Post-market Study of the TOPS™ System

Study Overview
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Brief Summary
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The study is being conducted to evaluate look the TOPS System when used in patients with degenerative spondylolisthesis and lumbar spinal stenosis who would normally be candidates for spinal fusion.

Detailed Description
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This study is being conducted to evaluate the TOPS™ SP System from (TOPS™ System or TOPS). TOPS is an alternative to spinal fusion and is designed to stabilize but not fuse the affected vertebral level to alleviate pain stemming from degenerative spondylolisthesis (abnormal/excessive movement of the vertebrae causing pain in the lower back and legs) and spinal stenosis (narrowing of the spinal canal resulting in compression of nerves producing symptoms of pain, numbness and tingling in the legs).

Official Title
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A Study to Evaluate the Safety and Effectiveness of the TOPS System

Conditions
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Lumbar Spinal Stenosis, Spondylolisthesis

Intervention / Treatment
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* Device: TOPS System


Participation Criteria
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Eligibility Criteria
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IInclusion Criteria - Prospective subjects must meet all of the following criteria to be considered eligible for inclusion in this clinic study: Age 40-85 years old; One or both of the following at a single level from L3 to L5; (1) symptomatic monosegmental lumbar spinal stenosis or facet arthrosis, (2) degenerative spondylolisthesis up to and including grade 1. At least three (3) months of failed, conservative treatment prior to surgery (unless deemed inadvisable due to progressive motor weakness or other evidence of rapidly deteriorating condition) including the use of anti-inflammatory medications at maximum specified dosage, administration of epidural/facet injections, rest, heat, electrotherapy and/or physical therapy; Narrowing of the lumbar spinal canal (central and/or foramenal) classified as moderate to severe using CT scans/MRI; VAS leg pain of at least 40/100; Oswestry Disability Index score of at least 40/100; Lower back pain or sciatica with or without spinal claudication and Psychosocially, mentally and physically able to fully comply with the clinical protocol and willing to adhere to follow-up schedule and requirements. Exclusion Criteria - Prospective subjects must not meet any of the exclusion criteria to participate in this clinical study: Primary diagnosis of discogenic back pain at the TOPS System level; Back or non-radicular leg pain of unknown etiology at the index level; Lytic spondylolisthesis at the index level; More than one (1) motion segment involved in the degenerative pathology to the extent that justifies its inclusion in the surgical procedure, unless a decompression alone can be done at that level without compromising stability; Known allergy to titanium and/or polyurethane; Supplemental interbody support required (e.g., bone graft, spacers, VBRs, or fusion cages) at the index level; Clinically compromised vertebral bodies at the affected level(s) due to any traumatic, neoplastic, metabolic or infectious pathology; Deformity of the spine that would compromise the implant, e.g. scoliosis of greater than ten (10) degrees; Morbid obesity defined as a body mass index > 40 or a weight more than 100 lbs. over ideal body weight; DEXA bone density measured T score equal to or lower than - 2.0; Paget's disease, osteomalacia, osteogenesis imperfecta, thyroid and/or parathyroid gland disorder and/or any other metabolic bone disease; Active infection; AIDS, HIV, or active hepatitis; Rheumatoid arthritis or other autoimmune disease; Tuberculosis active or in the past 3 years; Active malignancy: unless treated with curative intent and there have been no clinical signs or symptoms of the malignancy for at least 5 years; Medical condntions requiring treatment with any drugs known to potentially interfere with bone/soft tissue healing; Pregnant or interested in becoming pregnant in the next 3 years; Current chemical/alcohol dependency or significant psychosocial disturbance; Cauda equina syndrome or neurogenic bowel/bladder dysfunction; Severe arterial insufficiency of the legs, peripheral vascular disease; Sustained pathologic fractures of the vertebra or multiple fractures of the vertebra or hip; Significant peripheral neuropathy; Immunologically suppressed, received steroids > 1 month out of the past year; Insulin-dependent diabetes mellitus; Life expectancy less than 3 years; Waddell signs > 3; Currently involved in active spinal litigation OR Subject is incarcerated.

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: TOPS System<br>Post Marketing Study | Device: TOPS System<br>* Non-randomized study involving implantation of a TOPS via lumbar surgery to decompress and provide stability to the index level.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Improvement in ODI and improvement in VAS leg score | Composite endpoint - Subjects who exhibit a reduction of 15 percent in their Oswestry Disability Index (ODI) score compared to their preoperative ODI score AND a reduction of at least 20mm (20% improvement) in either of their VAS Leg Score will be considered a success. | 24 months post implantation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Average improvement in back and leg visual analog scales (VAS) | A failure to meet of any of the secondary endpoints will not be considered a therapeutic failure unless such a failure requires subsequent surgical intervention. | 24 months post implantation | 
| ZCQ Scores | A failure to meet of any of the secondary endpoints will not be considered a therapeutic failure unless such a failure requires subsequent surgical intervention. | 24 months post implantation | 
| Quality of life (SF-36) | A failure to meet of any of the secondary endpoints will not be considered a therapeutic failure unless such a failure requires subsequent surgical intervention. | 24 months post implantation | 
| Maintenance or improvement in neurological symptoms | A failure to meet of any of the secondary endpoints will not be considered a therapeutic failure unless such a failure requires subsequent surgical intervention. | 24 months post implantation |