FDA Trial of Paraspinous Tension Band for Degenerative Spondylolisthesis: Preliminary Safety and Outcomes in 100 Subjects With 6-Months Follow-up

Presented at SMISS Annual Forum 2019
By Hyun Bae MD
With Ivan Cheng MD, Rick Sasso MD, Alan Villavicencio , William F. Lavelle MD, Timothy Yoon MD, Ravi Bains MD, Kuo Calvin MD, Kim Kee MD, Harvinder Sandhu MD, Michael Stauff MD, Khalid Sethi MD, Jeff Fischgrund MD, William Welch MD, Reginald J. Davis MD, Elizabeth Yu MD, Harel Deutsch MD, Sigurd Berven MD, Matthew Mermer MD, Umesh Metkar MD, Ammar Hawasli MD, Dennis Crandall MD, Todd Alamin MD, Richard Tallarico MD, Rick Guyer MD,

Disclosures: Hyun Bae MD A; Pfizer, Rebosis, Empirical Spine, Medtronic, Simplify Medical, Mesoblast. B; Stryker K2M, DePuy Synthes, Prosidyan, NuVasive. D; Prosidyan, DiFusion, Stryker, NuVasive, Medtronic. F; Stryker K2M, N Ivan Cheng MD A; Empirical Spine. B; NuVasive, SpineCraft. D; NuVasive, Cytonics, SpinalCyte, Spine Surgical Innovations. F; NuVasive, Globus Medical, Spine Wave., Rick Sasso MD B; NuVasive. F; Medtronic., Alan Villavicencio A; Empirical Spine., William Lavelle MD A; Empirical Spine, DePuy Synthes, Medtronic, Stryker K2M, Spinal Kinectics, Vertebral Technologies. D; 4WEB, Prosidyan, Cardan Robotics., Timothy Yoon MD A; Empirical Spine, NuVasive, Medtronic, Zimmer Biomet, AOSpine. D; Phygen Spine, Alphatec Spine, Meditech Spine. F; Meditech Spine, Stryker., Ravi Bains MD A; Empirical Spine., Kuo Calvin MD A; Empirical Spine., Kim Kee MD A; Empirical Spine, Medtronic, Vertex, Mesoblast, InViVo, Therapeudics, FzioMed, Seikagaku. B; MiRus, Globus Medical, Zimmer Biomet. D; Molecular Matrix. F; Zimmer Biomet, Precision Spine., Harvinder Sandhu MD A; Empirical Spine. B; BioRestorative Therapies, Prosidyan. D; Spine Wave, Paradigm Spine, Providence Medical Technology., Michael Stauff MD A; Empirical Spine. B; Intrinsic Spine., Khalid Sethi MD None., Jeff Fischgrund MD None, William Welch MD A; Empirical Spine., Reginald Davis MD None, Elizabeth Yu MD A; Empirical Spine. C; Johnson & Johnson, AOSpine., Harel Deutsch MD A; Empirical Spine. B; Titan Spine., Sigurd Berven MD A; NIH, NSF, AOSpine, Empirical Spine. B; Medtronic, Stryker, Globus Medical, Innovasis, Medicrea. D; Green Sun Medical, Providence Medical Technology. F; Medtronic, Stryker K2M., Matthew Mermer MD A; Empirical Spine., Umesh Metkar MD A; Empirical Spine., Ammar Hawasli MD A; NREF, CSRS. B; Johnson & Johnson, Cerapedics., Dennis Crandall MD A; Empirical Spine., Todd Alamin MD A; Empirical Spine. B; Empirical Spine., Richard Tallarico MD A; Empirical Spine, Medtronic, Stryker K2M, Spinal Kinectics, Vertebral Technologies. B; Stryker K2M., Rick Guyer MD A; Empirical Spine.,


Degenerative spondylolisthesis (DS) with lumbar spinal stenosis (LSS) is commonly treated with decompression and fusion. The LimiFlex Paraspinous Tension Band (PTB; Empirical Spine, San Carlos, CA) is an alternative stabilization technique for patients with DS and LSS.


The purpose of this study is to assess the operative safety and short-term outcomes of PTB compared to transforaminal lumbar interbody fusion (TLIF) for patients with DS and LSS.


Patients undergoing decompression for single-level Grade 1 DS with LSS were enrolled in the open-label, multicenter, FDA-IDE study with 2 arms: decompression with PTB or TLIF. Perioperative and patient-reported clinical outcomes were recorded at baseline, and postoperatively at 6 weeks, 3 months, and 6 months. All patients who reached a minimum of 6-months follow-up were included in this interim analysis. Summary statistics are reported, as well as paired t-tests to assess within-group changes in pain and disability scores.


One hundred patients (63 PTB, 37 TLIF) reached 6-months follow-up. Characteristics of PTB and TLIF groups, respectively, were: age 64.5±8.2, 63.9±7.4 yrs; BMI 28.4±4.9, 29.3±5.7; current smokers 2%, 3%. Perioperative outcomes were: operative time 113±29 (PTB) and 174±57 (TLIF) minutes; EBL 44±29 (PTB) and 258±167 (TLIF) mL; LOS 0.6±1.5 (PTB) and 3.4±1.7 (TLIF) days. A statistically significant reduction from baseline to 6 months for mean VAS leg (80.5±9.7 to 19.9±23.0), VAS back (65.6±23.5 to 15.8±21.6), and ODI scores (53.1±12.4 to 13.2±14.1) was reported for PTB patients (all p<0.01); with 87% of patients achieving 20 point ODI improvement. Similar improvements were reported for TLIF patients for VAS leg (78.7±15.7 to 27.9±33.4), VAS back (71.7±18.4 to 22.9±26.8), and ODI (51.2±12.8 to 19.7±21.2) (all p<0.01); with 70% achieving 20 point ODI improvement. During the 6-month follow-up period, 1 PTB subject (1.6%) was revised to posterolateral fusion during the initial hospital stay due to intraoperative spinous process fracture resulting in inability to place the PTB, and 2 (5.4%) TLIF subjects were revised to L3-S1 fusions due to symptom progression, including 1 instance of cage/screw migration.


These preliminary results suggest PTB stabilization after decompression for DS with LSS can be accomplished safely without a significant increase in perioperative complications. Short-term improvements in patient-reported outcomes for LimiFlex treated patients are comparable to fusion treated patients. Further investigation will include quantitative comparison between propensity score-matched groups with long-term follow-up.

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