The coldness and numbness in the arms may be caused by poor blood circulation. 1, such as the presence of vasculitis in the upper limbs or diseases such as hypertension, diabetes, hyperlipidemia, etc., can lead to narrowing of the blood vessels, affecting the peripheral blood circulation, resulting in slow blood flow, which can lead to numbness and a feeling of coldness. This can be clarified through blood tests, blood glucose tests, blood pressure measurements and ultrasound examinations of the upper limbs. 2. Bad cervical spine can also lead to the above symptoms, if there is a herniated cervical disc or cervical osteophytes, etc., because of the compression of the nerve root on one side, thus causing numbness and coldness in the upper limbs, called neurogenic cervical spondylosis. 3. If cervical spondylosis is suspected, it can be clarified by doing a cervical spine magnetic resonance examination.