The Back To The Future star was diagnosed in 1991

During a Back to the Future Q&A at the Fan Expo in Philadelphia this past weekend, Michael J. Fox experienced a minor setback.
The 61-year-old retired man, who has fought heroically against Parkinson’s disease since 1991, made a little misstep as he made his way up the stage.
Fortunately, the couch on the stage was a cushion for the star’s fall, preventing a potentially more damaging impact on the floor.
The actor, unperturbed, recovered gracefully, joined the panel, and continued the program. Tom Wilson, 64, and Christopher Lloyd, 84, another Back to the Future co-star, were with him.