New modalities of neurostimulation: high frequency and dorsal root ganglion.

PURPOSE OF REVIEW: Neurostimulation is a well tolerated, cost-efficient, and effective method to treat chronic pain. Although spinal cord stimulation (SCS) has been shown to help patients, newer modalities such as burst, kilohertz-frequency, and dorsal root ganglion stimulation may provide greater pain relief, fewer paresthesias, and better outcomes. RECENT FINDINGS: Burst stimulation, programed as five-impulse burst at a frequency of 500 Hz, delivers more charge per second than conventional stimulation. Trials of burst stimulation have shown superior pain relief, decreased paresthesias, and patient preference compared with conventional SCS. Kilohertz-frequency SCS uses low-amplitude, high-frequency (10 kHz), and short-duration pulses. The SENZA trial showed superiority in both back and leg pain with greater pain relief as well as decreased opioid use. Dorsal root ganglion stimulation stimulates the ganglion cells allowing for precise targeting of pain regions. Multiple studies, including the ACCURATE trial, have shown superior pain relief in multiple conditions. SUMMARY: Improvements in pain control and patient satisfaction suggest that these new stimulation patterns will greatly increase the utility of neurostimulation; however, clinical trials with broader patient populations have to be done to support more extensive use of these therapies.

Insurance disparities in the outcomes of spinal cord stimulation surgery.

OBJECTIVES: The Affordable Care Act aims to expand health insurance and to help narrow existing health care disparities. Medicaid patients have previously been noted to be at an increased risk for impaired access to health care, delayed medical treatment, and the receipt of substandard care. Conversely, those with commercial insurance may be subject to overtreatment. The goal of this study was to evaluate how Medicaid versus commercial insurance status affects outcomes following spinal cord stimulation (SCS) surgery. MATERIALS AND METHODS: A retrospective cohort study of 13,774 patients underwent either percutaneous or paddle permanent SCS implantation, selected from the Thomson Reuter's MarketScan database between 2000 and 2009. Patients were characterized by age at initial procedure, gender, baseline comorbidity burden, procedure-associated diagnosis code, follow-up, and type of insurance (Medicaid vs. commercial insurance). Outcome measures included probability of reoperation, timing and type of reoperation, presence of postoperative complications (immediate, 30 days, and 90 days), and overall utilization of health resources postoperatively. Multivariate analysis was performed comparing the relative effect of insurance status on outcomes following initial surgery. RESULTS: Medicaid patients had greater healthcare resource utilization as measured by medications prescribed, emergency department visits, and length of stay; however, commercially insured patients had significantly higher overall costs ($110,908 vs. $64,644, p < 0.0001). Commercial and Medicaid patients did not significantly differ in their complication rates during the index hospitalization or at 30 days or 90 days postoperatively. The group were also not significantly different in their two-year reoperation rates (7.32% vs. 5.06%, p = 0.0513). CONCLUSIONS: There are substantial insurance disparities that affect healthcare utilization and overall cost following SCS. Efforts for national healthcare reform should examine system factors that will reduce socioeconomic disparities in outcomes following SCS.