Inside-Out Approach of Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression: A Detailed Technical Description, Rationale and Outcomes

Efficacy of PE-PLIF with a novel ULBD approach for lumbar degeneration diseases: a large-channel endoscopic retrospective study

PURPOSE

This study aims to assess the effectiveness of Percutaneous Endoscopic Posterior Lumbar Interbody Fusion (PE-PLIF) combined with a novel Unilateral Laminotomy for Bilateral Decompression (ULBD) approach using a large-channel endoscope in treating Lumbar Degenerative Diseases (LDD).

METHODS

This retrospective analysis evaluates 41 LDD patients treated with PE-PLIF and ULBD from January 2021 to June 2023. A novel ULBD approach, called 'Non-touch Over-Top' technique, was utilized in this study. We compared preoperative and postoperative metrics such as demographic data, Visual Analogue Scale (VAS) for pain, Oswestry Disability Index (ODI), Japanese Orthopedic Association (JOA) score, surgical details, and radiographic changes.

RESULTS

The average follow-up duration was 14.41 ± 2.86 months. Notable improvements were observed postoperatively in VAS scores for back and leg pain (from 5.56 ± 0.20 and 6.95 ± 0.24 to 0.20 ± 0.06 and 0.12 ± 0.05), ODI (from 58.68 ± 0.80% to 8.10 ± 0.49%), and JOA scores (from 9.37 ± 0.37 to 25.07 ± 0.38). Radiographic measurements showed significant improvements in lumbar and segmental lordosis angles, disc height, and spinal canal area. A high fusion rate (97.56% at 6 months, 100% at 12 months) and a low cage subsidence rate (2.44%) were noted.

CONCLUSIONS

PE-PLIF combined with the novel ULBD technique via a large-channel endoscope offers significant short-term benefits for LDD management. The procedure effectively expands spinal canal volume, decompresses nerve structures, improves lumbar alignment, and stabilizes the spine. Notably, it improves patients' quality of life and minimizes complications, highlighting its potential as a promising LDD treatment option.

Lumbar Endoscopic Unilateral Laminotomy With Bilateral Decompression Surgery in Severe Lumbar Stenosis Under Electrophysiological Monitoring-Focused on Full-Visualized Trephine/Osteotome

OBJECTIVE

Although endoscopic drill has the advantages in manipulation and hemostasis, whose low efficiency and blurred vision reduce the efficacy of lumbar endoscopic unilateral laminotomy with bilateral decompression (LE-ULBD). The present study was designed to evaluate the safety and efficacy of full-visualized trephine/osteotome in the LE-ULBD surgery for severe lumbar stenosis.

METHODS

Fifty-seven severe lumbar stenosis patients who underwent LE-ULBD between January 2020 to January 2023 were enrolled, who were divided into drill and visualized trephine groups. The medical records including demographics, operative duration, intraoperative electrophysiological findings, postoperative hospital stay or hospital stay, postoperative outcomes and complications were retrospectively reviewed and analyzed.

RESULTS

A total of 57 patients included 15 in drill and 42 in trephine group were enrolled in the study. There was significant difference in the pre- and postoperative visual analogue scale and Oswestry Disability Index scores in both groups (p < 0.05). The mean operative duration in the trephine group (101.05 ± 12.18 minutes) was shorter than that in the drill group (134.67 ± 9.68 minutes) (p < 0.05). There was no statistical difference between the 2 groups in electrophysiological monitoring, posthospital stays, postoperative outcomes and complications. Abnormal free-electromyography (EMG) were recorded in 2 (13.3%) and 5 patients (11.9%) in the drill and trephine group. Intraoperative somatosensory evoked potential changes occurred in 3 (20%) and 3 patients (7.1%) in the drill and trephine group and all patients recovered immediately when surgery ended. No serious complications and recurrence occurred in all the patients.

CONCLUSION

Full-visualized trephine/osteotome has been approved to be convenient, safe and efficient in our study, which combined with translaminar inside-out technique and EMG monitoring especially free-EMG may offer a new choice in LE-ULBD surgery for lumbar stenosis patients.

Complications and Management of Endoscopic Spinal Surgery

In the past, the use of endoscopic spine surgery was limited to intervertebral discectomy; however, it has recently become possible to treat various spinal degenerative diseases, such as spinal stenosis and foraminal stenosis, and the treatment range has also expanded from the lumbar spine to the cervical and thoracic regions. However, as endoscopic spine surgery develops and its indications widen, more diverse and advanced surgical techniques are being introduced, and the complications of endoscopic spine surgery are also increasing accordingly. We searched the PubMed/MEDLINE databases to identify articles on endoscopic spinal surgery, and key words were set as “endoscopic spinal surgery,” “endoscopic cervical foramoinotomy,” “PECD,” “percutaneous transforaminal discectomy,” “percutaneous endoscopic interlaminar discectomy,” “PELD,” “PETD,” “PEID,” “YESS” and “TESSYS.” We analyzed the evidence level and classified the prescribed complications according to the literature. Endoscopic lumbar surgery was divided into full endoscopic interlaminar and transforaminal approaches and a unilateral biportal approach. We performed a comprehensive review of available literature on complications of endoscopic spinal surgery. This study particularly focused on the prevention of complications. Regardless of the surgical methods, the most common complications related to endoscopic spinal surgery include dural tears and perioperative hematoma. transient dysesthesia, nerve root injury and recurrence. However, Endoscopic spinal surgery, including full endoscopic transforaminal and interlaminar and unilateral biportal approaches, is a safe and effective a treatment for lumbar as well as cervical and thoracic spinal diseases such as disc herniation, lumbar spinal stenosis, foraminal stenosis and recurrent disc herniation.

