Re-starting a religious practice

Hi,

[Jewish law prohibits eating the gid hanasheh, a neurovascular bundle found in the hindquarters of an animal.]

In a community where the hindquarters of animals have been sold to non-Jews for generations, rather than expend the effort to remove the gid hanasheh, one who needs the hindquarters would be permitted to bring in a certified expert to remove the gid hanasheh. The non-practice does not constitute a minhag, and doing so could increase the number of Jews who opt for kosher meat over non-kosher meat.

(Rav Moshe Feinstein, Igrot Moshe Yoreh Deah 2:42)

Have a great day,
Mordechai