Anatomical Variations Of Inca Bone In Adult Human Egyptian Skulls

Background: The Inca bone is integral part of the occipital bone of the skull in its interparietal region andappears during radiological examination of the skull.Aim of the work: This study aimed to estimate the incidence rates and variations of interparietal (Inca) andpreinterparietal bones in adult human Egyptian skulls .Materials and methods: In the present study 60 dry human Egyptian skulls (37 males and 23 females) wereexamined to determine the incidence rates of Inca and preinterparietal bones with detailed measurements forInca bone in mm using electronic digital caliber.Results: The incidence rates of Inca and preinterparietal bones were higher in male skulls than female skulls andthe interparietal or Inca bone was observed in only 4 skulls ( 6.66% ) while the preinterparietal bone wasobserved only in 2 skulls ( 3.33 %) .Conclusion: The presence of the Inca and preinterparietal bones was rare in the human Egyptian skulls andtheir incidence rates were higher in male skulls .

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.