What is spinal cord stimulation?
Which pain conditions can spinal cord stimulation help ?
- Persisting back and leg pain after spinal surgery (commonest reason)
- Nerve pain after injury in surgery or other trauma in a limb or the trunk
- Nerve pain from damage caused by metabolic, infective, inflammatory and other causes. This includes diabetic neuropathy and post herpetic neuralgia (persisting pain after shingles)
- Complex Regional Pain Syndrome
- Severe headache conditions
- Limb pains due to lack of blood flow (vascular insufficiency)
- Persisting severe angina
- Some pelvic pains
- Some abdominal pains
Which pain conditions does spinal cord stimulation not help ?
Spinal cord stimulation does not relieve pain that involves inflammation pain and “mechanical” pain. So it does not help with arthritis pain (osteoarthritis, rheumatoid arthritis, gout etc), or pains due to “wear and tear” of joints, muscles, tendons and ligaments.
Spinal cord stimulation does not help very widespread pain – so it does not help in fibromyalgia, or when people have back pain after surgery but also have other severe widespread pains from arthritis in multiple joints.
Are there reasons why someone may not be suitable for spinal cord stimulation ?
Yes, there are reasons that spinal cord stimulation may not be a wise option:
- Pain problem not likely to respond to SCS (see above)
- Technically not possible – eg access not possible due to past surgery or advanced spinal degenerative changes
- Active infection in the body
- Immunocompromised and at high risk of infection
- High risk of bleeding (bleeding disorder, or on anticoagulants that are high risk to stop)
- Poorly controlled medical condition(s) eg, diabetes
- Awaiting other surgeries or investigations
- Very obese (increase risk of complications and technical problems with implantation and weight should be addressed first as a health issue)
- Very underweight (high risk of discomfort and pain with implanted system due to lack of “padding” )
- High danger of wound breakdown or pressure sores
- Active psychological illness that requires further attention, including major active psychological and social stress.
- Unable to safely be educated on SCS, remember important points, and follow guidance
- Follow -up availability uncertain
What do you feel with spinal cord stimulation?
With most of stimulation patterns now used, people do not feel the stimulation at all. With some stimulation patterns people feel tingling or pins and needles type sensations. When testing of the system is done, people may briefly feel strong stimulation – but this will not be used as therapy.
How much pain relief does spinal cord stimulation give?
Everybody is different and every pain is different. Some people will find they get 80 to 100% relief of their pain. Others will find it doesn’t ease their pain at all. This is why a “trial” of spinal cord stimulation is done. The trial allows people to see what pain relief they get with the therapy.
Can spinal cord stimulation treat numbness and restore normal feeling?
Spinal cord stimulation does not restore feeling to numb areas.
Can spinal cord stimulation treat weakness and restore power and strength?
Spinal cord stimulation does not directly boost muscle power or strength. Power, strength and flexibility need to be worked on in their own right with activity and exercises.
How long has spinal cord stimulation been around?
Spinal cord stimulation was first performed in 1967. For the first 40 years SCS almost always used tingling “paraesthesia” sort of stimulation that people felt. In the last 10 years, a number of new forms of stimulation have become available that influence pain pathways but are not felt. These are known as “paraesthesia-free” stimulation modalities.
What are the risks of spinal cord stimulation?
Why do you ask some people to reduce their pain medicines before trying spinal cord stimulation?
Many people with severe chronic pain find themselves taking high doses of pain medicines, but still feeling severe pain. So the pain medicines are not being very helpful. In some cases, the medicines may be making the pain worse. Strong opioid drugs in high doses ( examples are morphine, oxycodone and fentanyl ) can actually very slowly turn up the pain amplifier centrally when they are taken long term. So they make pain worse. They can also have other negative effects – supressing the immune system, interfering with hormones, and sedation are all of concern. Some other pain medicines may interfere with the response to spinal cord stimulation. To give people the best chance of pain relief and the best chance of good long-term outcomes with spinal cord stimulation, we sometimes need to ask people to reduce these medications.
What is the difference between a rechargeable system and a non-rechargeable system?
Some patterns of stimulation use very small amounts of energy and an IPG can be implanted that will last for years without recharging. This is known as a non-rechargable system. When the battery eventually runs out, the IPG will need replacing.
Most SCS systems inserted for pain relief use rechargeable systems because they allow more energy intensive stimulation patterns to be used. Rechargeable systems require people to sit quietly with recharging devices placed over the IPG for 30 to 45 mins at a time. This could be daily or every few days, depending on the stimulation pattern used.
How long does a spinal cord stimulation system IPG battery last?
Non-rechargeable IPG’s are generally only implanted when it is anticipated that the battery will last 3 to 7 years. Sometimes energy use is more than expected and they need replacing earlier than this. Rechargeable IPG’s are generally expected to last for 10 years or more.
Which spinal cord stimulator system is best?
This is bit like asking which car is best. Different SCS systems have advantages and disadvantages for each individual patient. Dr Smith uses several different systems and remains at the forefront of new developments. He will advise you on the options best suited to you.
Why does Dr Smith ask spinal cord stimulation patients to see a pain psychologist?
Severe, chronic pain has massive impacts on peoples’ lives. Many people can feel anxious, depressed, and angry. Sleep and activity are disrupted. The pain affects work, relationships and future plans. Many people have lost confidence in many areas. Even successful pain reduction with spinal cord stimulation does not automatically untangle all of these problems. Pain psychologists can help people assess these areas and offer guidance where appropriate. It is also important that people are able to understand and cope with a spinal cord stimulation trial, including coping with a unsuccessful outcome should this happen. Pain psychologists help assess peoples’ preparedness for a trial. NICE guidelines on Spinal Cord Stimulation stress the importance of this multidisciplinary approach. https://www.nice.org.uk/guidance/ta159/chapter/1-Guidance
Can I have an MRI?
MRI’s use strong magnetic fields. Magnetic fields can damage some older SCS systems and there can be a danger that the SCS system heats up and causes burns. Most new systems have been made to allow MRI’s (this is known as being MRI compatible), but this is still “conditional”. Even the latest MRI compatible SCS system needs checking before an MRI can proceed, and the MRI department needs to know about the MRI in advance so they can adjust their imaging protocols.
Does electrical equipment interfere with SCS?
All electrical equipment and phones produce small electrical fields around them. Mostly, these will be too weak to affect an implanted SCS system. However, it is recommended to keep distance from strong electrical fields. If distance cannot be maintained then the SCS device should be turned off.
- Security screening devices such as in in airport and shop entrances: It is recommended that you ask to bypass the screener. If you are required to go through screening then turn off the stimulator and move through the centre of the screener quickly
- Tag deactivators, such as those found in retail stores and libraries: keep distant
- Large power lines or power generators: keep distant, turn off device if distance cannot be maintained
- Electric steel furnaces and arc welders: keep distant
- Large, magnetized stereo speakers: keep distant
Do phones interfere with SCS?
Mobile phones are not likely to cause problems.
What precautions do I need to take with SCS and other medical devices or procedures?