What is an epidural injection?
An epidural injection is the insertion of medication into the epidural space around your spinal cord. It temporarily numbs your nerves to give relief from pain or inflammation. Typically, steroids, anaesthetics and anti-inflammatory medications are administered in an epidural injection.
Our pain medicine consultants work as part of a multi-disciplinary team that includes consultant neurosurgeons, orthopaedic surgeons, physiotherapists, psychologists and occupational therapists. Epidural injections can be given at a number of points in your back, depending upon what you are having it for. There are three common methods for delivering steroid into the epidural space:
- Interlaminar – most commonly used in the mid area of your spine. The needle is placed through your lamina and delivers medication to both sides of your spinal column.
- Caudal – steroid medication is placed at the bottom of your spine, through an area known as the sacral hiatus. It is often used for spinal stenosis.
- Transforaminal – newest type of epidural steroid injection. The medication is placed just outside the foramen (opening where the nerve root comes out of your spine) so that it is closer to the area where the nerve root is being pinched. It is often used for herniated discs. It delivers pain relief to just one side of your spine.
Mobile epidurals use a lower dose of pain relief drugs. They are sometimes used in childbirth as they allow you to walk around during labour.
When is an epidural injection recommended?
An epidural injection is one of many methods doctors use to relieve pain. It is often used as part of a wider treatment plan that incorporates other therapies such as physiotherapy exercises.
It can be used:
- during childbirth, including caesareans.
- during and after some types of surgery such as a herniated disk, spinal stenosis, bone spurs, sciatica, and injuries to spinal nerves, vertebrae and surrounding tissues.
- to treat back or leg pain caused by sciatica or a slipped disc.
An epidural injection isn’t suitable for everybody. Your doctor will advise you if it is an option for you.
Epidural steroid injections may also be recommended to help diagnose spine conditions. By placing medication in a precise area and monitoring your response, your doctor will be able to determine what nerves may or may not be involved in causing your symptoms.
What happens during an epidural injection?
An epidural injection for pain relief in childbirth or surgery is given by an anaesthetist, who is a qualified doctor specialising in the administration of anaesthetics. It is usually delivered in a matter of minutes whilst you are awake, but for some surgeries it is given while you are under general anaesthetic. An intravenous (IV) line is placed in your arm to give you fluids during the epidural. Your doctor will identify where the injection should be given and will inject a local anaesthetic to help numb this area.
An epidural needle is used to insert a small plastic tube called an epidural catheter between the bones of your back. The needle is removed and the catheter is left in your back. This may be a little uncomfortable.
Pain relief drugs are then slowly given through the catheter. They may make your chest, stomach and legs numb, and your legs weaker than normal. They usually take 20 to 30 minutes to take full effect. These drugs can be topped up using the catheter. During childbirth this may be for several hours or after major surgery it may be for a few days.
An epidural injection to treat leg or back pain, may be administered under x-ray or CT imaging guidance to direct the epidural needle into exactly the right position. The steroid will take 24 to 36 hours to take effect.
Benefits of an epidural injection
An epidural injection offers you short term pain relief, either for childbirth, during or after surgery or to treat a health condition such as a herniated disc.
It’s important to be aware of possible complications when deciding whether or not to have an epidural injection. Your doctor will discuss these with you. They may include:
- A headache
- An infection
- An allergic reaction
- Nerve damage.
After epidural injection
After an epidural injection you will be advised to stay sitting or lying down until the drugs wear off. Your legs may feel numb and your skin tingly, which usually lasts for a few hours when the effects start to wear off.
If you are having an epidural injection to treat back or leg pain then the local anaesthetic will last only for a few hours and your pain may return before the steroid medication becomes effective after 24 to 36 hours.
You must arrange for someone to drive you home after an epidural injection.
How long will the pain relief last?
The pain relief you may get from an epidural injection are individual to each patient. It may last for the duration of childbirth, or between three and twelve months for pain relief for lower back and leg pain. An epidural injection is not a cure for your pain.