Morphological and biomechanic characters of the sacrum fractures
- VernacularTitle:骶骨骨折的形态学特点及生物力学研究
- Author:
Ren-Fu QUAN
;
Disheng YANG
;
Yijin WANG
;
- Publication Type:Journal Article
- Keywords:
Sacrum;
Lumbosacral plexus;
Biomechanics;
Morphology
- From:
Chinese Journal of Trauma
1993;0(06):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To discuss morphology and biomechanics of the sacrum fractures so as to provide scientific basis for corresponding clinical treatment. Methods A total of 10 fresh pelvis specimens were collected for dynamic impact test and static destruction test, in the former one of which, the dynamic parameters were measured to make sure the dynamic characters of the fractures. Meanwhile, the fractures of the sacrum wing, the sacral foramina and the sacrum edge were made decalcification, slice of paraffin wax and staining (Masson, Mallory, HE) in order to make a cytological observation of the tissue. Results (1) The form of sacrum fracture or acetabulum fracture, crista iliaceis fracture was relevant to the impact energy. Low impact energy usually caused fractures of the ilium, acetabulum or sacroiliac crest. High impact energy resulted in following three kinds of fractures, just as the classification of Denis: sacral ala fractures belonged to typeⅠfractures, sacral hiatus fractures to type Ⅱ fractures and central vertebral canal fractures to type Ⅲ fractures. All three types of fractures might involve lateral or bilateral nerve roots. (2) There was a significant mechanic difference in regard of the mechanism of both dynamic destruction and static destruction of pelvis, ie, not only the limit pressure differed but also the former increased rapidly with the higher rate of the strain. The clash energy beyond 25 J would beget the cleft fractures of the sacrum via sacrum hiatus and even involve the nerve roots. The clash energy under 20 J usually resulted in fractures of the ilium and the sacrum. The clash energy between 20 J and 25 J more easily caused type Ⅰ fractures. While fracture of the ilium and the acetabulum would happen most in static destruction. (3) The cross section of the sacrum was cracked and the bone board of Haversian system is brittle, as led to separation of bone board and malposition of a few cross bone boards. Conclusions Under dynamic state, the sacrum fractures mostly belong to type Ⅰ and type Ⅱ (Denis classification of sacral fractures), usually involving the nerve roots. The sacrum fracture is relevant to the microstructure, the distribution of the bone trabecula, the osseous lacuna and the Haversian system of the sacrum. The fractures of the ilium and the acetabulum more frquently appear in static state, with slight wound of peripheral tissues.
