Lumbar Spinal Fusion Treatment Study

This study will be a pivotal, multi-center, prospective, randomized, concurrently controlled study of the TOPS System versus a spinal fusion control. Subjects will be randomized in a 2:1 ratio to receive either the treatment device or lumbar spinal fusion. Subjects will be blinded to their treatment assignment until after their surgery.

Prospective subjects must meet all of the inclusion criteria to participate in this clinical study.

In order to participate you must meet the following criteria:

• Are between 35 and 80 years of age.
• Demonstrate at the level to be treated (L2/3, L3/4 or L4/5) all three of the following;

1. Degenerative spondylolisthesis or retrolisthesis up to Grade I, as determined by the investigator based on flexion/extension X-rays.
2. At least moderate lumbar spinal stenosis, defined as greater than a 33% reduction in either the central canal, the lateral recess space, and/or the foramen when compared to an adjacent level, as determined by the investigator based on MRI.
3. Thickening of the ligamentum flavum and/or scarring of the facet joint capsule as identified by the investigator based on MRI.

• Have had at least six (6) months of failed conservative treatment prior to surgery (e.g., physical therapy, use of anti-inflammatory medications at maximum recommended dosage; administration of epidural/facet injections and/or nerve block).
• Have an Oswestry Disability Index (ODI) score of at least 40/100 at baseline.
• Have leg pain with a VAS score of at least 40/100 for at least one leg at baseline1.
• Have neurogenic claudication (as defined by worsening leg/buttock symptoms when walking or standing, which is reduced when sitting or bending forward).
• Demonstrate worse symptoms (e.g., pain, numbness, burning sensation, pin prick sensation, etc.) in the legs/buttock than in the lower back.
• Are psychosocially, mentally and physically able to fully comply with the clinical protocol.
• Are willing to adhere to the follow-up schedule and protocol requirements.
• Are willing and able to understand and sign the study-specific, IRB approved consent form.

This is a partial list of eligibility requirements. To inquire about your eligibility, please call the contact number provided. If you wish to inquire via email, please include the title of the study in your message.