Thoracolumbar spine and pelvis plain radiography

Radiographic evaluation of the pelvis and spine often starts with plain radiographs, most commonly ordered after a traumatic injury. Because of the limitations of plain films in these areas, discussed in more detail later in this chapter, CT is often ordered to clarify an injury noted on a plain radiograph, or in caseswhere a high diagnostic concern exists. As with all plain radiographs, soft tissues are not well visualized. MRI may be ordered, especially in the spine to assess intervertebral disks, spinal nerves, and the spinal cord. Severe fractures of the pelvis often necessitate an angiogram to diagnose and potentially treat arterial or venous injury. The thoracolumbar spine is discussed separately fromthe pelvis in this chapter. Eachsection discusses indications, diagnostic capabilities, and limitations, followed by images of important pathological findings. THORACOLUMBAR SPINE Indications Imaging of the thoracolumbar spine is often ordered after injury. Patients with pain or tenderness over the spine, rather than the paraspinal muscles, or with high-risk injuries and unreliable exams should be imaged (1,2). Injury occurs less commonly in the thoracic spine due to its immobility and the additional stability provided by the rib cage. Most fractures occur at the junction of the thoracic and lumbar spine.