The spine is made up of bones (vertebrae) joined together by the discs at the front and small joints called facet joints at the back. Strong ligaments and muscles stabilize the spine. The spinal cord and nerves are contained within the spine and at each level a nerve root comes out to supply different parts of the body.
For a variety of reasons one or more levels of the spine can degenerate causing back pain and sometimes instability.
Nerves within the spine can also become irritated or compressed as part of the degenerative process. Nerve pain can occur and is usually felt along the path of the nerve, which varies depending on which nerve root is effected. Nerve pain is often very difficult to control with pain killers.
Sometimes the nerve does not function resulting in weakness and numbness. Rarely bowel and bladder function can be effected. If such neurological symptoms are experienced they should be reported immediately as they may require emergency treatment.
If surgery is to be undertaken, it is clearly essential to identify as accurately as possible the source of the pain. Often this is obvious on the scans and X-rays but sometimes more than one potential cause is found or the cause is not entirely clear. In such situations further more invasive investigations can be helpful.
Nerve root injection involves the insertion of a needle into the nerve canal using X-ray control. Contrast is injected to confirm correct positioning and so that the nerve can be "provoked". If provocation reproduces the pain at any particular root it suggests that this is a source at least in part of your symptoms.
Local anaesthetic can be injected to see if the pain resolves which offers further evidence of the disc being the pain source.
Sedation is given during needle placement and then you are woken up, as it is essential that you are fully cooperative during the injection. The injection may cause some discomfort or pain but this is usually short lived.
After the operation you will be encouraged to mobilize as soon as possible with the assistance of physiotherapists and nurses. Once mobile enough to manage at home you can be discharged.
It is important to keep a record as to whether your pain is worse, the same, or better in the hours and days after your root injection.
An outpatient appointment will be arranged.
Nerve root injection is a test rather than a treatment for your symptoms. You should get back to normal function very quickly after the procedure. The procedure is usually done as a day case.
In order to monitor the results of surgery you will be asked to complete outcome questionnaires from time to time.
Most patients do not suffer any adverse problems. Occasionally complications do occur and can require further treatment.
Nerve damage is rare during root injection. If it occurs it can cause areas of numbness, pins and needles and weakness. Neuralgic pain can also be troublesome.
Corda equina syndrome is very rare and occurs when the nerves to the bowel and bladder are effected. Any numbness around the bottom or problems with passing stool or water should be reported immediately.
Scar tissue can form around the nerve root tethering the nerve causing on going pain. Occasionally further surgery is required to free up the nerve.
Infections can occur and these can be treated with antibiotics but rarely require surgical cleaning and debridement.
Damage to the lining of the nerve root (Dura) can result in a leak of fluid (csf).. Rarely the leak persists and has to be repaired surgically.
Spasm can occur causing a short period of troublesome pain aggravating previous symptoms. This is treated if necessary by antispasmodic medication.
Spinal anaesthesia can be induced if lacal anaesthetic gets inside the dura which can cause temporary weakess and numbness in the legs.
Anaesthetic complications will be explained by your anaesthetist.
Please be assured that every effort is made to avoid the complications listed and any others which can very rarely occur.
If you have any questions or wish to discuss things further please ask at any time. It is important that you have all the information you require and we will assist you in every way possible.
MR ANDREW HOWARD
Consultant Spinal and Orthopaedic Surgeon
Ref No NRI0205