Magnetic resonance imaging of the musculoskeletal system: the spine.

Magnetic resonance imaging in the patient who has had surgery is discussed. The most common indication for postoperative imaging is in the distinction between postoperative fibrosis and recurrent disc herniation. Magnetic resonance imaging is invaluable in the assessment of potential causes of failed back surgery syndrome such as postoperative infection, arachnoiditis and adjacent segment degeneration. Magnetic resonance imaging assumes a less important role in postoperative patients with metal hardware owing to image degradation secondary to metal artifact. Magnetic resonance imaging has a complementary role with computed tomography evaluation of spinal trauma. It excels at the noninvasive evaluation of spinal deformities and neoplasms.