© WHITNEY SALGADO
Ron Strang lay on his back and bent his left leg. “I could feel the difference right away,” recalls the 31-year-old ex-Marine.
The day before, Strang had undergone an experimental surgery to help repair a deep gouge in his quadriceps. He’d been injured in April 2010 while on foot patrol in Afghanistan’s Helmand Province, when a crude roadside bomb sent shrapnel tearing through his upper thigh. Ten soldiers were wounded in the blast, Strang the most grievously. A year later, even after numerous surgeries and skin grafts, he still couldn’t walk without his knee buckling. So he signed up to receive an experimental regenerative therapy.
In July 2011, Stephen Badylak, a tissue-engineering specialist at the University of Pittsburgh, transplanted a thin sheet of extracellular matrix ...
