LimiFlex Clinical Trial for the Treatment of Degenerative Spondylolisthesis With Spinal Stenosis

NCT ID: NCT03115983

Last Updated: 2025-08-07

Basic Information

• Recruitment Status: ACTIVE_NOT_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 299 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2017-07-17
• Study Completion Date: 2026-01-16

Brief Summary

The LimiFlex™ Clinical Trial is a prospective, concurrently controlled, multi-center study to evaluate the safety and effectiveness of decompression and stabilization with the Empirical Spine LimiFlex™ Paraspinous Tension Band compared to decompression and transforaminal lumbar interbody fusion (TLIF) with concomitant posterolateral fusion (PLF) for the treatment of lumbar degenerative spondylolisthesis (Grade I per Meyerding classification) with spinal stenosis. Clinical trial sites will enroll solely LimiFlex subjects or solely TLIF/PLF subjects.

Detailed Description

The LimiFlex™ Paraspinous Tension Band is a new stabilization option for patients being treated with surgical decompression for degenerative spondylolisthesis. The LimiFlex does not require pedicle screws to anchor to the spine; instead, two dynamic rods are attached to pedicle-sparing straps which encircle adjacent spinous processes.

Conditions

Degenerative Spondylolisthesis; Lumbar Spinal Stenosis

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

LimiFlex

Posterior dynamic stabilization with the LimiFlex Paraspinous Tension Band

Group Type: EXPERIMENTAL

LimiFlex

Intervention Type: DEVICE

LimiFlex implantation at a single level after surgical decompression.

Decompression

Intervention Type: PROCEDURE

Surgical decompression at one or two contiguous levels from L1 to S1.

Fusion

Transforaminal lumbar interbody fusion with concomitant posterolateral fusion with pedicle screw instrumentation

Group Type: ACTIVE_COMPARATOR

Fusion Instrumentation

Intervention Type: DEVICE

Titanium alloy top-loading, polyaxial pedicle screws and cylindrical, titanium alloy rod instrumentation using autograft and/or allograft bone (i.e., cancellous and/or corticocancellous bone only), and/or a synthetic bone graft extender that is on-label for these indications (i.e., decorticated posterolateral gutter only). The TLIF requires a single PEEK or Titanium TLIF cage cleared by FDA for this indication filled with autograft and/or allograft bone (i.e., cancellous and/or corticocancellous bone only).

Decompression

Intervention Type: PROCEDURE

Surgical decompression at one or two contiguous levels from L1 to S1.

Fusion

Intervention Type: PROCEDURE

Transforaminal lumbar interbody fusion (TLIF) with concomitant posterolateral fusion (PLF) at a single level after surgical decompression.

Interventions

LimiFlex

LimiFlex implantation at a single level after surgical decompression.

Intervention Type: DEVICE

Fusion Instrumentation

Titanium alloy top-loading, polyaxial pedicle screws and cylindrical, titanium alloy rod instrumentation using autograft and/or allograft bone (i.e., cancellous and/or corticocancellous bone only), and/or a synthetic bone graft extender that is on-label for these indications (i.e., decorticated posterolateral gutter only). The TLIF requires a single PEEK or Titanium TLIF cage cleared by FDA for this indication filled with autograft and/or allograft bone (i.e., cancellous and/or corticocancellous bone only).

Intervention Type: DEVICE

Decompression

Surgical decompression at one or two contiguous levels from L1 to S1.

Intervention Type: PROCEDURE

Fusion

Transforaminal lumbar interbody fusion (TLIF) with concomitant posterolateral fusion (PLF) at a single level after surgical decompression.

Intervention Type: PROCEDURE

Other Intervention Names

LimiFlex Paraspinous Tension Band

Eligibility Criteria

Inclusion Criteria

1. Lumbar degenerative spondylolisthesis (Grade I per Meyerding classification), at one level from L1 to S1, with radiographic confirmation using X-ray;

a. Grade I spondylolisthesis per Meyerding classification includes up to 25% anterior translation of a vertebra relative to the superior endplate of the subjacent vertebra at the index level. A patient is considered to have spondylolisthesis with a minimum 10% anterolisthesis at the affected level in a lateral x-ray image.

