"This is, in my opinion, in a whole different league than tissues that have been engineered before," says University of Pennsylvania orthopedic bioengineer Robert Mauck, who was not involved in the study. "This is essentially opening the door for replacement of a tissue that's central to humans walking."
The current course of treatment for degenerative disks includes painkillers, physical therapy, and steroid injections to ease inflammation. As a last resort, patients can undergo surgery that fuses together two vertebrae, removing the need for a disk between them but also limiting the flexibility of the back. Within the past 5 years, artificial disks have also become an option. Current disk implants are made of metal or plastic, however, and have limitations. They don't provide a full range of spinal movement, and they can wear out as they rub against vertebrae.
Hoping to eliminate those pitfalls, Lawrence Bonassar, a biomedical engineer at Cornell University, and his team created an artificial scaffold shaped like a disk, with collagen on the outside to provide structural stability and a gel in the center. Then they added two types of living disk cells taken from a rat's spine: one from the outer edges of a disk, which they added to the collagen, and another type found in the center of disks, which they seeded into the gel. For 2 weeks, they let the cells grow around the scaffold, creating a living disk and taking over both parts of the artificial scaffold. Then they surgically replaced a spinal disk in a rat's tail with the new implant. More
