Rat is too wiggly-- how do I look at wound?

I'm trying to get a better look at an injury Grizz has but I can't get her to sit still long enough to get a good look. It's in a tough place, right in her armpit, and I can't hold her and part the fur at the same time with her wiggling like a maniac. How can I get a better look/make her sit still? Is it possible? I think she may have an abscess from being bitten but I can't tell.