Yes, in certain cases calcium ion concentration in the blood leads to tetany. Calcium plays a significant role in muscle contraction.

• The parathyroid glands secretes parathyroid hormones, which increases the concentration of Ca2+ ions in the bloodstream.

• During the deficiency of the parathyroid hormone, the Ca2+ concentration would decline. The decrease in the Ca2+ levels would result in excitability in the muscles and nerves, which results in cramps and convulsions in the muscles.

Therefore, Calcium ion concentration in the blood affects muscle contraction. When these contractions are sustained due to low levels of parathyroid hormone, which causes a decrease in the Ca2+ concentration and affects the muscles of larynx, hands, feet, and face, this is known as parathyroid tetany. Thus, fluctuation in blood calcium concentration can lead to tetany.