The child’s legs to tense up the suggestion to go to the hospital to identify the cause of the symptomatic treatment, generally appear this phenomenon is caused by high muscle tone, brain injury, calcium deficiency. 1. High muscle tone: you can apply local hot massage to improve microcirculation. Supplementation of some nutritive nerve medication is conducive to the recovery of the body. Then active rehabilitation training, you can go to a professional children’s rehabilitation hospital or outpatient systematic treatment. 2. Brain injury: adopt neuroprotective treatment. According to the severity and cause of brain injury, appropriate application of neurotrophic drugs or other physical therapy, such as subcooling therapy, neurotrophic factor, hyperbaric oxygen therapy, etc., to maintain the stability of the internal environment and reduce intracranial hypertension. 3. Calcium deficiency: calcium carbonate, calcium lactate can be taken, in addition, the patient can also be intravenous calcium gluconate. Secondly, it is also necessary to supplement vitamin D, because vitamin D can promote calcium absorption, so it is necessary to supplement vitamin D in calcium deficiency. The child’s legs are straining hard, it is recommended to go to the hospital in time, to clarify the cause and timely intervention.