SI joint dysfunction
  • Given that the anatomical research tells us that the SI joint provides only millimeters (yes millimeters) of motion, how is it that we (PT's) believe that we can see and palpate substantal "upshifts" and "ilio torsions" (anterior/posterior torsions)?
  • I think we can see ilio torsions because while the SI joints only move millimeters it would make sense that the movement is amplified when observed at the ASIS due to the distance between the SI joint and the ASIS (approximately 5-6" as I just measured my wife who is quite petite).

    Imagine your goniometer: with several millimeters of motion close to the axis there is much more distance between the arms of the goniometer at 5-6" away from the axis. Also, we must remember that in females where we often observe the most profound SI joint problems; the ligamentous laxity due to circulation of relaxin during the monthly cycle and during pregnancy may allow more motion. This must be the case during birth for the female pelvis to be able to spread and a child to pass through the birth canal. Just my thoughts.
  • Chad makes a key observation. While the literature tells us that the movement in the actual SI joint (between ilium and sacrum) is only millimeters, the linear translation farthest away from the axis of rotation will be much greater than the linear translation near the axis of rotation. This is analogous to the huge advantage our muscles have to create large movement paths of the hands and feet. A muscle at the elbow for instance (biceps) may shorten only a centimeter, but this will result nearly 10 times the translation of the hand in space because the hand is so far from the axis of rotation. So, a minimal movement in the SI (2mm) might be palpated at the ASIS or PSIS as 10mm because of the distance of these boney prominances from the actual SI joint. Thanks Chad.
  • A further observation about SI joint dysfunction with post-op THA patients. Recently saw a 58 y.o. female who underwent left THA 13 months ago. No "back" problems prior to surgery. Post-op she developed left sciatica and "low back pain". Pt. also had a noticeable leg length discrepancy following surgery over >1". The surgeon measured leg length and found less than 1cm difference on x-ray (well within acceptable tolerances).

    Patient went through one course of PT and also received injections from a physiatrist but, symptoms persisted. The patient ended up in my office. She presented with left SI joint pain, severe spasm of the left piriformis, a left down slipped innominate. Pain at time of exam was 7-8/10. Leg length was measured and found to be 2.2 cm discrepancy at time of exam (left longer). Patient also reported that radicular symptoms had been present that day extending poster-laterally to the level of her knee.

    Following Left SI joint mobilization using manual therapy muscle energy techniques patient's pain was diminished to 4/10, leg length was within 1cm of the right and radicular symptoms had completely disappeared. Pt. was limited with twist test to the left prior to treatment and noticeable improvement was noted following treatment.

    Pt. was re-examined at 1 week post initial treatment and pain had continued to diminish to 2-3/10 and was more periodic than constant.

    The point of this lengthy post is that I think that SI joint dysfunction and related issues resulting from THA are more common than most think. I think that the patient most likely suffered this SI joint problem as a result of the traction placed on her left lower extremity when disarticulating the left hip during THA. This problem was undiagnosed for over 1 year and patient received ineffective treatment for a problem in her lumbar spine that may or may not have been present. Bottom line is that her symptoms and her leg length discrepancy did not resolve until her SI joint problem was treated.

    Further food for thought!

Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

In this Discussion