Question
Hello,We are sorry, but Dr. Brendon J. O`Brien, D.C. wasn't able to answer your question: I have a Cat 2 SI Joint strain treated by chiro. What I don't understand is I felt it go "pop" with very minimal pain. I was doing repetetive lifting of 7.1kg boxes and passing them sideways. I went home and still had minimal pain. I was able to work the next day as a registered nurse but the following day I was in pain and 3 weeks later still have it although is reducing now with chiro tx and massage. I don't understand why it took so long for this intense pain to come? In the past injuries I have had with my back I am aware straight away Unfortunately, not all volunteers are able to answer all questions. Feel free to repost your question to another volunteer by clicking on the link http://www.allexperts.com/browse.cgi?catLvl=3&catID=965

Answer
It sounds as if, coupled with the SI joint strain, you have a strain of the Psoas/Iliacus muscles.  It may have taken a day or so after overuse to flare.  It may have progressed this way if the muscles were overworked, and irritated, and somewhere along the line you did something that "pushed them over the edge".  Addressing the Psoas/Iliacus muscles may make a difference.  If you do a search for Psoas syndrome it can explain in much more detail than here.
Hope this helps