Neurostimulation, more commonly known as spinal cord stimulation (SCS), is a safe and effective therapy that has been used for more than 40 years to control severe, ongoing neuropathic pain. It does so by intercepting pain signals as they run along the spinal transmission system, before they have a chance to reach the brain.
The therapy employs a small device about the size of a stopwatch which is implanted into the body, whose job it is to modulate (modify) the pain messages, thereby replacing the sensation of pain by something much more tolerable (such as a gentle tingling). It does this by delivering its own electrical signals. Patients are afforded a good deal of control over the device, including the ability to turn the current on or off and the ability to adjust the intensity of the signal.
Per a wikipedia entry:
Spinal cord stimulation (SCS), in the simplest form, consists of stimulating electrodes, implanted in the epidural space, an electrical pulse generator, implanted in the lower abdominal area or gluteal region, conducting wires connecting the electrodes to the generator, and the generator remote control. SCS has notable analgesic properties and, at the present, is used mostly in the treatment of failed back surgery syndrome, complex regional pain syndrome and refractory pain due to ischemia.
This particular therapy is especially useful in treating chronic pain of the back, neck, arms, and legs, or in addressing neuropathic pain (pain marked by burning, tingling, or numbness). It is often employed after trying other treatment options, including physical therapy, medications, injections, nerve blocks, or surgery.