Before any back problems can be addressed with respect to Rob Gronkowski, doctors must first take care of priority No. 1.

The Patriots tight end will have a fourth procedure performed on his left forearm tomorrow at Massachusetts General Hospital, according to a source with knowledge of the situation.

The date was somewhat up in the air, but come tomorrow Gronk will have some definitive answers about whether he’s finally free and clear from an infection that’s dogged him for months.

It’s been widely reported that Dr. Jesse Jupiter will perform the surgery. According to MGH’s website, Jupiter specializes in the care of traumatic and reconstructive problems of the upper limbs, including fracture healing and failure to heal. Dr. Thomas Gill, the Patriots head team physician, is also expected to be on hand.

Cultures are expected to be taken from the forearm, and if they come back clean of infection, a new plate will replace the one that’s been keeping the broken forearm bone in place. If the cultures still have evidence of infection, Jupiter won’t be able to put in the new plate, and it’s back to square one, and the possibility of missed games creeps into the equation.

Results from the cultures are expected to come one week after surgery. If all goes well, the plate will be switched, and Gronk will start out on his 10-11 week recovery phase.