"A prospective, randomised study comparing the use of Actifuse™ ABX synthetic bone substitute with INFUSE® in patients requiring posterolateral instrumented lumbar fusion with interbody fusion" also referred to as: APPRAISE T1 (A Prospective PLF Randomised Actifuse InfuSe Evaluation Trial 1)

INTERVENTION: Trade Name: InductOs Pharmaceutical Form: Kit for implant CONDITION: Prospective trial participants will have been diagnosed with degenerative disc disease with a treatment option of decompression and Interbody Fusion with Posterolateral Intertransverse Process Fusion and Internal Fixation achieved by pedicle screws and rods. ; MedDRA version: 9.1 Level: LLT Classification code 10024992 Term: Lumbar disc disease PRIMARY OUTCOME: Main Objective: The primary objective of this clinical trial is to evaluate the success rates of ACTIFUSE™ ABX and INFUSE® to achieve bone growth and bone fusion. Primary end point(s): Fusion, defined as evidence of bridging trabecular bone present at 1 year as assessed by CT scan (grade 4 or 5) as well as a determination of no motion as assessed by plain radiographs.; ; CT scans will be graded as follows:; ; 1. Demonstrating no fusion on either side (grade 1); 2. Partial or limited unilateral fusion (grade 2); 3. Partial or limited bilateral fusion (grade 3); 4. Solid unilateral fusion (grade 4); 5. Solid bilateral fusion (grade 5); ; No motion defined as: ; a. No more that 3 mm difference in translation on the lateral flexion/extension radiographs as determined by superimposing the two views one upon the other.; b. Less than 5 degrees difference in angular motion between flexion and extension.; Secondary Objective: The secondary objectives of this clinical trial will be to assess clinical outcome measurements. INCLUSION CRITERIA: Each patient participating in the clinical trial must meet the following INCLUSION CRITERIA: 1 Has degenerative disc disease of the lumbar spine as indicated by back pain of discogenic/degenerative origin, with or without leg pain, and has one or more of the following conditions as documented by plain X‐rays, CT scan or MRI scan: • Modic changes. • High intensity changes in the annulus. • Loss of disc height. • Decreased hydration of the disc. • Canal stenosis with or without spondylotic slip. • Gross facet joint changes requiring fusion for treatment. • Have documented annular pathology by other means. (e.g., with discography). 2 Has a preoperative Oswestry Back Disability Score of 30 or more. 3 Aged 18 to 75 years and skeletally mature at time of surgery. 4 Has not responded to non‐operative treatment (e.g., bed rest, physical therapy, medications and/or spinal injections) for a period of six months. 5 If of childbea