[Biomechanics and imaging evaluation on stable structure of pelvis]

The treatment of difficulty and prognosis of pelvic fracture are directly related to the pelvic girdle stability. Diagnosis of pelvic fracture is mainly imaging manifestations based on biomechanics of pelvic anatomy. With the progress of biomechanics experiment technology, previousopinion has changed, such as separation of symphysis pubis 2.5 cm could not be seen as distinguishing feature of type I and II for anterior-posterior compression;displacement of sacroilliac joints less than 1 cm could cause loss of vertical stability;lateral extrusion could also cause vertical instability;part description of Young-Burgess classification is not suitable for experiment results;ligament plays an important role in restricting displacement and having proprioceptors;SPECT-CT could improve sensitivity of diagnosis, but could not evaluate stability of pelvic fractures precisely.