Defenseman Kris Letang has been placed on injured reserve.
Ruhwedel, 26, has helped WBS compile the top record in the AHL, tallying 13 points (3G-10A) in 26 games, the second-highest total among defensemen on the club.
Earlier this season, the 5-foot-11, 191-pound blueliner spent a couple days with Pittsburgh, but he did not appear in a game.
A native of San Diego, California, Ruhwedel broke into the NHL with the Buffalo Sabres as an undrafted free agent, collecting two assists in 33 NHL contests over parts of four years.
During his three-year college career at the University of Massachusetts-Lowell, Ruhwedel was an NCAA First-Team All-American his final year, helped his school reach the 2013 Frozen Four held at PPG Paints Arena and was teammates with Scott Wilson for two seasons.
