A Mobile Outside-in Technique of Transforaminal Lumbar Endoscopy for Lumbar Disc Herniations
August 7th, 2018
Here we present a protocol of a novel outside-in technique of transforaminal endoscopic discectomy for lumbar disc herniations. The technical aspects of the technique, the wide indications of use, and the results of the treatment in 184 patients are described in detail.
The treatment model it is for combating degenerative rheumitis. It has been continuously evolving from open surgery and fixation to microdiscectomy to endoscopy as demonstrated here in. The advantages of full endoscopic spine surgeries are less soft tissue dissection, reduce the blood loss, and half the remission or the functional recovery, and the quality of life the next month.
Adjust the patient in the prone position on the radiolucent operating table with the spine in slight flexion and use a marking pen and an image intensifier to mark the midline of the spine as well as the extent of the iliac crest. To indicate the paraspinal skin entry point along the center of the disc space, use the manual back assessment method to check the borderline between the back muscles and the abdominal muscles and mark the skin entry points just medial to this borderline at the mid disc level in both anteroposterior and lateral x-rays. Next, infiltrate two milliliters of subcutaneous local anesthetic around the entry point and make a one centimeter skin incision in the desensitized skin.
Insert an 18 gauge spinal needle through the incision at a 25 to 35 degree horizontal angle passing the needle under the image intensifier through the fascia and the back muscles and docking the needle at Camben's triangle near the intervertebral disc. Then, deliver 1.5 milliliters of contrast dye through the needle tip to check the free epidural space within the triangle. Using fluoroscopy, insert the needle into the discal space followed by a delivery of 2 milliliters of 0.8%indigo carmine mixed with contrast agent.
For insertion of the endoscope, first insert a guide wire over the needle into the discal space and remove the needle. Slide an obturator through the guide wire into Camben's triangle and anchor the obturator over the surface of the disc space. Then, insert the working cannula through the obturator followed by the introduction of the endoscope into the triangle.
Observe the epidural fat and soft tissues from the triangle to the entry into the disc space and use the radio frequency coagulator to clear the soft tissue and blood vessels over the annulus. Use an annular cutter to perform an annular fenestration and enter the annulus under endoscopic vision. Insert the bevel of the working cannula into the fenestrated annulus and lever the cannula downward to obtain an exact half and half view of the epidural and disc spaces.
After sufficient decompression of the protruded disc change the trajectory of the cannula toward the symptomatic disc area and check the free floating dural sack exiting route and traversing route to confirm that all free fragments of the disc are removed. Then, rotate the working channel and the endoscope to free the epidural space and image the patient by MRI on the day after the surgery. In this representative clinical study, the age of the study group was 50 plus or minus 16 years and the male to female ratio was two to one.
The patients were further divided by type of disc prolapse with over 97%of patients reporting good to excellent MacNab criteria at surgical follow up, and recurrence observed in only 15 out of the 190 levels operated on. More, improvement in the visual analog scale and Oswestry Disability Index scores was noted immediately after the surgery, remaining statistically significant through follow up. The future applications of the described technique are for all wide area of disc lumbar prolapses.
Even patients with high canal compromise and a down migrated disc can be adequately managed by percutaneous endoscopic transformal lumbar discectomy or PTLD. By precisely targeting the compressing element of the disc this technique can provide an optimal region within the frame to help achieve the desired results. The mobile outside and PTLD technique can be used to treat all types of lumbar disclination including high canal compromise due to the mobility of the working canal toward the target point.
This technique can be applied to all types of lumbar disclination at all lumbar levels.
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Overview
This article presents a novel outside-in technique for transforaminal endoscopic discectomy aimed at treating lumbar disc herniations. The protocol details the technical aspects, indications for use, and treatment outcomes in 184 patients.
Key Study Components
Area of Science
- Neurosurgery
- Endoscopic techniques
- Spinal disorders
Background
- Degenerative rheumitis is a condition that affects spinal health.
