Hypoparathyroidism is most often the result of surgical miscutting of the parathyroid glands or injury to their supplying vessels (e.g., thyroid surgery), and in idiopathic cases the cause is unknown. Clinically, the main manifestations are tingling in the extremities, intermittent convulsions, spasmodic twitching of the extremities and emotional instability. Skin roughness, hair thinning, enamel defects, corneal ulcers and cataracts are also seen. Laboratory tests suggest decreased urinary calcium and phosphorus, increased blood phosphorus, decreased blood calcium, and normal or decreased blood alkaline phosphatase. X-ray examination: the whole body bone quality is mostly normal. A few of them show extensive or limited osteosclerosis, including thickening of the inner and outer plates of the skull, sclerosis of the acetabulum, femoral head and subsacroiliac joint surfaces, banded hyperdensity of the long bone epiphysis, and hyperdensity of the end phalanges. Calcification of intracranial structures, vertebral ligaments and periarticular tissues. In congenital cases, premature healing of the epiphysis and short fingers (toes) may occur. CT examination: intracranial basal ganglia, cerebellar dentate nucleus and cerebral hemispheres with multiple calcifications, which often appear as irregular plaques of high density shadow with symmetrical distribution. Treatment principle: At present, vitamin D and calcium supplementation are mainly taken to make serum calcium basically close to normal and serum phosphorus decrease to prevent hand-foot twitching attacks and ectopic calcification.