Comparison of the Clinical and Radiological Outcomes of Full-Endoscopic Laminotomy and Conventional Subtotal Laminectomy for Lumbar Spinal Stenosis: A Randomized Controlled Trial

STUDY DESIGN

Randomized controlled trial.

OBJECTIVE

The primary objective of this study was to compare the short-term clinical and radiological outcomes of full-endoscopic lumbar laminotomy (FEL) with those of subtotal lumbar laminectomy (STL) for lumbar spinal stenosis (LSS).

METHODS

In this prospective randomized trial a total of 52 patients were enrolled from May 2016 to September 2021 after providing written informed consent. The authors investigated 45 patients who were followed up for more than 6 months.

RESULTS

There were significant improvements in visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores after the operation in both groups. The FEL group tended to have significantly shorter hospital stay. Interestingly, a statistically significant increase in postoperative lumbar lordosis and segmental angle was observed in the FEL group and both groups, respectively. Spondylolisthesis was exacerbated or newly developed in five of the 21 patients (24%) in the STL group. In contrast, improvement in spondylolisthesis was observed in two of the 24 patients (8%) in the FEL group. There were no complications that resulted in fatal sequelae and no significant difference in the complication rate.

CONCLUSIONS

The clinical results of FEL were similar to those of STL. In addition, the results of FEL were superior to those of STL in terms of a decrease in the postoperative length of stay and radiologic instability, such as iatrogenic spondylolisthesis. The results of this study indicate that FEL is a comparable surgical method to STL for LSS.

Remodeling of Epidural Fluid Hematoma after Uniportal Lumbar Endoscopic Unilateral Laminotomy with Bilateral Decompression: Comparative Clinical and Radiological Outcomes with a Minimum Follow-up of 2 Years

STUDY DESIGN

Retrospective cohort study.

PURPOSE

To evaluate the clinical and radiological effects of epidural fluid hematoma in the medium term after lumbar endoscopic decompression.

OVERVIEW OF LITERATURE

There is limited literature comparing the effect of postoperative epidural fluid hematoma after uniportal endoscopic decompression.

METHODS

Magnetic resonance imaging (MRI) and clinical evaluation were performed for patients with single-level uniportal endoscopic lumbar decompression with a minimum follow-up of 2 years.

RESULTS

A total of 126 patients were recruited with a minimum follow-up of 26 months. The incidence of epidural fluid hematoma was 27%. Postoperative MRI revealed a significant improvement in the postoperative dura sac area at postoperative day 1 and at the upper endplate at 6 months in the hematoma cohort (39.69±15.72 and 26.89±16.58 mm2) as compared with the nonhematoma cohort (48.92±21.36 and 35.1±20.44 mm2), respectively (p <0.05); and at the lower endplate on postoperative 1 day in the hematoma cohort (51.18±24.69 mm2) compared to the nonhematoma cohort (63.91±27.92 mm2) (p <0.05). No significant difference was observed in the dura sac area at postoperative 1 year in both cohorts. The hematoma cohort had statistically significant higher postoperative 1-week Visual Analog Scale (VAS; 3.32±0.68) pain and Oswestry Disability Index (ODI; 32.65±5.56) scores than the nonhematoma cohort (2.99±0.50 and 30.02±4.84, respectively; p <0.05). No significant difference was found at the final follow-up VAS, ODI, and MRI dura sac area.

CONCLUSIONS

Epidural fluid hematoma is a common early postoperative MRI finding in lumbar endoscopic unilateral laminotomy with bilateral decompression. Conservative management is the preferred treatment option for patients who do not have a neurological deficit. Symptoms last only a few days and are self-limiting. A common endpoint is a remodeled fluid hematoma and the subsequent expansion of the dura sac area.

Learning Curve and Complications of Unilateral Biportal Endoscopy: Cumulative Sum and Risk-Adjusted Cumulative Sum Analysis

OBJECTIVE

The purpose of this study was to investigate the learning curve and complications of unilateral biportal endoscopy (UBE) in the treatment of lumbar disc herniation (LDH) and lumbar spinal stenosis (LSS).

