I highly recommend knee and elbow pads if you don't already have them - I have old hard shell rollerblade ones that are sturdy enough to survive pavement. Full-fingered bike gloves are also good and, of course, a helmet. You can also get shorts with hip and butt padding for extra security.
Cement is challenging, partially because of the grooves between the sections but also because poles don't grip well on cement.
[missed as I was traveling to help a youngun move back to NYS;-]
Hmmm... I thought of padding for a bit, but didn't consider the helmet at all. I'll have to do that at least. (I certainly wore the helmet when rollerblading, not sure why I wouldn't think of it on the skis)