
The writer H. L. Mencken quipped that conscience was a mother-in-law who never left. Sam Onukuri can say the same thing about inspiration, and he means it literally.
Onukuri and his team at Johnson & Johnson’s 3D Printing Center of Excellence are developing ways to 3D-print customized surgical tools and implants — including those for patients like his mother-in-law, who had both of her knees replaced. “If there was a customized 3D-printed knee available then, I believe her pain and the recuperation time could have been reduced,” he told a company blog. “Through 3D printing technology, we can print exactly what the patient needs to replace the degraded bone. The implant can be made based on a CT or MRI scan from thousands of miles away.”
Earlier this year, Onukuri, a mechanical engineer specializing in metallurgy, and Joseph Sendra, the global vice president for manufacturing, engineering and technology at J&J, spent time at GE Healthcare’s advanced manufacturing lab in Waukesha, Wisconsin, which is stocked with 3D printers, robots and other advanced technology. The additive manufacturing industry, a catchall term that includes 3D printing, is quickly maturing, and both companies want to stay in the vanguard of the field by sharing insights. “To make products now, we have large factories that require a significant investment,” Sendra says. “With 3D printing, we can potentially move manufacturing to a very small footprint, doing the same thing closer to the customer. That means products do not need to be shipped as far, and there’s a faster turnaround.”

Above: “With 3D printing, we can potentially move manufacturing to a very small footprint, doing the same thing closer to the customer,” says Joe Sendra of Johnson & Johnson. Top: “If there was a customized 3D-printed knee available then, I believe her pain and the recuperation time could have been reduced,” says J&J’s Sam Onukuri. Images credit: Johnson & Johnson.
One of the benefits of additive manufacturing technologies is that they can print customized solutions for patients — say, knees — directly from a computer file, layer by layer. When people have their knees or hips replaced today, Onukuri says, doctors typically have an option of five or six implants of different sizes, and a set of instruments that go with them. “Physicians make every effort to find the implant that fits best,” he says. “But it’s never a perfect match, and the same is true for the tools. As a result, the surgery takes longer — and so can healing and recovery — and the fit may not be perfect.”
3D-printed instruments or implants based on patient scans can achieve an exact fit for the joint. In addition, the specific surgical tools needed for the surgery, which tend to be complex, can be 3D-printed too. “With additive technology we can really transform the whole area,” Onukuri says. “Through our collaborative efforts with companies like GE, we will definitely get there.”
In Waukesha, Onukuri was also working on problems like “bioprinting,” which is using 3D printing to produce tissues that can replace or augment damaged organs. Bioprinted tissues or organs can be also used for drug testing and screening, eliminating the need for humans or animals in clinical trials. “J&J is interested in metals, polymers, ceramics and electronics 3D printing along with bioprinting, so there are a range of opportunities for collaboration,” Onukuri says.
But Onukuri and his counterparts at the GE Healthcare lab are not just changing the manufacturing process. They are also changing minds. “Design for additive manufacturing is different than design for traditional manufacturing,” says J&J’s Sendra. “It gives you the ability to consider many more solutions than you had before. But every engineer can’t think that way, and we have to teach them that there’s a difference. They need to look at the problem from a new point of view.”
Sendra says that 3D printing, though three decades old, is only now beginning to show its full potential. “What’s different now is the convergence of the additive technology and computing power with the science that unlocks capabilities,” he says. “It allows you to envision a reality and a solution that was previously unimaginable.”

A 3D-printed model of a human heart based on an image acquired by a CT scanner. GE engineers are looking for ways to convert data from GE Healthcare’s imaging machines into digital files that can be printed. The models could one day help doctors prepare better for surgery. Images credit: GE Reports.