Abstract:[Objective] To compare the clinical efficacy of unilateral biportal endoscopy (UBE) and open bilateral paravertebral intermuscular (IM) approaches for discectomy and lumbar interbody fusion in the treatment of lumbar disc herniation in middle-aged and elderly. [Methods] From January 2019 to December 2021, 67 patients who were undergoing surgical treatments for lumbar disc herniation in our hospital were included in this study, and were divided into two groups according to random number table method. The patients in the UBE group had operation conducted under UBE, while those in the IM group got discectomy and interbody fusion through the open bilateral paravertebral intermuscular approaches. The perioperative period, follow-up and imaging documents of the two groups were compared. [Results] The UBE group proved significantly less than the IM group in terms of incision length [(5.4±0.5) cm vs (7.4±0.9) cm, P＜0.001], intraoperative blood loss [(128.7±10.4) ml vs (209.6±15.4) ml, P＜0.001], time to regain walking [(3.2±0.6) days vs (5.8±1.5) days, P＜0.001] and hospitalization time [(9.6±1.3) days vs (11.4±1.5) days, P＜0.001], but the former was significantly greater than the latter in terms of operative time [(153.2±12.7) min vs (135.5±10.6) min, P＜0.001] and the number of intraoperative fluoroscopy [(5.8±1.4) times vs (4.5±0.8) times, P＜0.001]. In addition, the incidence of dural tear in UBE group was significantly higher than that in the IM group (20.6% vs 3.0%, P=0.026). With time of follow-up lasted for (15.2±1.0) months, the VAS and ODI scores in both groups were significantly reduced (P＜0.05). The UBE group was significantly superior to the IM group regrading VAS score [(2.7±0.6) vs (3.0±0.5), P=0.029] and ODI score [(30.5±4.6) vs (33.6±5.2), P= 0.012] a month after surgery, as well as ODI score 3 months after operation [(21.5±3.7) vs (24.1±4.7), P=0.014]. With respect of imaging, the dural sac area, lumbar intervertebral space height, and lumbar lordotic angle significantly increased postoperatively compared with those preoperatively (P＜0.05), while Lenke grade for fusion significantly improved over time in both groups (P＜0.05). However, there were no statistically significant differences in the above image indicators between the two groups at any corresponding time points (P＞0.05). [Conclusion] The UBE discectomy and fusion for lumbar disc herniation in the middle-aged and elderly can shorten hospital stay and reduce blood loss, which is conducive to the recovery of patients.