To disrupt an adult pelvic ring completely, forces as high as 10,000 newtons are needed. The loading forces on the ventral hemipelvis are lower than on the dorsal hemipelvis accordingly, the bones in the ventral hemipelvis are smaller and more easily broken. In the ventral hemipelvis, the pubic bone and ischium are connected at the symphysis pubis. The body weight is transferred from the lumbosacral spine via the dorsal hemipelvis to the hip joints and the lower extremities. In the dorsal hemipelvis, the sacrum is connected to the iliac bones by the ventral, interosseous, and dorsal ligaments. It is divided into the dorsal and ventral hemipelvis. The pelvic ring is the strongest and largest osteoligamental complex of the human body. Pelvic ring injuries in adolescents and adults New treatment strategies adapted to the specific problems of osteoporotic bone and high strain are presented. This manuscript provides an overview of osteoporotic pelvic ring insufficiency fractures and describes their spectrum of instability. Fracture patterns in the dorsal pelvis range from crush lesions in the lateral sacrum to spinopelvic dissociations. Additional computed tomography (CT) examinations are necessary to evaluate the dorsal pelvis. In most cases, conventional radiographs can detect only ventral pelvic fractures therefore, the severity of the injury is often underestimated. Osteoporotic and insufficiency fractures result from low-impact trauma, and multiple injuries are rare in these patients. Their mechanism of trauma, symptoms, and treatment differ from those of other types of adult pelvic ring injuries. Today, because of increasing life expectancy, we are confronted with a growing incidence of both osteoporotic and insufficiency fractures of the pelvic ring. The type of definitive treatment depends on the localization of the lesions and the amount of instability. Treatment consists of an emergency stabilization, which is part of the resuscitation protocol, and a definitive fixation. Classification is related to the direction from which the impact on the pelvic ring came and the degree of instability. Very often, soft tissues inside the small pelvis and around the pelvic ring are also disrupted. Such high forces are generated in traffic accidents, crush traumas, and falls from great heights. A force between 2,000 and 10,000 newtons is required to disrupt an adult pelvic ring.
Pelvic ring fractures typically result from high-energy trauma.
Angular stable bridge plating, the insertion of a transsacral positioning bar, and iliolumbar fixation are operative techniques that have been adapted to the low bone mineral density of the pelvic ring and the high forces acting on it. Therefore, vertical sacral ala fractures, fracture dislocations of the sacroiliac joint, and spinopelvic dissociations are best treated with operative stabilization. However, in some patients, an insidious progress of bone damage leads to complex displacement and instability. Most osteoporotic fractures are minimally displaced and do not require surgical therapy. The current well-established classification of pelvic ring lesions in younger adults does not fully reflect the criteria for osteoporotic and insufficiency fractures of the pelvic ring.
Fractures may be located in both the ventral and the dorsal pelvic ring. The clinical picture is dominated by immobilizing pain in the pelvic region. The patients have no signs of hemodynamic instability and do not require urgent stabilization. Such fractures are the result of low-impact trauma. The number and variety of osteoporotic fractures of the pelvis are rapidly growing around the world.