A Study of Interparietal Bone in 105 Human Skulls of Gujarat Population.

Introduction : The squamous portion of the occipital bone consists of two different parts: the upper interparietal and the lower supraoccipital. The interparietal part may remain separated from the supraoccipital by a suture; it is then called the interparietal or Inca bone. Aim : In this study, incidence of interparietal bone has been estimated and compared with the other observations. Methodology : Total 105 cadaveric dry human skulls were examined to determine incidence of interparietal bone. Observations : The skulls which were observed, displayed many variations in the occipital region. In 7 cases, single or multiple separated bones were observed. In 4 cases (3.81%), the lower edge of these additional bones was situated above the external occipital protuberance and such bones could be classified as interparietal bones. In 3 cases (2.86%), the lower edge of these additional bones was much higher (between the lambda region and the highest nuchal line). The later can be classified as preinterparietal. Importance : Knowledge of interparietal bone is important for the radiologists, neurosurgeons, anthropologists, orthopedics and forensic experts to avoid misdiagnosis.

Study of interparietal bone.

It is not unusual to find small separate ossicles of bones between two lambdoid sutures and nuchal lines. Their size, shape, numbers and position are variable. These are interparietal bones. While routine examinations of bones, the authors have found an adult male skull having interparietal bone. The bone was examined thoroughly and conclusions drawn.