Long-Term Outcomes Following Lumbar Total Disc Replacement Using ProDisc-II: Average 10-Year Follow-Up at a Single Institute.

STUDY DESIGN A retrospective analysis. OBJECTIVE To evaluate the long-term clinical and radiographic outcomes and to investigate who achieved the successful outcomes after lumbar total disc replacement (TDR) using ProDisc II. SUMMARY OF BACKGROUND DATA There are few evidences regarding the long-term efficacy and safety of TDR. Furthermore, it has not been addressed which patients achieved good outcomes in long-term follow-up. METHODS Data at 1-, 2-, 5-, 7-year, and last follow-up were used for the analysis. According to the presence of combined pathologies, patients were categorized as groups A and B (presumed good and bad candidates, respectively). Clinical outcomes were evaluated using visual analog scale, Oswestry Disability Index, clinical success rate, and subjective satisfaction (four-point scale). Radiographic results included segmental range of motion. RESULTS Total study population was 54 patients with 69 segments with the average follow-up duration of 120.0 months. There were 39 patients in group A and 15 in group B. Visual analog scale and Oswestry Disability Index scores were improved significantly at all follow-up periods, reaching maximal improvement at the postoperative 2 years. Clinical success rate and satisfaction rate were significantly higher in group A (76.9% and 87.2%, respectively) than those in group B (40.0% and 60.0%, respectively) at the last follow-up. Five patients (9.3%) required revision fusion surgeries, and they are all in group B. The final segmental range of motion was well maintained in monosegmental TDR, but not in bisegmental TDR. CONCLUSION Lumbar TDR using Prodisc II showed the successful outcomes with the clinical success rate of 76.9% and the satisfaction rate of 87.2% when the patients were presumed as good candidate for TDR. However, the patients who had the combined pathologies showed suboptimal results with high risk of the revision surgeries. Thus, the strict patient selection process is mandatory for the successful outcomes. LEVEL OF EVIDENCE 4.