After having his right knee replaced at Rush University Medical Center, Bush was back in the Windy City Saturday to have his left knee partially replaced.
"He's looking forward to getting back on his mountain bike in a few weeks," Bush spokesman Freddy Ford told reporters.
The surgery was an outpatient procedure, and Bush and former first lady Laura flew back to their home in Dallas on Monday.
Bush has long had trouble with his knees, tearing a meniscus in 2004 that forced him to trade jogging for mountain biking and visibly limping in recent interviews.
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