Image-guided anterior cervical corpectomy - A feasibility study

Study Design. A feasibility study was performed to determine the efficacy o f using image-guided frameless stereotaxy to perform anterior corpectomy of the cervical spine. Objective. To assess the feasibility of using image-guided stereotaxy in pe rforming anterior cervical corpectomy. Summary of Background Data. Anterior cervical decompression including disce ctomy and corpectomy is a commonly performed procedure. Particular concern about invasion of the vertebral artery arises while performing this procedu re to gain maximal lateral decompression. At present, surgeons have only la ndmarks and experience to guide them in performance of this potentially dan gerous procedure. Methods. Four cadavers (average age, 40.3 years) were used. A lateral corpe ctomy trough was created in Group 1 by a standard technique using visual la ndmarks. In the second group of corpectomy troughs, an image-guided framele ss stereotactic system was used. After completion of the experiment, each c adaver had a corpectomy trough at every level on one side performed in a st andard manner and on the other with image guidance. Using the image guidanc e system, an independent observer measured the distance from the corpectomy trough (lateral border) to the medial border of the foramen transversarium . Results. The average distance from the lateral border of the trough to the medial border of the foramen transversarium in the standard trough group wa s 5.10 mm (range, 1.72-7.71 mm), and the average distance from the medial b order of the foramen transversarium to the image-guided trough was 4.34 mm (range, 3.34-5.48 mm). The trend of the comparison between the two troughs was toward significance at P = 0.08. Conclusions. Image-guidance provided improved accuracy when compared with t hat of a standard technique, implying clinical potential for image-guided c orpectomy. Less variability is seen using an image-guided approach.