Early Clinical and Radiologic Evaluation of Unilateral Biportal Endoscopic Unilateral Laminotomy and Bilateral Decompression in Degenerative Lumbar Spinal Stenosis: A Retrospective Study.

Background:  The aim of this study is to evaluate the changes in radiologic parameters and clinical outcomes following unilateral biportal endoscopic unilateral laminotomy and bilateral decompression (UBE ULBD) for treatment of central lumbar spinal stenosis.

Methods:  Forty-one central lumbar spinal stenosis patients who underwent UBE ULBD were enrolled from April 2021 to February 2023. Visual analog scale (VAS) for back pain and leg pain, Oswestry Disability Index (ODI) score, and the modified MacNab criteria were assessed preoperatively and postoperatively. The preoperative and postoperative cross-sectional area of the spinal canal (CSAC), anteroposterior diameter, horizontal width, and ipsilateral and contralateral lateral recess height were calculated from axial computed tomography (CT) scans. Percentage of facet joint preservation measured on axial CT scans was obtained preoperation and postoperation.

Results:  The VAS for back and leg pain improved from 7.24 ± 0.80 and 7.59 ± 0.59 preoperatively to 2.41 ± 0.55 and 2.37 ± 0.62 (p < 0.05) postoperatively and 1.37 ± 0.54 and 1.51 ± 0.55 at the last follow-up (p < 0.05). For ODI, improvement from 60.37 ± 4.44 preoperatively to 18.90 ± 4.66 (p < 0.05) at the last follow-up was observed. CT scans demonstrated that the postoperative CSAC increased significantly from 287.84 ± 87.81 to 232.97 ± 88.42 mm (p < 0.05). The mean postoperative anteroposterior diameter and horizontal width increased significantly from 18.01 ± 3.13 and 19.57 ± 3.80 to 22.19 ± 4.56 and 21.04 ± 3.72 mm, respectively (p < 0.05). The ipsilateral lateral recess height and contralateral lateral recess height were 3.39 ± 1.12 and 3.20 ± 1.14 mm preoperatively and 4.03 ± 1.37 and 3.83 ± 1.32 mm (p < 0.05) postoperatively, with significant differences. The ipsilateral and contralateral facet joint preservations were 88.17 and 93.18%, respectively.

Conclusion:  The UBE ULBD surgery is a safe and effective treatment for central lumbar spinal stenosis, associated with significant improvement in clinical outcomes and radiologic parameters. Studies with larger samples and longer follow-up periods are needed for further research.