When it comes to rainy or cloudy days, some elderly people experience a dull ache in their knee joints. A sudden drop in temperature can leave finger joints swollen and sore. In more severe cases, people feel as if their spine is tied down, stiff and painful. Many arthritis patients even claim that their body’s reactions can predict weather changes more accurately than weather forecasts. Can joints really foresee the future and act as “weather forecasters”? As orthopedic and joint surgeons, we are here to uncover the scientific truth behind this phenomenon.
The Subtle Link Between Joints and Weather
Joints can respond to weather changes mainly because they are rich in sensory receptors. These receptors act like sensitive scouts, constantly monitoring the internal state of the joints and changes in the external environment. When the weather shifts—especially when there are significant fluctuations in air pressure, temperature, and humidity—the tissues around the joints undergo physical and chemical changes. These changes stimulate the receptors, which then transmit signals to the brain through nerves, leading to the sensation of joint discomfort.
A change in air pressure is one of the key factors affecting joints. When air pressure drops, the pressure difference between the inside and outside of the joint cavity increases, causing the synovial tissue of the joint to become edematous. The nerve endings in the joint are stimulated, triggering pain. For example, before a rainstorm, air pressure usually drops sharply, and many arthritis patients will notice a marked worsening of joint swelling and pain at this time.
The impact of sudden temperature drops on joints should not be underestimated. Cold temperatures cause blood vessels around the joints to constrict, slowing down blood circulation. Insufficient blood supply to the tissues surrounding the joints leads to the accumulation of metabolic waste, which irritates nerve endings and can induce pain. In addition, low temperatures reduce the elasticity and flexibility of muscles, ligaments, and other tissues around the joints, increasing the resistance to joint movement and further straining the joints, exacerbating pain.
Changes in humidity also affect joints. A high-humidity environment causes the tissues around the joints to absorb more moisture and become swollen, compressing nerve endings and resulting in pain. For people already suffering from rheumatoid arthritis, a high-humidity environment may trigger an inflammatory response, worsening joint pain and stiffness.
Patients with Specific Diseases Are More Sensitive
People with conditions such as osteoarthritis, rheumatoid arthritis, and gouty arthritis are more susceptible to the effects of weather changes on their joints.
Take osteoarthritis as an example. In such patients, the articular cartilage is already worn, bone spurs form around the joints, and the joint structure is damaged, making the nerve endings around the joints more easily stimulated. When the weather changes, alterations in joint pressure, temperature, and humidity directly irritate these damaged areas, leading to intensified pain.
Rheumatoid arthritis is an autoimmune disease in which the synovial membrane of the joints undergoes an inflammatory response, producing a large number of inflammatory mediators. When the weather changes, the body’s immune system is affected, and the secretion of inflammatory mediators increases, further aggravating joint inflammation and making symptoms such as joint pain, swelling, and stiffness more pronounced.
Gouty arthritis is caused by abnormal uric acid metabolism in the body, with urate crystals depositing in the joints. Weather changes may affect the solubility of urate, causing crystals to precipitate or dissolve, thereby stimulating the joints and triggering pain.
