Dennis Quaid -- Sued Over Near-Fatal Horse Accident

A horseback rider claims he was nearly killed while riding a horse on Dennis Quaid's equestrian estate, and he's suing the actor over his life-threatening injuries.

70-year-old Lester Wood claims Quaid gave him permission to use a trail on the actor's property to ride a horse to a nearby park in the exclusive Pacific Palisades area of L.A.

Wood said in an interview with the Palisadian-Post newspaper, the sprinkler system next to Quaid's trail suddenly activated, spooking the horse which reared up and fell on top of him.

Next thing Wood knew he was in critical condition at a nearby hospital with a concussion, fractured scapula, torn aorta, multiple pulmonary emboli, broken ribs, a nicked liver, a tear in his bladder, fractured lumbar discs, a shattered pelvis, internal bleeding, and a torn miniscus in his knee.

Wood says he was not wearing a helmet and was looking down at his watch at the time of the accident.

All told, Wood says the accident cost nearly $500,000 in medical bills -- and he blames Quaid -- who no longer owns the estate -- for what he believes is a flawed trail design.