There are two main reasons for hamstring pain in the foot joint: 1, trauma, such as ankle sprains, sprains lead to ligament edema and bruising and swelling, the peripheral nerves around the stimulation and pain sensation. Or due to the first injury did not carry out adequate plaster or support external fixation, resulting in the ankle joint did not fully recover, the formation of habitual ankle sprain. When walking on uneven surfaces, as well as when performing little activity, the ankle joint may be induced to sprain again. Because the previously damaged ligaments have not fully recovered, the formation of aseptic inflammatory lesions, ligaments become more fragile, decreased elasticity, decreased toughness. 2, the ankle joint due to too much activity strain, and accompanied by cold conditions. Because strain injury will form aseptic inflammatory lesions in the local area, once cold will lead to slow blood circulation, local venous return decreased, resulting in inflammation accumulation, easily lead to ankle joint pain.