Use of newly developed instruments and endoscopes: full-endoscopic resection of lumbar disc herniations via the interlaminar and lateral transforaminal approach

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Even with good results, conventional disc operations may result in subsequent damage due to trauma. Endoscopic techniques have become the standard in many areas because of the advantages they offer intraoperatively and postoperatively in rehabilitation. The goal of this prospective study was to examine the expanded technical possibilities of full-endoscopic transforaminal and interlaminar resection of herniated lumbar discs in which the authors used newly developed optics and instruments. The focus was on questions of achieving sufficient decompression, as well as the advantages and disadvantages of the minimally invasive procedure.


Two hundred thirty-two patients underwent follow up for 2 years after undergoing surgery. In addition to general and specific parameters, the following measuring instruments were used: a visual analog scale, the German version of the North American Spine Society instrument, and the Oswestry Disability Index of low-back pain disability.

Postoperatively 84% of the patients no longer had leg pain, and 12% had only occasional pain. The results of decompression were equivalent to those of conventional procedures. The incidence of traumatization was reduced. Epidural scarring was minimized. The recurrence rate was 6.0%. No serious surgical complications were observed. Resection of the herniated disc was technically possible in all cases in which the new instruments were used.


The authors view the aforedescribed techniques, which offer the advantages of a truly minimally invasive procedure, as a sufficient and safe supplementation and alternative to conventional procedures, when the appropriate indication criteria are heeded. The new endoscope with its 4.2-mm working channel and corresponding instruments significantly reduced the technical problems.

Abbreviations used in this paper:MR = magnetic resonance; NASS = North American Spine Society; ODI = Oswestry Disability Index; VAS = visual analog scale.

Article Information

Address reprint requests to: Sebastian Ruetten, M.D., Ph.D., Department of Spine Surgery and Pain Therapy, Center for Orthopaedics and Traumatology, St. Anna Hospital Herne, Hospitalstrasse 19, 44649 Herne, Germany. email:

© AANS, except where prohibited by US copyright law.



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    Radiograph demonstrating the working area shifted by lateral access (striped line) into the epidural space due to the more tangential orientation of the spinal canal; to avoid damaging the abdominal structures (dotted line), the posterior line of the facet joints should not be crossed to reach the anterior aspect of the vertebra.

  • View in gallery

    Photograph (left) and artist's drawing (right) depicting the full-endoscopic transforaminal operation with lateral access.

  • View in gallery

    Intraoperative C-arm images. A: The dilator is bluntly inserted, and the operative sheath inserted through the dilator with beveled opening toward the intervertebral space. B: The ligamentum flavum is incised and held medial with a dissector; epidural fat is visible below it. C: The ligamentum flavum is opened laterally, and the traversing spinal nerve (short arrows) is shifted dorsally through the sequestered disc material (long arrow). D: After decompression, the dura of cauda equina (short arrows) and traversing spinal nerve (long arrow) with axilla can be seen.

  • View in gallery

    Photograph (left) and artist's drawing (right) demonstrating the full-endoscopic operation with interlaminar access.

  • View in gallery

    Photograph showing the various instruments that are known in a similar, larger form in conventional spinal surgery.

  • View in gallery

    Bar graphs demonstrating the mean VAS leg and back and ODI scores (upper) and NASS scores (lower).


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