METHODS

This was a retrospective cohort analysis of 197 consecutive patients who received UBE unilateral laminotomy bilateral decompression (UBE-ULBD) or lumbar discectomy (UBE-LD) surgery, including 107 males and 90 females with an average age of 64.83 ± 14.29 years. Cumulative sum (CUSUM) and risk-adjusted cumulative sum analysis (RA-CUSUM) were used to evaluate the learning curve, with the occurrence of complications defined as surgical failure, and variables of different phase of the learning curve were compared.

RESULTS

The cutoff point of learning curve of UBE surgery was 54 cases according to CUSUM analysis. The learning curve of UBE-ULBD and UBE-LD were divided into 3 phases. The first cutoff points were 31 and 12 cases, and the second cutoff point were 67 and 32 cases respectively. With the progress of the learning curve, the operation time and postoperative hospital stays decreased. The visual analogue scale and Oswestry Disability Index at the last follow-up were significantly lower than that before surgery. The incidence of surgical failure was 6.11% and began to decrease after the 89th case based on RA-CUSUM analysis. The surgical failure rate decreased from 10.11% to 2.78 after the 89th case with significant different.

CONCLUSION

UBE surgery is effective in the treatment of LDH and LSS with low incidence of complications. But a learning curve of at least 54 cases still required for mastering UBE surgery.

Full Endoscopic Surgery for Thoracic Pathology: Next Step after Mastering Lumbar and Cervical Endoscopic Spine Surgery?

Thoracic disc herniation and stenosis are relatively rare, and various symptoms make them difficult to diagnose. Due to the complexity of neural and vascular structure, surgical treatment of thoracic pathology is challenging. Endoscopic spine surgery is an emerging minimally invasive surgical option. Based on wide experience on the cervical and lumbar spine, an endoscopic approach for the thoracic pathology can be performed beyond the learning curve. Transforaminal approach for thoracic disc herniation, endoscopic unilateral approach, and bilateral decompression for thoracic stenosis have been reported as favorable and safe surgical options. In the present study, the authors described the detailed surgical procedure as well as tips and tricks.

Remodeling Pattern of Spinal Canal after Full Endoscopic Uniportal Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression: One Year Repetitive MRI and Clinical Follow-Up Evaluation

Objective: There is limited literature on repetitive postoperative MRI and clinical evaluation after Uniportal Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression. Methods: Clinical visual analog scale, Oswestry Disability Index, McNab’s criteria evaluation and MRI evaluation of the axial cut spinal canal area of the upper end plate, mid disc and lower end plate were performed for patients who underwent single-level Uniportal Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression. From the evaluation of the axial cut MRI, four types of patterns of remodeling were identified: type A: continuous expanded spinal canal, type B: restenosis with delayed expansion, type C: progressive expansion and type D: restenosis. Result: A total of 126 patients with single-level Uniportal Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression were recruited with a minimum follow-up of 26 months. Thirty-six type A, fifty type B, thirty type C and ten type D patterns of spinal canal remodeling were observed. All four types of patterns of remodeling had statistically significant improvement in VAS at final follow-up compared to the preoperative state with type A (5.59 ± 1.58), B (5.58 ± 1.71), C (5.58 ± 1.71) and D (5.27 ± 1.68), p < 0.05. ODI was significantly improved at final follow-up with type A (49.19 ± 10.51), B (50.00 ± 11.29), C (45.60 ± 10.58) and D (45.60 ± 10.58), p < 0.05. A significant MRI axial cut increment of the spinal canal area was found at the upper endplate at postoperative day one and one year with type A (39.16 ± 22.73; 28.00 ± 42.57) mm2, B (47.42 ± 18.77; 42.38 ± 19.29) mm2, C (51.45 ± 18.16; 49.49 ± 18.41) mm2 and D (49.10 ± 23.05; 38.18 ± 18.94) mm2, respectively, p < 0.05. Similar significant increment was found at the mid-disc at postoperative day one, 6 months and one year with type A (55.16 ± 27.51; 37.23 ± 25.88; 44.86 ± 25.73) mm2, B (72.83 ± 23.87; 49.79 ± 21.93; 62.94 ± 24.43) mm2, C (66.85 ± 34.48; 54.92 ± 30.70; 64.33 ± 31.82) mm2 and D (71.65 ± 16.87; 41.55 ± 12.92; 49.83 ± 13.31) mm2 and the lower endplate at postoperative day one and one year with type A (49.89 ± 34.50; 41.04 ± 28.56) mm2, B (63.63 ± 23.70; 54.72 ± 24.29) mm2, C (58.50 ± 24.27; 55.32 ± 22.49) mm2 and D (81.43 ± 16.81; 58.40 ± 18.05) mm2 at postoperative day one and one year, respectively, p < 0.05. Conclusions: After full endoscopic lumbar decompression, despite achieving sufficient decompression immediately postoperatively, varying severity of asymptomatic restenosis was found in postoperative six months MRI without clinical significance. Further remodeling with a varying degree of increment of the spinal canal area occurs at postoperative one year with overall good clinical outcomes.