Dorsal Root Ganglion (DRG) Stimulation

Dorsal Root Ganglion Stimulation (DRG) is similar to Spinal cord stimulation (SCS) in many ways. SCS systems have been in use for more than 30 years to treat chronic pain. SCS works by delivering electrical impulses in the region of the spinal cord and interrupt pain signals to the brain. SCS has been used to treat a wide range of chronic pain conditions, such as failed back syndrome, neuropathic (nerve) pain and complex regional pain syndrome. 

Dorsal root ganglion stimulation is designed to work on similar principles to the above. The electrical impulse is more focussed as the electrical lead is positioned over the dorsal root ganglion (an area specific to a single nerve as it leaves the spine).

It is aimed at targeting a very specific focal area of your pain, e.g. scar site pain. DRG stimulation might not cover large areas of pain. 

Dorsal root ganglion stimulator is developed and marketed by Abbott. 

It is important to understand that dorsal root ganglion stimulation is not a cure for your pain, but it may help you to manage your pain more effectively and improve your function. 

The procedure is new to UCLH as of 2018.

You may experience improvement in your pain symptoms and quality of life. You may feel more able to function and participate in activities of daily living. It may also be possible for you to take less pain medication.

Interventional Pain procedures have associated risks. Risks associated with DRG stimulation can be grouped into common, less common and very rare. 

It is common to feel some minor discomfort after the procedure which may require a short course of pain killers.

Less common risks include:

• Pain at the site of surgery and implant. In majority of the patient this is not severe. In 7 to 10% patients this can be severe. In a small proportion of these patients further surgery or removal of the system may be advised. 
• The risk of Infection is about 3 to 5 %. This will require treatment with antibiotics and might warrant removal of DRG system. 
• Bleeding: This may lead to bruising, and in rare cases may require further surgery. 
• Headache (1%): It is possible that the membrane around the spinal cord could be accidentally punctured during the procedure. This causes a leak of cerebrospinal fluid which can result in severe headaches.  These headaches generally get better once the leak is sealed but you may require further treatment for this. 
• The leads may move, break, or stop working. This may require another operation to replace the lead. 
• You may feel stimulation outside the area of pain, but this is only a problem if you find it unpleasant. 
• Failure to block pain from the area affected, which may lead to consideration of further surgery to re-site the leads or remove the system. 

There are other problems which are very rare but more serious. These include: 

• Needle damage to the spinal cord or nerves. 
• Bleeding and compression of the spinal cord. This can result in nerve damage which may be permanent and would be very difficult to treat effectively. 

Not everyone responds to DRG in the same way and your experience may vary. 

It is important to understand that dorsal root ganglion stimulation is not a cure for your pain, but it may help you to manage your pain more effectively and improve your function. 

Safety and Precautions 

Once you have a stimulator device implanted there are some things you should know about that may affect the device. 

You should always carry an ID card that will be provided by the hospital. 

Some types of scanners can interfere with your spinal cord stimulator. 

Normal x-rays and CT (computerised tomography) scans are generally safe, but there are specialist requirements for an MRI scan and not all systems will be suitable for MRI scans. For this reason, we suggest that either the manufacturer or pain management team are contacted to advise the radiology team if an MRI is planned. 

Other scanners in airports and in some shops can also change the settings of a dorsal root ganglion stimulator. In general, any sign that gives a warning for people with heart pacemakers also applies to people with spinal cord stimulators. 

If surgery for any reason is required once you have a stimulator device inserted, the surgical team must be advised of your stimulator. Certain equipment cannot be used such as monopolar diathermy (an electrical device used by surgeons to stop bleeding during an operation). This will be explained during the Pain Management Programme that we will organise for you. However, simply, if you need an operation the surgical Team should know they can only use bipolar diathermy and they need to contact the Pain Team or manufacturer if the need further advice. You will be given a card with this information.

Short-wave diathermy

Some health care professionals, such as physiotherapists, use a treatment called ‘short-wave diathermy’. This treatment can be dangerous for people who have a dorsal root ganglion stimulator. 

If at any time you develop a problem with your dorsal root ganglion stimulator or have any concerns, you should contact the pain management centre.

The decision to go ahead with this treatment is entirely yours. If you choose not to proceed, we will discuss other treatment options and the management of your symptoms with your doctor. Your decision not to proceed with DRG will not affect your further treatment in any way.

DRG is usually reserved for patients who have severe chronic pain in a specific area that is limiting their daily activity and who have already tried all reasonable and more conservative therapies. 

The pain management centre offers a number of different treatments which include a variety of injections, psychological approaches, physiotherapy, TENS (transcutaneous electronic nerve stimulation), medicines and acupuncture. 

We are happy to discuss your options in detail to help you choose the best treatment for you.

If you and your pain doctor decide that this is the right treatment option for your pain they will enter you onto a care pathway, this includes further assessments, potentially investigations and most importantly further education with opportunity to ask questions and discuss your treatment. 

You will first be seen by a medical doctor who will determine whether your pain is suitable for dorsal root ganglion stimulation. Once you have decided you would like to have this treatment you will be entered into an implant programme.

