ObjectiveTo investigate the difference between four transforaminal endoscopic approaches in the treatment of serious lumbar disc herniation.MethodsBetween October 2010 and February 2015, a total of 122 patients with serious lumbar disc herniation were enrolled and treated with discectomy under transforaminal endoscope. The patients were divided into 4 groups according to the different approaches. The transforaminal endoscopic spine system (TESSYS) technology was used in group A (31 cases), Yeung endoscopic spine system (YESS) technology was used in group B (30 cases), improved transforaminal endoscopic access (ITEA) technology was used in group C (31 cases), and interlaminar dorsal access (IDA) technology was used in group D (30 cases). There was no significant difference in gender, age, disease duration, lesion segment, and preoperative visual analogue scale (VAS) score of low back pain, VAS score of bilateral lower extremities pain, Oswestry disability index (ODI), intervertebral height, lumbar curvature index (LCI), and disc degeneration grading between groups (P>0.05). The removal volume of nucleus pulposus was compared; after operation, VAS score, ODI score, LCI, intervertebral height, and disc degeneration grading were used to evaluate the effectiveness.ResultsThe removal volumes of nucleus pulposus in groups A, B, C, and D were (3.6±0.9), (3.5±0.7), (4.6±1.0), (3.1±1.1) cm3, respectively. There were significant differences between groups (P<0.05). All incisions healed by first intention, and no early postoperative complications was found. All cases were followed up 12-35 months, with an average of 24 months. During follow-up, there was no recurrence of nucleus pulposus herniation, infection of intervertebral space, cerebrospinal fluid leakage, epidural hematoma, or other complications. At last follow-up, the VAS scores of low back pain and bilateral lower extremities pain, and ODI scores in each group significantly improved when compared with those before operation (P<0.05); there was no significant difference in the scores and improvements between groups after operation (P>0.05). At last follow-up, the disc degeneration grading in group B significantly improved when compared with that before operation (P<0.05); there was no significant difference between groups (P>0.05). At last follow-up, there was no significant difference in LCI of each group when compared with that before operation (P>0.05); and there was no significant difference in LCI and loss value between groups (P>0.05). There was no significant difference in the intervertebral height of the 4 groups at immediate after operation and last follow-up when compared with preoperative value (P>0.05), and there was no significant difference between groups at immediate after operation and last follow-up (P>0.05).ConclusionApplication of transforaminal endoscope in the treatment of serious lumbar disc herniation has great clinical outcomes. The ITEA technology can obtain a wider field of view and be more convenient to find and remove the degenerative nucleus pulposus. However, the appropriate approach should be selected according to the symptoms and characteristics of lumbar disc herniation.