The procedure will fix a torn ulnar collateral ligament in his left thumb. Because he played through the injury, his surgery may be a little more complicated than it would be typically. Rather than re-attach good ends of the ligament, doctors might otherwise choose to take a wrist tendon to use in the thumb.
The latter option is not uncommon, but it is a bit more complex. Pedroia described the procedure as "like Tommy John surgery" but to his thumb. Tommy John is often performed on torn UCLs in the elbow.
Pedroia originally injured his thumb in the first game of the season sliding head-first into first base. Despite the pain, he still managed to pick up the most plate appearances in the league while hitting .301/.372/.415. He hit just nine home runs, the first time since 2007 he has failed to reach double-digits.
Depending on which kind of surgery is chosen, Pedroia will need 4-6 or 6-8 weeks of recovery time. He is still expected to be fully healthy by the time spring training rolls around.