A leg without strength is common in the following aspects: 1, the important thing is acute cerebrovascular lesions, such as cerebral infarction, cerebral hemorrhage can lead to a leg without strength, but in order to diagnose cerebrovascular disease, need to combine the onset of the patient’s onset, time of onset and onset of the situation, there is no accompanied by dizziness, headache, blurred vision, speech and other symptoms to determine, and need to improve the cranial CT, cranial magnetic resonance to further clarify the diagnosis. If acute cerebrovascular lesions are excluded, we should see if there is lumbar spine lesion, if lumbar spine lesion compresses the nerves, it can lead to pain, numbness, and weakness of one leg.3 Lower limb vascular lesions lead to ischemia of the lower limbs, which leads to weakness of the legs.4 Peripheral neuropathy can lead to weakness of one leg. If you have no strength in one leg, it is recommended that you go to a regular hospital to get a clear diagnosis.