also found to have stiffness in their upper back and hip regions which can lead to further stresses in the low back area.

Management of patients with LSS would involve spinal traction/decompression to relieve the pressure on the nerves as they exit the spine.  Mobilizing/freeing up the upper back and hip region is needed to reduce any further backward stresses on the lumbar spine.  In addition to stretching the hip flexors, forward bending stretches of the low back are needed to relieve the compression on the lumbar area.  Lastly, core strengthening with emphasis on the front region is necessary to prevent backward stresses on the back.

If done correctly, patient function should improve which will allow walking, enhanced quality of life and continued independence.

 

Source:

  1. Lumbar spinal stenosis: diagnosis and management of the aging spine, Manual Therapy 2011; 16(4): 308-17.