Implant programme

The programme is designed to: 

• Provide you with information on the procedure and potential risks and benefits 
• Increase your understanding of chronic pain and dorsal root ganglion stimulation 
• Increase the effectiveness of dorsal root ganglion stimulation treatment 
• Work on maximising your physical fitness and function 
• Help you to work to realistic goals 
• Maximise psychological well being 
• Introduce you to other patients who have similar experiences 
• Provide support in decision making 
• Give you the opportunity to learn about the components of the system and what they look like. 

Once you have completed the implant programme you will be put on the waiting list for the procedure, and you will be contacted when a date becomes available. You will then also be assessed by the Pre – operative Assessment Centre team prior to coming into hospital to prepare you for the procedure.

To prepare for the procedure

You may be asked to stop any blood thinning medication such as warfarin, aspirin and clopidogrel. The pain management nursing team will advise you of alternatives to these medications in the event that you need to continue with these treatments. Please do not stop any medications until you have been advised how and when to do so. 

You will need to fast before this procedure. You should not eat for at least six hours and have nothing to drink for up to two hours beforehand. As this procedure is usually a day case admission you will be asked to bring someone with you to make sure you get home safely. Alternatively, you may be admitted into hospital for a stay of one night, but you will be advised prior to admission if this is likely to be required.

We want to involve you in all decisions about your care and treatment. If you decide to go ahead with this procedure, by law we must ask for your consent and will ask you to sign a consent form. 

This confirms that you agree to have the procedure and understand what it involves. Staff will explain all the risks, benefits and alternatives before they ask you to sign a consent form. If you are unsure about any aspect of your proposed treatment, please don’t hesitate to speak to a senior member of staff again.

The dorsal root ganglion stimulator system will be implanted in an operating theatre using x-ray guidance. You will be awake during the procedure which is performed under sedation and with a local anaesthetic. A small incision will be made in your back to implant the lead under your skin, siting the lead over the appropriate dorsal root. Another incision will be made in either your abdomen or buttock depending on which site you choose for your battery to be implanted. The battery will be positioned under your skin. 

After the procedure you will spend a short time in the recovery room before going back to your ward. 

When you are fully awake a specialist pain nurse will teach you how to switch your stimulator on and off. The nurse can also use a computer to programme your DRG to deliver the stimulation to the right area of pain. When you are fully recovered you will be allowed to go home. Most patients will be able to go home on the day of the procedure. 

If the procedure is scheduled for the afternoon, you may be required to stay in hospital overnight, but you will be advised prior to admission if this is likely to be required.

When you get home after the procedure you should rest for the day. Do not attempt to drive or go to work. You should aim to limit the amount of bending and twisting you do. This will reduce the risk of the lead moving out of place. 

It usually takes up to three to six weeks for the lead to be fully secure, but you will be able to move around freely as long as you are careful not to bend to pick things up or turn or twist your back. You should also avoid heavy lifting. 

Any suture or clips can usually be removed 10-14 days following the surgery. This can be done by your GP or practice nurse. 

If you notice any redness or swelling around the wound site or near to the implant you will need to act as soon as possible. 

This is because you may require further assessment and in some cases a course of antibiotics if an infection is present. 

Should your GP not be available you should visit your local accident and emergency (A&E) department. In case of suspected infection, we would expect a wound swab is carried out at the time of antibiotic prescription. 

If your stimulator stops working or you require advice concerning the stimulator, you can contact one of the specialist nurses who will see you in normal working hours. 

We will also ask you to complete a diary and some questionnaires, in order to assess your progress. 

Ongoing care

You will be seen by a specialist nurse in clinic six weeks after the insertion of your stimulator. The first appointment will be to check the wounds have healed and that the spinal cord stimulator is working at an optimal level. 

Regular follow-up is necessary to ensure that the dorsal root ganglion stimulation continues to work effectively and also to measure the battery life. 

You will also attend the group sessions at three months, six months and 12 months. 

You will need to see your GP first and then contact the Pain Management Centre - our working hours are Monday to Friday, 9am to 5pm. 

UCLH is a teaching Trust, and you may be asked if medical or nursing students can observe or assist with your care. 

We are also a major centre for medical research and conduct service audits in line with local and national guidelines. If you are interested in taking part in research projects, ask the person who is caring for you. 

If you do not wish to take part in teaching of students and/or research, please tell us when you arrive. Not taking part in teaching or research will not harm your care.

British Pain Society 

Information about spinal cord stimulation for the management of pain: recommendations for best clinical practice. www.britishpainsociety.org 

UCL Hospitals does not accept responsibility for information provided by other organisations 

www.britishpainsociety.org

https://www.nice.org.uk/Guidance/TA159 

Deer et al, Dorsal root ganglion stimulation yielded higher treatment success rate for complex regional pain syndrome and causalgia at 3 and 12 months: a randomized comparative trial, Pain, volume 158, number 4, pp 669-681, 2017.

Pain Management Centre 

National Hospital for Neurology and Neurosurgery at Cleveland Street, 25 Cleveland Street, London, W1T 4AJ 

Reception: 020 3448 4776 

Fax: 020 3448 3511 

Email: painmanagement@uclh.nhs.uk 

New patient appointment enquiries: 020 3448 4777 

Switchboard: 0845 155 5000 / 020 3456 7890

Website: www.uclh.nhs.uk/painmanagement