Miami Dolphins 10/09/2007 8:03 AMThe Palm Beach Post reports if he's like most people who have suffered two severe concussions in 13 months, Dolphins QB Trent Green won't return to the field for quite some time, a leading authority on sports-related concussions said Monday. Dr. Robert Cantu hasn't examined Green but expects him to experience symptoms for several weeks from the concussion he sustained Sunday against Houston. "The fact that he suffered prolonged symptoms the last time and a severe concussion this time doesn't bode well," said Cantu, a Boston neurosurgeon whose concussion grading system is one of the most widely used in medicine. "It wouldn't surprise me at all if it's a repetition of last year."Read more