A 20-year-old Iranian male after injury in a football match with pain in the fnger was referred to the hospital. X-Ray images of his hand showed no fractures, but the shortening of third to ffth metacarpal bones was clearly observed. The short metacarpal bone is a very helpful diagnostic marker in the patients suffering from idiopathic hypoparathyroidism (IHP), pseudohypoparathyroidism type Ia (PHP-Ia) with Albright"s hereditary osteodystrophy (AHO) phenotype, pseudopseudohypoparathyroidism (PPHP), and brachydactyly type E. Briefly, in hypoparathyroidism disease, the serum calcium level decreases and the serum phosphorus level increases in blood. PHP-Ia disorder is clinically similar to hypoparathyroidism; in this disease, the level of parathyroid hormone is normal but there is resistance to it. PPHP disease is not an endocrine disorder but is related to PHP-Ia. In this disease, serum levels of calcium and phosphorus are normal, also symptoms and signs in PPHP are similar to PHP-Ia, but there is no resistance to parathyroid hormone. In brachydactyly type E, shortening of metacarpal or metatarsal bones is caused by abnormal development of phalanxes, metacarpals, or both. His laboratory tests revealed a low serum calcium level, high serum phosphate level, and low serum PTH level; therefore a diagnosis of IHP was reached.