الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Due to the high energy required to disrupt the pelvis, pelvic ring injuries are only part of a spectrum of polytrauma with significant morbidity and mortality. The anatomy of the pelvis as a ring structure makes an isolated disruption in one part of the ring unusual. ring structure consisting of the sacrum and the two innominate bones. It encases important visceral structures and serves as a link between the axial skeleton and the lower extremities. While the pelvic ring lacks inherent bony stability it is held together by a network of interosseous ligaments. Anteriorly, there are the public symphysis and the anterior sacroiliac (SI) ligaments, which collectively contribute about 40% to the stability of the pelvis. Posteriorly, there are the much stronger posterior SI, sacrospinous, and sacrotuberous ligaments. These posterior ligaments form a suspension bridge that maintains the position of the sacrum within the pelvic ring.
Additional stability is provided by the iliolumbar and lumbosacral ligaments. Collectively, the aforementioned ligaments stabilize the pelvic ring by resisting rotationally and vertically applied deforming forces. The transversely oriented anterior SI and sacrospinous ligaments more effectively resist rotation, whereas the vertically oriented sacrotuberous ligaments help prevent vertical displacement. The posterior SI ligaments, on the other hand, consist of short transverse and long vertical fibers, and therefore resist both rotational and vertical deforming forces. The two most commonly used classification systems for pelvic ring injuries are those described by Tile and Young-Burgess Classifications systems can help predict associated injuries and resuscitation requirements.
Plain x-rays, computed tomography ,3D C.T.are the most common radiological methods in the assessment of the pelvic fractures. However the C.T. in considered the golden standard in this type of injuries as it gives great help in the diagnosis and management plans.
Hemodynamic instability occurs in about 10% of pelvic ring injuries. Bleeding usually originates from cancellous bone, presacral venous plexus, and/or iliac vessels. Extrapelvic hemorrhage can also occur due to the often high-energy trauma required to disrupt the pelvis, with long bones and abdominal viscera being the most common sites.
The incidence of associated long bone fractures in unstable pelvic ring injuries has been reported to be over 80%.While the severity of the injury pattern correlates with blood transfusion and fluid resuscitation requirements, hemorrhagic shock can occur in both stable and unstable patterns, and is the most common cause of death in the first 24 h. Immediate recognition and treatment of this life-threatening complication is the most important factor for survival.
The criteria for hemorrhagic shock are variable, but are often based on presence of either a systolic blood pressure <90 mmHg or an acid base deficit < _6 mmol/L. Additionally, hemoglobin level ≤10 g/dL within the first 30 min of arrival may indicate significant bleeding. Aggressive resuscitation is required in these circumstances in accordance with the Advanced Trauma Life Support (ATLS) protocol.