Spinal cord stimulator utilization trends and predictors of unsuccessful trial-to-implant conversion

Background context Spinal cord stimulators (SCS) are neuromodulatory devices that may be considered for the management of refractory back or neurologic pain. Purpose To assess the rate and predictors of SCS implantation and failure of trial-to-implant conversion, trends over time, and breakdown of physician specialties implanting SCS. Study design/setting Retrospective case-control study using the 2010 through October 2022 PearlDiver 165 Mariner Patient Claims Database. Patient sample Adult patients who underwent SCS trial. Outcome measures Percentage of SCS trials that converted to permanent implants, clinical and non-clinical variables associated with unsuccessful conversion to permanent implant from trial, and trends over the years of utilization, successful trial-to-implant conversion rate, and physician specialty SCS procedural volume. Methods Adults who underwent SCS trial were identified and categorized into those who did or did not undergo conversion to permanent pulse generator implantation. Multivariable logistic regression was used to identify clinical characteristics (age, sex, Elixhauser Comorbidity Index, and tobacco use) and non-clinical characteristics (insurance plan and US geographic region) independently associated with having lower odds of achieving trial-to-implant conversion. The annual incidence of SCS utilization, trial-to-implant conversion, and physicians performing the procedures (pain specialists, neurosurgeons, orthopedic surgeons). Results Of 265,756 patients undergoing SCS trial, 178,144 (67%) went on to receive permanent implant while 87,612 (33%) did not. Factors independently associated with reduced odds of successful trial-to-implant conversion included: older age (OR: 0.97 per decade increase), male sex (OR: 0.93, relative to female), lower comorbidity burden (OR: 0.96 per 1-point ECI decrease), no documented tobacco use (OR: 0.94), insurance (relative to Commercial, Medicaid [OR: 0.78] and Medicare [OR: 0.85]) and geographic region (relative to Midwest, Northeast [OR: 0.63], West [OR: 0.82], and South [OR: 0.85]) ( P < 0.05 for all). The overall incidence of patients trialing SCS (with or without conversion to implant) increased over the years from 17.9 to 22.9 patients per 100,000 covered lives in the database ( P < 0.05). The rate of successful trial-to-implant conversion increased over the years, from 63.4% in 2010 to 73.3% in 2021 ( P < 0.05). The physician specialties implanting SCS remained similar over the years. Conclusions The overall utilization of SCS and trial-to-implant conversion rates have increased over the years. By defining clinical and nonclinical factors associated with failure for conversion from trial to implant, selection processes can be further optimized by specialists performing these procedures.