'Within Ring' Concept Treatment for Displaced H-Shaped Type IVb Fragility Fractures of the Pelvis.

SIRF is useful because it can preserve the mobility in the lumbar pelvis; not including the lumbar spine in the fixation range like spino pelvic fixation is a simple, safe, and low-invasive internal fixation method for displaced H-shaped type IVb fragility fractures of the pelvis.