It remains unclear as to how the injury happened but his reps confirmed to Deadline that he sought medical attention in Sofia.
It has been reported that doctors wanted to operate on the star immediately but he insisted on flying back to the US to undergo treatment.
Nicolas, 53, is said to have already flown back to California meaning the film will have to continue filming by working around his absence or halt production.
Millenium Films and Nu Image have not yet confirmed how his absence will affect the progress of the movie but Deadline reports that the set has been shut down as they await his return.
The film, #211, tells the story of a bank robbery that a police officer attempts to stop and is named after the code used to describe a heist in progress.
His son Weston, who he shares with Christina Fulton, will also star in the action-packed offering.
t comes after the 26-year-old was arrested on suspicion of driving under the influence after reportedly crashing his car in February.
According to TMZ, he lost control of his vehicle before crashing into some mailboxes after attempting to flee an incident in California.
His car reportedly came to a halt with the help of a tree, losing a tyre.(Express.co.uk)