A dragging gait of the lower extremities is a clinical manifestation of corticospinal tract lesions in gait abnormalities. In corticospinal tract lesions, spastic hemiplegic gait is a unilateral lesion. The upper extremity is usually in a flexed, pronated position, with the lumbar region tilted to the healthy side, while the lower extremity is straightened and externally rotated, with outward forward swaying to compensate for the weakness of the hip, knee flexors and ankle dorsiflexors. What can cause lower limb dragging gait? 1, seen in cerebrovascular disease encephalitis traumatic brain injury and other sequelae. In 30% to 50% of cases, the cause cannot be found and it is idiopathic pediatric acute hemiplegia. The remaining cases can find the primary disease and are called symptomatic (secondary) pediatric acute hemiplegia. Secondary pediatric acute hemiparesis is commonly associated with infections, immune diseases, intracranial vascular malformations, craniocerebral trauma, cardiac diseases, hematologic diseases, and metabolic diseases. All these diseases can cause occlusive lesions of cerebral blood vessels, thus causing hemiplegia. 2.Spastic paraplegic gait is seen in spastic paraplegic cerebral palsy, transverse spinal cord damage cerebral palsy, hereditary spastic palsy, lateral sclerosis, corticospinal tract degeneration and other diseases. (1) Type I: Type I patients develop before the age of 35. Most patients with simplex HSP type I are male, and the age of onset of AR-HSP is often between 3 and 6 years or within 10 years. (2) Type II: Simplex HSP type II patients develop after the age of 35. AD-HSP develops later, with a mean age of 18 years, with obvious cone bundle signs, often with sensory disturbances and sphincter disorders.