Neuromodulation

Overview

Neuromodulation is defined as an alteration of nerve activity though the delivery of a stimulus, such as electrical stimulation. This type of procedure is utilized for the treatment of a variety of forms of chronic pain. By implanting a thin lead, akin to a headphone wire, that is then attached to a small generator device, electrical impulses are delivered to a nerve or the spinal cord; this stimulation decreases the pain signals delivered to the brain. Nerves can either be targeted centrally (near your spinal cord) or peripherally (nerves outside of the brain and spinal cord). Depending on your diagnosis, lead implantation may be temporary or permanent.

Spinal Cord Stimulation

Spinal cord stimulation involves placing one or two thin leads in the epidural space (space outside the fluid-filled sac that houses your spinal cord) that are connected to a generator placed under the skin near the buttocks. You are provided an external remote with which you can adjust the electrical stimulation delivered. Stimulation intensity can vary from sub-perception (feeling nothing during stimulation) to paresthesia-based (feeling a gentle tingling sensation).

What are the goals of spinal cord stimulation?

The goal of spinal cord stimulation is to improve overall quality of life and to reduce the need for pain medicines. Spinal cord stimulation is generally used in conjunction with other pain management treatments like physical therapy and non-opioid pain medications.

Am I a candidate for a spinal cord stimulator?

Your doctor may consider spinal cord stimulation after conservative pain treatment options have failed to provide sufficient pain relief. Some of the common indications for this therapy include:

• Chronic back pain, including persistent pain after surgery (“failed back surgery syndrome”)
• Complex regional pain syndrome
• Pain after amputation
• Nerve damage, for example after chemotherapy, radiation, or surgery
• Spinal cord injury
• Chronic knee pain

What happens during the procedure?

Spinal cord stimulation requires two procedures: the first to test if the device is right for you and the second to implant the device.

What happens after the procedure?

Most patients are discharged to recover at home after the procedure is complete. Some pain at the surgical site is common for several days after the procedure. You will have surgical dressings over the incision sites and your physician will instruct you on how to care for these. In addition, your physician will give you instructions on which medications may be helpful to manage post-operative pain.

Light activity is usually recommended for approximately two weeks after surgery. Your physician will schedule a close follow-up, typically 1-2 weeks after surgery, to assess your recovery.

What are the risks of this procedure?

Spinal cord stimulator implantation is considered safe, and complications are rare. A small percentage of patients may experience the following: bleeding, infection, dural puncture that results in severe headache, and nerve or spinal cord damage that can be transient or permanent. There is also a risk of device malfunction such as lead fracture, lead migration, and battery failure. Your physician will review these considerations with you in detail at the time of your visit.

Peripheral Nerve Stimulation

Peripheral nerve stimulation involves placing one or two thin leads near a nerve in the periphery (beyond the brain and spinal cord). These leads are connected to a small generator. You will then be provided an external remote with which you can customize the electrical stimulation delivered. Stimulation intensity can vary from a gentle tingling sensation to a more intense tingling sensation.

Peripheral nerve stimulation may be a temporary or permanent treatment. If you and your pain physician select a temporary option, the generator is adhered to the surface of the skin and the leads and generator remain in place for 60 days. If a permanent option is selected, the generator is implanted beneath the skin. Your doctor can provide you with information about which option may be best suited for your condition.

Peripheral nerve stimulation handout for patients (PDF)

What are the goals of peripheral nerve stimulation?

The goal of peripheral nerve stimulation is to improve your function and quality of life. The stimulator aims to alleviate your pain, although pain relief may develop gradually.

Am I a candidate for a peripheral nerve stimulator?

Your doctor may consider peripheral nerve stimulation if you experience or have been diagnosed with:

• Complex regional pain syndrome
• Diabetic peripheral neuropathy
• Ilioinguinal neuralgia
• Intercostal neuralgia
• Lateral femoral cutaneous neuropathy (also known as meralgia paresthetica)
• Nerve injury
• Occipital neuralgia
• Pain after hernia surgery
• Peripheral neuropathy
• Phantom limb pain
• Post-amputation (residual limb) pain
• Post-herpetic neuralgia
• Post-mastectomy pain syndrome
• Post-thoracotomy pain syndrome
• Cancer pain

What happens during the procedure?

This procedure is performed under local anesthesia and generally takes 45 minutes to 1 hour. Under x-ray or ultrasound guidance, your pain physician will insert one or two electrodes at the targeted area near the painful peripheral nerve. Your physician may ask for your feedback during this procedure so that the best position is found for the leads to cover your area of pain.

What happens after the procedure?

This procedure is performed on an outpatient basis and patients are discharged to recover at home after the procedure. After the procedure, you may experience some discomfort at the implant site, which usually subsides. You will be provided wound care instructions and additional materials to perform dressing changes. It is crucial that you follow these instructions closely to prevent complications. Your physician will schedule a follow up with you 1-2 weeks after the procedure to assess your healing and adjust the stimulator settings, if necessary.

What are the risks of this procedure?

Peripheral nerve stimulation is considered safe and complications are rare. A small percentage of patients may experience the following: bleeding, infection, nerve damage that can be transient or permanent, device malfunction such as lead fracture or lead migration. Your physician will review these considerations with you in detail at the time of your visit. 

Dorsal Root Ganglion Stimulation

The dorsal root ganglion is located at the side of the spine, where the spinal nerve root comes out and becomes a peripheral nerve. Dorsal root ganglion stimulator placement is utilized for patients with difficult to treat chronic pain that is not responsive to conversative management. Some indications for this procedure include:

• Complex regional pain syndrome
• Chronic neuropathic pain of the lower extremity (groin, hip, knee, foot)
• Phantom limb pain/pain related to limb amputation
• Inguinal region pain

Placement of leads is very similar to spinal cord stimulation. Implantation begins with a trial, preformed in the outpatient pain clinic. The trial stimulator leads are placed through the skin into the epidural space and positioned near the dorsal root ganglion. You will be able to control the device with an external generator.

At the conclusion of the 7-day trial, the temporary leads will be removed in an outpatient setting. You and your doctor will determine if a permanent device is appropriate for your pain. If so, the second stage of the procedure will be performed in the operating room. Patients are generally discharged to recover at home the same day. Expectations of recovery, risks and benefits are similar to those associated with spinal cord stimulation.