Spinal Cord Stimulators Adversely Affect Outcomes in Spinal Deformity Surgery. A Retrospective Case-Control Study.

Abstract

Study DesignRetrospective comparative analysis of prospective cohort.ObjectiveTo examine clinical outcomes of patients with preexisting SCS after adult spinal deformity surgery.MethodsA total of 94 patients with and without a previous history of spinal cord stimulator placement undergoing surgery for ASD with minimum 2-year follow-up. Thirty-three patients with SCS undergoing ASD surgery with minimum 2-year follow-up were compared with a matched cohort of 61 ASD patients without SCS.ResultsDespite similar baseline ODI (56 vs 50, <i>P</i> = .11) and back VAS (6.8 vs 6.6, <i>P</i> = .52), SCS patients did worse at all post-op time intervals. At 6 months, the SCS cohort had higher ODI (48 vs 31, <i>P</i> < .001) and VAS (4.8 vs 3.5, <i>P</i> = .01). This difference persisted at 1 year for ODI (46 vs 30, <i>P</i> < .001) but not for VAS (4.7 vs 4.0, <i>P</i> = .19). At 2 years, ODI remained significantly worse in the SCS cohort (49 vs 38, <i>P</i> = .004). Both cohorts had significant improvement at 2 years compared to baseline (SCS: -1.6 VAS, <i>P</i> < .001, -7 ODI, <i>P</i> = .03; Control: -2.5 VAS, <i>P</i> < .001, -13 ODI, <i>P</i> < .001). Radiographic parameters such as curve magnitude, curve correction, and balance were similar between the 2 groups.ConclusionDespite having substantial improvement after ASD surgery, patients with previous SCS placement did significantly worse in both back VAS and ODI postop compared with controls. They also did not experience a decrease in narcotic use at 2 years despite having similar overall radiographic results and complication rates.