The symptoms of numbness in the thumb are commonly caused by the following: 1, due to acute injury and chronic strain, due to the presence of injury, there will be a corresponding local congestion, edema, inflammatory reaction, under the stimulation of inflammation and the role of local swelling and stretching, resulting in abnormal sensory nerves, will appear symptoms of numbness; 2, seen in lumbar disc herniation or lumbar spinal stenosis and other diseases, resulting in Nerve compression and stimulation in the lower extremity can also lead to abnormal sensation in the innervated area of the big toe, resulting in numbness; 3, seen in peripheral nerve injury or neuritis, such as local trauma leading to nerve rupture or nerve inflammation due to other diseases, such as diabetes often accompanied by neuritis, resulting in abnormal sensation in the big toe, resulting in numbness; 4, some cerebral infarction, cerebral ischemia or lacunar infarction, Cerebral ischemia or lacunar infarction can also lead to symptoms of numbness in the big toe, mainly due to ischemia and hypoxia in the sensory center, resulting in abnormal sensation.