Full Endoscopic Lumbar Foraminoplasty with Periendoscopic Visualized Trephine Technique for Lumbar Disc Herniation with Migration and/or Foraminal or Lateral Recess Stenosis

Foraminoplasty Performed with a Trephine and a New Tool in Transforaminal Endoscopic Lumbar Discectomy: A Single-Center Retrospective Study

OBJECTIVE

Foraminoplasty is an important step in transforaminal endoscopic lumbar discectomy (TELD). A trephine is widely used in foraminoplasty. However, foraminoplasty using a trephine alone sometimes fails to remove the resected bone, resulting in the bone remaining in the foramen or spinal canal, which can potentially cause neurological irritation or injury. The objective of this study is to introduce a self-designed tool, referred to as an anchoring drill, for use with a trephine in foraminoplasty in TELD and to evaluate its advantages.

METHODS

A retrospective review was performed to identify patients who underwent L4-5 TELD between January 2019 to January 2022. Foraminoplasty was performed in all patients. Depending on whether the anchoring drill was used or not, patients were divided into two groups. Surgery-related parameters and complications were reviewed. Visual analog scale (VAS) and Japanese Orthopaedic Association (JOA) scores were also assessed for all patients. SPSS statistical software was used for statistical calculation.

RESULTS

A total of 100 patients were included (55 in the anchoring drill group and 45 in the trephine group). The incidence of residual bone fragments after foraminoplasty of the anchoring drill group was 9.09%, which was lower than that of the trephine group, at 33.33% (p < 0.05). The mean endoscopic operation time of the anchoring drill group was shorter than that of the trephine group (p < 0.05). The mean fluoroscopy time and duration of foraminoplasty showed no significant differences between the two cohorts. The total perioperative complication incidence was lower in the anchoring drill group, in which the neural irritation incidence showed a significant difference (anchoring drill group: 3.64%, trephine group: 17.78%, p < 0.05). VAS and JOA scores were significantly improved after the operation for all patients (p < 0.001), however, no statistical differences were found between the two groups at each follow-up visit.

CONCLUSION

The combination of a trephine with an anchor drill was demonstrated to be safe and effective in foraminoplasty in TELD, improving the success rate of foraminoplasty and reducing neurological complications compared to using trephine alone.

Comparison of bone reamer and trephine for foraminoplasty in percutaneous endoscopic lumbar discectomy based on 3D slicer and Digimizer software

OBJECTIVE

To explore the applicability of bone reamer and trephine for foraminoscopy in percutaneous endoscopic lumbar discectomy (PELD), and to provide a theoretical basis for foraminoplasty options in clinical practice.

METHODS

This study was a prospective cohort study. Sixty-three consecutive patients who underwent PELD for lumbar disc herniation between May 2021 and July 2022 were analysed. Foraminoplasty were performed by bone reamer or trephine. The amount of bone removed and the foramen area enlarged during foraminoplasty by both tools were measured by 3D slicer and Digimizer software, and the numbers of fluoroscopic views were recorded.

RESULTS

The bone reamer removed less bone in the Superior Articular Process (SAP) than the trephine (t = 17.507, P < 0.001), and the area enlarged by the bone reamer was smaller than that of the trephine (t = 10.042, P = 0.002). The overall numbers of fluoroscopic views were significantly more in the bone reamer group than in the trephine group (t = 19.003, P < 0.001). In the bone reamer group, when the area of preoperative (FPZ) was no less than 54.55 mm2, the mean number of fluoroscopic views significantly decreased (t = 14.443, P = 0.001).

CONCLUSION

Bone reamer was safer and trephine was more efficient for foraminoscopy in PELD. An area of preoperative (FPZ) of 54.55 mm2 can be used as a critical value: bone reamer reduced the risk for cases above the value, while trephine improved the efficiency for cases less than the value.

Utility of Large Diameter Visible Trephine in Percutaneous Endoscopic Lumbar Interbody Fusion: A Technical Report

PURPOSE

In this study, a large diameter visible trephine was designed and used in percutaneous endoscopic lumbar interbody fusion to increase endoscopic bone decompression efficiency. Large diameter visible trephine-related technical notes and preliminary clinical experience are described.

METHODS

A large diameter visible trephine was designed with normal diameter visible trephine as template. A total of 38 patients with lumbar degenerative diseases who underwent single-level percutaneous endoscopic lumbar interbody fusion with large or normal diameter visible trephine were included into a retrospective study. Operation time, bone decompression time, blood loss, intraoperative fluoroscopy, bone decompression fluoroscopy, and dura or nerve injury cases were recorded and analyzed statistically. Visual Analog Scale (VAS) scores and Oswestry Disability Index (ODI) were used to analyze the clinical outcomes of the 2 groups.

