Invasive treatments for neuropathic pain

Editor’s Note: Dr Mailis-Gagnon will be writing for CARP Action Online on a semi-regular basis. Should you have any questions about pain please write to us at [email protected] We will try to integrate some of your concerns in Dr. Mailis- Gagnon’s future columns.

So far we covered all forms of medicinal and non pharmacological treatments for neuropathic pain. However, there are more treatments that require an “intervention” in the form of needles or surgeries.

The popular name “nerve blocks” is a misnomer as it mostly reflects injections with tender points in muscles. They are used for a variety of soft tissue pain problems (why they are done and how effective they are is beyond the scope of this paper), but soft tissue tender points are found in a minority of neuropathic pain patients. These types of injections have really no good place in the management of neuropathic pain.

However, there are several other injections of drugs in the proximity of nerves or in the spinal cord (the nervous tissue that exists within our “backbone”). Epidural and caudal blocks involve the injection of steroids like prednisone (a strong medication against inflammation) on the surface of the spinal cord (the doctor has to be guided by special equipment so that he/she would know what exactly they inject). Scientific literature supports some of these injections for cases of herniated disc with “sciatica”. These injections are done by specialists (usually doctors trained in anesthesia) and require special equipment.

There are several surgeries that can help certain neuropathic pains. The most common ones are surgeries to the back in an effort to relieve pressure from “pinched” nerves. The decision to undergo such surgery must be carefully considered between a patient and the physician. Back surgeries do not work well if the pain is only centered in the back. There must be good indication that the spinal nerves that run to the legs or the arms are truly compressed. If such surgeries are done without a good reason, they may mean a lot more trouble than good for the patient.

Other forms of surgeries for injured nervous tissue (for example in patients with spinal cord injury, paralysis and severe neuropathic pain or patients with amputation and “phantom limb pain”) are done by neurosurgeons and may require cutting or burning nervous tissues with high frequency currents. Releasing scar tissue and pressure directly from injured nerves, is commonly done in those who have nerve damage after trauma or surgery.

Finally, implantation of devices within the spinal cord or the brain are important advances for the management of certain complex patients with neuropathic pain. Intrathecal pumps (inserted within the spinal cord) serve as little reservoirs for pain medications that are released slowly in the body. Spinal stimulators are implanted on the surface of the spinal cord and send messages to the brain that counteract the pain messages. Deep brain stimulators are used as a last effort to control intractable pains that are resistant to all treatments (like the sever pain after a stroke etc). These devices are quite expensive and in their vast majority they are not covered by provincial health plans and often by private health plans. If you are a resident of the Greater Toronto Area and particularly interested in understanding the availability of these devices and access to all other forms of neuropathic pain management I discussed, please check on to find information about our upcoming Neuropathic Pain forum on November 3, open to the public.