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It is a mitzvah to burn any meat that passed its deadline and became nosar. The official time for this burning is only on the morning in which it became nosar. It cannot be burned at night. However, since this burning does not override the laws of Shabbos and Yom Tov, any leftover meat of the korban Pesach along with its sinews and bones are burned in the courtyards of Yerushalayim on Nissan 16, the first day of Chol Hamoed in Eretz Yisrael.
Even though Rav says that sinews are not considered meat, Rebbi Yochanan argues with Rav and says that they are considered meat. Rebbi Yochanan apparently maintains that although they are hard, since they can be softened through boiling they are considered meat, like the ligaments mentioned in the Mishnah.
Why do Rav and Reish Lakish rule that the sinews of the neck are not considered meat, even though they can be softened through boiling? Apparently, Rav and Reish Lakish maintain that cooking the sinews of the neck does not soften them sufficiently, and thus they are not comparable to the Gidin mentioned in the Beraisa which become completely softened through cooking.
What are giddin? Are the sinews of the neck different, we discuss the talmudic account of bones, sinews and tendons, which leads bas to the work of Asaph Harofeh the Person Jewish Physician who cites Hippocrates.