- Traditional surgical methods have evolved towards minimally invasive techniques.
- Endoscopic spine surgeries offer advantages such as reduced tissue damage and quicker recovery.
- This study focuses on a specific endoscopic discectomy technique.
Purpose of Study
- To describe a new surgical protocol for lumbar disc herniations.
- To evaluate the effectiveness of the outside-in technique.
- To analyze patient outcomes post-surgery.
Methods Used
- Patients positioned prone on a radiolucent table with slight spinal flexion.
- Use of imaging to mark surgical entry points.
- Local anesthetic infiltration at the entry point.
- One centimeter skin incision made for access.
Main Results
- Detailed outcomes from 184 patients treated with the technique.
- Reduction in blood loss and soft tissue dissection noted.
- Improved functional recovery and quality of life reported.
- Wide indications for use of the technique established.
Conclusions
- The outside-in technique is effective for lumbar disc herniations.
- Minimally invasive approaches can enhance patient recovery.
- Further studies may solidify its place in surgical practice.
Frequently Asked Questions
Executive Industry Relevance
This article describes a mobile outside-in technique for transforaminal lumbar endoscopy that enables precise targeting of disc prolapse across anatomical variants. The method supports hypothesis testing in degenerative disc disease models by allowing direct visualization and decompression of neural elements. Its versatility in managing all disc prolapse types, including high canal compromise and migrated discs, provides a reproducible preclinical model for evaluating minimally invasive spinal interventions.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Scientific Value: Enables interrogation of therapeutic hypotheses by visualizing disc material removal and neural decompression in situ.
- Operational Value: Provides a standardized approach to access the epidural space via Camben's triangle for consistent target engagement.
Screening & Assay Development
- Scientific Value: Facilitates preparation of validated biological systems through annular fenestration and cannula positioning for disc space evaluation.
- Operational Value: Supports assay standardization via mobile working cannula trajectory adjustment to symptomatic disc areas.
Translational & Preclinical Research
- Scientific Value: Offers disease-relevant system modeling by treating all lumbar disc prolapse types, including superior/inferior migrated and far lateral variants.
- Operational Value: Ensures translational continuity through postoperative MRI documentation of decompression completeness.
Pipeline & Workflow Integration
The technique integrates into discovery workflows by enabling anatomical target validation, quantitative outcome measurement, and cross-functional reproducibility in spinal disorder models.
- Discovery Biology: Supports hypothesis testing and pathway clarification via direct endoscopic visualization of annulus and disc space.
- Screening: Describes assay readiness through reproducible cannula insertion and obturator anchoring in the discal space.
- Analytics: Highlights quantitative dependent variable measurements including VAS leg pain, ODI, and Macnab criteria for outcome comparison.
- Translational Research: Connects to preclinical continuity through documented decompression on postoperative MRI across disc prolapse subtypes.
- Enterprise Reuse: Frames the mobile outside-in approach as a reusable capability for lumbar levels L1-L5/S1.
Operational & Enterprise Impact
- Scientific Value: Predictive confidence in target validation through complete disc fragment removal and dural sac route confirmation.
- Operational Value: Standardization and reproducibility via prone positioning, image-guided entry, and consistent operative time (35 ± 12 min).
- Strategic Value: Better go/no-go decisions through 97% good to excellent Macnab outcomes and low recurrence (7.89%).
- Portfolio Impact: Risk-adjusted prioritization enabled by applicability to all disc types and lumbar levels.
Implementation Considerations
- Requires expertise in fluoroscopic guidance and endoscopic spinal navigation.
- Needs instrumentation including 18 gauge spinal needle, obturator, working cannula, endoscope, and radio frequency coagulator.
- Demands cross-team standardization in patient positioning, marking techniques, and anesthetic infiltration protocols.
- Involves adaptation considerations across lumbar levels (L1-S1) and disc prolapse morphologies.
- Practical limitation: Technique relies on precise landing within the foramen and may require trajectory adjustment for symptomatic disc targeting.
