Eric Dane opened up about his recent ALS diagnosis on "Good Morning America," telling Diane Sawyer that he now only has "one functioning arm."

Eric Dane reflects on his ALS diagnosis and the close relationship with Rebecca Gayheart after their reconciliation earlier this year

Eric Dane is sharing the first heartbreaking details about the challenges stemming from his ALS battle. The "Grey's Anatomy" star, 52, sat down for his first TV interview since going public with the illness,