A torn meniscus is among the most common afflictions suffered by athletes who make sudden stops and turns, such as NBA star Blake Griffin, whose injury forced him to pull out of the Olympics.
The usual response is to remove the torn portion of the tissue, to prevent further painful tearing. But because the meniscus cushions the knee joint, removing part of it can lead to osteoarthritis.
A possible treatment, say many in the field of bioengineering, is to replace the torn portion with new tissue, grown from the patient's own cells. Researchers at the University of Pennsylvania's Perelman School of Medicine recently reported a promising advance in that direction, spinning webs of polymer fibers to serve as a "scaffold" for new cells.