The 6-foot-11 Drummond is averaging 7.3 points and 7.5 rebounds per game. He was selected to participate in the Rising Stars Challenge as part of All-Star Weekend later this month, but now his promising season is on hold.
"He should get better. He'll heal. He should have no residual," team physician Ben Paolucci said. "He's not going to have anything lasting."
The Pistons discovered the fracture of the fifth lumbar vertebra after Drummond was examined Thursday. He played only 8 minutes against New York on Monday and 5 against Brooklyn two nights later.
Drummond does not need surgery, and team doctors anticipate a full recovery with rest and rehabilitation.
Drummond was taken with the ninth pick in last year's NBA draft out of Connecticut. He has eight double-doubles and 84 blocked shots.
Duncan was out on the court shooting about two hours before Friday's game, but he's been bothered by a sore left knee. Ginobili has left hamstring tightness.