Ankle has replaced your back as producing the most satisfying sensation when scratched, according to a new study

The researchers then used as laboratory brush to scratch the affected areas themselves in order to produce as consistent technique on all the areas and recorded the reaction of the volunteers who were asked how pleasurable the sensation was.
The researchers found that scratching the ankle produced the highest intensity and the longest period of satisfaction while scratching the forearm produced a briefer and lower intensity pleasure sensation.
Commenting on the findings, one of the researchers who took part in the study, Professor Francis McGlone said, “It was interesting that the ankle was the itchiest site and that the most pleasure came from scratching it, because the back has been well-known as a preferred site for scratching.”
Source-Medindia