Auntie Li came from her cool southwestern hometown to hot Guangzhou to help take care of her daughter who had just given birth. But when she woke up the next morning, she found that she had become a patient! Auntie Li’s left foot and ankle were red, swollen and hot, and she could not walk on the ground at all; was it an acute attack of gout? Auntie Li told me that she did not eat seafood and animal offal food, and her blood uric acid was usually well controlled; only last night she felt the heat was unbearable and blew the air conditioner overnight, so her left foot was directly against the air conditioner. The result of the examination also found that the blood uric acid was not high. Is it true that the air conditioning is causing the inflammation in the foot and ankle? Weather change and pain Certain people who have a history of trauma or surgery often experience vague discomfort in the injured area before the weather changes and accurately ‘forecasts the weather’. It has been observed that when there is a change in temperature greater than 30C or a change in humidity of more than 10%, there is a significant increase in the number of patients seeking medical attention for joint pain. Changes in weather actually have some mysterious and close connection with human diseases! However, this connection has not been uncovered by modern medicine until now. Why are there more patients with joint pain in rainy and humid weather? Why does blowing on air conditioners induce rheumatoid arthritis or other joint pathologies? Some think it may be related to the geomagnetic field, the oxygen level in the air or the biological clock of hormone secretion. More people believe that it may be due to both weather changes and the patient’s own physical condition and underlying disease. When peripheral cold sensory receptors sense a more drastic drop in skin temperature, through peripheral nerve conduction to the center, central regulation will reflexively make local vasoconstriction, blood flow rate decreases; further when there is local tissue underlying disease or external compression, in the inflammatory site or compression to distant parts especially the foot or ankle joint is more likely to increase exudation and acute inflammatory response. This is how Auntie Li’s foot and ankle arthritis arose. This condition, according to Chinese medicine, is caused by wind and cold entering the lobe. In the hot summer, the possibility of wind chill in the human body is smaller than in spring and autumn, but it is not uncommon for the excessive application of air conditioners and fans to lead to localized wind chill such as in the ankle and foot joints. Who should be careful blowing air conditioning? People with a history of chronic diseases such as gout, diabetes, rheumatoid, and the sequelae of chronic trauma to the foot and ankle should be careful when blowing air conditioners! Patients with a history of chronic diseases such as gout, rheumatoid, etc., because of chronic ankle arthritis, metatarsophalangeal arthritis or ankle-foot synovitis often exist in the foot and ankle, in the air conditioning environment, if the local cooling of the ankle and foot is rapid and intense (such as a long time to blow the foot and ankle or joint parts against the air conditioner or fan), and the surrounding tissues due to the heat of the day and pore expansion, may lead to vascular nerve dysfunction, local temperature drop, blood flow rate Slow down, metabolic products gather in the local area, thus inducing an acute attack of inflammation. For example, Auntie Li was diagnosed with ‘gout’ due to high blood uric acid in the past and has a history of gout; although the blood uric acid is not high in this examination, localized elevation of uric acid in the ankle and foot can lead to an acute attack of localized gout. Similarly, patients with a history of diabetes mellitus have narrowed blood vessel walls in the ankle and foot due to thickening and reduced blood flow rate; more importantly, chronic diabetic patients often have peripheral neuropathy and nerve sensory impairment, and are unable to feel the peripheral injurious stimulation, which induces redness and pain in the foot and ankle after local cooling. And those who have had serious sprains or post-traumatic injuries to the foot and ankle should likewise pay attention! The nerve endings in the injured area may also sense abnormalities during rapid changes in heat or cold and induce acute inflammatory episodes. How to avoid it? Strengthening exercise, enhancing physical fitness and avoiding prolonged direct contact with air-conditioned air may be powerful measures to reduce acute inflammatory attacks in the foot and ankle. For patients with a previous history of chronic foot and ankle disease, local warmth (such as wearing ankle guards or outsourcing towel quilts) to prevent moisture is a necessary safety precaution for leaving the air conditioner on overnight. For those fans who drink beer and watch football late into the night, it is even more important to protect their feet and ankles. In the event of an acute inflammatory attack in the foot and ankle, do not rush and go to a nearby hospital immediately. Application of aspirin or NSAID drugs under doctor’s guidance, or application of drugs to lower blood sugar and control blood uric acid for the cause, or local injection of hormones into the joint may quickly resolve the pain and restore the function of the joint. The foot and ankle are located at the very end of the body, and they are most vulnerable to minor strain and injury as they bear the weight of the body during the day and are in contact with the earth.