tess the yorkie - poorly leg

my nans yorkshire terrier has always had probs with her back legs she always seemd bow legged, 2 years ago while on the beach she sumbled and tore all the ligaments in her back left leg, she had to have a major opp to fix it and they left a permanent metal bit in her leg. she came through it all well was stiff for a while but this year it wasnt cauing her any probs, but today she is really limping on the same leg its like shes donte the injury all over again, can it happen again even witht the metal plate in? shes off to vets on monday to have it checked

she's becoming the worlds most expensive pooch it cost over a grand the last operation:shock:

lisa