I have recently started training a 41 year old female with extreme SI joint pain. She has suffered with this for the past 20 years and has come to the conclusion that she will just deal with it instead of constantly trying to find a solution. She works from her home and has designed her living and work area to accommodate the fact that she can not sit. She works at her computer standing, eats meals standing and can sit on the edge of a hard chair for short durations during a television program. At this point, we are just doing some core work with the BOSU and using the TRX for upper and lower body training. I am afraid of doing any type of twisting or back exercises and am not sure exactly what I should specifically work on. On the other hand, she has not hired me to help her fix this. She has hired me to help her stay in shape and be fit. Do you have any suggestions of specific safe exercises?
Many people report "SI" pain, but this is usually a location descriptor rather than a diagnosis - the pain is in the low back on either side of the spine over the SI joints. Quite often, this is not pain from the joint. Your description of her being intolerant to sitting (probably flexion intolerant) would suggest more discogenic pain. This often radiates over the SI joints. This response is not an attempt at diagnosis but rather shows a thought process in designing the best therapeutic exercise. I suspect your client would tolerate neutral spine stabilization exercises (such as the curl up, side bridge and birddog) as a start. The book Ultimate Back Fitness and Performance shows several progressions beyond basic stabilization. There have been a couple of efficacy papers recently showing the effectiveness of this approach for these types of people. Finally, excellent trainers also use these tests to determine the mechanical cause of the back troubles and then show the client how to remove them. This is half the battle - no exercise will work if the cause continues. Usually lumbar cushions while sitting are very helpful for the flexion intolerant back. Be careful of cycling posture, if the client partakes in these sorts of activities. Have her keep a diary of how her back is feeling each day together with the activities. Then go back and look at the activities of the previous day, and you should have more clues as to what helps and what hurts.
If you would like to do more research in this area, an excellent resource for you to invest in is Gary Gray's Functional Video Digest on the SI Joint.