Help swollen leg and foot

[caljw]

Here is a picture of my 2 month old Morans. She is very swollen from her leg joint and through her foot. No sign of blistering it almost looks like something may be wrapped around her leg restricting circulation but I can't determine that for sure??? Any ideas?
She doesn't seem to be distressed, obvious trouble walking but everything else about her is normal. Thanks for your help.