@BillW,
Wiki info excerpt on Yao:
"In July 2009, Yao discussed the (foot-toe) injury with his doctors, and the Rockets applied for a disabled player exception, an exception to the NBA Salary Cap which grants the injured player's team money to sign a free agent.[94] The Rockets were granted the exception, and used approximately $5.7 million on free agent Trevor Ariza. After weeks of consulting, it was decided that Yao would undergo surgery in order to repair the broken bone in his left foot.[95] He did not play the entire 2009–10 season.[96]
For the 2010–11 season, the Rockets will limit Yao to no more than 24 minutes a game, with no plan to play him on back-to-back nights. The goal is to keep Yao healthy long term."