Single-Armed Use of ViviGen Cellular Bone Matrix in Patients Undergoing Posterolateral Lumbar Surgery

A Prospective, Single Arm Study of Patients Undergoing Posterolateral Lumbar Fusion (Without Interbody) Supplemented With ViviGen Cellular Bone Matrix

This is a prospective, single-arm post market study of patients to assess fusion in one or multiple continuous levels of the lumbosacral spine (L1-S1) using ViviGen Cellular Bone Matrix. All subjects will be followed out to 24 months for final assessment.

Lumbar spine fusion rates can vary according to the surgical technique. Although many studies on spinal fusion have been conducted and reported, the heterogeneity of the study designs and data handling make it difficult to identify which approach yields the highest fusion rate. Traditional posterolateral intertransverse fusion (PLF) still remains a good procedure with acceptable fusion rates for most degenerative conditions. For solid fusion, PLF can be combined with interbody fusion to circumferentially stabilize the relevant segment, even though it is unclear whether this improves fusion rates.

A bone graft or bone graft substitute is required to produce the fusion and can be implanted on its own, in the posterolateral gutters, or contained with an interbody device using either a posterior or anterior approach. Spinal laminectomy is most often the largest generator of bone graft product due to the nature of the procedure. The current gold standard is autograft bone, in which tissue is harvested locally or from the iliac crest and is then placed at the site. However, local bone graft may be relatively limited and harvesting at the iliac crest can easily lead to significant morbidity. Complications such as inflammation, infection, and chronic pain may outlast the pain of the original surgical procedure.

Autograft is the gold standard because it possesses all of the characteristics necessary for new bone growth-namely, osteoconductivity, osteogenicity, and osteoinductivity. Allograft tissues are alternatives to autografts and are taken from donors or cadavers, circumventing some of the shortcomings of autografts by eliminating donor-site morbidity and issues of limited supply. Osteoconductivity refers to the situation in which the graft supports the attachment of new osteoblasts and osteoprogenitor cells, providing an interconnected structure through which new cells can migrate and new vessels can form. Osteogenicity refers to the situation when the osteoblasts that are at the site of new bone formation are able to produce minerals to calcify the collagen matrix that forms the substrate for new bone. Osteoinductivity refers to the ability of a graft to induce nondifferentiated stem cells or osteoprogenitor cells to differentiate into osteoblasts. Using the 2 basic criteria of a successful graft, osteoconduction and osteoinduction, investigators have developed several alternatives, some of which are available for clinical use and others of which are still in the developmental stage. Many of these alternatives use a variety of materials, including natural and synthetic polymers, ceramics, and composites, whereas others have incorporated factor- and cell-based strategies that are used either alone or in combination with other materials.

Inclusion Criteria:

• Subject is scheduled to undergo a single or multilevel posterolateral spinal fusion surgery using ViviGen Cellular Bone matrix
• Subject must be over the age of 18 years old
• Subject has been unresponsive to conservative care for a minimum of 6 months.
• The subject must in the investigator's opinion, be psychosocially, mentally, and physically able to fully comply with this protocol including the required follow-up visits, the filling out of required forms, and have the ability to understand and give written informed consent.

Exclusion Criteria:

• Subjects requiring additional bone grafting materials other than local autograft and ViviGen Cellular Bone Matrix will be excluded from this outcomes study.
• Subject has inadequate tissue coverage over the operative site
• Subject has an open wound local to the operative area, or rapid joint disease, bone absorption, or osteoporosis.
• Subject has a condition requiring medications that may interfere with bone or soft tissue healing (i.e., oral or parenteral glucocorticoids, immunosuppressives, methotrexate, etc.).
• Subject has an active local or systemic infection.
• Subject has a metal sensitivity/foreign body sensitivity.
• Subject is morbidly obese, defined as a body mass index (BMI) greater than 45.
• Subject has any medical condition or extenuating circumstance that, in the opinion of the investigator, would preclude participation in the study.
• Subject is currently involved in another investigational drug or device study that could confound study data.
• Subject has a history (present or past) of substance abuse (recreational drugs, prescription drugs or alcohol) that in the investigator's opinion may interfere with protocol assessments and/or with the subject's ability to complete the protocol required follow-up.
• Subjects who are pregnant or plan to become pregnant in the next 24 months or who are lactating.
• Subject is involved in or planning to engage in litigation or receiving Worker's Compensation related to neck or back pain.
• Osteoporosis (per the investigator's diagnosis or per a T-score > 2.5 standard deviations below the mean for a young, healthy adult) that may prevent adequate fixation of screws and thus preclude the use of a pedicle screw system.
• Subjects who have a known or suspected allergy to any of the following antibiotics and/or reagents: Gentamicin Sulfate, Meropenem, Vancomycin, Dimethyl Sulfoxide (DMSO), and Human Serum Albumin (HSA);
• Immune compromised subjects
• Known sensitivity to device materials
• Subject is a prisoner.