What is lumbar spondylolisthesis?

Spondylolisthesisis a condition in which a vertebra in the lower spine slips forward over another. The vertebrae are the building blocks of the spine, and the discs provide the cushioning between these bones. If one these vertebrae shift forward compared to the vertebrae below it, this can cause narrowing of the spinal canal and put pressure on the nerves. If the nerves are getting pinched, this can cause pain, numbness, and weakness radiating down the legs. It can also cause lumbar stenosis, a crowding of the nerve roots, which can cause cramping in the legs which is worse with activity.

What causes spondylolisthesis?

Spondylolisthesis usually occurs because of degenerative arthritis of the lower back in patient above the age of 40, or it occurs due to stress fracture that develops during the teenage years. Degenerative changes in the lumbar spine can cause widening of the joints in the spine, which allows for the vertebrae to shift forward. Repetitive hyperextension of the lumbar spine can also cause stress fractures in an area of the bone called the pars interarticularii. This can occur during the teenage years when the bones are still growing. A stress fracture in the pars can cause the vertebral body to slip forward. Other causes of spondylolisthesis include congenital spine defects present at birth, traumatic injury, or bone disease such as osteoporosis or infection.

What are the symptoms?

Symptoms of spondylolisthesis range from mild to severe and may include:

  • Lower back pain
  • Pain in the thighs and buttocks
  • Pain radiating down the leg
  • Numbness and tingling in the legs
  • Weakness in the legs
  • Cramping or stiffness in the legs

Symptoms generally worsen with walking or activity and improve with rest or leaning forward.

How is spondylolisthesis diagnosed?

In addition to a complete physical exam and patient history, your doctor can use X-rays to determine if one of your vertebrae has slipped out of place. You might also have an MRI or CT scan to further evaluate for nerve impingement and help guide treatment.

What is the treatment?

Many patients with spondylolisthesis will improve with non-surgical measures. These include rest, non-steroidal anti-inflammatory medication, corticosteroids, epidural injections, a back brace, or physical therapy.

Surgery may be needed if the slippage progressively worsens or if the symptoms do not respond to conservative treatment and begin to interfere with activities of daily living. The most common surgical treatment is a decompressive laminectomy and fusion. In this procedure the surgeon removes the bone spurs, disc fragments, or any tissue that is pressing on the nerves to relieve the compression off the nerves and spinal canal. Because the vertebrae is shifted forward, the vertebrae affected are fused together to provide stability. Typically, rods and screws are used to hold the vertebrae firm as the fusion heals. There are different types of surgical fusion techniques including the standard approach called a Transforaminal Interbody Fusion (TLIF) as well as a minimally invasive approach called Extreme Lateral Interbody Fusion (XLIF) or Anterior Lumbar Interbody Fusion (ALIF).

In select cases, minimally invasive surgical treatment options are available. Advantages of minimally invasive surgery include smaller incisions, less tissue and muscle damage, less bleeding, and shorter hospital stays. However, not everyone is a candidate for minimally invasive procedures. A surgeon who is trained in both techniques is the best person to determine the most appropriate surgical option for the patient. A consultation with the proper surgeon is crucial in making that determination.