A new nanofiber gel material that stimulates natural cartilage growth in damaged joints may be a more effective alternative to microfracture for knee repair, according to the Northwestern University researchers who developed the material.

In a study published in the Proceedings of the National Academy of Sciences, lab tests in animals show that, when injected into damaged joints, the liquid, bioactive nanomaterial stimulates stem cells in the bone marrow to produce natural cartilage with better results than the microfracture procedure alone, in which small holes are drilled into the bone to stimulate cartilage growth.

Microfracture "tends to produce a cartilage having predominantly type 1 collagen, which is more like scar tissue," says Ramille N. Shah, assistant professor of orthopedic surgery at Northwestern's Feinberg School of Medicine. The nanofiber gel developed by Ms. Shah and colleagues has been shown to produce cartilage containing the smoother type II collagen.

Irene Tsikitas