Kids and bikes go together like peanut butter and jelly. It’s a natural combination. There they go—racing in the fresh air, laughing and burning off excess energy. But even with helmets and adult supervision, accidents can happen. And even the simple accidents can become dangerously serious. Just ask Matthew and his family.

Matthew took a tumble off his bike in late September 1999. He and his nine-year-old identical twin brother, Ken and some friends were having fun on their bikes when Matthew "hit a bump weird and landed on the handle bars."

Bruce, his dad, was there. "I went over to him," says Bruce, "and he was curled up, complaining that he could not breathe. He said he had a pain in his stomach, so, I lifted up his shirt expecting to see a bruise or some bleeding. But, there weren’t any marks at all. I assumed that he just got the wind knocked out of him."

But Matthew’s pain worsened, and his parents called an ambulance. The seriousness of Matthew's injury did not become apparent until a short time later when he was examined in the emergency room at Children’s Hospital.