Departamento de Cirurgia, Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, BR.
Clinics (Sao Paulo). 2020;75:e1623. doi: 10.6061/clinics/2020/e1623. Epub 2020 Jul 10.
To verify the pyramidalis muscle's frequency (bilaterality, unilaterality, or absence) and morphometry (length of the medial border and width of its origin/base) in a sample of the Brazilian population and the anthropometric influence.
Dissection of 30 cadavers, up to 24h post-mortem.
The pyramidalis muscle was present bilaterally and unilaterally in 83.33% and 3.33% of the cadavers, respectively, and absent in 13.33%. The muscles on the right and left sides were symmetrical in length but not in width; the pyramidalis muscles of men were longer, while those of the women were wider. We also found that there was greater variation in the dimensions (length and width) of the men's muscles. Finally, in this sample of the Brazilian population, the pyramidalis muscle's unilaterality was more prevalent than in other populations, and its complete absence was less prevalent.
There were no cases of muscle duplication in one or both sides, as described in some studies. Despite all of its morphometric variation, the pyramidalis muscle maintained its triangular shape with longitudinal fibers in every case. Furthermore, no statistically significant correlation was noted between the muscles' dimensions and person's age, height, weight, or gender.
验证巴西人群中 pyramidalis 肌的出现频率（双侧、单侧或缺失）和形态（内侧边界的长度和起源/基底的宽度），并分析其与人体测量学的影响。
对 30 具尸体进行解剖，死后时间不超过 24 小时。
pyramidalis 肌在 83.33%和 3.33%的尸体中双侧和单侧出现，分别缺失在 13.33%。两侧肌肉的长度是对称的，但宽度不对称；男性的 pyramidalis 肌较长，而女性的较宽。我们还发现，男性肌肉的尺寸（长度和宽度）变化更大。最后，在这个巴西人群样本中，pyramidalis 肌的单侧出现比其他人群更为普遍，完全缺失的情况则较为少见。
与一些研究中描述的情况不同，我们没有在单侧或双侧观察到肌肉重复的情况。尽管存在形态学上的各种变化，但 pyramidalis 肌在每例中都保持了三角形形状和纵向纤维。此外，肌肉尺寸与个体的年龄、身高、体重或性别之间没有统计学上的显著相关性。
