The main clinical manifestations of postpartum lumbar and leg pain, mostly to the waist, buttocks and lumbosacral pain day and night mainly, can be accompanied by one side or both sides of the leg pain, the pain site is mostly in the lower limbs of the medial or lateral, can be accompanied by the lower limbs of the heaviness, aching and soft and other symptoms. It is a relatively common phenomenon among women who have given birth, and the incidence rate is as high as 70%. Common causes: 1, hormone level changes during pregnancy, generalized edema caused by the sacroiliac tendon ligaments become lax, strength deterioration; 2, post-partum rest is not appropriate, premature and long-lasting standing and sitting, resulting in maternal pregnancy lax sacroiliac ligaments can not be restored, resulting in strain injury; 3, the maternal delivery process caused by the pelvic ligament injuries, coupled with post-partum premature labor and weight-bearing, increased sacroiliac joint injury opportunities, resulting in the joint capsule around the tissue damage. Injuries caused by various ligaments in the pelvis during childbirth, coupled with early labor and weight bearing after delivery, increase the chances of injury to the sacroiliac joints, causing adhesions around the joint capsule and impeding the normal movement of the sacroiliac joints; 4. Postpartum carelessness in getting up and living in a house, flash frustration of the lumbar kidneys and lumbosacral congenital disorders, such as cryptic arch bifida, sacral bifida, and lumbar spine sacralization, etc., which induce lumbar pain, and it is more acute after delivery; 5. Physiological calcium deficiency and postnatal exposure to cold, etc., which can induce it.