Comparison of nanOss Bioactive With Autograft and Bone Marrow Aspirate to Autograft in the Posterolateral Spine

The post market clinical investigation is designed to assess instrumented posterolateral
fusion (PLF) using nanOss Bioactive bone void filler with autograft bone and bone marrow
aspirate in patients with symptomatic spinal stenosis secondary to degenerative disc disease
with up to Grade 1 spondylolisthesis at one or two adjacent levels from L2-S1.

Preoperatively, the participant will provide his/her medical history and complete self
assessment forms. The investigator will perform a clinical evaluation and x-rays will be
performed if recent x-rays are not available. Participants will undergo instrumented PLF with
an interbody fusion device (with autograft or allograft) using nanOss Bioactive in
combination with autograft bone and bone marrow aspirate in one posterolateral gutter and
autograft alone in the opposite posterolateral gutter.

Following surgery, operative and discharge information will be collected and a clinical
evaluation will be performed prior to discharge. Participants will be evaluated 6 and 12
months postoperatively. One investigational site will participate in long-term followup of 24
months. Each participant will complete x-rays and self assessment documents. A CT scan
performed at the 12 month postoperative visit will be evaluated by an independent radiologist
to assess fusion results. Complication data will be recorded throughout the study.

Inclusion Criteria:

- is at least 18 years of age and skeletally mature.

- must have symptomatic spinal stenosis and/or spondylolisthesis or degenerative disc
disease (DDD) at one or two adjacent levels from L2-S1 requiring a fusion.

- must have completed a minimum of three months of unsuccessful conservative,
non-operative care.

- must have discogenic back pain with or without leg pain.

- DDD must be confirmed by MRI or CT scans followed by discography (if necessary).

- must score at least 40% on the Oswestry Disability Index.

- must score at least a 4 on a 10 cm Visual Analog Scale for back pain.

- must be able to comply with the protocol's follow-up schedule.

- must understand and sign the informed consent document.

Exclusion Criteria:

- symptomatic at more than 2 levels.

- previous fusion surgery at any lumbar level with or without instrumentation (prior
discectomy, laminotomy, laminectomy or nucleolysis at the operative (involved) level >
6 months is permitted).

- more than 50% spondylolisthesis.

- lumbar scoliosis greater than 11 degrees.

- osteoporosis, osteopenia, osteomalacia, Paget's disease or metabolic bone disease.

- spinal tumors.

- active arachnoiditis.

- fractures of the epiphyseal plate or fractures for which stabilization of the fracture
is not possible.

- impaired calcium metabolism.

- active infection or surgical site infection.

- rheumatoid arthritis or other autoimmune disease

- chronic steroid use (used steroids for one month within the last 6 months) or any
medical condition that requires treatment with drugs known to interfere with bone
healing.

- systemic disease such as AIDS, HIV, hepatitis (active), tuberculosis.

- morbid obesity defined as body mass index (BMI)>40 or a weight more than 100lbs over
ideal body weight.

- smokers unless the patient agrees to quit at least 2 weeks prior to and for the
duration of the study, confirmed by a carboxyhemoglobin test prior to surgery.

- psychosocial disorders that would preclude accurate evaluation or has a history of
substance abuse.

- active malignancy except non-melanoma skin cancer; history of any invasive malignancy
unless treated and in remission for at least five years.

- documented allergies to porcine collagen or titanium

- pregnancy, or interested in becoming pregnant in the next four years.

- participation in another investigational study within 30 days.