Mechanical engineers have created a 3D-printed femur that could assist doctors in preparing for surgeries aimed at repairing bones and treating bone tumors. This research, which concentrated on the central part of the bone, sets the groundwork for 3D-printing specifications for a femur that can be used in biomechanical testing. However, the researchers indicated that further studies are required before this technology can be widely adopted.
Mechanical engineers at the University of Texas at Dallas have developed a 3D-printed femur that may aid doctors in preparing for bone repair surgeries and in creating treatments for bone tumors.
These engineers collaborated with orthopedic surgeons from UT Southwestern Medical Center and published their initial findings regarding the 3D-printed thigh bone on August 5 in the Journal of Orthopaedic Research.
This study, which zeroed in on the midsection of the bone, establishes the printing guidelines for a femur intended for biomechanical experimentation. Researchers emphasized that more research is necessary before this technology becomes widely available.
To evaluate and confirm new surgical implants and methodologies, surgeons conduct biomechanical studies using donated cadavers or commercially produced synthetic bones. These resources assist them in determining effective surgical fixation methods and predicting how the bone will react. However, synthetic bones can be pricey, often require significant time to procure, and typically do not provide patient-specific solutions.
Researchers from UT Southwestern reached out to Dr. Wei Li, a 3D-printing technology expert at UT Dallas, two years ago to work together on a more economical and efficient alternative for orthopedic biomechanical studies.
“Surgeons need to understand the bone’s geometry to plan for surgeries,” stated Li, who is an assistant professor of mechanical engineering in the Erik Jonsson School of Engineering and Computer Science, and the main author of the recent paper. “Thanks to 3D printing, we can create a femur sample that mirrors the exact geometry of the femur in the patient’s body.”
Through a process of trial and error, UTD doctoral student Kishore Mysore Nagaraja created several versions of the femur. Working in Li’s Comprehensive Advanced Manufacturing Lab, he performed numerous tests on each artificial bone to assess their mechanical performance and material characteristics, ensuring that the samples closely resembled real femurs.
“This collaborative experience is the best opportunity a student could wish for,” said Mysore Nagaraja, who plans to graduate in December. “Receiving feedback on my testing research directly from the surgeons who will be utilizing it provides great validation for our work.”
The replica bone is crafted from polylactic acid, an affordable, biodegradable polymer that is commonly used in 3D printing. The design, which mimics the femur’s midsection, measures nearly 8 inches in length and almost 1 inch in diameter. It performed comparably to a human femur during biomechanical tests, with researchers estimating that each 3D-printed femur costs $7 to produce.
Li noted that 3D-printed bones could have numerous applications. For instance, the polymer might substitute for other materials used in bone repairs, like titanium. Researchers might also print tumors on these 3D bones to evaluate treatments or use the replicas to aid in the development of human bone tissue.
Key researchers from UT Southwestern included Dr. Robert Weinschenk, an orthopedic oncology surgeon and the first author of the study, along with Dr. Richard Samade, a hand and upper extremity surgeon who oversees a 3D-printing lab. Both are assistant professors of orthopedic surgery with secondary roles in biomedical engineering; Samade also has a secondary role in plastic surgery.
“I contacted Dr. Li and his team, and this has fortunately developed into a fantastic collaboration,” Weinschenk remarked. “With the surgical expertise and engineering experiences that Dr. Samade and I have, combined with Dr. Li’s exceptional knowledge in mechanical testing and his impressive resources, our combined team is well-equipped to address these challenges.”
Other contributors included former UTD student Faiqa Alam BS’23 and Dr. Blaine Oldham, who graduated from UT Southwestern in May.
