We present a series of four U-shaped sacral fractures, a fracture pattern that is poorly recognised and not included in the standard classifications of these fractures. These fractures are significant as they represent spino-pelvic dissociation, have a high incidence of neurological complications and information regarding current treatment options is sparse. Our four patients underwent early operative stabilisation. Three had ilio-sacral screws inserted, supplemented in one with instrumentation from the lumbar spine to the iliac crest following sacral laminectomy. The other patient had sacral laminectomy with bony stabilisation by instrumentation from the lumbar spine to the iliac crest without ilio-sacral screw fixation. No complications were encountered as a result of fixation and it contributed to the prompt skeletal stabilisation of polytraumatised patients allowing early mobilisation.