Cihan Ömer Faruk, Karabulut Mehmet
Anatomy, Gaziantep University, Gaziantep, TUR.
Anatomy, Selçuk University Faculty of Medicine, Konya, TUR.
Cureus. 2023 Jan 15;15(1):e33792. doi: 10.7759/cureus.33792. eCollection 2023 Jan.
Anatomical variations of the sacrum involve alterations in the number of sacral segments, auricular surface area, and neural arch dimensions and are associated with biomechanical, surgical, and obstetric implications. Due to the complex functional structure of the sacroiliac (SI) joints, it was aimed to evaluate their morphometric structure, classify the sacrum, and group different locations of the auricular surface in the sacrums.
Sex determination was made in 91 dry human sacra. Determination of the alpha angle on the sagittal axis of the auricular surface of the sacrum and classification of the auricular surface of the sacrum was performed. The sacra were studied to determine the position and extent of their auricular surfaces in relation to the sacral segments. Specimens were grouped as "normal," "high-up," and "low-down" auricular surface-bearing sacra. The sacral surface areas were measured, and SI joints were classified into three types morphologically (types I, II, and III). The depth and anterior-posterior length of the cranial, middle, and caudal impressions observed in the posterior sacrum and anterior-posterior lengths were measured.
The measurements made for sex determination showed that 46 of the sacra were from females and 45 were from males. The alpha angle on the sagittal axis of the sacral auricular surface was found to be greatest at the level of the first posterior sacral foramina. While the most common sacrum type was Type III, the least common type was Type I. The surface area of facies auricularis was found to be larger in males than in females. With regard to facies auricularis in all sacrum groups, although it covered approximately 2.5 sacral vertebrae, there was a difference in the location of facies auricularis in the sacral vertebrae. A statistically significant difference was found between right and left in the depth values of the impressions in the dorsal surface of the sacrum (p <0.05).
The position of the auricular surface in the sacrum differed among individuals. These differences are associated with variable load-bearing in the SI joints. The biomechanical classification of the sacrum and localization of the auricular surface can provide information about the anatomic source of low back pain or help predict the location of low back pain. Changes in the synovial surface morphology of the SI joints may elicit sacroiliac joint pain. This study was conducted because it is considered that the location of the auricular surface can significantly affect load-bearing patterns of the sacrum.
骶骨的解剖变异涉及骶椎节段数量、耳状面面积和神经弓尺寸的改变，并与生物力学、手术及产科方面相关。由于骶髂（SI）关节功能结构复杂，旨在评估其形态结构，对骶骨进行分类，并对骶骨中耳状面的不同位置进行分组。
对91块干燥的人类骶骨进行性别鉴定。测定骶骨耳状面矢状轴上的α角，并对骶骨耳状面进行分类。研究骶骨以确定其耳状面相对于骶椎节段的位置和范围。标本被分为“正常”、“高位”和“低位”有耳状面的骶骨。测量骶骨表面积，并将骶髂关节在形态上分为三种类型（I型、II型和III型）。测量骶骨后部观察到的颅侧、中间和尾侧压迹的深度及前后长度。
性别鉴定测量结果显示，46块骶骨来自女性，45块来自男性。发现骶骨耳状面矢状轴上的α角在第一骶后孔水平最大。最常见的骶骨类型是III型，最不常见的是I型。男性的耳状面面积大于女性。关于所有骶骨组的耳状面，尽管它覆盖了大约2.5个骶椎，但耳状面在骶椎中的位置存在差异。骶骨背面压迹深度值在左右之间存在统计学显著差异（p<0.05）。
骶骨中耳状面的位置因人而异。这些差异与骶髂关节中不同的负重情况相关。骶骨的生物力学分类和耳状面的定位可为下腰痛的解剖学根源提供信息，或有助于预测下腰痛的位置。骶髂关节滑膜表面形态的改变可能引发骶髂关节疼痛。进行本研究是因为认为耳状面的位置会显著影响骶骨的负重模式。
