You may no longer have a painful joint. There are some risks when you have general anesthesia. Discuss these risks with your doctor. A regional anesthetic may not numb the area quite enough and you may feel some minor discomfort. Also, in rare cases, you may have an allergic reaction to the drug used in this type of anesthesia.
Regional anesthesia is considered safer than general anesthesia.
There is a risk of infection or bleeding. There is a risk of nerve or artery damage. There is a risk the bones will not fuse and you will need further surgery. You should ask your doctor how these risks apply to you. You are in a lot of pain.