Nerve block injections
A nerve block injection, often called ‘perineural injections’, is an injection to help reduce the nerve inflammation and sensitivity that can cause the generation of pain signals within the nerves from a specific area of the body.
These injections typically contain a mixture of local anaesthetic and depot corticosteroids (the type of steroid that reduces inflammation) and work by temporarily reducing or ‘blocking’ pain signals in the nerves being treated.
Nerve block injections can help many, but not all types of pain. They can often be very helpful when diagnostic tests, such as MRI scans, have identified a probable underlying cause of nerve pain that’s likely to respond well to the treatment. In addition, nerve blocks can be very effective in reducing the pain of shingles and post-shingles neuralgia, and can reduce permanent damage to the nerves affected by the shingles if carried out soon enough. Nerve blocks can also be used to help determine the root cause of pain when other tests haven’t been conclusive. If the injection is effective, this can indicate which further treatments may be suitable for longer-term management of the patient’s pain. Symptoms and conditions most typically treated by nerve block injections, include sciatica, back, arm, shoulder and neck pain linked with nerve irritation originating in the spine, sacroiliac and coccyx pain, certain types of facial and jaw pain, plus nerve and joint pain in the hands, knees and feet.
Nerve block injections are usually administered by a specialist consultant in an operating theatre. You’ll be asked to change into a surgical gown and your consultant will talk you through what’s going to happen beforehand. Depending on the area being treated, X-ray or ultrasound will be used to help guide the injection into the correct location, and local anaesthetic is applied first to numb the area. Sometimes, sedation is also used in order to make the procedure more comfortable for you. This will be administered by an anaesthetist and means that, while you won’t be asleep, you’ll be more relaxed.
If sedation was used, you may be groggy afterwards, and this will be monitored briefly before you go home. You won’t be able to drive for at least 24 hours, until the sedative has completely worn off, so you will need somebody to accompany you home. There may be some bruising and soreness at the site of the injection, but this should settle within a few days. In more rare cases, there may be some temporary weakness or floppiness in the limbs linked with the nerves being treated. Your consultant will be able to discuss side-effects with you and how to manage these.
Nerve block treatment is not usually 100% effective, and the results aren’t always immediate. However, many people experience very significant improvements that can last anything from a number of days to many months, during which time, the problem can settle, and be further helped by specialist physiotherapy.