Abstract
Aims. to investigate whether the stability of partially unstable pelvic fractures can be improved by combining plate þxation of the symphysis with a posterior sacroiliac screw. Methods: In 6 specimens a Tile B1 (open book) pelvic fracture was created. We compared the intact situation to isolated anterior plate þxation and plate with SI screw þxation. Using a 3-dimensional video system we measured the translation and rotation stiffness of the þxations and the load to failure. Results: Neither absolute displacements at the os pubis or at the sacroiliac joint or stiffness of the ilium in respect to the sacrum were signiþcantly different for the techniques with or without sacroiliac screw or the intact situation. Load to failure was only reached in one of the six cases. In all other cases the þxation of the pelvis to the frame failed before failure of the þxation itself. In these cases a load of about 1000N or more could be applied. Conclusions: The addition of a sacroiliac screw in a Tile B1 fracture does not give signiþcant additional stability. Although cyclic loading was not tested, in these experiments forces could be applied similar to full body weight. Clinical experiments into direct postoperative weight bearing are recommended to examine the clinical situation.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
