Titanium Wire Internal Fixation for Stabilization of Injury of the Cervical Spine: Clinical Results and Postoperative Magnetic Resonance Imaging of the Spinal Cord

Abstract

Abstract Nine patients with dislocation of the cervical spinal with posterior ligamentous damage were treated with posterior internal fixation using a twisted pair of 22-gauge titanium wires and iliac crest bone fusion. Fixation using the titanium wire was compared with fixation using stainless steel wire for differences in surgical insertion, long term stability of bony fusion, and postoperative magnetic resonance imaging (MRI) artifacts near the implanted wire. MRI of the cervical spine is valuable for diagnosing the acute and chronic consequences of traumatic cervical spinal injury by providing anatomic evaluation of both the spinal cord and the supporting bony/ligamentous structures in the neck. Because MRI is an accurate and sensitive noninvasive test, it is especially useful for the long-term serial assessment of the region near the cervical dislocation site to detect the sequelae of spinal cord injury, including syrinx, arachnoid cyst, cord tethering, and persistent mechanical impingement on the spinal cord or spinal roots. Previous attempts at our institution to obtain useful MRI scans of the cervical region adjacent to stainless steel wires after posterior wire fixation have failed due to marked imaging artifacts arising from the ferromagnetic properties of these wires. Our substitution of biocompatible titanium wire (Titanium 6 A1-4V ELI alloy, Specialty Steel and Forge, Leonia, New Jersey) for stainless steel wire produced identical immediate stabilization and ultimate bony fusion of the fracture and yielded minimal MRI artifacts overlying the immediately adjacent spinal cord and neural canal; however, the installation was technically more difficult, because of the titanium wire's greater stiffness. We believe that the implantation of a permancent fixation device in these patients should be made of an MRI-compatible material, such as titanium wire, to allow serial imaging with MRI in their lifelong medical care.