The 41-year-old is expected to be sidelined at least until the All-Star break.
Schilling has said he would have preferred surgery, but the team insisted that he first try rehab. The right-hander denied he was hurt when he signed a one-year, $8 million contract with the Red Sox in November.
Moving Schilling to the disabled list cleared space for Boston to sign right-hander Lincoln Holdzkom to the team's 40-man roster.
Holdzkom pitched for the Red Sox in the minors last season. He was selected by Philadelphia in the Rule 5 draft last December, but was placed on waivers this week.