I was walking down the hallway recently with a young lady who appeared to be about 26 or 27. She was kindly helping me to find my way to an appointment with a specialist. As we walked along, she apologized for her gait, explaining that she had recently experienced knee surgery. She played sports in high school and college and her knees were now bothering her as she aged. Aged? Are you kidding? She had not hit 30 yet.