The top three, in addition to Medvedev, includes the German Alexander Zverev and the Spaniard Rafael Nadal.
Serb Novak Djokovic is in seventh place.
Andrei Rublev is in eighth position.
Karen Khachanov moved up from 26th to 23rd place, while Aslan Karatsev remained at 37th.
Earlier, Zverev told with whom he is discussing his return after the operation.