Using a three-dimensional (3D) image-guided system to help place screws in the spines of patients results in safe and accurate surgery with a decrease in the number of misplaced screws, and subsequent injuries, seen in more traditional operations, say neurosurgeons at Mayo Clinic in Florida.
In the Dec. 9 online edition of the Journal of Neurosurgery: Spine , Mayo physicians published the largest study yet using 3D image-guided technology to place screws in the spine for spinal fusion procedures. The screws are used to stabilize the spine in patients who suffer from collapsed discs or compressed nerves.
Specifically, after implanting 1084 "pedicle" screws in 220 patients, surgeons reported a nerve injury rate of less than 1 percent. Additionally, less than 1 percent of the screws in this study were considered to be significantly misplaced. That compares to a reported nerve injury rate of up to 8 percent and a misplacement rate of up to 55 percent using standard technology. As well, re-operation for removal of a misplaced screw has been reported in other surgical literature to be as high as 6.5 percent but occurred in less than half of one percent of all patients in the Mayo study, according to the researchers.
"Using 3D image-guided technology to help us place these screws results in a much better outcome for our patients," says Mayo Clinic neurosurgeon Eric Nottmeier, M.D., the study's lead investigator. "In addition to the decreased incidence of nerve root injury, this technology allows us to place larger screws into the spine, which can also increase the success rate of the operation."
The technology uses a special camera on a computer that uses infrared light to track a surgical instrument in 3D space. The surgeon places the instrument on the patient's spine and navigates the spine using the computer. The surgical instrument is used to determine the best entry point and trajectory for each screw. An image-guided screwdriver is used to place a screw.