The objective of this study is to prospectively evaluate the performance of Integra Accell Evo3 Demineralized Bone Matrix as an adjunct for instrumented lumbar spine fusion with a retrospective comparison to a historical patient cohort.

The objective of this study is to prospectively evaluate the performance of Integra Accell Evo3 Demineralized Bone Matrix as an adjunct for instrumented lumbar spine fusion in comparison to a retrospective cohort of Infuse subjects. Infuse subjects were not enrolled in the current study.

Inclusion Criteria:

• Are 18 (eighteen) years of age or older at the time of surgery.
• Require spinal fusion using TLIF, PLF or PLIF, with the use of an interbody spacer, at 1 to 3 levels between L3-S1.
• Willing and able to return for the scheduled follow-up visits, follow post-operative instructions and undergo the required radiographic exams (A/P, Lateral Neutral and Lateral Flexion/Extension X-rays) for up to 3 time points between 6 months and 24 months post-surgery (6±2 months, 12±3 months and 24±4 months post-surgery), including one CT-scan at 12±3 months.
• Unresponsive to conservative care over a period of at least 6 months or has signs and/or symptoms that mandate urgent surgical intervention.

Exclusion Criteria:

• Are long term users of medications (i.e. steroids greater than 2-weeks) that are known to inhibit fusion or bone metabolism at any time within 6 months prior to surgery. Exceptions are inhaled steroids for asthma treatment (i.e. patients on inhaled steroids are allowed), or epidural steroid injections.
• Are taking immunosuppressive agents (Cancer chemotherapy, treatment with Disease Modifying Anti-rheumatic drugs (DMARDs) or any similar immunomodulating drugs) or are treated with Growth Factors or Insulin at any time within 6 months prior to surgery.
• Are being treated with radiotherapy.
• Are having medical conditions, known to impact bone metabolism, such as Paget's disease, osteoporosis.
• Are smokers and/or nicotine/tobacco users.
• Are pregnant, lactating or women wishing to become pregnant.
• Are a prisoner.
• Are currently participating in an investigational drug or another device study that has not completed the primary endpoint or that clinically interferes with the study endpoints.
• Prior spine surgery at the index level except posterior decompressive surgery where the posterior elements are preserved e.g. facet saving techniques such as discectomy, laminotomy, and intradiscal procedures.
• Use of any other bone graft or bone graft substitute in addition to or in place of Accell Evo3® with the exception of local autograft and/or cancellous bone chips.
• Use of routine prophylactic NSAIDS for 3 months post-operatively, but low dose concomitant pain medications e.g. aspirin should be continued and recorded on the Concomitant Pain Medications case report form (CRF).

Up to 24 months post surgery

Adverse events: Any untoward or unfavorable medical occurrence in a participant, including any abnormal sign (for example, abnormal physical exam or laboratory finding), symptom, or disease, temporally associated with the participant's participation in the research, whether or not considered related to the participant's participation in the research