why however the trochanteric fossa of femur bone is a site for attachment of muscles is not eminence or ridge?

Answer 1

To my knowledge, there is not a trochanteric fossa. There is not mention of it in my textbook.

However, here are some definitions that may help you:

Fossa - a depression, often an articular surface

eminence - a protuberance or projection on a bodily part and especially a bone

ridge - an elevated body part projecting from a surface


The lesser and greater trochanters are considered projections, which serve as sites of attatchments for thigh and buttock muscles.