Next to femur - that's hardly decent (4,3,4)
I believe the answer is:
near the bone
'femur that's hardly decent' is the definition.
I know nothing about this answer so I can't judge whether this works.
'next to' is the wordplay.
I cannot quite see how this works, but
'next to' could be 'near' (I've seen this in another clue) and 'near' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for near the bone that I've seen before include "Been on earth (anag) - risque" , "On the verge of indecency" , "Where flesh is" , "Pointed remark" , "almost indecent" .)