Tetany (also known as tetanic seizure) is a term used to describe a condition whereby involuntary contraction of muscles (or muscle spasms) occurs in parts or systems of the human body as a result of hypocalcemia (low concentration of calcium in the blood); usually, low calcium levels lead to cramps, involuntary contraction of muscles in the arms, hands, legs and feet, and spasms in the larynx.
In medicine, hypocalcemia refers to a low level of calcium in the blood or a deficiency which is related to lack of vitamin D but also other conditions such as pancreatitis, kidney failures, etc. Besides this, serious deficiency of calcium can lead to confusion, heart attacks and tetany which refers to a type of seizure or involuntary muscule spams that are mostly related to hypocalcemia, although other factors such as excess of potassium or low levels of magnesium or carbon dioxide can also cause it. Therefore, the sustained muscle spasms from hypocalcemia are known as tetany.
Cerebrospinal Fluid (CSF) flows through the four ventricles and then flows between the meninges in an area called the subarachnoid space. CSF cushions the brain and spinal cord against forceful blows distributes important substances and carries away waste products.