New Hope for Knees: 3D Printing and Proteins

Researchers have found a way to regenerate torn or damaged knee menisci using 3D printing and implanted recombinant human proteins.

According to their study in Science Translational Medicine, the technique has been successfully carried out in sheep, which have knees similar to those of humans. It starts with an MRI of the healthy meniscus in a patient’s undamaged knee. A 3D printer then produces a scaffold (in about 30 minutes) that’s essentially an exact replica, using polycaprolactone, a biodegradable polymer used in sutures.

The scaffold, when inserted into the damaged knee, is infused with connective growth factor (CTGF) and transforming growth factor β3 (TGFβ3). When released in a pre-specified order, the growth factors attract existing stem cells from the body and induce them to form meniscal tissue. Eventually, the scaffold dissolves and is absorbed. In sheep, the entire process takes about 4 to 6 weeks.

“We envision that personalized meniscus scaffolds, from initial MRI to 3D printing, could be completed within days,” says study leader Jeremy Mao, DDS, PhD, of the Columbia University Medical Center in New York. The scaffolds could then be shipped to clinics and hospitals within a week. … (Read more)