RESULTS

The baseline data of the 2 groups were statistically similar. There was no significant difference in postoperative VAS and ODI scores between the 2 groups. Operation time and bone decompression time of large diameter visible trephine group were significantly shorter than that of normal diameter visible trephine group (P < 0.05). Intraoperative fluoroscopy times and bone decompression fluoroscopy times of large diameter visible trephine group were significantly more than that of normal diameter visible trephine group (P < 0.05). Blood loss of the 2 groups were not statistically different. There were no dura or nerve injury cases in the 2 groups.

CONCLUSIONS

For percutaneous endoscopic lumbar interbody fusion, the large diameter visible trephine is a safe and efficient endoscopic bone decompression tool under fluoroscopic guidance.

Comparison of the efficacy of fully endoscopic spine surgery using transforaminal and interlaminar approaches in the treatment of prolapsed lumbar 4/5 disc herniation

Background

There is still much controversy about whether transforaminal or interlaminar fully endoscopic spine surgery can better treat lumbar 4/5 disc herniation. Therefore, this study intends to compare the clinical efficacy of fully endoscopic spine surgery through transforaminal and interlaminar approaches in the treatment of lumbar 4/5 disc herniation.

Methods

Seventy-six patients with lumbar 4/5 disc herniation admitted from March 2019 to June 2020 were divided into the transforaminal approach group (endoscopic transforaminal lumbar discectomy, ETLD; 54 cases) and the interlaminar approach group (endoscopic interlaminar lumbar discectomy, EILD; 22 cases) according to different surgical methods. The general clinical data and clinical evaluation scale of the patients were compared.

Results

The post-operative ODI and VAS scores were significantly better in the EILD group (P < 0.05). The VAS and ODI scores of patients with upper-shoulder and sub-axillary types in the EILD group were superior to those in the ETLD group (P < 0.05), while the VAS and ODI scores of patients with the pre-radicular type were better when they underwent ETLD rather than EILD (P < 0.05). Patients with Lee zone III type in the EILD group had better post-operative ODI scores than those in the ETLD group (P < 0.05), but there was no significant difference in VAS scores (P > 0.05). Patients with Lee zone IV type who underwent EILD had better VAS and ODI scores than those who underwent ETLD (P < 0.05).

Conclusions

For patients with a prolapsed intervertebral disc that belongs to the upper-shoulder type, sub-axillary type, or Lee III or IV type, EILD can achieve better outcomes.

Usefulness of 3D CT/MRI Fusion Imaging for the Evaluation of Lumbar Disc Herniation and Kambin's Triangle

Study design: Prospective study. Objective: The aim of this study is to visualize the morphology of a lumbar herniated disc and Kambin’s triangle in three dimensions (3D) based on preoperative CT/MRI fusion images. Methods: CT/MRI fusion images of 23 patients (10 males and 13 females; mean age 58.2 years) were used to evaluate Kambin’s triangle, which is created between the superior articular process (SAP), exiting nerve root (ENR), inferiorly by the superior endplate of the lower lumbar vertebra and dural canal medially at 60 degree and 45 degree endoscopic approach angles. The percentage of the safe usage of transforaminal endoscopic approach was evaluated to utilize a 5 mm dilater without partial facet resection in the fusion image. The 3D lumbar nerve root sleeve angulation (3DNRA), which is the angle between the axis of the thecal sac and the nerve root sleeve, was calculated. The herniated discs were also visualized in the CT/MRI fusion image. Results: The 3DNRA became smaller from L2 to S1. The L2 3DNRA was statistically larger than those of the other root, and the S1 3DNRA was significantly smaller than the others (p < 0.05). (L2, 41.0°; L3, 35.6°; L4, 36.4°; L5, 33.9°; and S1, 23.2°). The SAP-ENR distance at 60° was greatest at L4/5 (5.9 mm). Possible needle passages at 60° to each disc level were 89.1% at L2/3, 87.0% at L3/4 and 84.8% at L4/5. However, the safe 5 mm dilater passage at 60° without bony resection to each disc level were 8.7% at L2/3, 28.3% at L3/4 and 37.0% at L4/5. The 60° corridor at L2/3 was the narrowest (p < 0.01). All herniated discs were visualized in the fusion image and the root compression site was clearly demonstrated especially with foraminal/extraforaminal herniations. Conclusion: The 3D lumbar CT/MRI fusion image enabled a combined nerve-bony assessment of Kambin’s triangle and herniated disc. A fully endoscopic 5 mm dilater may retract the exiting nerve root in more than 60% of total cases. This new imaging technique could prove to be very useful for the safety of endoscopic lumbar disc surgery.