Paralysis is a disease in which the lower extremities of the body completely or partially lose motor function and the random movements are reduced or lost after the occurrence of random movement or loss of sensory disorders. Any lesion damage to the cortical motor projection area and upper motor neuron pathways can cause upper motor neuron paresis. Common causes include cranial trauma, tumors, inflammation, cerebrovascular disease, degeneration, poisoning, and certain diseases of internal medicine, such as diabetes, hematoporphyria, macrocytic anemia, and vitamin B12 deficiency. The following diseases are also causes of central paralysis of the lower limbs: 1. Amyotrophic lateral sclerosis Amyotrophic lateral sclerosis, also known as acromegaly, or ALS disease, is a type of motor neuron disease, which involves upper motor neurons (brain, brainstem, spinal cord) and affects lower motor neurons (cranial nerve nuclei, anterior horn cells of the spinal cord) and the muscles of the trunk, limbs, head and face innervated by a chronic It is a chronic progressive degenerative disease. Clinically, it is often manifested as a mixed paralysis with combined damage to upper and lower motor neurons. 2.Infant hydrocephalus Congenital hydrocephalus is a condition in which the intracranial cerebrospinal fluid is produced excessively or (and) the absorption reflux is impaired, then the ventricular system or (and) the subarachnoid space will accumulate a large amount of cerebrospinal fluid and expand, forming hydrocephalus. 3.Acute intracerebral hematoma Acute intracerebral hematoma is a hematoma in the brain parenchyma, which can occur in any part of the brain tissue, mostly in the frontal and temporal lobes, accounting for 80% of the total, followed by the parietal and occipital lobes accounting for about 10%, and the rest are located in the deep brain, basal ganglia, brainstem and cerebellum, respectively. Superficial intracerebral hematomas located in the frontal and anterior temporal portions and the base are often associated with cerebral contusions and subdural hematomas with acute clinical presentation. Deep hematomas, mostly in the white matter of the brain, are caused by the deformation of the brain by force or shear, resulting in deep vascular laceration and bleeding. When the hematoma is larger, the hematoma located near the basal ganglia, thalamus or ventricular wall may collapse into the ventricles and cause intraventricular hemorrhage, which is often serious and has a poor prognosis. 4.Green-Barre syndrome Green-Barre syndrome (GBS) is a common and serious disease of the nervous system. The main lesions are in the spinal nerve roots and spinal nerves, and may involve the cranial nerves. It is associated with viral infections or autoimmune reactions. The clinical presentation is acute, symmetric, flaccid limb paralysis.