Mine would hurt, no matter what direction the pressure went, if it changed quickly. The pain would last only about 10-15 minutes, then settle back down. Even this summer when we had the remnants of a hurricane come through, I had bad pains in my new knee. But the barometric dropped very low very quickly. It wasn't only my new knee that hurt. So did my old knee and my repaired shoulder and healed broken foot and ankle! I guess I'm just a weather predictor!