Full-endoscopic transpedicular discectomy (FETD) for lumbar herniations: Case report and review of the literature

Full Endoscopic Transpedicular Discectomy for a Rostrally Migrated L5-S1 Disc Herniation in the Setting of Previous Lumbar Surgery: A Case Report With Intraoperative Video

BACKGROUND AND IMPORTANCE

The surgical management of rostral disc herniations at L5-S1 poses challenges for conventional endoscopic approaches, particularly in patients who have had previous lumbar surgery. We present a full endoscopic transpedicular discectomy (FETD), whereby a pediculotomy is created to pass an endoscope through the pedicle for intracanal access. This addresses anatomic obstacles and potential complications associated with other endoscopic and minimally invasive or open techniques. To date, this is the only article to highlight this approach with a case report and intraoperative video.

CLINICAL PRESENTATION

A 76-year-old man with a history of L3-S1 laminectomy presented with left leg pain and a near-complete left foot drop. An MRI revealed a left paracentral rostrally migrated disc herniation arising from L5-S1 with impingement of the exiting left L5 nerve root at the inferomedial aspect of the pedicle of L5. The patient consented to the FETD procedure. Using sequential reamers of increasing diameter and a high-speed burr, a superolateral to inferomedial pediculotomy was performed. This approach allowed us to target the pathology at the point of maximum compression without traversing the prior operative field. A transforaminal endoscopic approach was not possible with the iliac crest obstructing rostral angulation. The disc was successfully removed without any intraoperative complications, and after surgery, the patient's radiculopathy resolved without any radiographic evidence of instability.

CONCLUSION

FETD is a unique approach that demonstrates the versatility of endoscopic spine surgery, offering advantages over conventional approaches particularly for rostral disc herniations at L5-S1 in the setting of prior lumbar surgery.

The Biomechanics of the Transpedicular Endoscopic Approach

STUDY DESIGN

Biomechanical cadaveric study.

OBJECTIVE

The goal of this study was to analyze the effects of an endoscopic transpedicular approach with different drill diameters (6 and 8 mm) and compare them with the intact native side. In addition, the influence of bone quality on the resistance of the pedicle was investigated.

SUMMARY OF BACKGROUND DATA

Clinical studies have repeatedly highlighted the benefits of endoscopic transpedicular decompression for downmigrated lumbar disc herniations. However, the biomechanical effects on pedicle stability have not been studied up to now.

MATERIALS AND METHODS

Twenty-four vertebras originating from four fresh-frozen cadavers were tested under uniaxial compression load in a ramp-to-failure test: (1) the tunneled pedicle on one side, and (2) the native pedicle on the other side. Twelve lumbar vertebrae were assigned to drill diameter of 6 mm and the other 12 to diameter of 8 mm.

RESULTS

The median ratio of sustained force for the operated side compared with the intact contralateral side is equal to 74% (63-88) for both drill diameters combined. An 8 mm transpedicular approach recorded an axial resistance of 77% (60-88) compared with the intact contralateral side ( P =0.002). A 6 mm approach resulted in an axial resistance of 72% (66-84) compared with the intact opposite side ( P =0.01). No significant difference between the two different drill diameters was recorded ( P =1). For all three subgroups (intact, 8 mm, 6 mm) the Hounsfield units-values and the absolute resistance force showed significant correlations (intact: ρ=0.859; P <0.001; 8 mm: ρ=0.902; P <0.001; 6 mm: ρ=0.835; P <0.001).

CONCLUSION

The transpedicular approach significantly reduces the axial resistance force of the pedicle, which may lead to pedicle fracture. Bone quality correlated positively with the absolute resistance force of the pedicle, whereas the influence of the drill hole diameter plays only a limited role.

Percutaneous Endoscopic Suprapedicular Decompression in the Treatment of Down-Migrated Lumbar DiscHerniation

OBJECTIVE

This study aimed to investigate the clinical efficacy of percutaneous endoscopic suprapedicular decompression in treatment of down-migrated lumbar disc herniation.

