I recently discovered that my LEGO Legolas minifig from LEGO Lord of the Rings has two small cracks starting from the base of the torso on each side, but I wonder: will these cracks extend and damage the fig?
These cracks will often get worse over time as the legs are removed and replaced, or simply from normal play. Even if they don't get worse, the legs probably already have low clutch power which may be causing the legs to simply fall off.
Given that LEGO is still producing a Legolas minifig, they will almost certainly be happy to replace that torso for you. You can either find the piece that is broken and submit a replacement request to LEGO, or you can contact customer service directly and explain which piece is broken.
This really depends on how much you plan to use LEGO-las. If he's to be used just as a display or collectors item, he should be fine; to ensure safety, super-glue the poor elf's pants to his body.
If you plan to make him hop around and destroy orcs on a regular basis, try super-gluing the cracks from the inside while the pants are removed or it will get worse.
If the crack is too small to super-glue, I wouldn't worry till LEGO-las' legs get loose, which will happen if he is excessively used for play.