Prospective, Multi-Center Clinical Outcomes Study Evaluating the chronOS Strip Combined With Bone Marrow Aspirate

The chronOS Strip is a synthetic bone void filler manufactured from chronOS beta-tricalcium phosphate (β-TCP) granules and a resorbable polymer [poly(lactide-co-ε-caprolactone)]. The result is a porous, osteoconductive, three-dimensional composite that is flexible, with excellent memory characteristics. The chronOS Strip conforms to the implant site, allowing site-specific placement.

The use of the chronOS Strip eliminates the need for autologous bone graft harvesting from a secondary surgical site, thus reducing donor site morbidity. The chronOS Strip, combined with autogenous blood and/or bone marrow aspirate, or autograft such as may be obtained from the posterior spinal elements, is intended to be used in the spine for posterolateral fusion. Following placement into the bony void, chronOS Strip resorbs and is replaced with bone during the healing process.

The use of the chronOS Strip eliminates the need for autologous bone graft harvesting from a secondary surgical site, thus reducing donor site morbidity. The chronOS Strip, combined with autogenous blood and/or bone marrow aspirate, or autograft such as may be obtained from the posterior spinal elements, is intended to be used in the spine for posterolateral fusion. Following placement into the bony void, chronOS Strip resorbs and is replaced with bone during the healing process. The chronOS Strip has several handling advantages over existing ceramic bone void fillers traditionally utilized in spine fusion surgery. It is easily shaped to precisely fill the skeletal void and stays localized once placed. Further, the implant can be rolled, folded, cut or sutured intra-operatively, and then conformed to each patient's anatomy.

The chronOS Strip is available in various sizes and thicknesses. It is provided in a sterile perfusion pack which, when connected to a standard syringe, can be used to perfuse the chronOS Strip with the patient's blood and/or bone marrow aspirate.

Inclusion Criteria:

1. Has the following indication for posterolateral fusion (transverse process and facet fusion) with posterior rod and screw fixation:

   • Degenerative Disc Disease, with or without stenosis. Diagnosis of DDD requires back and/or leg (radicular) pain along with:

   1. Instability (≥ 3 mm translation or ≥ 5° angulation); or
   2. MRI confirmation of Modic Type 1 or Type 2 changes; or
   3. High intensity zones in the disc space.
2. Has one or two motion segment(s) to be fused between L2 and S1;
3. Skeletally mature adult, at least 18 years of age at the time of surgery;
4. Oswestry Low Back Pain Disability Questionnaire score ≥ 30 (out of 100);
5. Has completed at least 6 months of conservative therapy, which may include physical therapy, bracing, systemic or injected medications;
6. Psychosocially, mentally and physically able to fully comply with this protocol including adhering to scheduled visits, treatment plan, completing forms, and other study procedures;
7. Personally signed and dated informed consent document prior to any study-related procedures indicating that the patient has been informed of all pertinent aspects of the study.

Exclusion Criteria:

1. Three or more motion segments to be fused;
2. Degenerative scoliosis, defined as Cobb angle > 10° at any level in lumbar spine;
3. Has had a previous interbody fusion or posterolateral fusion attempt at any level of the lumbar spine;
4. Active systemic or local infection;
5. Known or documented history of communicable disease, including AIDS and HIV;
6. Active Hepatitis (receiving medical treatment within two years);
7. Active rheumatoid arthritis, non-controlled diabetes mellitus, or any other medical condition(s) that would represent a significant increase in surgical risk or interfere with normal healing;
8. Immunologically suppressed, or has received systemic steroids, excluding nasal steroids, at any dose daily for > 1 month within last 12 months;
9. Known history of Paget's disease, osteomalacia, or any other metabolic bone disease;
10. Osteopenia or Osteoporosis: A screening questionnaire for osteoporosis, SCORE (Simple Calculated Osteoporosis Risk Estimation), will be used to screen patients who require a DEXA bone mineral density measurement. If DEXA is required, exclusion will be defined as a DEXA bone density measured T score less than or equal to -1.0.
11. Morbid obesity defined as a body mass index > 40 kg/m2 or weight more than 100 pounds over ideal body weight;
12. Active malignancy. A patient with a history of any invasive malignancy (except non-melanoma skin cancer), unless treated with curative intent and there has been no clinical signs or symptoms of the malignancy for more than 5 years;
13. Current or recent history (within last 2 years) of substance abuse (e.g., recreational drugs, narcotics, or alcohol);
14. Pregnant or planning to become pregnant during study period;
15. Involved in study of another investigational product that may affect outcome;
16. History of psychosocial disorders that could prevent accurate completion of self reporting assessment scales;
17. Patients who are incarcerated.