Unilateral Biportal Endoscopic Approach for Symptomatic Adjacent Segment Disease: Case Report and Technical Note.

Introduction: Recently, lumbar degenerative disease has been treated using unilateral biportal endoscopic (UBE) lumbar interbody fusion. However, the use of the UBE approach for symptomatic ASD following lumbar interbody fusion surgery isn't illustrated widely in the literature. This case report and technical note describe the use of the UBE approach for symptomatic ASD. Case Report: A 72-year-old female who underwent conventional fusion surgery elsewhere twelve years ago at the L5-S1 level presented with severe back pain (VAS 8/10) and radicular pain in both legs (left > right) (left VAS 7/10, right VAS 7/10) for 1 year with an ODI score of 70%. Preoperative X-ray and MRI showed dynamic instability with spondylolisthesis at L4-5. We performed an upper-level extension using UBE FES techniques to resolve ASD. The operative time was 132 minutes, blood loss was 40 ml. After surgery, the patient was followed up at 1 week, 6 weeks, 3 months, 6 months, 12 months, and 2 years. The pain and tingling sensation in the legs got better at the 1-week follow-up itself with a VAS score of 0/10 and an ODI score of 10% at the 2-year follow-up. Patient satisfaction was surveyed using Odom's criteria at each follow-up visit (at 1 week, 6 weeks,3 months, 6 months, and 2 years) and found to be excellent. Postoperative imaging showed a good reduction and canal decompression at L4-5. Conclusion: The UBE fusion extension technique for ASD is a safe, less invasive, and effective treatment option for lumbar interbody fusion extension and posterior pedicle screw revision with less morbidity and early recovery.