Located behind the thyroid gland are four tiny parathyroid glands. These make hormones that help control calcium and phosphorous levels in the body. The parathyroid glands are necessary for proper bone development. In response to too little calcium in the diet, the parathyroid glands make parathyroid hormone, or PTH, that takes calcium from bones so that it will be available in the blood for nerve conduction and muscle contraction.
If the parathyroids are removed during a thyroid operation, low blood calcium will result in symptoms such as irregular heartbeat, muscle spasms, tingling in the hands and feet, and possibly difficulty breathing. A tumor or chronic illness can cause too much secretion of PTH and lead to bone pain, kidney stones, increased urination, muscle weakness, and fatigue.
Parathyroid surgery is done to treat parathyroid problems such as hyperparathyroidism, enlarged parathyroid glands (parathyroid hyperplasia), and benign tumor (adenoma).
If all the four parathyroid gland are enlarged, your surgeon removes the major part of parathyroid gland leaving behind a part of the gland in place
If one of the parathyroid gland is affected by adenoma, your surgeon will only remove the affected gland leaving behind the remaining unaffected glands
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