Spinal Cord Stimulation
If your specialist is talking to you about SCS It is likely you will have had pain for a long time. This therapy requires patients to have had assessment and trialled previous pain therapies including a multidisciplinary pain clinic. There are different types of SCS and your specialist will talk to you about the best one for you. There is evidence that SCS improves patient outcomes more than multiple rounds of spinal surgery.
What is Spinal Cord Stimulation?
A spinal cord stimulator (neurostimulator) is an electrical device positioned near the spine which delivers a pulsed current to the spinal cord which interrupts the pain signals being sent to the brain. The device is implanted under your skin and has a hand held control which allows the patient to change the intensity, within the limits set by the specialist until s/he is getting the desired electrical current to reduce the pain being felt by approx. 50%.
Initially, you will be given a trial procedure with an external SCS for up to two weeks so the patient and specialist can assess the benefit of the SCS before it is implanted. This stage is totally reversible. The SCS implant can then be performed with day surgery which is also reversible if necessary.
When is SCS used?
SCS has been in use for more than 40 years. The types of pain conditions there is high level evidence for include: refractory angina pain, failed back surgery syndrome (FBSS), ischaemic limb pain, complex regional pain syndrome (CRPS). However, SCS is expensive and requires long-term management of the implants so experienced medical specialists clinically assess each individual patient to maximise the best device and patient fit. There are specialised SCS teams who look after patients long-term. The medical follow up is generally less for SCS patients than for patients with usual medical therapies making it cost effective health care over time.
How does it work?
The SCS includes four parts:
- Neurostimulator device (small computer) sits under the skin near the abdomen or chest & regulates the electrical current.
- Electrode which sits near the spine
- Internal wire which connects the computer to the electrode
- Remote control to regulate the strength of the electrical current or turn it on or off.
The low voltage charge generated is felt as a tingling sensation and it is the tingling which "disrupts" the pain signal coming back to your the by sending the "tingles" instead, so it is
tricking or confusing your brain – so the "pain" and the cause of the pain isn't technically gone it's just the perception that's changed.
The electrode will be placed near the spine to stimulate several parts of the spinal cord eg the nerve roots which correspond to the nerves where the pain is being felt eg in the arms or legs. Hopefully, the tingling sensation will then be felt at the pain site, with approx. 50% less pain resulting.
How long does it last?
The SCS battery will need changing after several years which can be performed as day surgery under local anaesthetic.
What are the possible complications?
The SCS procedure is less invasive than surgery and because of this, the complications are reduced. Major complications such as neurological harm are rare and lessened by having the patient conscious and responsive during the procedure. However, there are still risks including wound infection and technical problems, such as the electrode moving from its implant site. Over many years, procedures and devices have greatly improved but risks remain as with other interventional procedures for pain. Patients should also consider that airport security could be activated by the device and MRIs may be difficult to perform with the SCS implanted.
Who does SCS work best for?
Clinical patient selection criteria are applied to each individual. There needs to be an explanation for the pain even if imaging isn't able to verify the cause eg FBSS. Patients will have often attended a multi-disciplinary pain clinic so that recommended psychological and physical therapies have been tried and continue to be used. Patient outcomes are improved when SCS is used in conjunction with active ongoing self-management of pain. Medication may also still be needed but often is reduced.