Sprint superstar Usain Bolt has ruled out competing for the rest of 2010 after suffering a back injury.

The 23-year-old suffered his first 100m final defeat in two years when he was easily beaten by Tyson Gay on 6 August at Stockholm's Diamond League meeting.

"2011 and 2012 are very important championship years and I hope to be back fully fit and healthy," said Bolt, after a medical examination in Germany.