Is it acne or backne?

One of the strange things most of my children have gone through is not related to acne on their faces, but they've had to seek acne treatment for an acne like breakout on their backs. It probably has a more precise name, but we call it "backne" and it can get severe enough that if not treated properly can create scaring. Which if you are a teenage girl and it's summer time, can be a problem. It seems that stronger strength acne medication works better, that one that would create too much drying on their faces worked faster on the back area.