Muscle pain and sore legs n buttocks after fat transfer, is this normal?

Thank you for your question, it is very unlikely that your muscle soreness is related to the procedure done 8 months ago, perhaps its due to hard workouts or strenuous activity.

Soreness and pain in the legs are very nonspecific symptoms. I would be surprised if those symptoms are related to surgery done over 6 months ago.However to make sure please see your primary doctor or your plastic surgeon.

It is unlikely that muscle soreness and pain is related to a surgical procedure of the buttocks about 8 months ago, but it is possible.  If concerned see your surgeon and if he feel it is not related, perhaps he can refer you to the right doctor.