Brandon Roy has surgery on both knees

PORTLAND, Ore. -- Portland Trail Blazers guard Brandon Roy has undergone arthroscopic surgery on both of his knees.

There is no timetable for the three-time All-Star's return.

Roy has missed 18 games this season because of soreness in his knees, which he has said is caused by a lack of cartilage.

Roy is averaging 16.6 points in 23 games this season. For his career, the 2007 NBA Rookie of the Year is averaging 19.9 points and 4.9 assists.

Roy's surgery was performed Monday in Vancouver, Wash., by Dr. Don Roberts, a team physician.