The move comes as forward Carl Landry recovers from a left knee injury that occurred during the Hornets' loss at Detroit on Saturday night.
Landry posted on his Twitter account on Sunday that he has a sprained medial collateral ligament. The club has yet to announce how long Landry is expected to be out.
The 6-foot-8 Thomas, a second-year pro out of Duke, was in training camp with New Orleans and saw brief playing time in two of the Hornets' first three regular season games before being waived on Dec. 31.
Thomas spent his first pro season in the NBA Development League.