Assessment of nanOss Bioactive 3D in the Posterolateral Spine

• At least 21 years of age and skeletally mature.
• Symptomatic spinal stenosis secondary to DDD with up to Grade 1 spondylolisthesis at one or two adjacent levels from L2-S1 requiring instrumented PLF surgery.
• Completed a minimum of 6 months of non-operative treatment.
• Pre-operative objective evidence of primary diagnosis confirmed by appropriate imaging studies (AP, Lateral, Flexion and Extension images and an MRI or CT scan).
• Is willing and able to return for post-treatment exams according to the follow-up called for in the protocol.
• Is able to review, understand and sign the informed consent document.

Exclusion Criteria:

• Symptomatic at more than two levels.
• Has had previous fusion surgery at the level(s) to be treated (previous discectomy, laminotomy, laminectomy or nucleolysis at the level(s) to be treated \< 6 months ago is ok).
• Has > 11 degrees lumbar scoliosis.
• Has > 40 BMI.
• Has > Grade 1 spondylolisthesis.
• Has osteoporosis (T-score of -2.5 or below), osteomalacia, Paget's disease or metabolic bone disease.
• Has a disease that significantly inhibits bone healing (e.g., diabetes type 1, renal failure, impaired calcium metabolism).
• Has a medical condition that requires or has a history of chronic steroid use (i.e., oral steroids), with the exception of inhaled/nasal corticosteroids steroids or has any medical condition that requires treatment with drugs known to interfere with bone healing.
• Has a neurological disease (e.g., Parkinson's disease), a psychosocial disorder (e.g., suicidal, diminished capacity) or has a history of substance abuse which would preclude accurate evaluation or limit the ability to comply with study requirements.
• Has either an active infection or infection at the site of surgery
• Has a systemic disease (e.g., AIDS, HIV, active hepatitis, tuberculosis)
• Has rheumatoid arthritis or other autoimmune disease.
• Has spinal tumors.
• Has an active malignancy (except non-melanoma skin cancer) or history of any invasive malignancy unless treated and in remission for at least five years.
• Has a known sensitivity or allergies to porcine collagen, PEEK, tantalum or titanium.
• Has active arachnoiditis.
• Has fractures of the epiphyseal plate or fractures for which stabilization of the fracture is not possible.
• Is a prisoner.
• Is involved in spinal litigation at the treated level(s).
• Is participating in another clinical study that would confound Study data.
• Is pregnant or is interested in becoming pregnant while participating in the Study.