Intraoperative evaluation of implants in anterior cervical spine surgery by three-dimensional fluoroscopy.

Objective: Accurate radiographic documentation of the proper placement of cages, plates, and screws following cervical spine surgery significantly impacts clinical outcome. Postoperative computed tomography scans clearly show that the position of implants is sometimes far from ideal. The morbidity of anterior cervical disc surgery is well documented, but the incidence and influence of the misplacement of interbody spacers, plates, and screws are underestimated. We used isocentered fluoroscopy with three-dimensional image reconstruction intraoperatively to evaluate the extent of bony decompression and position of implants before wound closure.

Methods: From October 2003 through April 2004, 27 patients had anterior cervical procedures: 22 one-level and 5 two-level operations. Herniated cervical discs were diagnosed in 21 individuals, whereas 6 exhibited spondylosis. A radiolucent operating table made of carbon fibers was used in all patients. Before wound closure, intraoperative three-dimensional fluoroscopy was performed to evaluate the location of cervical implants and anterior bone resection.

Results: The entire scanning procedure required 5 minutes; the actual scanning time was only 120 seconds. In all patients, we were able to adequately evaluate the placement of cage, plates, and screws. Utilization of intraoperative three-dimensional fluoroscopy revealed that two cages were malpositioned and required revision before wound closure.

Conclusions: Intraoperative three-dimensional fluoroscopy is a valuable tool for the intraoperative imaging of bony decompression and implants in anterior cervical spine surgery. The technique is safe and reliable and should help us to avoid incomplete decompression or misplacement of implants and therefore improve long-term functional outcomes in the future.