Autologous Bone Graft Harvesting With the Corex Device

“Not All M.I.S. Harvesting Methods Are Alike”

James F. Marino, M.D., FAAOS (Founder and Medical Consultant) Trinity Orthopedics LLC San Diego, CA

Disclosures:

The Corex™ Device is manufactured and sold by Trinity Orthopedics LLC
James Marino is the founder of Trinity Orthopedics LLC
James Marino is an investor in Trinity Orthopedics LLC
James Marino is a paid consultant of Trinity Orthopedics LLC
James Marino is retired from clinical practice, after ~40 years in practice and used the Corex™ device on numerous occasions harvesting from the iliac crest and proximal tibia. He also has harvested with the Corex™ device from various sites in cadaveric demonstrations.

Our Objective – Bone Formation and Subsequent Functional Remodeling at the Host Site

Corex™ Device by Trinity Orthopedics, LLC

No other bone graft or bone induction material has greater than 100 years of peer-reviewed journal articles demonstrating efficacy in a wide variety of applications (experimental and clinical), with very few authors having any potential conflict of interest.
No other bone graft or bone induction material is as rapidly incorporated into the host site. “Neovascularization occurs within the graft as early as 2 days after implantation; as it continues, there is a repopulation of the marrow spaces with primitive MSCs of both donor and recipient origin” The Biology of Bone Grafting, Khan et al, J Am Acad Orthop Surg 2005;13:77-86

Historical donor site complication levels are commonly cited by various parties promoting alternative bone graft material as relevant evidence of the complications of autologous bone grafting. This would be analogous to equating open arthrotomy knee surgery to arthroscopic knee surgery or open laparotomy procedures to laparoscopic procedures.
MIS techniques in autologous bone graft harvesting have dramatically altered the type and frequency of donor site morbidity, yet many practitioners within the relevant disciplines have a preconceived understanding based upon historical data associated with open harvesting techniques.
MIS bone graft harvesting is generally percutaneous (or via a very minimal incision), performed through a small cortical defect, and does not involve muscle or tendon stripping.
Yet not all MIS autologous cancellous bone graft harvesting methods are alike.

Avoid accidental or excessive cortical bone violation utilizing controlled manual or power cortical breaching
Utilize bone harvesting means that provides for proprioceptive feedback to reduce the risk of unintended cortical breaching Manual rather than powered cancellous bone harvesting
Provide for multiple redirected passes through a single cortical window
Provide a cancellous capture mechanism that minimizes distortion of native architecture and preserves cellular content Avoids unnecessary morcellation and suction that dramatically alter the graft
Avoids cancellous bone desiccation and minimizes handling 6) Employs a procedurally efficient, single patient dedicated device without the need for supplemental instrumentation

Optimize host site for graft incorporation – well vascularized “bleeding” bone surface, debride fibrocartilaginous and devitalized tissue from host bone graft contact surfaces
Optimize condition of transferred graft for host site integration and bone proliferation – avoid unnecessary cancellous bone morcellation, desiccation, or cellular alteration
Optimize graft-host contact – place graft in intimate contact with host bone surfaces
Minimize donor site morbidity – utilize MIS principles for harvesting, percutaneous harvesting if possible

Musculoskeletal Surgeons are often regarded as “carpenters of the body”, but this characterization fails to recognize the vitality of the structures is as or more critical than their configuration.
Optimizing blood supply and preservation of cell vitality in bone grafting is often under appreciated.
While allografts and bone graft substitutes are devitalized, one of the distinct advantages of autogenous cancellous bone graft, is the potential to preserve osteo-proliferative cells within the graft.

Unnecessary morcellation of harvested cancellous bone distorts architecture thereby delaying revascularization and ultimately requiring “knitting together” fragments at the recipient site
Autograft harvesters that displace or separate the cellular element from their native positions within the cancellous bone results in diminished cellular viability and differentiation specificity.
Reassociating the cellular elements with the harvested cancellous bone does not restore osteo-synthetic function of graft cells

Single patient use, sterile packaged all in one harvester
Manual deployment provides for proprioceptive feedback, increasing safety
Cortical breaching through an integral and patented component that limits depth of penetration
Cancellous trephine with castellations and a beveled projecting surface to microfracture the perimeter of the cylindrically captured cancellous bone
Patented capture mechanism, allows for securing the cancellous bone without distorting the architecture or displacing the cellular elements
Greater than 35,000 clinical uses (since 2007) without a single serious reported complication (i.e. no MAUDE reporting of a serious or life- threatening complication with use)