Traumatic spinopelvic dissociation or U-shaped sacral fracture: a review of the literature.

Traumatic spinopelvic dissociation is a rare high-energy injury pattern, characterised by a transverse sacral fracture in conjunction with bilateral sacral fracture-dislocations. It has a high incidence of neurological complications. The true nature of the injury is easily missed and diagnosis is delayed because it commonly presents in patients with severe associated injuries. In the absence of diagnosis and treatment, it can lead to progressive deformity and chronic pain. Early realignment and fixation of the unstable lumbopelvic junction, with adjunctive decompression of compromised lumbosacral roots, are currently thought to provide the best possible environment for early mobilisation of the polytraumatised patient. Plain pelvic radiographs (anteroposterior, inlet, and outlet), lateral sacral radiograph, CT scan and reconstruction are essential to provide optimal imaging and understanding of the fracture pattern. There is no single treatment paradigm and various surgical strategies have been described in the literature. Lumbopelvic fixation or triangular osteosynthesis has recently been recommended by several authors to restore stability at the lumbosacral junction. This article presents a review of the incidence, clinical evaluation, treatment methods and outcomes of this injury pattern.