THE USE OF COLOR DOPPLER IMAGING FOR THE ASSESSMENT OF SACROILIAC JOINT STIFFNESS - A STUDY ON EMBALMED HUMAN PELVISES

Purpose: The validity and reproducibility of an instrumented dynamic e xamination method to measure sacroiliac (SI) joint stiffness was teste d in vitro. Methods: Four embalmed human female pelvises were excitate d by a pelvic vibrator, A color Doppler imaging (CDI) scanner was used to image the amplitude of vibrations at different sites of the pelvis . Vibrations were applied to the anterior superior iliac spines unilat erally and were received by CDI all over the ipsilateral SI region, Th ree different stability conditions were created in the SI joints: no i ntervention, screwed and ligaments cut. Test results were quantified b y taking the minimum threshold levels of the bones, The relative diffe rence of vibration intensity between ipsilateral ilium and sacrum at e ach stability condition is accepted as the stiffness level for the SI joint. Results: Statistics showed high reproducibility and significant differences between the stability conditions. Dynamic testing based o n the use of vibrations provides visible and quantifiable intra- and i nter-individual differences between SI joint stiffnesses, Conclusions: This new method is objective and reproducible. Future in vivo applica tion is promising since there are no technical and safety restrictions .