Neuromodulation therapy through implantable spinal cord stimulation (SCS) devices can be an effective treatment option for patients with chronic pain related to refractory trigeminal neuralgia (TN) and diabetic peripheral neuropathy (DPN). Some preliminary findings indicate that SCS can reduce pain related to refractory TN by up to 50%. For DPN, a 2021 pivotal study found that 79% of patients treated with spinal cord stimulation reduced pain by at least 50%, leading to FDA approval of SCS devices to treat the condition. 

“These are promising options for patients who have not had success with standard treatments,” says neurosurgeon and spine specialist Nandan Lad, MD.

Building neuromodulation programs for TN and DPN takes a collaborative approach, with neurologists, neurosurgeons, and other specialists from podiatry to endocrinology all working closely to identify the patients who will benefit most and deliver the best possible results. “We’re growing our multidisciplinary team’s capabilities to offer effective treatments to more patients,” says Lad.

The first-line treatments for TN are typically carbamazepine and oxcarbazepine. For patients who do initially respond, many need to stop treatment due to side effects or resistance over time. This leaves a significant percentage of patients with persistent paroxysmal pain. 

“Neurologists may reach a point where patients aren’t experiencing relief with the standard of care or previous procedures, and we want them to know that we may be able to offer effective surgical options,” says Lad. “We have a great partnership between neurology and neurosurgery at Duke to streamline our care with a designated navigator who helps patients coordinate and schedule appointments with multiple specialists.” 

One of the benefits of SCS is that it can be tested with a trial, so patients know if it would be beneficial to continue with the permanent device. Lad explains, “With a needle-based procedure, we guide a small wire under X-ray into the epidural space of the cervical spine and connect it to an external battery. The patient then tries it for a week to test if it reduces their facial pain. If the patient reports at least a 50% pain reduction, we offer the permanent device.”

The permanent device is inserted through a minimally invasive surgical procedure, requiring only two small incisions to place small insulated wires with electrodes in the epidural space, usually between C1 and C3. A small rechargeable battery-powered unit is then implanted, which is controlled wirelessly to modulate pain signals from the trigeminal nerve to the brain. “Once we place and adjust the device, it can stay there for a very long time and doesn’t require much maintenance,” says Lad.

Lad is also expanding the use of SCS to treat DPN. Similar to TN, many patients have refractory DPN that doesn’t respond to medications alone. SCS is now an option for these patients and has been shown to enhance sensation, reduce pain, and improve quality of life. 

“The device is very similar for diabetic neuropathy, except it is implanted in the thoracic spine instead of the cervical spine,” says Lad. 

Duke was part of the pivotal clinical trial that led to FDA approval. Lad is partnering with Duke primary care physicians, podiatrists, and endocrinologists to identify patients with discomfort related to DPN who could benefit from SCS. Many patients refer to it as burning, tingling, or numbness and have tried and failed conservative options, including medications like gabapentin and pregabalin. He adds, “We want to help patients get to us efficiently, so our navigator is ready to help with direct referrals from other specialists to evaluate patients for SCS or other surgical procedures.” 

After referral, the navigator helps patients schedule appointments, imaging, and procedures in a condensed period of time. “We want patients to feel like we’ve got all aspects of their care covered,” says Lad. “The patient’s entire experience is important, and we take ownership in helping them by optimizing convenience and efficiency with the process.”