Health watch: 3D printing brings new dimensions in orthopedics

Staff Writer
Columbus CEO
New Albany High School junior Aaron Westbrook with his 3D printer.

3D printing is helping improve outcomes while saving time and costs.

Use of 3D-printed prosthetics may not yet be routine, but orthopedic laboratories and surgical suites across central Ohio are already using the technology for precision, savings and better patient outcomes.

Orthopedic surgeons can now offer longer-lasting ankles, knees, hips and cranial repairs by using imaging to produce full-scale 3D models of a patient's bone structure and then rehearsing the precise incisions, pins and grids to support the repair and healing process. It not only saves time in the operating room, but also provides better fit and destroys less of the patient's existing bone.

Ohio State University and foot and ankle specialists at OhioHealth are forging ahead with 3D printing, training and education. They are part of medical 3D printing growth of 20-25 percent a year, while 3D printing overall is projected to grow from about $7 billion this year to $17 billion in 2020, according to consulting firm A.T. Kearney.

The Dean Lab at OSU Wexner Medical Center specializes in research and surgical applications for computer-assisted design and manufacturing and 3D printing of cranial and facial implants, with a team of more than 20 researchers, post-doctoral students and residents, says David Dean, an associate professor in the Department of Plastic Surgery for whom the lab is named.

Meanwhile, OhioHealth hosts the independent Orthopedic Foot & Ankle Center at its Westerville Medical Campus. The leader of the practice, orthopedic surgeon Greg Berlet, MD, is an advocate for 3D innovation, serving as co-editor of the bimonthly publication Foot & Ankle Specialist and training post-doctoral students in Columbus and globally.

Berlet uses his proprietary Prophecy process involving 3D imagery technologies and printing to make models for simulated surgery.

"It has changed the whole world in terms of ankle replacement in just five years. There will be no surprises when you get in there. There's no base stock (of ankle parts). Every individual patient's ankle is printed out individually" Berlet says.

A bone alignment off by just a few degrees can reduce effectiveness from 15 years to five, Berlet says. "For trauma surgeons, it sometimes feels like fixing Humpty Dumpty where bones are shattered, and it's not uncommon to have 10 or 12 pieces of bone and you have to put things back together," Berlet says. "Now we can make a 3D model and get a plan on how to re-build the joint before going to the OR."

Berlet relies on offsite printers and some engineering specialists to provide 3D-printed models, and the Dean Lab has two 3D printers.

"Some printers coming out now will be able to lay down polymer and metal-like color printing as opposed to black and white. After all, no one piece of the human body is made of one material," Berlet says.

Twenty years ago, Dean's work on human skull prosthetics involved averaging out physical measurements of human skull specimens. CAD/CAM models were limited to geometric shapes. But today's 3D imaging and high-resolution 3D printers have changed all that, he says.

The Dean Lab focuses on polymers friendly to human tissue, such as polypropylene fumarate, or PPF for short, which yields bio-friendly scaffolding material strong enough to support healing but absorbable and biodegradable inside the body without any toxic effect.

OSU's 3D printing work also extends to other specialties, including recent work by an inter-disciplinary team of surgeons and researchers-including Alex Farag, MD, a specialist in rhinology and skull base surgery, and Kai Zhao, an associate professor and biomedical researcher, both at OSU Wexner Medical Center. They use 3D imaging and 3D printer modeling to show air flow and blockage patterns in a patient's sinuses, and then they plot out surgeries in this vulnerable center for nerves of sight and smell within one millimeter of accuracy. Soon, OSU hopes to coordinate 3D printing availability for a wide range of disciplines.

"Three things changed the research," Dean says, reflecting on the accelerating technology. "It's big cheap hard disks, starting in the late 1990s, the PDF documents we have now instead of copying papers from the library, and-very recently-to be able to buy human cells."

Human stem cells-harvested from bone marrow, fat or amniotic tissue, not embryonic cells-help the scaffolds employed in ankle surgery send signals to the bone and blood that say, "Feed me and grow me," Berlet says, and today's high-resolution 3D printers make it possible.

All this innovation comes at a price for the 3D printing technology itself, the training and surgical planning time. But shorter time in anesthesia and in the operating room, along with more precise alignment of bone structures, makes a great case for cost savings during orthopedic procedures and long-term outcomes for many years to come, Dean and Berlet say.

"There's a revolution coming, but people are taking a long time to understand what it is," Dean says. "If you don't have to use the operating room as long, it's much safer and cheaper, and they can get another case in the operating room. Also, the (3D-printed) part fits the patient, rather than carve the patient to fit the part.

"There's a very big ship moving here, much like why we are driving gas cars, not electric cars," Dean adds. Ultimately, customized 3D-printed replacement joints will disrupt the market for off-the-shelf knees, hips and shoulders, he believes.

Printing the Future

Aaron Westbrook, a 16-year-old junior at New Albany High School, isn't waiting for the future. When his school acquired a 3D printer last year, Westbrook began experiments on prosthetics to extend his right arm, which ends a few inches below his elbow.

Energized and fascinated with the possibilities of 3D printing, Westbrook linked up with E-nable, founded by the Rochester Institute of Technology as a global network of individuals using 3D printers to create free 3D hands and arms for those in need of upper limb mobility and assistance.

The teen purchased his own Ultimaker 3D printer after raising funds through a Kickstarter campaign last year, and the printer has helped him refine new designs for his own arm. He'll tell his story of turning disability into empowerment at TEDxNewAlbany on April 2.

"I'm definitely into many different things, but this is my passion," Westbrook says. "I never had this opportunity growing up, and I wasn't connected to the community of other people like me. I got a traditional prosthetic from the Shriners' Hospital, which was wonderful, but not very practical or beneficial."

Those kinds of prosthetics cost $40,000 to $50,000 and don't provide the mobility and gripping motion he already has from his own 3D printed forearm and hand.

Although Rochester Institute of Technology is his No. 1 college choice, Westbrook says, "I see myself as more of an artist than an engineer. I like making something-whether that's making something for someone else or just being able to make it."

Beyond the actual technology and design process, his Alive With Five website provides visibility and insight to his work. "Especially since I have the blog aspect, I get a lot of reactions from people in need of devices or from people who want to help me out in some way. It's cool to be a middle man in a way for both groups."

The blog and his E-nable association led him to a project with a girl who belongs to the Nub Club of Central Ohio, for kids with missing limbs or limb differences. "I'm making her a prosthetic arm this spring," he says.

Mike Mahoney is a freelance writer.