Kearns will have an arthroscopic procedure to remove bone fragments in his throwing elbow. He was placed on the 15-day disabled list Thursday. The Nationals will make a corresponding roster move prior to Friday's series opener against the Milwaukee Brewers.
Kearns has struggled all season, batting .187 with three home runs and 16 RBIs.
The Nationals now have seven players on the disabled list, including four members of the opening night starting lineup: Kearns, first baseman Nick Johnson, catcher Paul Lo Duca and second baseman Ronnie Belliard. Closer Chad Cordero is also on the DL.