In the dynamic world of surgical innovation, bone graft substitutes have saturated the market, presenting surgeons with a variety of choices.
This abundance of alternatives, spanning from traditional cadaveric allografts to synthetic substitutes, provides numerous options often without clear literature justification.
But when faced with all these autograft substitution options, it begs the question: Should you settle for a substitute when the gold standard is available without the risks of traditional harvesting?
Autologous cancellous bone graft has been utilized and documented to be effective in peer-reviewed literature, authored by surgeons without any related potential conflict of interest, for a variety of applications, for well over a century!
No autograft substitute (including BMO-2) can make a similar claim.
Most of the published literature associated with bone graft substitutes has been relatively recent in nature, often authored by surgeons and published in journals with a potential of conflict of interest, and associated with studies of relatively limited surgical application and in many instances having insufficient power of participants to form a statistically significant conclusion.
Autologous Cancellous Bone Graft Vs. Alternatives
Autologous Cancellous Bone:
Harvested from the patient’s own body, it boasts a high success rate due to its comprehensive constituents and minimal manipulation. This graft material has no risk for immunologic rejection and it contains osteogenic as well as hematopoietic cells (in a humeral relationship that promotes osteogenesis) for bone formation, graft incorporation, and host site remodeling. Autologous cancellous bone is considered the gold standard for these reasons and while past harvest effort and subsequent harvest site morbidity led to the development of bone graft substitutes, minimally invasive techniques (including percutaneous harvesting) have provided reasons for surgeons to reconsider its utilization as their primary option in bone graft surgery.
Allografts:
Sourced from a cadaveric donor, are convenient and widely available in a variety of forms. Most allograft products contain demineralized bone matrix or DBM, derived from cortical bone. DBM’s primary function is osteoinduction and various additives are used to supplement this primary function (including cancellous chips for osteoconduction and mesenchymal stem cells for osteoproliferation), however, there is little to no compelling evidence to indicate that these additives enhance DBM alone, for bone proliferation. Many of these proprietary allografts are relatively costly, and thus cost justification cannot be based upon clinical evidence.
Synthetic Substitutes:
These man-made materials, stimulate bone formation in animal models, but there is no compelling statistically significant clinical evidence to show their superiority to autologous grafts or allografts. Bioglass is a family of bioactive glasses composed of silicon dioxide, sodium oxide, calcium oxide, and phosphorous pentoxide. This material yields a surface pore structure, 5–20 nm, with the ability to induce apatite formation. Bioglasses are generally structurally fragile.
Bone Enhancers:
Platelet rich plasma (PRP) and bone morphogenetic proteins (BMPs) are used to boost the graft’s bone growth capabilities. PRP requires harvesting of peripheral blood and subsequent processing with relatively expensive equipment, without clear benefit. BMP-2 has been demonstrated to be both a strong inducer of bone formation and an inflammatory progenitor, that can result in host site bone resorption, implant subsidence, heterotopic bone, and adjacent neuritis (as well as carrying the potential for immune-sensitization, a contraindication in women considering future pregnancies). BMP-2 is black box labeled for use in cervical fusions. BMP-2 is a costly bone graft substitute and cost justification can represent a barrier to its use.
Other Bone Graft Substitutes:
Other bone graft substitutes include xenografts (materials taken from animals), growth factors (other than BMP), and bone marrow aspirate (BMA). These materials are less commonly used than autografts, allografts, or synthetic substitutes and have limited evidence to support their effectiveness.
The Science Behind the Success of Autologous Cancellous Bone Graft
For a grafting material to be effective, it must possess three core properties: osteoinduction, osteoconduction, and osteogenesis. Autologous cancellous bone graft, with its origins in the patient’s own bone, is naturally replete with these attributes, offering a uniquely favorable environment for bone healing and integration.
- Osteoconduction: This is the scaffold provided by the graft, and the trabecular bone architecture in autologous cancellous bone offers an optimal framework for new bone formation.
- Osteoproliferation: Derived from the patient’s mesenchymal stem cells, this graft has an intrinsic capability to promote bone regeneration. Unlike allograft that is “doped” with expanded mesenchymal stem cells, autograft’s osteoproliferative cells are not displaced from their native locations in the bone matrix.
- Osteoinductivity: The presence of native growth factors in autologous cancellous bone facilitates the differentiation of these stem cells into bone-forming cells.
Addressing Harvesting Challenges: Embracing Minimally Invasive Techniques
Traditional methods of harvesting autologous cancellous bone have often led to donor site morbidity. Soft tissue stripping, large cortical access defects, and open harvesting contributed to post-operative pain, excessive blood loss, increased infection risks, and even abdominal herniation. Certain harvesting techniques can inadvertently diminish the graft’s quality, due to graft manipulation and desiccation.
A Revolution in Bone Harvesting
The COREX Minimally Invasive Bone Harvester was conceived by a surgeon and designed in collaboration with biomechanical engineers, to address the concerns of autograft harvesting. The design effort was intended to provide an expedient means of percutaneously harvesting cancellous bone, without the need for any supplemental instruments. In addition, the design priority was to optimize patient safety through a manual instrument that allowed for cancellous bone collection with minimization of risk for cortical breaching. Cortical breaching and cylindrical cancellous bone retention through patented mechanisms.
Minimally Manipulated Autologous Cancellous Bone: The COREX MIS system ensures the highest quality graft material by preserving the natural architecture of the bone. This is critical for maximizing fusion potential, giving your patients the best chances for rapid and effective healing.
Enhanced Patient Safety: The cutting-edge, precision-engineered minimally invasive technology of COREX can reduce surgical trauma. This means fewer post-operative complications and a smoother recovery process for your patients.
Streamlined Procedures: Time is of the essence in the OR. With COREX, surgeons can harvest bone efficiently without any compromise on quality, ensuring that you maximize your OR time and focus on what truly matters – delivering top-notch patient care.
Experience First Hand
The all-in-one, autonomous MIS harvesting system, including wholly percutaneous harvesting, allows for quick collection of minimally manipulated autologous cancellous bone.
The result? Streamlined procedures and optimized fusion efforts.
We invite you to join us at NASS this October to get hands-on experience and see COREX in action.
Not attending NASS, contact us today to schedule a demo or receive your free sample.
