173 Electrical Stimulation Used as an Adjunct to Cervical Spine Fusion in Patients at Risk for Pseudarthrosis

Abstract

INTRODUCTION: Prior studies show that pulsed electromagnetic field (PEMF) stimulation promotes bone healing and can be a valuable tool to help overcome biological deficiencies in patients at risk. The current study further evaluates the adjunct effect of PEMF in subjects undergoing cervical spinal surgery presenting with risk factors for pseudarthrosis. METHODS: A prospective multicenter clinical trial (NCT 03177473) was conducted at eleven clinical sites. Subjects undergoing cervical spinal fusion surgery with one or more risk factors for pseudarthrosis were identified for enrollment. Risk factors for pseudarthrosis included multilevel fusion, prior failed cervical spine fusion, diabetes, osteoporosis, or smoking. Subjects undergoing cervical spinal fusion were required to wear the PEMF device for 4 hours/day for 6 months post-op. Fusion status was determined at the 12-month visit using anterior/posterior, lateral, and flexion/extension radiographs and computed tomography (without contrast). NDI, EQ-5D, SF-36, and VAS for neck and arm pain were collected as secondary outcome measures. RESULTS: Out of 160 subjects, 144 (90.0%) were graded as fused (all levels) at the 12-month visit. Fusion success was 91.7% (n = 55/60), 89.0% (n = 89/100), and 90.9% (n = 20/22) for subjects with 1, 2+, or 3+ risk factors, respectively. Significant improvements in NDI, SF-36, EQ-5D, VAS-arm and VAS-neck were observed compared to baseline (p < 0.001). A device compliance rate of 85.0% was observed at 3-months and 78.3% at 6-months in subjects who had successful cervical fusion. CONCLUSIONS: The PEMF bone growth stimulator device is a valuable tool to aid in fusion healing, especially in challenging populations. Subjects in this study experienced favorable fusion rates of 90% and significant improvement in patient reported outcomes despite having elevated comorbidity and/or complex surgeries.