Hypoparathyroidism

A 64-year-old Caucasian female who is 4 weeks status post total parathyroidectomy with forearm gland insertion presents to the general surgeon for her post-operative checkup. She states that her mouth feels numb and she feels “tingly all over. The surgeon suspects the patient has hypoparathyroidism secondary to the parathyroidectomy with delayed vascularization of the implanted gland. She orders a Chem 20 to determine what electrolyte abnormalities may be present. The labs reveal a serum Ca++ of 7.1 mg/dl (normal 8.5 mg/dl-10.5 mg/dl) and phosphorous level of 5.6 mg/dl (normal 2.4-4.1 mg/dl). Question: What serious consequences of hypoparathyroidism occur and why?