2. Lumbar spinal stenosis requiring decompression at up to two contiguous levels from L1 to S1, inclusive of the level diagnosed with degenerative spondylolisthesis, and confirmed radiographically using CT or MRI;

a. At the index level, lumbar spinal stenosis is at least moderate lumbar canal stenosis, defined as more than 25% reduction of the cross-sectional area compared with the next adjacent normal level, with nerve root crowding compared with the normal level, as determined by the investigator on CT Scan or MRI.

3. Neurogenic claudication or radiculopathy symptoms including leg pain, muscle weakness, and/or sensation abnormality, with or without back pain as evidenced by patient history;

4. Persistent symptoms despite at least 3 months of conservative treatment that may include but is not limited to physical therapy, medications, and/or epidural injections;

5. A pre-operative Visual Analog Scale (VAS) leg pain score of ≥50 on a 100 mm scale;

• Leg pain includes hip and/or buttock pain on the same side

6. A pre-operative Oswestry Disability Index (ODI) score ≥35 points on a 100-point scale;

7. Candidate for surgical decompression at a single level or two contiguous levels, with stabilization at only one level between L1-S1;

8. Posterior element anatomy is appropriate for interspinous fixation including prediction of presence of spinous processes of segment to be instrumented following decompression (investigational AND control groups) and a prediction of >50% of facet joints present following decompression (investigational group only);

9. ≥25-80 years of age and skeletally mature;

10. Patient has the necessary mental capacity to participate and is willing and able to participate in the study for the duration of the study follow-up and is able to comply with study requirements; and

11. Patient is willing to provide Informed Consent for study participation.

Exclusion Criteria

1. A primary and predominate diagnosis of discogenic back pain;

2. A primary and predominate diagnosis of facet-mediated back pain;

3. Back or non-radicular leg pain of unknown etiology;

4. Significant peripheral vascular disease causing vascular claudication;

5. Significant peripheral neuropathy caused by conditions other than spinal stenosis;

6. History of fixed or permanent neurological deficit related to spinal cord injury;

7. History of any previous surgery* at any level in the lumbosacral spine except for a discectomy or decompression;

8. History of any previous surgery* at the level planned for treatment;

• previous surgery includes spinal stimulator placement but does NOT include epidural injections, rhizotomy or nerve ablation.

9. Isthmic spondylolisthesis or spondylolysis (pars fracture) at any level in the lumbar spine;

10. Clinically significant compromise of vertebrae at L1 to S1 levels due to osteoporotic vertebral compression fracture or any traumatic, neoplastic, metabolic or infectious pathology or congenital abnormality;

11. Spinous process fracture(s) or other posterior element fracture(s) of the segment to be instrumented that would preclude secure fixation of the LimiFlex Device to the spinous process;

12. Spinous process insufficiency or deformity that would preclude secure fixation of the LimiFlex Device to the spinous process including spinous process length <10 mm from lamina to dorsal tip or other significant deformity due to trauma, or congenital abnormality such as spina bifida occulta at the planned instrumented level that would preclude secure fixation of the LimiFlex Device to the spinous process;

13. The estimated distance between the LimiFlex Device strap attachment points (midpoint of the cranial edge of the cranial spinous process and the midpoint of the caudal edge of the caudal spinous process) is <30mm on pre-operative lateral standing radiographs at the segment to be instrumented;

14. Degenerative lumbar scoliosis with a Cobb angle >10° at the affected motion segment;

15. Symptomatic lumbar stenosis that is not amenable to a direct decompression

16. Anklyosed motion segment at the target operative level

17. Severe osteoporosis, defined as history of fragility fracture and DXA T-score <-2.5 or QCT T-score <80mg/cubic cm. History of a fragility fracture requires that a DXA scan or QCT scan is completed;

18. Planned hip or knee replacement surgery, severe osteoarthritis or other musculoskeletal pathology of the hip or leg that could preclude reliable patient self reporting assessment scales and/or that would likely progress to surgery during study period;

19. Documented allergy to titanium or polyethylene;

20. Active local or systemic infection;

21. Receiving immunosuppressive or long-term steroid therapy;

22. Known history of bone metabolic disorder, including Paget's disease, hyperparathyroidism, renal osteodystrophy, and osteomalacia;

23. Disease or condition that would preclude accurate clinical evaluation of the safety and effectiveness of the study treatment or any significant medical conditions which would place the patient at excessive risk for surgery, such as:

1. severe rheumatoid arthritis or other severe autoimmune disease

2. active hepatitis (viral or serum) or HIV positive

3. unstable cardiac disease

4. uncontrolled diabetes

5. renal failure

6. severe muscular, neural or vascular diseases that endanger the spinal column

7. cauda equina syndrome

8. severe neurologic disorders including paralysis

24. Morbid obesity defined as BMI >40;

25. Active malignancy or history of metastatic malignancy within the last five years;

26. Women who are pregnant or are interested in becoming pregnant within the study period;

27. Currently seeking or receiving worker's compensation for back pain or spinal condition;

28. Currently involved in spinal litigation that potentially is associated with secondary financial gain;

29. Current involvement in a study of another investigational product for similar purpose;

30. Demonstrates three or more Waddell's Signs of Inorganic Behavior;

31. Active treatment of a major psychiatric condition, such as major depression, anxiety disorder, bipolar disorder, schizophrenia, personality disorder, that could prevent accurate completion of self reporting assessment scales;

32. Current history (within 12 months) of substance abuse, including alcohol abuse; or

33. A prisoner.

• Minimum Eligible Age: 25 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Biomedical Statistical Consulting

UNKNOWN

Sponsor Role: collaborator

Medical Metrics Diagnostics, Inc

INDUSTRY

Sponsor Role: collaborator

MCRA

INDUSTRY

Sponsor Role: collaborator

Empirical Spine, Inc.

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Rick Sasso, MD

Role: PRINCIPAL_INVESTIGATOR

Indiana Spine Group

William C Welch, MD

Role: PRINCIPAL_INVESTIGATOR

Pennsylvania Hospital Neurosurgery

Locations

Sonoran Spine Research and Education Foundation

Tempe, Arizona, United States

Kaiser Permanente Division of Research

Oakland, California, United States

Stanford University Medical Center

Redwood City, California, United States

UC Davis Spine Center

Sacramento, California, United States

Kaiser Permanente Roseville Clinical Trials Program

Sacramento, California, United States

UCSF Dept of Orthopaedic Surgery

San Francisco, California, United States

Kaiser Permanente (San Jose Medical Center)

San Jose, California, United States

The Spine Institute, Center for Spinal Restoration and Foundation for Spinal Restoration

Santa Monica, California, United States

Boulder Neurological & Spine Associates

Boulder, Colorado, United States

University of Miami, Dept of Neurological Surgery

Miami, Florida, United States

BioSpine

Tampa, Florida, United States

Emory University

Atlanta, Georgia, United States

Rush University

Chicago, Illinois, United States

Indiana Spine Group

Carmel, Indiana, United States

Norton Leatherman Spine Center

Louisville, Kentucky, United States

Beth Israel Deaconess Medical Center

Boston, Massachusetts, United States

University of Massachusetts, Dept of Orthopedics and Physical Rehabilitation

Worcester, Massachusetts, United States

Beaumont Hospital

Royal Oak, Michigan, United States

Michigan Minimally Invasive Neurosurgical Institute

Waterford, Michigan, United States

Washington University School of Medicine

St Louis, Missouri, United States

UHS Neurosurgery (Binghamton)

Binghamton, New York, United States

Hospital for Special Surgery

New York, New York, United States

SUNY Upstate Medical University

Syracuse, New York, United States

The Ohio State University

Columbus, Ohio, United States

University of Pennsylvania Hospital

Philadelphia, Pennsylvania, United States

Texas Back Institue, Clincal Research, LLC-Plano

Plano, Texas, United States

University of Virginia Orthopaedic Surgery

Charlottesville, Virginia, United States

Swedish Medical Center

Seattle, Washington, United States

Countries

United States

References

Maislin G, Keenan BT, Alamin TF, Fielding LC, Scherman A, Hachadoorian R, Pierre C, Sasso RC, Lavelle WF, Chapman J. Are Randomized Trials Better? Comparison of Baseline Covariate Balance of a Propensity Score-Balanced Lumbar Spine IDE Trial and Comparable RCTs. Global Spine J. 2025 Jul;15(6):2923-2930. doi: 10.1177/21925682251316287. Epub 2025 Jan 27.

Reference Type: DERIVED

PMID: 39868633 (View on PubMed)

Other Identifiers

LSS17001

Identifier Type: -

Identifier Source: org_study_id