Pelvic fractures occur from high energy mechanisms, such as MVCs, but can occur in the elderly from seemingly minor falls.  

Ring structures, such as the pelvis, mandible, and C1 vertebrae, tend to disrupt in more than one location.  An exception is low velocity falls in the elderly, in which pubic ramus fractures often occur in isolation. 

Classification of pelvic fractures (which is beyond the scope of this brief document) is based on the direction of the injuring force and likely complications.