THE EFFECT OF PLACEMENT OF THE LP PRESTIGE DISC ON THE SEGMENTAL MOTION

Abstract

Introduction: There is an increasing interest in the concept of motion preservation in cervical disc degeneration surgery. There is still a controversy regarding the effect of posterior placement of the disc on the segmental motion of the treated level.

The objective of this study is to assess the effect (if any) of posterior placement of the LP Prestige disc on the motion.

To our knowledge this is the first study to assess the relation of posterior placement on the motion.

Material and Methods: We retrospectively reviewed 186 prosthesis implanted in 130 patients who underwent an LP Prestige cervical disc replacement and decompression. The distance between the posterior edge of the lower plate of the LP Prestige disc and the posterior wall of the corresponding vertebra was measured. The measurement was performed on a digitalized lateral view x-rays. The posterior placement measurement was correlated to the range of motion of the device on the same level and also on the level above and bellow.

Results: The average age was 46.7 years (range 33–66). The mean posterior placement was 2.96 mm (range 0–6 mm). Range of motion (full flexion to full extension) of the prosthesis was 9.41 degrees (range 0.2–22). Average followup was 2.3 years.

Statistical analysis showed no statistical significant correlation between the posterior placement of the disc and the motion of disc (flexion to extension, flexion to neural and neutral to extension). The p value was 0.259, 0.379 and 0.623 respectively. There was no correlation between the placement of the disc and the motion of the level above and bellow the operated level.

Conclusion: We conclude from our study that there is no correlation between the posterior placement of the Prestige LP and the segmental motion of the prosthesis and the level above and bellow.