Critical Bone Defect Improvement Device and Methods

Customized treatment for humans and canines
Bone Sleeve

Available for Licensing
TRL: 5

IP Status

US Patent Pending


David Prawel
Bernard Seguin
Connor Witt

Reference No: 2021-036
Licensing Manager

Steve Foster

At a Glance

Researchers at Colorado State University have developed a novel limb sparing technique based on the current standard of care and a bioreplaceable endoprosthetic design to protect and enable a highly osteogenic scaffold. This scaffold integrates with FDA approved fixation devices to support native bone growth without loss of load-bearing ability. This new method could be used in veterinary or human orthopedic settings, to heal large critical bone defects with better long-term outcomes and osteointegration.



Critical bone defects are classified as severe trauma to a bone, typically a limb, that won’t heal spontaneously. Critical bone defects occur with unfortunately high frequency in both human and veterinary patients, due to cancer and external trauma. Most wounds received by combat veterans are to the extremities, with many of these wounds considered “critical” in size. Limb-sparing procedures are considered the standard of care in humans, which involve implanting large metal plates that are permanent to provide mechanical support necessary for the wound. However, this approach can cause lifelong issues, and often presents complications such as screw loosening, plate fracture, and infection, with complication rates as high as 48% in humans and over 90% in dogs.

Poor healing of these critical bone defects remains one of the biggest challenges in human and veterinary orthopedic medicine, often resulting in reoperations, poor functionality, poor long-term outcomes, and limb loss6, causing significant clinical and economic cost.


The novel limb sparing technique includes both a scaffold and traditional, FDA approved fixation devices. The scaffold is a 3D printed biomaterial, and allows for osteogenic material to enhance critical wound healing, without a loss of load-bearing and mechanical strength due to the coupling with existing fixation devices. The proposed device and methods offer a degradable, tunable fixation device to heal critical wounds, that does not result in a permanent metal implant.

Animal studies are ongoing to test in vivo efficacy, and ultimately, further develop our method to enable complete bone healing and removal of all fixation devices, and easily translate to human orthopedic medicine applications. Methods and materials are proprietary, please contact our office for more information.

  • Enhanced osteogenic properties increases bone growth and healing
  • Scaffold section biodegrades, allowing for endogenous bone growth in wound healing
  • Endogenous wound healing will hopefully replace
  • 3D printing allows for customized fit of the scaffold to patient specific sizing needs
  • Large bone defect treatment
  • Canine orthopedic treatment
  • Human orthopedic treatment

Last updated: June 2022