METHODS

The clinical data of 43 patients with down-migrated lumbar disc herniation treated with endoscopic surgery at our hospital between January 2022 and January 2023 were retrospectively analyzed. Twenty-two and 21 patients underwent percutaneous endoscopic decompression using the suprapedicular and transforaminal endoscopic surgical system approaches, respectively. The perioperative, follow-up, and imaging data of the groups were compared.

RESULTS

Surgery was uneventful in both groups. The number of intraoperative fluoroscopies and duration of surgery were significantly lower in the suprapedicular group (P < 0.05). The patients in both groups were followed up for at least 12 months. At the last follow-up, lumbar pain and leg pain visual analog scale, Oswestry Disability Index, and 36-Item Short Form Health Survey scores were significantly improved in both groups compared with preoperative values (P < 0.05); the differences in these indexes between the 2 groups were not significant preoperatively (P > 0.05). However, at the last postoperative follow-up, lumbar pain visual analog scale scores were significantly better in the suprapedicular group (0.83 ± 0.85 vs. 2.54 ± 1.32, P < 0.05). There was no significant change in intervertebral space height or lumbar lordotic angle compared with preoperative values in either group at the last follow-up (P > 0.05). However, the spinal canal cross-sectional area significantly increased (P < 0.05).

CONCLUSIONS

The treatment of down-migrated lumbar disc herniation via a suprapedicular approach enabled the incision of the superior margin of the pedicle as needed under direct vision, involved less fluoroscopy while preserving facet joint stability, and enabled targeted removal of the herniated nucleus pulposus, thus greatly reducing residual nucleus pulposus. This surgical procedure was safe, rapid, and showed satisfactory therapeutic efficacy.

Full Endoscopic Transpedicular Technique in the Treatment of High Grade Down Migrated Herniated Disc: An Evaluation of Clinical Outcomes at 12 Months Follow-Up

OBJECTIVE

High-grade migrated lumbar disc herniation (LDH) such as up-migrated and down-migrated discs are challenging pathologies to treat. High-grade migrated discs are usually sequestered and situated adjacent to the medial pedicle wall. This can be easily addressed if the pedicle is used as an access route. The authors present a retrospective case series of high-grade migrated LDH treated using a full endoscopic transforaminal approach.

MATERIALS AND METHODS

This is a retrospective case series. The clinical outcomes in the patients were evaluated according to improvement in the symptoms as suggested by improvement in Visual Analog Score (VAS) and Oswestry Disability Index (ODI) scores in the immediate postoperative period and at the final follow-up. The radiological outcomes were evaluated using postoperative magnetic resonance imaging and computed tomography scans. After the data were collected and tabulated, descriptive statistics were used for continuous variables. The t test was used to determine the significance of changes in the VAS and ODI scores. Statistical significance was set at P < 0.05.

RESULTS

Five patients underwent discectomy using the transpedicular technique, and the mean preoperative VAS scores for the back and leg were 7.2 ± 0.83 and 8.4 ± 0.54, respectively. The mean VAS scores at the final follow-up for the back was 0.2 ± 0.4 and 0 for the leg (P < 0.05). The mean preoperative ODI score was 72 ± 8.3, which improved to 6 ± 4.69 at the final follow-up (P < 0.05). All patients had a hospital stay of 1 day.

CONCLUSIONS

The full endoscopic transpedicular approach is a good option for treating highly migrated LDH. Surgical planning, including pedicle morphometry and the angle of the approach, should be undertaken preoperatively for the best results.

A Novel Trajectory for a Transpedicular Approach in the Treatment of a Highly Downward-Migrated Lumbar Herniation with a Full Endoscopic Technique

Background

To evaluate the clinical outcome of full endoscopic discectomy using a novel trajectory via a transpedicular approach.

