Spinal Cord Stimulator Trials
Who is considered a candidate for spinal cord stimulation?
A general condition known as failed back surgery syndrome is one of the most common reasons spinal cord stimulation is used. The term describes chronic pain after one or more back or neck surgeries fails to alleviate persistent low back pain, leg pain (sciatica or lumbar radiculopathy) or arm pain (cervical radiculopathy).
The therapy also has the potential to alleviate pain related to the following conditions:
- Chronic back pain with or without leg pain
- Peripheral neuropathy, a constant burning pain of the legs caused by the most distant nerves dying off
- Complex regional pain syndrome (reflex sympathetic dystrophy), a progressive disease of the nervous system in which patients feel constant burning pain
What is the spinal cord stimulation trial?
A person considered a good candidate for spinal cord stimulation therapy is usually scheduled for a trial run, which involves insertion of thin wires with electrodes attached.
The trial period is like long-term therapy, except that the device transmitting current is not implanted in the body. Instead, just the wires are inserted, and an external transmitter sends electrical pulses to the electrical contacts near the spinal cord.
During the trial, which takes five to seven days on average, the patient is likely to be asked to note the level of pain relief in different situations during the day and night.
How is the procedure performed?
The trial period procedure is usually performed in a doctor’s office or a surgical center. Procedures vary somewhat with the stimulation device used, but these are the typical steps.
- Local anesthesia is applied to the injection site.
- Guided by fluoroscopy (a type of X-ray), the doctor inserts a hollow needle into the area around the spinal canal called the epidural space. The needle contains thin, insulated wires, called leads, with electrical contacts attached. In some cases, a small incision may be needed to insert the needle.
- The patient is awake in order to provide feedback on the specific areas where pain is relieved by the stimulation, and where pain relief is still required. Each electrode affects pain in a different area, so doctor-patient communication is crucial in making sure the doctor has adjusted the location of the electrical contacts to cover all the areas in pain.
- The leads are connected to an exterior pulse transmitter that the patient wears on a belt. The wire connecting to the external neurostimulator is taped to the person’s back during the trial to hold it in place.
- The patient is given time to recover from the procedure before going home.
- A hand-held controller to adjust the amount of stimulation is programmed by the doctor based on the earlier feedback from the patient during adjustment of the electrical contacts.
- The patient is given the controller and can turn it on to send pulses of current to the electrodes as needed. The controller offers a range of adjustments in the intensity and duration of stimulation. With some models, adjustments are needed for significant body movements, such as getting up or lying down.
- The doctor may ask the patient to track which stimulation settings are used at different times and how well the pain was relieved. If the pain is not relieved, the doctor should be contacted right away so the device can be reprogrammed.
The site on the back where the leads and electrodes were inserted is usually uncomfortable for a few days. Any significant local pain should be reported to the doctor.