Sacroilliac joint pain

Patient: 2 weeks ago i had radiofrequency nerve ablation for left side sacroilliac joint pain. I felt fantastic after, pain free. After a week though the pain has come back. How is that possible when the nerves have been burnt away? Feeling in lots of pain now and so frustrated

Symptoms: Pain in both sides of lower back, and severe pain in both hips, also occasional muscle spasms across the lower back