A STUDY OF THE PTERION IN THE CHINESE CRANIA / 解剖学报

ABSTRACT

The pterion of 739 crania of the Chinese (adult male 486 cases, adult female 181 cases and young specimen of both sexes 72 cases) was studied. The pterion in the form of spheno-parietal suture was highest in percentage (77.94?1.08％). The percentage of the form of epipteric bone (19.22?1.02％) was higher than that of the temporofrontal suture (2.03?0.36％). The K-form represented only in 0.81?0.23％. In the form of spheno-parietal suture, the percentage of the wide H-type was highest (57.98?1.28％). The form of epipteric bone was found to be more common in nonadults than in adults. The N-type occurred more frequently in the male adults than in the female adults. Region and side failed to show any statistical importance in the percentage distribution of other forms. The group with epipteric bones was divided into three main classes, namely, with a single os epiptericum, with double, or multiple ossa epipterica. The percentage of those with a single os epiptericum was much higher (82.04?2.28％) than that of the other two classes (15.14?2.12％ and 2.82?0.92％). In the forms of the single os epiptericum, os epiptericum posterius was found in 6.77?0.66％, os epiptericum typicum in 6.50?0.64％, and os epiptericum anterius in 2.30?0.39％. In the forms of the double ossa epipterica, the united type occurred in 2.50?0.41％ and the separated type in 0.41?0.16％. In the forms of the multiple ossa epipterica only the united type was found in 0.54?0.18％. The centre of pterion was situated at 30.1 mm behind and 11.7 mm above the fronto-zygomatic suture or 37.7 mm above the baseline. In the pterion region the presence of the canal for the anterior branch of the middle meningeal artery was 60.83?2.75％. The bony canal that lay opposite the centre of pterion occurred more frequently in percentage 44.27?2.80％ and that lied below and behind the centre of pterion was relatively small in number (6.69％ and 6.37％), however, that lay in front of the centre of ptetion occurred only in 0.96％.