Sad Days with Our Boston Terrier

I made this video to show our veterinarian the problems our little Sasha was experiencing. She winces in pain sometimes as she walks. We never found out what was wrong with her. The vet just prescribed pain killers and steroids. These helped for short period of times, but ultimately did no good. Sasha passed away a few months later. If anyone has any idea of the nature of her illness, please advise? Sasha was only 11 years old.