Magnetic resonance imaging after pedicular screw fixation of the spine.

Magnetic resonance imaging (MRI) of the thoracolumbar spine is valuable in the diagnosis of acute and chronic spine injuries. It allows evaluation of the nerve roots, spinal cord, and the supporting bony and ligamentous structures. Magnetic resonance imaging can be used to detect sequelae of spinal cord injury and any mechanical impingement on the spinal cord or nerve roots. Pedicular screw fixation of the spine is becoming the procedure of choice for stabilization of the lumbar spine, yet it limits the postoperative use of MRI because of marked imaging artifacts arising from the ferromagnetic properties of the used stainless steel implants. The authors have compared extensive artifacts produced by the stainless steel implants with those produced by titanium implants. Titanium implants produced fewer artifacts in the spinal canal. The use of MRI compatible materials in thoracolumbar spine stabilization would permit detailed examinations by serial MR imaging.