Abstract
STUDY DESIGN: Retrospective. OBJECTIVE: To compare long term clinical outcomes of single-level versus multilevel decompression using unilateral biportal endoscopic (UBE) decompression for degenerative lumbar spinal stenosis without instability. SUMMARY OF BACKGROUND DATA: Unilateral biportal endoscopic decompression has been shown to be effective in alleviating spinal stenosis without instability. Long-term data are lacking, and, in particular, a comparison between single-level and multilevel surgery using this minimally invasive technique has not been presented. METHODS: Ninety-eight patients in each group were propensity matched based on demographics. All patients had at least 5-year follow-up. Clinical outcomes, including Oswestry Disability Index, visual analog system (VAS), time to ambulation, surgical time, and length of hospital stay, were investigated. RESULT: Oswestry Disability Index improved from 62.98 ± 11.53 before surgery to 18.51 ± 8.63 at the final follow-up in single-level decompression (P < 0.001). Multilevel decompression demonstrated improvement from 64.66 ± 13.71 to 19.31 ± 9.42 (P < 0.001). Similarly, leg and back VAS decreased from 7.39 ± 0.91 and 6.11 ± 1.21 before surgery to 1.72 ± 0.548 and 1.82 ± 0.67 at the last follow-up (P < 0.001) for single-level decompression. In comparison, for the multilevel, leg and back VAS improved from 7.47 ± 1.09 and 6.29 ± 1.28 to 1.86 ± 0.58 and 1.91 ± 0.75 (P < 0.001). No difference was observed between the groups at any time point. Complications and revision rates did not differ. Time to ambulation and length stay was markedly longer in multilevel. CONCLUSION: Outcomes, complication, and revision rates do not differ between single level and multilevel. UBE decompression can be applied to multiple levels without compromising outcomes if multiple-level decompression is deemed necessary.