Numbness of the left arm and shaking hands may be related to multiple etiologies such as neck disorders and cerebrovascular diseases. 1. Neck disease. When cervical spondylosis leads to disc herniation or intervertebral stenosis, resulting in nerve compression, numbness of the fingers may also occur. Especially in spinal cord cervical spondylosis, the symptoms of paroxysmal pain or numbness in the limbs will often occur, and in severe cases, the symptoms of shaking will also occur. 2. Cerebrovascular disease. Left hand finger numbness, shaking also need to exclude the possibility of cerebrovascular disease, common such as cerebral blood supply insufficiency or cerebral infarction, etc., may appear finger numbness, hand shaking and other symptoms. Causes of left hand numbness, shaking of the cause is more complex, the occurrence of the above symptoms, need to consult a doctor in a timely manner to clarify the specific causes of the disease.