Hard to tell in that pic, but I imagine it is carved not 'bent' just by looking at the grains. Could be mistaken though.
Usually bends are made by steam being applied to an area and slowly forming them with clamps or jigs.
IF I were to attempt it the wood making the knot would be a small branch and I would tie it up green and let it sit with teh rest of teh wood for a year or so then make the handle and shave the branch.