3D Bioprinting Could Be The Next Big Thing In Knee Surgery
February 13, 2014

Cartilage Produced From 3D Printer

Rebekah Eliason for redOrbit.com - Your Universe Online

Amazing advancements in the technology of 3D printing have been made at Scripps Clinic in La Jolla. Dr. Darryl D'Lima along with his colleagues report they have discovered a process to “bioprint” cartilage tissue.

D’Lima is responsible for the design of a prototype bioprinter that will print living cartilage. Adapted from a Hewlett-Packard inkjet printer, the bioprinter spews out both cartilage progenitor cells and a biocompatible liquid that will congeal in the presence of ultraviolet light. In addition, the device can print bone cells necessary to deposit where cartilage attaches to bone.

The goal of this research is to design technology that will truly fix knee injuries from cartilage damage and injury. This tough, slippery tissue functions as a cushion between joints, but it does not often regenerate. People suffering from arthritis or a knee injury understand that a lack of cartilage that leads to bone grinding against bone causes excruciating pain.

Currently, the best medical option for lack of cartilage is to implant an artificial knee joint, which is painful and not always permanent. Despite the problems with knee replacements, there is still a multibillion-dollar market for the procedure. Because of the vast amount of aging baby boomers and levels of obesity, the market is projected to continue growing. In 2010, the global knee replacement market made $6.9 billion and is projected to grow to $11 billion by the year 2017.

Although D’Lima says it will take several more years of work before his new technology can be used in people, he indicates the main scientific challenges have been conquered. All that is left is the engineering. Currently the cartilage is printed in a laboratory, but D’Lima envisions a system that prints the material directly into patients on the operating table.

If the cartilage were printed directly into the knee joint, it would ensure a closer fit than cutting lab-grown cartilage to the correct size.

The droplets of cell-containing material are extremely small at about one picoliter, which is one-billionth of a liter. A drop that tiny is small enough to fill in microscopic irregularities in a person’s cartilage or bone.

“It would be the equivalent of filling a pothole,” he said. “It would automatically fill the defect as you’re printing it. You’re getting a fairly good mechanical integration into the tissue, which is very difficult for us to do when we do traditional transplants.”

An additional advantage is that surgery could be performed as needed.

“We wouldn’t have to store something off the shelf,” D’Lima said. “We wouldn’t have to prepare it in advance, if it takes three to six weeks to make the tissue and plan for the day of surgery. All of this would be done on the day of surgery, on demand.”

Since there is no printer that exists yet that can print directly into a patient, D’Lima is continuing this research by consulting with the company Invetech, which has previously designed a bioprinter that is used by San Diego’s Organovo.

D’Lima explained that cartilage is easier to bioprint than other tissues due to its lack of blood vessels. “It’s complex enough that you need technology like 3D printing, but at the same time it’s not so complex that it’s extremely challenging,” D’Lima said.