Spinal Cord Stimulation
Spinal
cord stimulation (SCS) is a procedure that uses
an electrical current to treat chronic pain. A small pulse generator,
implanted in the back, sends electrical pulses to the spinal
cord. These pulses interfere with the nerve impulses that make
you feel pain.
Implanting
the stimulator is typically done using a local anesthetic and
a sedative. Your doctor usually will first insert a trial stimulator
through the skin (percutaneously) to give the treatment a trial
run. (A percutaneous stimulator tends to move from its original
location, so it is considered temporary.) If the trial is successful,
your doctor can implant a more permanent stimulator. The stimulator
itself is implanted under the skin of the belly (abdomen), and
the small coated wires (leads) are inserted under the skin to
the point where they are inserted into the spinal canal. This
placement in the abdomen is a more stable, effective location.
Most stimulator batteries must be replaced every 2 to 5 years.
After
this outpatient procedure is complete, you and your doctor determine
the best pulse strength. You are then told how to use the stimulator
at home. A typical schedule for spinal cord stimulation is to
use it for 1 or 2 hours, 3 or 4 times a day.
When in use, the spinal cord stimulator creates a tingling feeling,
rather than the pain you have felt in the past.
What
To Expect After Treatment
You will have a small incision that you should keep clean and
dry until it heals.
Why
It Is Done
This treatment may be done for people with severe, chronic pain
who have:
• Had a failed spinal surgery.
• Severe nerve-related pain
or numbness.
• Chronic pain syndromes,
such as reflex sympathetic dystrophy.
• Spinal cord stimulation
is typically considered investigational for various other conditions,
including multiple sclerosis, paraplegia, and intractable angina.
How
Well It Works
Some researchers have reported that more than half of people
receiving spinal cord stimulation for failed-back surgery syndrome,
peripheral neuropathy, or phantom limb pain have pain reduction
or relief.1 Spinal cord stimulation seems to work better for
people who have reflex sympathetic dystrophy or postherpetic
neuralgia.
But
there is still not strong proof that spinal cord stimulation
works. Better research is needed. Treatment success varies widely
and is influenced by the cause of pain. Also, if there has been
a previous back surgery, treatment success is affected by the
amount of time that has passed since the first surgery on the
affected area. The more time that has passed since a first surgery,
the less likely spinal cord stimulation is to overcome the pain
signals that have developed over time.
One
long-term study suggests that conditions that are most likely
to have long-term benefit from spinal cord stimulation are failed
back syndrome (pain that spreads or that continues after surgery),
reflex sympathetic dystrophy, multiple sclerosis, peripheral
arterial disease, and peripheral neuropathy.2
Initial
pain relief is often followed by a gradual decline in effectiveness,
apparently caused by the body's increasing tolerance to the
treatment.