Early Functional Outcomes in Low Back Pain Subjects with a Novel Interspinous Fusion Device: REFINE Study 6-Month Results

Abstract

Purpose

Lumbar interlaminar decompression with interspinous fixation is an established safe and effective treatment for spinal stenosis. Early maintenance of improvements in pain intensity and function are critical for durability of symptom relief. The purpose of this study was to investigate the efficacy of minimally invasive treatments for low back pain during the early period after treatment and their utility in setting the course for longer term success.

Patients and Methods

This study utilized patient evaluations at 3- and 6-months following treatment and is part of an actively enrolling, institutional review board (IRB) approved, single-arm, multicenter, prospective, open-label 12-month study. Clinical efficacy was assessed primarily using the change from baseline in Oswestry Disability Index (ODI), Visual Analog Scale (VAS) of the back and leg pain during walking and standing, and Zurich Claudication Questionnaire (ZCQ), and secondarily using the Patient Global Impression of Change (PGIC) and Patient-Reported Outcomes Measurement Information System (PROMIS) 29 v2.1. The safety endpoints were the adverse events and reoperations or revisions at the index level(s).

Results

At 6-month post-op, 76%, 62%–64%, and 64% of patients demonstrated clinical meaningful, and statistically significant improvement in their pain as defined by ZCQ, VAS (back and leg), and ODI, respectively. In addition, 78% of patients noted improvement in PGIC. Two procedure-related adverse events were noted which fully resolved without surgical intervention.

Conclusion

This 6-month interim analysis at 42% enrollment of patients was conducted to determine prolonged safety and efficacy of the interspinous fusion device. Our analysis showed a sustained improvement in clinical efficacy, and safety endpoints, when compared to the 3-months evaluations, across both interventional pain and neurosurgery specialties.

Keywords:

• interspinous fixation
• degenerative disc disease
• neurogenic claudication
• spinal stenosis

Data Sharing Statement

The clinical trial data of this article will not be shared.

Ethics Approval and Informed Consent

IRB approval was provided by Western IRB (IRB #20211168). All patient data collected were de- identified to provide patient data confidentiality and compliance with the Declaration of Helsinki. The protocol and IRB were each approved by the local governing entities of each involved institution. All enrolled subjects provided voluntary written informed consent to participate. Subjects were allowed to ask questions and were given a copy of the informed consent.

Acknowledgments

The authors would like to thank the study participants, as well as Eric Bruntlett, Kamren Murrell for their support in the project management and statistical analysis for this study.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

SMF serves as a consultant for Abbott, Medtronic, Saluda, VertiFlex, Vertos, Surgentec, CornerLoc, Mainstay and Relievant, has received grant for research funding from Mainstay, Relievant, Medtronic, Abbott, VertiFlex, Saluda, Nalu, CornerLoc, Aurora, Biotronik, and Stimgenics, and has an equity position in SynerFuse, Aurora Spine, Thermaquil. SPR Therapeutics, Saluda, CornerLoc, PainTEQ, Stimgenics, Anesthetic Gas Reclamation, Neural Integrative Solutions, SpineThera, and Celeri Health. LJR serves on the speakers Bureau for Boston Scientific, Aurora Spine, SurGen Tec, Vertiflex, and FloSpine. He is a Stockholder for Aurora Spine and receives Royalties from Flospine and SurGen Tec. VM serves as a consultant for Medtronic and Aurora and has received educational support from Medtronic, Abbott, Boston Scientific, Nevro, Vertos, Stimwave, Nalu, Aurora, Spinal Simplicity, SI Fix. AN serves as a consultant for Nevro, Flowonix, Boston Scientific, Surgentec, Aurora Pain and Spine; has received research support from Nevro, Corner Loc, Cardio Surgical Partners, Flowonix and Reno Tahoe Pain Associates. DP serves as a consultant for Abbott, AbbVie, AIS, Allergan, Amgen, Aurora Spine, CornerLoc, Flowonix, Lundbeck, Pajunk Medical, Saluda, Spark Biomedical, Vertos, has received grant and research support from Abbott, Flowonix, Nevro, Saluda and Vertiflex, serve on the Speaker Bureau or Honoraria for Abbott, Allergan, Amgen, CornerLoc, Lundbeck, Saluda, Vertos, and has equity in CornerLoc. MDD is a consultant for Medtronic, Abbott, and Aurora spine and has Stock Options at Aurora Spine. RJ serves as a consultant for Abbott and Medtronic and has research or grant support from Medtronic and Stimgenics. RSV serves as a consultant for Medtronic, Nevro, BSCI and Aurora Spine; teaching agreements with Medtronic, Nevro, BSCI, and Aurora Spine; research associated funding with Medtronic, Nevro, BSCI, PainTEQ, Aurora Spine, Vertos, and Vertiflex; Investments with Medtronic, Nevro and Aurora Spine. SK is a consultant for Aurora Spine Corp., Synaptive Medical Inc., and Osseus Spine; and a shareholder in Aurora Spine Corp. and Synaptive Medical Inc. YJ serves as a consultant for Medtronic, Aurora, Abbott, NALU, Sprint, and PainTEQ; research associated funding with Aurora, Abbott, Sprint, and PainTEQ. JEP serves as a consultant for Abbott, Medtronic, Saluda, Flowonix, SpineThera, Painteq, Vertos, Vertiflex, SPR Therapeutics, Tersera, Aurora, Spark, Ethos, Biotronik, Mainstay, WISE, Boston Scientific, Thermaquil; has received grant and research support from: Abbott, Flowonix, Saluda, Aurora, Painteq, Ethos, Muse, Boston Scientific, SPR Therapeutics, Mainstay, Vertos, AIS, Thermaquil; and is a shareholder of: PainTEQ, Vertos, SPR Therapeutics, Aurora, Spark, Celeri Health, Neural Integrative Solutions, Pacific Research Institute, Thermaquil and Anesthetic Gas Reclamation. He also reports a patent “DRG Neuromonitoring” licensed to NIS. ORR serves as a consultant for Aurora, PainTEQ, Alevio, Captiva, Synergy, Facet Dynamics, Zavation, 3Spine, Vyrsa, Spinal Simplicity, AlloSource, Olympus Terumo Biomaterials, OsteoCentric Technologies. The authors report no other conflicts of interest in this work.