Pain at the bend of the leg may be caused by tendonitis, trauma, varicose veins of the lower limbs, osteoarthritis, rheumatoid arthritis and other diseases, patients should consult a doctor in time to clarify the cause of the disease and then treat it. 1. Tendonitis: aseptic inflammation of tendon and its surrounding tissues caused by excessive activities, preferably near the knee joint, patients will have local pain, pressure pain and leg bending pain, such people should pay attention to rest, local cold compresses, and ibuprofen and other medications can be used in case of severe pain. 2. Trauma: If the patient has a history of trauma before the occurrence of pain in the bend of the leg, it is possible that the knee ligament, meniscus and other tissue damage caused by the pain, such people should consult a doctor in a timely manner. 3. Varicose veins of the lower limbs: the backflow of blood in the veins caused by valve dysfunction of the superficial veins of the lower limbs, patients will have the onset of the side of the limbs of the bruises, leg pain, leg pain, discomfort and localized hyperpigmentation, this group of people can use compression stockings, and if necessary, surgical treatment. 4. Osteoarthritis: pain in the bend of the leg may also be caused by osteoarthritis, the patient will also have joint pressure and pain and limited mobility and bone friction, the acute attack should pay attention to rest, if necessary, the use of ibuprofen and other drugs for treatment. 5. Rheumatoid arthritis: patients with rheumatoid arthritis will also have pain in the bend of the leg, and such people will also have pain and swelling in the finger joints and rheumatoid nodules, which can be treated with ibuprofen, methotrexate and other drugs. All of the above medications and treatments should be administered under the supervision of a physician.