The radiating coldness in the left upper body may be caused by brain injury, spinal cord injury and sympathetic nerve injury. 1. Brain injury, typically caused by intracranial tumors, cerebral hemorrhage and other diseases, leads to damage to the sensory nerves on one side of the brain, which in turn causes radiating coldness and numbness on the left side of the upper half of the body. 2. Spinal cord injury, when the spinal cord is damaged due to inflammation, impact and other injuries, it will affect the sensory conduction process of the human body, which will also cause symptoms such as coldness in the upper left half of the body. 3. Sympathetic nerve injury, after suffering from this disease may appear Horner’s syndrome, its more typical symptoms are the upper half of the body cold, dull sensation and so on. Appear left upper body radiating cold need to timely brain, cervical spine MRI case and sympathetic nerve examination, to determine the specific cause of the disease, after a clear diagnosis and active treatment, so as not to delay the condition.