It will depend on the technical part of the procedure. Which screw had been removed and whether that screw was a primary fixation method or a reinforcement screw will dictate the end result. If there is still adequate fixation of the graft, then it might go on to heal. It will again depend on the type of graft since bone-tendon-bone graft can start healing as soon as 6 weeks while hamstring graft takes a longer time to incorporate. The best thing to do is to protect the knee from any additional injury, trauma or force (taking for granted that the knee is stable after removing the screw) for upto 6 months. If the knee is unstable or graft is non-functional, then another surgery may be needed. The best decision would be made by the surgeon who did the surgery.