Suggest Treatment For Sacroiliac Joint Pain

Hello, I have constant pain in my left s.i. joint and across the lumbar region X 6 months. It is worsened when I stand or walk. It feels better when I am lying down and resting. In the past month, the pain had radiated to my hips, again, worse when I stand and especially when I walk. I also have some weakness in my left leg. The pain is better in the morning, and increases as the day progresses. I ve tried OTCs, ointments, stretches, self-massage. I only have negligible relief from these approaches. Thank you in advance for your assistance.