Comparing the 5-Year Health State Utility Value of Cervical Disc Replacement and Anterior Cervical Discectomy and Fusion.

STUDY DESIGN

Health utility analysis.

OBJECTIVES

To determine the health state utility (HSU) of 1- and 2-level anterior cervical discectomy and fusion (ACDF) and cervical disc replacement (CDR).

METHODS

Data from the Medtronic Prestige Cervical Disc investigational device exemption studies was used. Four groups were defined: 1-level ACDF, 1-level CDR, 2-level ACDF, and 2-level CDR. The 36-item Short Form Health Survey (SF-36) was collected at baseline, 12 months, 24 months, 36 months, and 60 months postoperatively and converted into utility scores for each time point. A repeated-measures 1-way analysis of variance (ANOVA) was used to detect differences among groups. Tukey's method for multiple comparisons was used to determine which means within the groups were statistically different ( < .05).

RESULTS

We found a statistically significant difference in HSU among groups as determined by repeated-measures 1-way ANOVA ( = .0008). Post hoc analysis indicated that 1-level ACDF had a statistically lower utility score compared with 1- and 2-level CDR ( = .04 and = .02, respectively). Similarly, 2-level ACDF had lower utility values compared with 2-level CDR ( = .010). One-level ACDF utility values were not different from 2-level ACDF values ( = .55). Similarly, 1-level CDR and 2-level CDR did not have different utility values ( = .67).

CONCLUSIONS

Overall, CDR had higher health state utility scores for 1- and 2-level procedures at every time point. This study indicates that CDR results in a higher postoperative health utility state than ACDF, and may therefore be an effective alternative to ACDF for treating degenerative conditions of the cervical spine.