Because people today wear socks or stockings, their toes do not all flatten out, so the force underfoot is not equal. Consequently, the force on the knees is also unequal, abnormal pressure is put on one side, there may be pain in the knee or fluid accumulation, and this is a cause of lower back pain.

The hallux valgus supporter Bochikun encloses the abductor hallucis muscle extending from the big toe and the abductor digiti minimi muscle extending from the little toe in the supporter itself, applies pressure from either side, stimulates both abductor muscles, and, in particular, makes it easier to return medially a big toe that has twisted laterally.