Roger Federer has retired, mostly due to his knee. This is tragic but extremely common and often avoidable. Here is how.
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Meniscus Repair
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Impact of Roger Federer missing 2016 season, Olympics - Sports
Roger Federer - Wikipedia
Why Surgeons Don't Repair Many Meniscus Tears
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Pushing 39, taking a year off - is the end of Roger Federer's
