Actor Shia LaBeouf’s recovery after undergoing “extensive” surgery on his left hand following the Sunday car crash in West Hollywood may be a lengthy process, his lawyer has revealed.

Michael Norris, Shia LaBeouf’s attorney, revealed in a statement Friday the real extent of injuries the 22-year-old actor suffered Sunday when his pickup truck rolled over as a result of collision with another vehicle.

Norris said LaBeouf underwent four hours of surgery and that his left arm remains immobilized from the elbow down.

Previous information was that LaBeouf needed a 30-day period to recover before returning on the set of “Transformers: Revenge of the Fallen.” Norris added Friday that the actor “will need regular medical supervision until his doctors clear him to return to work.”

While LaBeouf’s doctors “remain hopeful that he will fully recover,” Norris sounded less than optimistic when saying there is still “a substantial risk of both infection and other complications” due to the extensive surgery.

Michael Bay, director of 2006’s “Transformers,” which also starred Shia LaBeouf, and of the upcoming sequel told Access Hollywood in an interview which aired Friday that producers were thinking about including LaBeouf’s current condition into the script.

Bay also expressed his confidence that the young star was not drunk at the time of the accident and that this would soon clear up. He was arrested on suspicion of driving under the influence but authorities later determined the other driver had caused the accident, by running a red light.

The other driver and LaBeouf’s passenger, “Transformers” costar Isabel Lucas, suffered only minor injuries. Lucas returned on the set Monday.

The Associated Press reports the official investigation is under way and could take weeks to be completed. The other driver’s name will not be released before that.