Tzarich Iyun: Nikkur Achoraim
Misconception:Nikkur achoraim (rendering the hindquarters of an animal fit for kosher consumption) is a Sephardic practice that is banned by rabbinic fiat for Ashkenazim and thus not performed in the United States
Fact: There is no such ban, and nikkur was practiced in many Ashkenazic communities into the twentieth century. The practice of some communities to refrain from eating hindquarters, owing to the difficulty in excising the forbidden sections, continues to exist among both Ashkenazim and Sephardim.
May an Ashkenazi Eat Sirloin?
“And Yaakov was left alone, and a man wrestled with him until daybreak. When the man realized that he was unable to defeat Yaakov, he struck the “kaf” of Yaakov’s thigh, which became dislocated as a result of the wrestling. And the sun rose as Yaakov passed Penuel, and he was limping because of his injured thigh. Therefore, the descendants of Yisroel do not eat the sciatic sinew to this very day, for the man struck Yaakov on that sinew, dislocating it” (Breishis 32:25-26, 32-33).