MIS MiLIF Versus Open

This is a prospective, multi-center, non-randomized cohort design clinical study to evaluate the clinical outcomes of patients that have a minimally invasive lumbar interbody fusion (MiLIF) through the Atavi system compared to traditional unilateral open lumbar interbody fusion through a midline incision. the study will involve up to approximately 12 investigational sites and enroll up to 126 patients.

Inclusion criteria

• Patient is between 18 and 75 years of age
• Patient is scheduled for an elective spinal lumbar interbody single level fusion
• Patient is a candidate for posterior unilateral lumbar fusion through a midline incision
• Indication for surgery and dominant symptom of chronic low back and/or leg pain
• Diagnosis of one or more of the following:

• Primary symptomatic degenerative disc disease confirmed with appropriate imaging studies and/or positive lumbar discography
• Spondylolisthesis Grade I/II
• The affected motion segment reside in L2-S1 and are adjacent segments
• Patient, or authorized representative, signs a written Informed Consent form to participate in the study, prior to any study mandated determinations or procedure.

Exclusion criteria

• Patient has a known fracture in the lumbar spine
• Patient has systemic infection or evidence of any surgical site infection (superficial or organ space)
• Patient has compromised immune system or autoimmune disease (WBC<4000 or >20,000)
• Patient has uncontrolled diabetes
• Patient has a known malignancy
• Prior lumbar fusion attempt; prior laminectomy and/or discectomy are allowed
• Known medical or anatomical condition that would preclude a posterior lumbar fusion using metallic instrumentation (e.g., severe osteopenia)
• Patient with a planned placement of an electric bone stimulator
• Patient with a planned placement of indwelling epidural catheter for a long term pain management
• Patient is pregnant or wishes to become pregnant during the length of the study participation
• Patient is currently in litigation
• Patient is not likely to comply with the follow-up evaluation schedule
• Patient is participating in a clinical trial of another investigational drug or device.