Why does tendon sheath inflammation hurt more at night?

Tenosynovitis often causes severe pain at night, which is related to factors such as excessive fatigue during the day, localized cold exposure, and prolonged inactivity of the hands. 1. Excessive fatigue during the day: Patients with tenosynovitis who engage in excessive hand activity and overexertion during the day may experience repeated mechanical friction of the tendon sheath. 2. During nighttime rest, noticeable edema may develop in the tendon sheath area, intensifying the pain. 3. Localized cold exposure: Failure to keep the hands warm at night, or prolonged exposure to air conditioning or fans, may cause cold exposure to the affected area, resulting in insufficient blood supply and further exacerbating the pain. 4. Prolonged inactivity of the hands: During nighttime sleep, prolonged inactivity of the hands may lead to fluid leakage from capillaries into the affected joints, causing congestion, edema, or exudation of tissues, which can worsen pain in the tendon sheath area. Patients should ensure adequate rest, avoid excessive strain, keep the affected area warm, and follow medical advice for active treatment.