What Causes Severe Pain In Groin Area?

.I am very surprised in regards to the left pain in groin area. I too have had hysterectomy in 2008. This pain that comes and goes started 3 months ago. Dr. ran me thru a series of tests vaginal ultrasound and blood work. Everything is coming up negative. I was surprised to see that its not just me. So what is it? This pain is so strong that it buckles me right over like someone is stabbing me with a sharp object. I have degenerative bone disease so I already take pain meds and still the pain is there. If you ever find any conclusion to all this please let me know. Also since this started not sure about the rest of you but I feel really bloated all the time. Hope this helps. And I am 57. Thanks so much for a web site like this for you all to go out of your way to help people with health issues.