Bilateral High Division of Nervus Ischiadicus: A Cadaveric Case

Abstract

Nervus (n.) ischiadicus is a large nerve arising from the gluteal region and extending toward the posterior locations of the femur. It divides into two terminal branches on the proximal point of fossa poplitea: n. tibialis and n. peroneus communis. N. ischiadicus supplies somatic motor fibers to muscles in the feet, legs and posterior locations of the femur, while also providing sensitive fiber to a large part of leg skin and feet. N. ischiadicus was found to have a different course in the dissection performed on the bilateral gluteal region of the case in this study, the cadaver of a male person aged 55. The course of n. ischiadicus is a single branch in the gluteal region but it showed two branches in the case of this study. This course was found to be a bilateral example of Type b based on the classification of Beaton and Anson. It is important to know the course of this nerve for the surgical interventions to be made on this region considering the interaction between n. ischiadicus and other anatomical structures.

Keywords

• cadaver;
• variation;
• n. ischiadicus;
• n. tibialis;
• n. peroneus communis.

Nervus Ischiadicus Bilateral Yüksek Ayrılması: Kadavra Çalışması

Öz

Nervus (n.) ischiadicus, gluteal bölgeden çıkan uyluk arka bölgede seyreden kalın bir sinirdir. Genellikle fossa poplitea’nın üst ucunda iki terminal dala ayrılır. Bunlar n. tibialis ve n. peroneus communis’tir. N. ischiadicus ayak, bacak ve uyluk arka bölgede bulunan kaslara somatomotor lifler, bacak derisinin büyük bir bölümüne ve ayağa sensitif lifleri yollar. Bu olguda 55 yaşındaki erkek kadavranın bilateral olarak yapılan gluteal bölge diseksiyonunda n. ischiadicus’un farklı seyrettiği görülmüştür. N. ischiadicus’un seyri gluteal bölgede tek dal olarak beklenirken iki dal halinde olduğu kaydedilmiştir. Beaton ve Anson sınıflandırmasına göre bilateral olarak tip b’ye örnek olduğu görülmüştür. N. ischiadicus’un bu bölgedeki diğer anatomik yapılarla etkileşiminden dolayı buraya yapılan cerrahi girişimler açısından seyrini bilmek önemlidir.

Anahtar Kelimeler

• kadavra; varyasyon; n. ischiadicus; n. tibialis; n. peroneus communis

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