Michael Douglas’ son Cameron, can’t stay clean. He got busted this month for having drugs in his system at the federal prison in Loretto, Pa., where he’s serving a 10-year stint for dealing, The Post reports.

Douglas failed a urinalysis and was immediately sent to solitary confinement the first week of January, according to a prison source.

No word on whether he’ll face additional jail time for the infraction or how long he’ll stew in the hole.

Recently, Douglas suffered a broken leg and finger behind bars after a crime-family captain put a $100 bounty on him for being a “rat,” a prison insider says.

The source says that Douglas mysteriously suffered the injuries after a New York City mobster offered payment to anyone who hurt the drug-dealing scion during flag-football season this fall at Loretto, Pa.

“He broke his femur, which is hard to snap, and had to have a rod inserted,” says the source. “He told health services staff that he hurt them playing handball. You don’t break a femur playing handball.”

Douglas, who is doing a nearly 10-year stretch for dealing crystal meth and smuggling in drugs for himself while in the pokey, was inadvertently exposed as a turncoat by his shrink during a bail hearing in 2010.

The insider says that the pampered, baby-faced Douglas has “gone gangster” in the joint, reshaping himself by pumping iron and getting prison tattoos.

Cameron, who turned rat and got five years instead of 10 in 2009 — only to get an extra 4 1/2 years for smuggling in heroin and a prescription narcotic while at the Metropolitan Correctional Center — has been working as a weekend orderly in a housing unit and earning $1.65 per month.

He is not eligible to be released until 2018.

Go to The Post for the full report.