Pin-up boy: Isaac Jones with parents Lisa and Troy and, inset, how he looked before his skull was taken apart and put back together. Picture: JAYTOWN

GETTING back on the bike after a fall has taken on a whole new meaning for Isaac Jones -- and for his parents it couldn't be better. Just weeks after having his deformed skull literally cut off, turned into a jigsaw and replaced as a brand new head, one-year-old Isaac is tackling life head-on.

When he sneaked away from his mum Lisa and jumped on his trike, only to fall off and hit his head just weeks after the remarkable operation, she thought her worst fears were coming true. But instead her horror turned to joy when she realised just how strong Isaac's head had become, and he is now preparing for a new role as the happy and healthy pin-up boy for next year's Good Friday Appeal.

"When he fell off I was doing something else and I heard this crash bang thump and he was lying there crying and I just picked him up and two minutes later he was pushing off my knee trying to get down and have another go," Ms Jones said. "He is just so super happy. He is full of beans and fun.

"When we went back for the second week check they said his head was fine and it was time to be a little boy. We just said `are you sure?' "The first couple of weeks were tough, but when you look at him now he is just happy, full of energy, learning new things and wanting to learn more new things. And medically heis good."

The Royal Children's Hospital's pioneering surgeons Prof Tony Holmes and Dr David Chong rebuilt Isaac's elongated head in the days before his first birthday.

The surgery was intended to relieve pressure from Isaac's squashed brain to developmental delays, and tests since the operation show his intellect, speech and coherence is at an 18-month level. Because he has always had a bigger head it has slowed down his movement, but the curious Isaac is rapidly learning to walk.

A stomach infection as he was about to leave hospital meant it took Isaac a little while longer than planned to return home to Shepparton, and for the first four weeks he would only sleep lying on his mum and dad's chest while being cuddled. But his dad Troy said a month after the operation everything "just clicked".