The objective of this study is to evaluate the clinical success of AttraX Putty as a bone graft substitute for autograft in XLIF procedures.

This is a single-center, prospective, randomized study. Subjects will be recruited from patients already under the Investigator's care who are indicated for XLIF with iliac crest bone graft (ICBG) autograft or AttraX Putty. To minimize bias, all consecutive patients at a given investigational site who meet eligibility requirements will be asked to consent to participate in the study whereby the biologic (ICBG autograft or AttraX Putty) will be randomly assigned. All subjects will be followed for 24 months following surgery to quantify the clinical and radiographic improvements of each biologic compared to baseline and in comparison with each other.

Inclusion Criteria:

1. Persistent back and/or leg pain unresponsive to conservative treatment for at least 6 months, unless surgical treatment is clinically indicated sooner
2. Indicated for a single-level XLIF between L1 and L5 with bilateral percutaneous pedicle screws
3. Objective evidence of primary diagnosis must be confirmed by appropriate imaging studies
4. 18-80 years of age at the date of written informed consent
5. Able to undergo surgery based on physical exam, medical history, and surgeon judgment
6. Expected to survive at least 2 years beyond surgery
7. Willing and able to return for post-treatment exams according to the follow-up called for in the protocol
8. Signed and dated informed consent form

Exclusion Criteria:

1. Mental or physical condition that would limit the ability to comply with study requirements
2. Spine abnormality requiring treatment at more than one level
3. Previous failed fusion at any spinal level
4. Prior fusion procedure at operative level (i.e., no revision of operative level)
5. Prior adjacent level fusion (note: prior decompression is not an exclusion)
6. Systemic or local infection; active or latent
7. Diseases that significantly inhibit bone healing (e.g., prior diagnosis of osteoporosis, metabolic bone disease)
8. Treatment with pharmaceuticals interfering with calcium metabolism
9. Undergoing chemotherapy or radiation treatment
10. Chronic use of steroids (defined as more than 6 weeks of steroid use within 12 months of surgery, other than episodic use or inhaled corticosteroids)
11. Involvement in active litigation relating to the spine (worker's compensation claim is allowed if it is not contested)
12. Significant general illness (e.g., HIV, active metastatic cancer of any type, uncontrolled diabetes, dialysis dependent renal failure, symptomatic liver disease)
13. Immunocompromised or is being treated with immunosuppressive agents
14. Pregnant, or plans to become pregnant during the study
15. Subject is a prisoner
16. Participating in another clinical study that would confound study data
17. At risk to be non-compliant (e.g. (recently treated for) substance abuse, detainee, likely to immigrate)