Facet joint denervation

What are the facet joints and medial branch nerves?

Facet joints are small joints located in your neck and back that connect the bones of your spine in pairs. They provide stability and allow the spine to bend and twist. Medial branch nerves are small nerves connected to the facet joints that carry pain signals from these joints to the brain.

What are facet joint injections and medial branch blocks?

Facet joint injections involve injecting a local anaesthetic (to numb pain) and a steroid (to reduce inflammation) directly into the joint space. A medial branch block is a similar procedure that targets the medial branch nerves, which connect the facet joints to the brain and transmit pain signals.

Purpose of Facet Joint Injections and Medial Branch Blocks

The injection of anaesthetic and steroids is intended to temporarily stop pain signals. These procedures help determine if your pain is caused by your facet joints. If the injections alleviate your pain, it indicates that the facet joints are the source. The results, whether positive or negative, guide future treatment options.

If a medial branch block significantly reduces pain, a longer-term treatment option called Facet Joint Rhizolysis may be considered. Successful facet joint injections or medial branch blocks can help reduce pain, allowing you to undertake physiotherapy and rehabilitation more effectively.

What happens before the procedure?

Before being referred for a facet joint injection or medial branch block, you will be assessed by a specialist consultant or practitioner. They will take a full history of your symptoms and perform a thorough physical examination. Imaging of the affected area of your spine, such as an X-ray, CT, or MRI scan, may be required to determine the underlying cause of your back pain, such as osteoarthritis.

How do I prepare for my procedure?

Inform us if you take blood-thinning medication when arranging your appointment, as some need to be temporarily withheld beforehand. Common blood-thinning medications include antiplatelets (aspirin or clopidogrel) and anticoagulants (warfarin, apixaban, dabigatran, or rivaroxaban).

Do not stop any medication before consulting us.

Diabetics should closely monitor their blood sugar levels before and after the procedure, as the steroid medication in the injection can affect this for several days.

Arrange for someone to bring you to the hospital and drive you home after the procedure. Ideally, someone should stay with you for 24 hours after your appointment.

Do not drive for 24 hours following the procedure.

What happens during the procedure?

Facet joint injections and medial branch blocks are performed in the hospital as an outpatient procedure under local anaesthetic, and you will go home the same day. Sedation or general anaesthetic is not required.

An experienced specialist Radiologist will carry out the procedure in a room with a special X-ray camera called fluoroscopy. The injections take a short time, but the entire procedure may take up to 30 minutes.

The skin of the affected area will be injected with local anaesthetic to numb any pain. The consultant will then guide the needle to the correct position with the help of live X-ray images. Once in position, the consultant will inject the mix of local anaesthetic and steroid into the joint or, in the case of a medial branch block, into the nerves in your facet joints. The needle will then be removed.

This process may be repeated depending on how many joints are being treated during the procedure. You will usually be able to go home half an hour after the procedure is finished.

What are the side effects of the procedure?

The most common side effect is the slight tenderness and/or bruising at the site of the injection however this will resolve over the first few days. In some cases, you may feel increased pain for a few days after the injection however this should settle.

More serious side effects are rare but can include bleeding, infection, nerve injury and allergic reactions to the medications used in the procedure. It is important to seek medical help if you are feeling unwell.

Recovery after the procedure.

The procedures usually take two to three days to have an effect and typically peaks at one to two weeks. The success of the procedure in reducing your pain and for what length of time varies from one individual to another.