ICD-9-CM 781.7 is a billable medical code that can be used to indicate a diagnosis on a reimbursement claim, however, 781.7 should only be used for claims with a date of service on or before September 30, 2015. For claims with a date of service on or after October 1, 2015, use an equivalent ICD-10-CM code (or codes).
A disorder characterized by muscle twitches, cramps, and carpopedal spasm, and when severe, laryngospasm and seizures. This condition is associated with unstable depolarization of axonal membranes, primarily in the peripheral nervous system. Tetany usually results from hypocalcemia or reduced serum levels of magnesium that may be associated with hyperventilation; hypoparathyroidism; rickets; uremia; or other conditions. (from Adams et al., Principles of Neurology, 6th ed, p1490)
Hyperexcitability of nerve and muscle when the concentration of extracellular ionized calcium is decreased