Traumatic L5 Posterolateral Spondyloptosis: A Case Report and Review of the Literature

Abstract

Traumatic retrolisthesis of the lumbar spine is a rare clinical entity. Only a few case reports have shown retrolisthesis of the fractured fragment over the inferior vertebral body. Fracture dislocations of the spine are unstable injuries that require operative fixation to restore alignment and prevent progressive deformity. We present the case of a traumatic L5-S1 fracture dislocation with retrolisthesis of the L5 vertebral body over the superior aspect of S1 managed with anterior, middle, and posterior column reconstruction. The patient presented with paraplegia and bowel and bladder incontinence. Retrolisthesis fracture dislocations injuries are rare, and as such, there are no guidelines regarding their management. In our case, we performed an L5 vertebrectomy with anterior, middle, and posterior column reconstruction via a posterior approach using a lumbosacral-pelvic construct. The patient did not regain function in his distal lower extremities postoperatively.

Keywords: fracture dislocation; retrolisthesis; spinal cord injury; spine; spine fractures; spondyloptosis; trauma.

Figure 1. Preoperative lateral x-ray

This is a preoperative lateral x-ray demonstrating a fracture dislocation with a posterior retrolisthesis of the L5 vertebrae over S1.

Figure 2. Preoperative anteroposterior x-ray

This is a preoperative anteroposterior x-ray demonstrating a fracture dislocation of the L5 vertebrae relative to S1. There is significant lateral listhesis apparent.

Figure 3. Preoperative parasagittal CT

This is a preoperative parasagittal CT demonstrating a fracture dislocation with posterior retrolisthesis of the L5 vertebrae over S1.

Figure 4. Preoperative parasagittal MRI

This is a preoperative parasagittal MRI showing gross ligamentous instability and complete obliteration of the thecal sac at the level of injury.

Figure 5. Intraoperative fluoroscopy

Intraoperative fluoroscopy showing fixation of the spine from L2 to the sacroiliac joint. An interbody cage was placed at the L5 level to provide anterior column support.

Figure 6. Intraoperative in-situ photograph

This is an intraopertaive in-situ photograph of the fractured L5 vertebral body (image left). The spinous processs of the L4 vertebrae is at the top of the image.

Figure 7. Intraoperative photograph

This image shows elevation of the dislocated vertebral body via a posterior incision.

Figure 8. Bony fragment

This is a photograph of the vertebral body after en-bloc removal.