Katy Perry Brings Out the Worst in Runner’s Knee

Last night I was hanging with a Katy Perry impersonator. Cher and Elvis look-alikes were in our company, too, but Copycat Katy clearly rocked the holiday party this year, and my knee, with all her bouncing. Okay, it’s not entirely her fault. I bounced and danced and jumped and let the adrenaline of this great…