Older age catching up with the U2 lead singer? Perhaps. The 50-year old Bono injured his back during rehearsals and underwent emergency surgery today in Munich, two weeks before U2 is set to kickoff the North American leg of their “360 Degree” world tour in Utah. If you have tickets to any U2 concerts in the near future, you should keep an eye out for Bono’s recovery. U2’s manager, Paul McGuinness,  has already voiced hints that the injury could cause postponements of future shows. “It’s unfortunate that we’re inconveniencing fans,” he said in an audio message. “We will make plans to reinstate these dates as soon as possible.”