Suggest Treatment For Severe Pain In The Groin Area

I am experiencing intermittent jabbing pain in my right groin area. Went to a pain specialist MD and he thought the cause was a ligament. But I did not ask nor he offer what ligament, and I forgot to ask whether or not exercise might be a good idea. He did give me a prescription for a compounded gel to administer 3 times per day, which I am picking up later today (has taken 5 days to make this gel), so I have not started this treatment yet. And, I have asked and received Rx for physical therapy, for myofascial treatment x6. Pain jabs when I have been in one position and move to another. Especially when I move into flexion, and occasionally when I am standing and I slightly rotate the leg inward or outward. This right hip is a replacement which I got about 2 1/2 years ago. Questions: what is likely ligament? How long does this go on? Sorry I didn't get to ask my dr, I don't see him again for a month. I am 74 year old woman.