The Minnesota Timberwolves announced today that center Theo Ratliff will undergo exploratory arthroscopic surgery on his right knee on Tuesday, Dec. 18. Dr. James R. Andrews of the Alabama Sports Medicine & Orthopaedic Center in Birmingham, Ala., will perform the operation. Due to the exploratory nature of the procedure, a timetable for his return will be established following the operation.

Ratliff, acquired via trade from the Boston Celtics on July 31, 2007, has appeared in six games for the Wolves this season, averaging 8.2 points, 4.5 rebounds and 2.8 blocks in 26.8 minutes per game. The 12-year NBA veteran has missed the last 13 games due to soreness in his right knee.