The media learned on November 8 that Shohei Tateyama had surgery on his right shoulder and elbow at a hospital in Gunma in early-October. He is already working out with the rehab group at the Toda facilities in Saitama and has resumed light throwing. There is no timetable on his full recovery. Tateyama will be in the final year of a three-year deal next season.
[UPDATE 11/27 @ 2:35pm]
Tateyama started playing catch earlier this month. He is now throwing at a distance of about forty meters. He could require three to four months for a full recovery.
Source: Sponichi 11/27/2017