Singer's doctors advise him to take time off to heal broken shoulder.By Gil Kaufman Aerosmith's Steven Tyler Photo: Kevin Kane/ WireImage Aerosmith canceled the rest of their summer tour with ZZ Top on Thursday as a result of injuries sustained by singer Steven Tyler, 61, last week at a gig in Sturgis, South Dakota, during the annual Sturgis Motorcycle Rally. Vamping for the crowd while some sound issues were being worked out at the August 5 show, the veteran frontman known for his high-energy performances fell off the stage at the gig and suffered a broken shoulder and a gash in his head that required 20 stitches. Tyler was airlifted from the venue and later flown to Boston to consult with his personal doctors about the injuries.