The numbness of the four fingers of the left hand may be related to cervical spondylosis, peripheral neuritis, diabetes and other reasons. 1. Cervical spondylosis: when the cervical spine has degenerative lesions triggered by joint dislocation, it will affect the surrounding soft tissues, so that the blood vessels and nerves in the neck are stimulated, and the phenomenon of numbness in the four fingers of the left hand will occur. 2. Peripheral neuritis: Inflammation due to poisoning, infection, finger blood supply disorders and other reasons, resulting in numbness of the four fingers of the left hand. 3. Diabetes: patients with high blood sugar, peripheral nerve damage and other complications, resulting in numbness of the four fingers of the left hand. The cause of numbness of the four fingers of the left hand may also be related to carpal tunnel syndrome, cerebrovascular disease and other causes, it is recommended that patients should go to the hospital in a timely manner, under the guidance of the doctor for treatment.