From the Smoking Hot Needles website

This is a toe up sock pattern with a short row heel, called Jojo-heel or Boomerang-heel and it is very stretchy. I think it’s an ideal pattern for feet with swollen ankles, but you do not have to have them. They will fit various widths’ feet. You can play with yarn and needle sizes to get a larger or smaller sock. I’ve used three different yarns and three different needle sizes and was most pleased with the last one (Trekking XXL sock).