Clinical trial NCT03115983: LimiFlex Clinical Trial for the Treatment of Degenerative Spondylolisthesis with Spinal Stenosis
Official title: A Concurrently Controlled Study of the LimiFlex™ Paraspinous Tension Band in the Treatment of Lumbar Degenerative Spondylolisthesis with Spinal Stenosis
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: NA
Conditions: Degenerative Spondylolisthesis
Lumbar Spinal Stenosis
Lead sponsor: Empirical Spine, Inc.
Sponsor class: INDUSTRY
Collaborators: name: Biomedical Statistical Consulting
name: Medical Metrics Diagnostics, Inc
name: MCRA
First posted: 2017-04-14
Enrollment: 299
Sex: ALL
Minimum age (years): 25
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Intervention model description: This is a multi-center, prospective, concurrently controlled, non-blinded study. Balance between groups will be achieved through sub classification using propensity scores. Prospective patient sample supplemented with retrospective and/or historical control subjects.
Primary purpose: TREATMENT

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.

Eligibility criteria: Inclusion Criteria (patients must meet ALL of the following criteria to be eligible for participation in the study):

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.

Primary outcomes:
measure: Composite Clinical Success
timeFrame: 24 Months
Secondary outcomes:
measure: Oswestry Disability Index (ODI)
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Neurological Status
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Additional surgical interventions
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Absence of device integrity failures defined as device breakage, device separation or disassembly, or device dislocation
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Estimated blood loss
timeFrame: Procedure
measure: Length of procedure
timeFrame: Procedure
measure: Hospital stay
timeFrame: Immediately upon discharge
measure: Return to normal activities of daily living
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Work status
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Pain medication including narcotics usage
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Visual analog scale (VAS) leg pain
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Visual analog scale (VAS) back pain
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Zurich claudication questionnaire (ZCQ)
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: SF-12 Quality of Life survey
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Patient satisfaction
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
measure: Radiographic fusion status
timeFrame: Both groups: 6 wks, 3 mo, 6 mo, 12 mo, 24 mo, 36 mo, 48 mo, 60 mo
Other outcomes:
Locations:
city: Tempe
country: United States
facility: Sonoran Spine Research and Education Foundation
state: Arizona
city: Oakland
country: United States
facility: Kaiser Permanente Division of Research
state: California
city: Redwood City
country: United States
facility: Stanford University Medical Center
state: California
city: Sacramento
country: United States
facility: UC Davis Spine Center
state: California
city: Sacramento
country: United States
facility: Kaiser Permanente Roseville Clinical Trials Program
state: California
city: San Francisco
country: United States
facility: UCSF Dept of Orthopaedic Surgery
state: California
city: San Jose
country: United States
facility: Kaiser Permanente (San Jose Medical Center)
state: California
city: Santa Monica
country: United States
facility: The Spine Institute, Center for Spinal Restoration and Foundation for Spinal Restoration
state: California
city: Boulder
country: United States
facility: Boulder Neurological & Spine Associates
state: Colorado
city: Miami
country: United States
facility: University of Miami, Dept of Neurological Surgery
state: Florida
city: Tampa
country: United States
facility: BioSpine
state: Florida
city: Atlanta
country: United States
facility: Emory University
state: Georgia
city: Chicago
country: United States
facility: Rush University
state: Illinois
city: Carmel
country: United States
facility: Indiana Spine Group
state: Indiana
city: Louisville
country: United States
facility: Norton Leatherman Spine Center
state: Kentucky
city: Boston
country: United States
facility: Beth Israel Deaconess Medical Center
state: Massachusetts
city: Worcester
country: United States
facility: University of Massachusetts, Dept of Orthopedics and Physical Rehabilitation
state: Massachusetts
city: Royal Oak
country: United States
facility: Beaumont Hospital
state: Michigan
city: Waterford
country: United States
facility: Michigan Minimally Invasive Neurosurgical Institute
state: Michigan
city: St. Louis
country: United States
facility: Washington University School of Medicine
state: Missouri
city: Binghamton
country: United States
facility: UHS Neurosurgery (Binghamton)
state: New York
city: New York
country: United States
facility: Hospital for Special Surgery
state: New York
city: Syracuse
country: United States
facility: SUNY Upstate Medical University
state: New York
city: Columbus
country: United States
facility: The Ohio State University
state: Ohio
city: Philadelphia
country: United States
facility: University of Pennsylvania Hospital
state: Pennsylvania
city: Plano
country: United States
facility: Texas Back Institue, Clincal Research, LLC-Plano
state: Texas
city: Charlottesville
country: United States
facility: University of Virginia Orthopaedic Surgery
state: Virginia
city: Seattle
country: United States
facility: Swedish Medical Center
state: Washington
Study officials:
affiliation: Indiana Spine Group
name: Rick Sasso, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: Pennsylvania Hospital Neurosurgery
name: William C Welch, MD
role: PRINCIPAL_INVESTIGATOR
References: