Calf swelling and sinking may be caused by standing for too long, varicose veins of the lower limbs, osteoarthritis of the knee, etc. Generally speaking, conservative treatment, medication and surgical treatment can be taken. 1. Standing for a long time: standing for a long time usually leads to overloading of calf muscles, poor blood circulation in the lower limbs, and swelling and sinking of calves, etc. Generally, conservative treatment can be taken to avoid standing for a long time, take proper rest, and elevate the lower limbs to promote blood return. 2. Varicose veins of the lower limbs: Varicose veins of the lower limbs may be caused by venous valve closure insufficiency and persistent elevation of pressure in the veins, which may cause symptoms such as swelling and sinking of the calves, and can be treated with venous active medicines such as Diosmin and Bicoumarin under the guidance of a doctor. Surgical treatments such as vein valve transplantation and vein valve repair are also available. 3. Osteoarthritis of the knee: It is a chronic joint disease caused by joint degeneration and damage to the articular cartilage, which usually causes pain and stiffness in the knee joint, and also swelling and sinking of the calf. Medications such as bisacodyl and glucosamine can be used under a doctor’s supervision. Minimally invasive surgical arthroscopic cleanup and artificial joint replacement can also be used for treatment. Diseases that cause swelling and sinking of the calves also include lumbar spinal stenosis, lumbar vertebral body slippage and arteritis of the lower limbs, etc. It is recommended that the patient consult a doctor as soon as possible, cooperate with the doctor to find out the cause of the disease, and carry out treatment.