Variable morphology of the sacrum in a Chinese population.

Although several morphological variations of sacrum have been reported in western populations, little attention has been paid to this anatomic issue in eastern people, and classification of sacral variability in particular. In this research of sacral morphology in Chinese people, we investigated and measured thoroughly and systematically 203 specimens of intact dry Chinese adult sacra. Morphological features of sacral variations were observed by visual inspection, and correlation parameters of variability were measured with a vernier caliper. The incidence of sacral variations was calculated. We found that the overall rate of sacral variations was 58.1% (male: 57.4%; female: 59.5%). The anatomical variants that we observed fell into the following five categories: accessory auricular surface (25 specimens, 12.3%); sacral skewness (48 specimens, 23.6%); transitional vertebra (34 specimens, 16.7%); sacral spina bifida occulta (57 specimens, 28.1%), Degrees I, II, and III of which were 36, 14, and 7 specimens, respectively; multiple variations (42 specimens, 20.7%), the types of which were diversified. This study reveals that sacral variations are common in Chinese population. The sacral variants in anatomic morphology should be taken into consideration when diagnosing and treating sacrum-related diseases. Copyright 2009 Wiley-Liss, Inc.