Method

Thirty-five patients were enrolled in this retrospective study between July 2014 and October 2019 in the Beijing Haidian Hospital. All patients were treated with full-endoscopic lumbar discectomy via a transpedicular approach with an oblique trajectory. The imaging parameters, including pedicle height and angle of trajectory, were recorded. The preoperative and postoperative clinical data were collected for statistical analysis.

Results

All patients underwent successful surgery without severe complications. We compared the visual analogue scale and Oswestry disability index scores before and after surgery. The differences were statistically significant (p < 0.05). According to the modified Macnab criteria, the good-to-excellent rate was 85.7% at the last follow-up. The average angles of trajectory in the sagittal and coronal planes were 34.5° ± 2.9° and 47.1° ± 5.0°, respectively.

Conclusion

The new trajectory of the transpedicular approach with a full endoscopic technique for an extremely downward-migrated disc herniation showed excellent results in a small sample study. A precise surgical plan is required, comprising measurements of the pedicle height and angle of the bone tunnel.

Foraminoplasty at the Base of the Superior Articular Process with Bone Drilling for Far-Downward Discs in Percutaneous Endoscopic Lumbar Discectomy: A Retrospective Study

Purpose

Percutaneous endoscopic lumbar discectomy (PELD) is usually used to treat lumbar disc herniation (LDH). This study aims to describe PELD by foraminoplasty in the treatment of far-downward migrated LDH and to demonstrate the clinical efficacy by a retrospective evaluation.

Patients and Methods

Between January 2017 and July 2018, 41 patients with far-downward migrated LDH were treated with PELD by foraminoplasty at the base of the superior articular process (SAP). Clinical efficacy was evaluated with a visual analogue scale (VAS) score, the Oswestry disability index (ODI), and the modified Macnab criteria. Postoperative follow-up data (1 month, 6 months, 18 months) were recorded.

Results

The surgical levels included L2/3 (1 patient), L3/4 (1 patient), L4/5 (17 patients), and L5/S1 (22 patients). The VAS and ODI scores indicated a significant improvement 18 months after surgery (mean ± standard deviation, VAS, 6.9±1.3 versus 0.5±0.8; ODI, 66.3±12.2 versus 14.0±8.2, respectively). Based on the modified Macnab criteria, 92.7% of patients had a good-to-excellent rate. There were three patients with a dural tear, and one patient had recurrent disc herniation.

Conclusion

PELD by foraminoplasty at the base of the superior articular process is a good method for treating far-downward migrated LDH.

A novel vertebral trench technique (VTT) involving transforaminal endoscopic lumbar foraminotomy (TELF) for very highly up-migrated lumbar disc herniation above L5

BACKGROUND

Percutaneous endoscopic lumbar discectomy (PELD) has become popular for the treatment of symptomatic lumbar disc herniation (LDH). The very highly up-migrated lumbar disc herniation (VHUM-LDH) is difficult to remove under PELD. The purpose of this research is to investigate the feasibility, clinical efficacy and operative nuances of a novel VTT involving TELF for this type of herniation.

METHODS

Eleven patients with very highly up-migrated LDH who underwent VTT involving TELF discectomy from May 2016 to May 2019 were included in this study. The operative time, length of hospital stay, and postoperative complications were recorded. Pre-and postoperative radiologic findings were investigated. All the patients were followed more than 1 year. The visual analogue score (VAS), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) scores and modified MacNab criteria were used to assess surgical efficacy.

RESULTS

All the 11 patients underwent successful surgery. We compared the VAS, ODI, and JOA scores before and after surgery. The differences were statistically significant (P < 0.05). According to the modified MacNab criteria, 10 patients were assessed as "excellent", 1 patient was assessed as "good" at the last follow up.

CONCLUSION

The novel VTT involving TELF discectomy is a supplement to the traditional PELD. This technique enables the endoscope with working cannula to get closer the sequestrated nucleus pulposus without irritating the exiting nerve root, and facilitates the nucleus pulposus be removed successfully under direct visualization. The VTT involving TELF discectomy can be a safe, effective and feasible surgical procedure for the treatment of LDH with very highly up-migrated.