What was Craig rubbing on his scar?

When I had my knee replacement they did a skin graft also some the nerves behind my knee were removed and put on the front which makes it feel like you're touching the back part of my leg rather than the front, it's kinda weird, anyways the doctors told me to rub it like he was on the show to eventually make it feel normal again. His injury looked pretty serious so probably had more than just a knee surgery and I had a few other things done too(on my leg including knee rebuilt/replaced . Most likely he wasn't rubbing anything on it just his hand... could be wrong but with a major surgery and from what I'd think.