Foraminal Epidurals

Foraminal Epidurals 2021-01-16T12:00:47+00:00

Foraminal epidurals can also be called a selective nerve root injections (and also called nerve root blocks) are used as a both a treatment and as a diagnotistic tool. The steroid part of the injection helps to reduce pain and inflammation around the spinal nerves.  The local anaesthetic part of the injection serves as the diagnostic tool and helps to confirm, or exclude, which nerve root the pain is originating from to allow planning of approriate further treatment.

Mr Hilton performs all spinal injections in theatre and under X-ray guidance. He will also give you the choice of having the procedure performed under sedation or local anaesthetic.

As a treatment, nerve root injections may be used to relieve leg or arm pain which is produced by irriatation/pressure on a nerve root, usually caused by a disc prolapse, but may be due to bone compressing the nerve or other rare causes. Nerve root injections have relatively few risks and complications (see below) and are minimally invasive way of treating spinal nerve pain.

 One question that is always asked: How long will it last?

The answer is, everyone is different; for some people the pain relief from a nerve root injection can last many months or years but for others, the benefit may only last a a few weeks or even a few hours.

If the benefit is only short-lived or you gain no benefit at all at anytime, it maybe very disappointing but do not worry; it has not failed because it has been very useful diagnostically to help determine which area of the spine is causing the problem. This is extremely useful when surgery is being considered.

Likewise, you may gain no benefit at all, not even for the few hours immediately after the injection. Again, this can be disappointing. It has not “failed”, instead it strongly suggests that the pain is not originating from that nerve root or level in the spine. This is diagnostically very important and further investigations are needed to establish exactly where the pain is originating from.

After you have had the procedure, it is very helpful if you can keep a note as to how your symptoms change especially in the first few hours after the injection and over the next few days.


Questions to ask yourself are:

1) Has the procedure taken my leg pain away? For example, has it taken 100%, 75% or 50% of the pain away? Or, how much of of the pain is left?

2) If you have back pain as well, does it take your back pain away?

3) Does your mobility or walking distances improve?

4) If you also have reduced sensation or pins and needles, does the injections relieve them?

5) What symptoms are still left?

Bring your answers with you to your follow-up appointment.


How long your recovery takes mainly depends on whether you have been sedated or not.

 Following the injection you will be taken into the recovery suite where you will monitored until it is safe for you to return to the ward. You will discharged home when comfortable on the day of the procedure.

Following epidurals patients should not drive for 24 hours. You should return to normal activity as you feel comfortable and start physiotherapy as soon as possible.

How is a Nerve Root Injection Performed?

Cervical Nerve Root Injections

All spinal injections are performed in theatre under X-ray guidance. Patients lie on their back on the operating table with their head on a head ring. The image intensifier is used to guide a special needle into position around the affected nerve root. Once the needle is in the correct position a special dye is injected, which can be seen on the X-ray,  to confirm the position and then the local anaesthetic and steroid is injected around the nerve root.

Lumbar Nerve Root Injections

Mr Hilton performs all nerve root injections under X-ray guidance to guarantee the injection is in exactly the right place. Patients are taken into the operating suite; some elect to have the procedure under sedation and other choose to have it under local anaesthetic. Either way, patients have the procedure lying on their front on the operating table. The image intensifier is used to guide a special needle into the correct position around the affected nerve root and then a special dye is injected to confirm the correct position on the X-ray before the local anaesthetic and steroid is injected around the nerve root.

Risks and Complications of Nerve Root Injections

(about 1 in 5000)

Infection, bleeding, DVT/PE, facial flushing, allergic reaction, CSF leak, nerve damage, CVA (stroke), recurrence or failure to relieve symptoms.

Occasionally, after the nerve root injection, patients experience temporary decreased sensation or numbness in the arms, legs or perineum. Do not be alarmed this is due to local anaesthetic and will usually recover in 6 – 8 hours.