What is spondylolisthesis?
Spondylolisthesis is a condition involving spine instability, which means the vertebrae move more than they should. A vertebra slips out of place onto the vertebra below. It may put pressure on a nerve, which could cause lower back pain or leg pain.
The word spondylolisthesis (pronounced spohn-di-low-less-THEE-sis) comes from the Greek words spondylos, which means "spine" or "vertebra," and listhesis, which means "slipping, sliding or movement."
Is spondylolisthesis the same as spondylolysis?
Both spondylolysis and spondylolisthesis cause low back pain. They are related but not the same.
- Spondylolysis: This spine defect is a stress fractures or crack in spine bones. It’s common in young athletes.
- Spondylolisthesis: This condition is when a vertebra slips out of place, resting on the bone below it. Spondylolysis may cause spondylolisthesis when a stress fracture causes the slipping. Or the vertebra may slip out of place due to a degenerative condition. The disks between vertebrae and the facet joints (the two back parts of each vertebrae that link the vertebrae together) can wear down. Bone of the facet joints actually grows back and overgrows, causing an uneven and unstable surface area, which makes the vertebrae less able to stay in place. No matter what the cause, when the vertebra slips out of place, it puts pressure on the bone below it. Most cases of spondylolisthesis do not cause symptoms. If you feel leg pain, it can also be caused by compression or a "pinching" of the nerve roots that exit the spinal canal (the tunnel created by the interlocking vertebrae of the spine). The compression or pinching is due to the vertebrae slipping out of position and narrowing the needed space for the nerves.
What are the types of spondylolisthesis?
Types of spondylolisthesis include:
- Congenital spondylolisthesis occurs when a baby’s spine doesn’t form the way it should before birth. The misaligned vertebrae put the person at risk for slippage later in life.
- Isthmic spondylolisthesis happens as a result of spondylolysis. The crack or fracture weakens the bone.
- Degenerative spondylolisthesis, the most common type, happens due to aging. Over time, the disks that cushion the vertebrae lose water. As the disks thin, they are more likely to slip out of place.
Less common types of spondylolisthesis include:
- Traumatic spondylolisthesis happens when an injury causes vertebrae to slip.
- Pathological spondylolisthesis occurs when a disease — such as osteoporosis — or tumor causes the condition.
- Post-surgical spondylolisthesis is slippage as a result of spinal surgery.
How common is spondylolisthesis?
Spondylolisthesis and spondylolysis occur in about 4% to 6% of the adult population. It’s possible to live with spondylolisthesis for years and not know it, since you may not have symptoms.
Degenerative spondylolisthesis (which occurs due to aging and wear and tear on the spine), is more common after age 50 and more common in women than men.
When back pain occurs in teens, isthmic spondylolisthesis (usually caused by spondylolysis) is one of the most common causes.
Who is at risk for spondylolisthesis?
You may be more likely to develop spondylolisthesis due to:
- Athletics: Young athletes (children and teens) who participate in sports that stretch the lumbar spine, such as gymnastics and football, are more likely to develop spondylolisthesis. The vertebra slippage tends to occur during children’s growth spurts. Spondylolisthesis is one of the most common reasons for back pain in teens.
- Genetics: Some people with isthmic spondylolisthesis are born with thinner section of the vertebra called the pars interarticularis. This thin piece of bone connects the facet joints, which link the vertebrae directly above and below to form a working unit that permits movement of the spine. These thinner areas of vertebrae are more likely to fracture and slip. Degenerative spondylolisthesis also has a large genetic component.
- Age: As we age, degenerative spine conditions can develop, which is when wear and tear on the spine weakens the vertebrae. Older adults with degenerative spinal conditions may be at higher risk for spondylolisthesis. It becomes more common after age 50.
What is low-grade versus high-grade spondylolisthesis?
To determine how severe spondylolisthesis is, your healthcare provider gives it a grade:
- Low-grade (Grade I and Grade II) typically don’t require surgery. Low grade cases are usually seen in adolescents with isthmic spondylolisthesis and in almost all cases of degenerative spondylolisthesis.
- High-grade (Grade III and Grade IV) may require surgery if you’re in a lot of pain.
Will I need surgery for spondylolisthesis?
Your healthcare provider will start with nonsurgical options, such as rest and physical therapy. These treatments often relieve symptoms. Your healthcare provider may recommend surgery if you:
- Have high-grade spondylolisthesis.
- Experience severe pain.
- Tried nonsurgical treatments but still have symptoms.
What causes spondylolisthesis?
Overextending the spine is one of the main causes of spondylolisthesis in young athletes. Genetics may play a role, too. Some people are born with thinner vertebral bone. In older adults, wear and tear on the spine and disks (the cushions between vertebrae) can cause this condition.
What are the symptoms of spondylolisthesis?
You may not experience any symptoms of spondylolisthesis. Some people have the condition and don’t even know it. If you do have symptoms, lower back pain is typically the main one. The pain may extend to the buttocks and down the thighs. You may also experience:
- Muscle spasms in the hamstring (muscles in the back of the thighs).
- Back stiffness.
- Difficulty walking or standing for long periods.
- Pain when bending over.
- Numbness, weakness or tingling in the foot.