Dr Amit Chakraborty Sep 2018
What is a nerve root block?
A nerve root block is a procedure where a small amount of local anaesthetic and steroids are injected around an inflamed nerve in order to suppress the inflammation and provide symptomatic pain relief.
How is it done?
Deep nerve roots such as cervical or lumbar nerve root blocks are performed under CT guidance. Superficial nerve root blocks can be done safely under ultrasound guidance.
What is involved?
On the day of the procedure, you will be asked a number of safety questions. You will then lie down on the CT scan or ultrasound table. A dedicated targeted small section CT scan will be obtained to determine the landmarks and formulate an approach. If performed under ultrasound guidance, your sonographer will take a few pictures before the doctor comes into the room.
A skin marking will be placed after careful analysis of your images. The skin will then be cleaned using an antiseptic skin cleansing solution. A small dose of local anaesthetic is usually injected at this point. This may cause momentary discomfort or pain.
Whilst inside the CT scanner or on the ultrasound table, a suitable (usually thin) needle is then carefully guided to the vicinity of the affected nerve. Once the doctor is satisfied with the position, he/she will then gently inject a small mixture of steroids and local anaesthetic close to your nerve.
What to expect afterwards?
The procedure is usually painless although a small amount of discomfort may be experienced during the procedure if the needle inadvertently touches the nerve. After the procedure, there is usually a period of numbness due to the local anaesthetic. This lasts between 4-6 hours, after which full recovery of nerve sensations is achieved. Care must be taken during this time to ensure that you do not suffer a fall or any other injury due to temporary loss of function of the affected part.
What of the risks?
The procedure is usually performed under CT/ultrasound guidance which allows optimal visualisation of the nerve as well as the needle placement at all times. Therefore, injury to surrounding organs is very unlikely. However, as with all procedures, there is a small risk of bleeding during or immediately after the procedure. There is a very small chance of nerve damage from the procedure. There is an even smaller chance of other major complications that include stroke or a spinal cord infarct.
Our doctors have gone through rigorous training and strict assessments. We follow very strict safety guidelines to ensure that the procedure is performed as safely as possible. If you have any questions regarding the side effects, please discuss with our doctors on the day.
How effective are these procedures?
In most cases, CT guided steroid injections provide significant long-lasting pain relief. However, every individual processes steroid differently. A small number of people report no improvement in their symptoms from the injections. If you have never received steroid injections before, it will not be possible to accurately predict how effective it will be. However, in most cases, significant symptom relief for a few weeks can be expected from one injection. The effect is usually felt within 48-72 hours and can last for a few weeks.
How many steroid injections can I have in a year?
In a specific body part, generally, 3-4 injections can be performed in a given 12 month period.