Sulak Osman, Sakalli Busra, Ozguner Gulnur, Kastamoni Yadigar
Department of Anatomy, Faculty of Medicine, Suleyman Demirel University, 32260, Isparta, Türkiye,
Surg Radiol Anat. 2014 Apr;36(3):265-72. doi: 10.1007/s00276-013-1179-0. Epub 2013 Jul 27.
The aim of this study is to determine the morphometric development, location and variant formations of the sciatic nerve using anatomic dissection method during the fetal period.
Sciatic nerves of 200 human fetuses (103 males and 97 females) aged between 9 and 40 weeks of gestation were studied bilaterally. The bifurcation level of the sciatic nerve to its terminal branches was evaluated with respect to popliteal fossa. Then the length of the sciatic nerve, starting from where it leaves the piriformis muscle till the bifurcation point of the nerve, and its width at the point where it leaves infrapiriforme foramen and its width at the bifurcation level were measured. We also measured the distance of the sciatic nerve to the ischial tuberosity, the greater trochanter and the intergluteal sulcus. Mean values and standard deviations of all parameters according to trimesters were calculated.
We found that all parameters increase with age during the fetal period (P < 0.05). Parameters do not show any significant differences between sexes (P > 0.05). In our analysis, we observed that in 98 % of the cases (on the right and the left side) the sciatic nerve leaves the pelvis below the piriformis muscle. The remaining cases (2 %) are variant formations.
We believe that our study will be useful for better understanding of sciatic nerve development and it may contribute to future studies in obstetrics, orthopedics and fetal pathology. Knowledge of variant formations of the sciatic nerve, its bifurcation level and its relation with neighboring structures may be important for blockade of the nerve in newborn surgeries.
本研究旨在利用解剖 dissection 方法确定胎儿期坐骨神经的形态计量学发育、位置及变异情况。
对200例孕龄在9至40周的人类胎儿（103例男性和97例女性）的双侧坐骨神经进行研究。根据腘窝评估坐骨神经至其终末分支的分叉水平。然后测量坐骨神经从离开梨状肌处到神经分叉点的长度，以及其离开梨状肌下孔处的宽度和分叉水平处的宽度。我们还测量了坐骨神经至坐骨结节、大转子和臀间沟的距离。计算各参数按孕期的平均值和标准差。
我们发现胎儿期所有参数均随年龄增加（P < 0.05）。参数在性别之间未显示任何显著差异（P > 0.05）。在我们的分析中，我们观察到在98%的病例中（左右两侧）坐骨神经在梨状肌下方离开骨盆。其余病例（2%）为变异情况。
我们认为我们的研究将有助于更好地理解坐骨神经发育，并且可能有助于未来在产科、骨科和胎儿病理学方面的研究。了解坐骨神经的变异情况、其分叉水平及其与相邻结构的关系可能对新生儿手术中的神经阻滞很重要。
