I was wondering the same thing - came online to find out, no luck. But my fiance did hear on TV that it's a shoulder brace, because she's had like 3 shoulder surgeries is what I read online.
Honestly my first thought was that she had some tattoo that had to be covered because she's in China, but that's not the case! It's some fancy shoulder brace - modern medicine, go figure.
TV and on-line references to Kerri's 3 shoulder surgeries