With a focus on helping soldiers who have suffered combat wounds, John Szivek — a biomedical engineer and professor of orthopedic surgery at the University of Arizona — is looking at the ways in which stem cells can be integrated with 3D printing technologies to help heal broken bones.
Unlike the injuries sustained during day-to-day civilian activities, combat injuries are typically more serious and don’t always allow the bone to return to its original state. This can lead to lingering side effects and long-term issues, as well as bone defects. Although surgically grafting pieces of bone from cadavers can provide a solution, these grafts typically fail within a year, requiring repeat surgeries — potentially leading to life-long challenges for veterans.
However, Szivek recently received a five-year, $2 million grant from the U.S. Department of Defense to study approaches that could prove more reliable than the previously mentioned allografts.
Szivek’s plan is to 3D print plastic, bone-shaped frames called scaffolds. These implants will replace broken or excessively damaged bone segments. These scaffolds will then be filled with calcium and stem cells to assist in repairing, and, in some instances, regrowing, the bone. Szivek and his team have used similar techniques in the past to attach new cartilage when repairing damaged joints.
Pilot projects have shown significant bone quality improvement in about three months.
Next steps will include speeding up that process and providing validation in obtaining FDA approval. And to help improve recovery times, the team will test the impact of exercise early in the healing process, as some theories state that exercise can speed up bone growth. The 3D-printed implants will be embedded with tiny sensors that can wirelessly transmit exercise activity.
These sensors will analyze how much weight is being put on the scaffold and for what length of time, allowing the researchers to evaluate the effectiveness of physical activity in the recovery process.