Kidney opens at the two yīn

The kidney opens at the two yīn, i.e., the posterior yīn, which refers to the anus, and the anterior yīn, which refers to the genital organs. These organs are located in the lower burner, and their function is associated with kidney qì so that they are referred to as the outer orifices of the kidney. This relationship is also reflected in various diseases. For example, kidney vacuity may lead to changes in urination and defecation such as scant urine, long voidings of clear urine, incontinence and enduring diarrhea, or fecal incontinence. The reproductive system may also be affected, causing impotence, premature ejaculation, or seminal emission.