ebirt og wrote:
I had a similar problem on and off for 2 years. Pain would switch sides periodically, but was more on the right side. Initially diagnosed with piriformis and glute muscle issues. ART always helped, but it never was gone.
Eventually I saw a PT would did a gait analysis (She has a Masters in Biomechanics). Turns out my left glute was weak, so my right hip would dip with every stride. After some work on tight muscles, I was given a strengthening program. Pain free for 6 months. It comes back a bit now when I skip the exercises for a few weeks. Try the exercises from a previous poster. There was an article in Runner's World sometime last year or get someone who knows what they are doing evaluate your stride.
This is by far the most valuable post you've gotten. Also, one question is are you referring to the lateral side of your buttocks? Because some posters have mentioned SI-joint although the pain you describe sounds more like glute medius and tfl related than towards your sacral area. I am trying to get a better idea of where the discomfort is.
The gait ebirt og (go tribe?) is describing sounds a like like Trendelenburg gait. I suspect if you were tested, you would test positive at least on one side, if not both (if it's a general weakness chances are you have it on both sides although one might be worse). The problem is, although it IS an indicator of weak hip abductors, it's also a very general test used to determine hip dysfunction. If you are lucky, that dysfunction is more soft tissue related and can be remedied by seeing the right PT (such as ebirt og)and developing a stretching and strengthing routine. However, if that does NOT show improvements, it's time to see a hip specialist. Either way, it sounds like you need a structured intervention so you don't get in a cycle of taking 2-3 days off, then running 1-2 days with progressive pain/discomfort.