Review Question - QID 5748

Figure C is an axial CT scan of a lateral compression type 3 (LC3) pelvic ring injury.

Classically, LC3 injuries demonstrate an ipsilateral lateral compression and a contralateral APC (windswept pelvis) fracture pattern. The most common mechanism of injury in these cases is a rollover MVC or pedestrian vs. auto. LC1 injuries are characterized by an oblique or transverse ramus fracture and ipsilateral anterior sacral ala compression fracture, while LC2 injuries consist of a rami fracture and ipsilateral posterior ilium fracture dislocation (crescent fracture). While LC1 injuries can often initially be managed conservatively with protected weight-bearing and close observation, LC2 and LC3 pelvic ring injuries are almost universally operative.

Pennal et al. discuss a radiologic technique for assessing the forces producing pelvic disruption and its use in logically classifying pelvic injury. Based on this radiologic assessment and along with some biomechanical studies, they propose a classification system involving three major forces producing injury that can also be helpful in the management of these patients.

Young et al. performed a retrospective analysis of the plain radiographs of 142 cases of pelvic fractures and identified four patterns of force that presented with distinctive, recognizable radiographic appearances. They describe a classification system for pelvic fractures based on radiographic and clinical findings that correlates with associated injury to soft-tissue structures and enables the surgeon to begin corrective procedures rapidly.

Incorrect Answers:
Answer 1: This represents a lateral compression type 2 injury.
Answer 2: This represents a lateral compression type 1 injury.
Answer 4: This represents an anterior posterior compression type 2 injury.
Answer 5: This represents an anterior posterior compression type 3 injury.