Fix a Broken Bone

I've only broken a bone once (knock on wood) but this sounds like a development that could help a lot of people. Unfortunately, it'll be at least five years before human trials begin.

From the BBC...

Doctors may soon be able to patch up damaged bones and joints anywhere in the body with a simple shot in the arm.

A team at Keele University is testing injectible stem cells that they say they can control with a magnet.

Once injected these immature cells can be guided to precisely where their help is needed and encouraged to grow new cartilage and bone, work on mice shows.