Prolapsed disc - Diagnosing a slipped disc

Your GP will usually be able to diagnose a slipped disc from your symptoms and medical history.

You will also have a physical examination, where your GP will test your:

• posture
• reflexes
• muscle strength
• walking ability
• sensation in your arms and legs

Leg-raising test

While you are lying flat or sitting, your GP will slowly raise each of your legs one at a time to see if it causes any pain or discomfort in your legs.

This test stretches the nerves in the spine. If there is a disc pressing on a nerve, this stretching can cause pain, numbness or tingling.

Pressure on a nerve

Your GP may test whether there is any pressure on a nerve in your neck by asking you to bend your head forward and to the sides while applying some pressure to the top of your head.

If this causes any pain or numbness to increase, then it is likely a slipped disc is putting pressure on a nerve in your neck.

Further tests

Further tests are not usually required because in most cases the symptoms of a slipped disc settle down within a few weeks.

However, if your symptoms do not ease after four to six weeks, further tests may be required to rule out other conditions and investigate the size and position of the slipped disc.

Some of the tests you may have are described below.

Magnetic resonance imaging (MRI) scan

A magnetic resonance imaging (MRI) scan uses a strong magnetic field and radio waves to produce detailed images of the inside of your body.

MRI scans are effective at showing the position and size of a slipped disc. They can also pinpoint the affected nerves.

Read more about MRI scans.

Computerised tomography (CT) scan

A computerised tomography (CT) scan uses a series of X-rays to scan parts of your body. A computer is then used to build up detailed images of your body.

This produces cross-sectional images of your spinal column and the structures that surround it. Like an MRI scan, a CT scan can pinpoint a slipped disc, although it is often not as effective.

Read more about CT scans.

X-rays

X-rays are not generally used as a test to look for slipped discs as they only see the bones and do not give a view of the nerves and spinal cord.

Other causes

The tests listed above can be used to check that your back pain is not being caused by another health condition, such as:

• a tumour (growth)
• an infection
• arthritis – a painful condition that affects the joints and bones