The main reasons for the coolness of the finger joints in the hands are related to joint inflammation, prolonged exposure to cold, and neurological disorders. 1. Joint inflammation: If there is inflammation in the finger joints of the hands, such as osteoarthritis, traumatic arthritis, etc., the stimulation of inflammation can lead to coldness as well as pain and swelling in the finger joints of the hands. 2. Prolonged exposure to cold: If the fingers are in a cold environment for a long time, such as not paying attention to keep warm in the winter cold season, it is easy to produce the symptoms of cold finger joints. If only the middle finger joints are cold, the joints may have been traumatized in the past. 3. Neurological lesions: If the peripheral nerves of the upper limbs are damaged or there is nerve root cervical spondylosis, it is easy to affect the sensory function of the fingers, which will produce the symptom of cold finger joints. If the symptoms of cold knuckles in the hands are more serious and last for a long time, it is recommended to consult a doctor in time to clarify the cause of the disease and target treatment under the guidance of a professional physician to avoid affecting daily life.