Spondylolisthesis is where a bone in the spine (vertebra) slips out of position, either forwards or backwards.
It's most common in the lower back (lumbar spine), but it can also occur in the mid to upper back (thoracic spine) or the neck (cervical spine).
Spondylolisthesis isn't the same as a slipped disc, which is where one of the spinal discs between the vertebrae ruptures.
Symptoms of spondylolisthesis
Many people may not realise they have spondylolisthesis because it doesn't always cause symptoms.
Symptoms can include:
- lower back pain – which is usually worse during activity and when standing, and is often relieved by lying down
- pain, numbness or a tingling sensation radiating from your lower back down your legs (sciatica) – this occurs if the slipped vertebra presses on a nerve
- tight hamstring muscles
- stiffness or tenderness in your back
- excessive curvature of the spine (kyphosis)
The severity of these symptoms can vary considerably from person to person.
What causes spondylolisthesis?
There are five main types of spondylolisthesis, each with a different cause. Spondylolisthesis can be caused by:
- a birth defect in part of the vertebra – this can cause it to slip forward (dysplastic spondylolisthesis)
- repetitive trauma to the spine – this results in a defect developing in the vertebra, which can cause it to slip; this is known as isthmic spondylolisthesis and is more common in athletes such as gymnasts and weightlifters
- the joints of the vertebrae becoming worn and arthritic – this is known as degenerative spondylolisthesis and is more common in older people
- a sudden injury or trauma to the spine – such as a fracture, which can result in the vertebra slipping forward (traumatic spondylolisthesis)
- a bone abnormality – this could be caused by a tumour, for example (pathologic spondylolisthesis)
When to see your GP
You should see your GP if:
- you have persistent back pain or stiffness
- you have persistent pain in your thighs or buttocks
- your back curves outwards excessively
Your GP may examine your back, although there aren't usually any visible signs of spondylolisthesis.
Your GP may ask you to do a straight leg raise test, where you lie on your back while your GP holds your foot and lifts your leg up, keeping your knee straight. This is often painful if you have spondylolisthesis.
Spondylolisthesis can easily be confirmed by taking an X-ray of your spine from the side while you're standing. This will show whether a vertebra has slipped out of position or if you have a fracture.
If you have pain, numbness, tingling or weakness in your legs, you may need additional imaging tests, such as a computerised tomography (CT) scan or magnetic resonance imaging (MRI) scan. These more detailed scans will be able to help determine whether you have a compressed nerve in your back.
The way spondylolisthesis is treated will depend on your symptoms and how severe they are. In most cases non-surgical treatments will be recommended first.
Initial treatments for spondylolisthesis may include:
- a short period of rest, avoiding activities such as bending, lifting, contact sports and athletics
- anti-inflammatory painkillers, such as ibuprofen, or stronger painkillers available on prescription can help reduce pain and inflammation
- physiotherapy – simple stretching and strengthening exercises may help increase the range of motion in your lower back and hamstrings
- if you have pain, numbness and tingling in your legs, corticosteroid injections around the compressed nerve and into the spinal canal may be recommended
These measures will only provide temporary symptom relief, but your symptoms may disappear completely with time.
Back braces sometimes used to be recommended for some people with spondylolisthesis. However, there are concerns that bracing may actually weaken the spine and fail to improve symptoms.
Surgery may be recommended if non-surgical treatments are ineffective and your symptoms are severe, persistent, or suggest you have a compressed nerve in your spine.
The exact surgical procedure you need will depend on the type of spondylolisthesis you have.
It usually involves fusing the slipped vertebra to the neighbouring vertebrae using metal screws and rods, and a piece of your own bone taken from an area nearby. The screws and rods are usually left in place permanently.
In some cases the spinal disc being compressed between your vertebrae may also be removed. It will be replaced by a small "cage" containing a bone graft to hold your vertebrae apart.
The operation is performed under general anaesthetic, which means you'll be unconscious while it's carried out.
Surgery is often effective at relieving many of the symptoms of spondylolisthesis, particularly pain and numbness in the legs.
However, it's a major operation that involves up to a week-long stay in hospital and a recovery period lasting months, where you have to limit your activities.
Spinal surgery for spondylolisthesis also carries a risk of potentially serious complications, including:
- infection at the site of the operation
- a blood clot developing in one of the veins in your leg – known as deep vein thrombosis (DVT)
- damage to the spinal nerves or spinal cord, resulting in continuing symptoms, numbness or weakness in the legs, or, in rare cases, some degree of paralysis or loss of bowel or bladder control
Because of the possibility of complications, make sure you discuss the operation in detail with your doctor or surgeon before deciding to have surgery.
Read more about lumbar decompression surgery, a type of spinal surgery used to treat compressed nerves in the lower (lumbar) spine.