Transverse fracture-dislocation of the sacrum: a diagnostic pitfall and a surgical challenge.

Transverse fracture-dislocations of the sacrum are rare. Associated lesions of the lumbosacral spine as well as neurological injuries are common. Conventional radiographs of the pelvis often fail to clearly visualize the fracture. Delayed diagnosis increases the risk of progressive neurological disfunction. True lateral sacral views and CT-scans with 3-dimensional reconstructions are very helpful in establishing the full extent of the injury. These examinations should be considered in all patients with a history of high energy trauma and clinical signs indicating lumbosacral injury, such as severe low back pain and neurological disturbances of the lower extremities. The management of transverse sacral fracture-dislocations with or without associated neurological damage is controversial. Conservative treatment is associated with a high rate of persistent deformity and residual neurological dysfunction. Surgical management allows for anatomical fracture reduction, stable fixation and revision of the spinal canal and lumbosacral nerve roots. The dorsal approach is preferred. Two patients with transverse sacral fracture-dislocations and neurological disturbances are presented. One patient had an additional fracture-dislocation of the lumbar spine at the L4L5 level with intrusion of the lumbosacral spine into the pelvis. Both lesions in this patient were successfully stabilized using an internal fixator system. The other patient presented with a bilateral transforaminal sacral fracture. The transverse component was not recognized on the initial radiographs, which resulted in loss of reduction and progressive neurological disfunction after sacroiliac screw fixation.