European Spine Journal

, Volume 22, Issue 11, pp 2481–2487 | Cite as

Exiting root injury in transforaminal endoscopic discectomy: preoperative image considerations for safety

  • Il Choi
  • Jae-Ouk Ahn
  • Wan-Soo So
  • Seung-joon Lee
  • In-Jae Choi
  • Hoon KimEmail author
Original Article



To evaluate the clinical and radiological risk factors for exiting root injuries during transforaminal endoscopic discectomy.


We retrospectively examined cohort data from 233 patients who underwent percutaneous endoscopic lumbar discectomy for lumbar disc herniation between January 1st, 2010 and December 31st, 2011. We divided the patients into the two groups: those who presented a postoperative exiting root injury, such as postoperative dysesthesia or motor weakness (Group A, n = 20), and those who did not suffer from a root injury (Group B, n = 213). We examined the clinical and radiological factors relating exiting root injuries. We measured the active working zone with the exiting root to the upper facet distance (Distance A), the exiting root to disc surface distance at the lower facet line (Distance B) and the exiting root to the lower facet distance (Distance C) in magnetic resonance imaging (MRI).


Group A exhibited a shorter Distance C (6.4 ± 1.5 versus 4.4 ± 0.8 mm, p < 0.001) and a longer operation time (67.9 ± 21.8 versus 80.3 ± 23.7 min, p = 0.017) relative to Group B. The complication rate decreased by 23 % per each 1-mm increase in Distance C (p = 0.000). In addition, the complication rate increased 1.027-fold per each 1-min increase in the operation time (p = 0.027).


We recommend measuring the distance from the exiting root to the facet at the lower disc level according to a preoperative MRI scan. If the distance is narrow, an alternative surgical method, such as microdiscectomy or conventional open discectomy, should be considered.


Endoscopy Discectomy Root injury Working zone 



Thank Dr. Hyeun Sung Kim at the Herisarang spine hospital for critical advice. Thank Andrew choe for English correction.

Conflict of interest



  1. 1.
    Kambin P, Gellman H (1983) Percutaneous lateral discectomy of the lumbar spine—a preliminary-report. Clin Orthop Relat Res 174:127–132Google Scholar
  2. 2.
    Forst R, Hausmann B (1983) Nucleoscopy—a new examination technique. Arch Orthop Trauma Surg 101:219–221PubMedCrossRefGoogle Scholar
  3. 3.
    Onik G, Helms C, Ginsburg L et al (1985) Percutaneous lumbar diskectomy using a new aspiration probe. Am J Roentgenol 144:1137–1140CrossRefGoogle Scholar
  4. 4.
    Kambin P, Nixon JE, Chait A et al (1988) Annular protrusion: pathophysiology and roentgenographic appearance. Spine (Phila Pa 1976) 13:671–675Google Scholar
  5. 5.
    Mayer HM, Brock M (1993) Percutaneous endoscopic lumbar discectomy (PELD). Neurosurg Rev 16:115–120PubMedCrossRefGoogle Scholar
  6. 6.
    Tsou PM, Yeung AT (2002) Transforaminal endoscopic decompression for radiculopathy secondary to intracanal noncontained lumbar disc herniations: outcome and technique. Spine J 2:41–48PubMedCrossRefGoogle Scholar
  7. 7.
    Knight MT, Ellison DR, Goswami A et al (2001) Review of safety in endoscopic laser foraminoplasty for the management of back pain. J Clin Laser Med Surg 19:147–157PubMedCrossRefGoogle Scholar
  8. 8.
    Hermantin FU, Peters T, Quartararo L et al (1999) A prospective, randomized study comparing the results of open discectomy with those of video-assisted arthroscopic microdiscectomy. J Bone Joint Surg Am 81:958–965PubMedGoogle Scholar
  9. 9.
    Ruetten S, Komp M, Merk H et al (2008) Full-endoscopic interlaminar and transforaminal lumbar discectomy versus conventional microsurgical technique: a prospective, randomized, controlled study. Spine (Phila Pa 1976) 33:931–939CrossRefGoogle Scholar
  10. 10.
    Yeung AT, Tsou PM (2002) Posterolateral endoscopic excision for lumbar disc herniation: Surgical technique, outcome, and complications in 307 consecutive cases. Spine (Phila Pa 1976) 27:722–731CrossRefGoogle Scholar
  11. 11.
    Cho JY, Lee SH, Lee HY (2011) Prevention of development of postoperative dysesthesia in transforaminal percutaneous endoscopic lumbar discectomy for intracanalicular lumbar disc herniation: floating retraction technique. Minim Invasive Neurosurg 54:214–218PubMedCrossRefGoogle Scholar
  12. 12.
    Min JH, Kang SH, Lee JB et al (2005) Morphometric analysis of the working zone for endoscopic lumbar discectomy. J Spinal Disord Tech 18:132–135PubMedCrossRefGoogle Scholar
  13. 13.
    Mirkovic SR, Schwartz DG, Glazier KD (1995) Anatomic considerations in lumbar posterolateral percutaneous procedures. Spine (Phila Pa 1976) 20:1965–1971CrossRefGoogle Scholar
  14. 14.
    Ahn Y, Lee SH, Park WM et al (2004) Percutaneous endoscopic lumbar discectomy for recurrent disc herniation: surgical technique, outcome, and prognostic factors of 43 consecutive cases. Spine (Phila Pa 1976) 29:E326–E332CrossRefGoogle Scholar
  15. 15.
    Weinstein JN, Lurie JD, Tosteson TD et al (2006) Surgical vs nonoperative treatment for lumbar disk herniation: the Spine Patient Outcomes Research Trial (SPORT) observational cohort. JAMA 296:2451–2459PubMedCrossRefGoogle Scholar
  16. 16.
    Weinstein JN, Lurie JD, Tosteson TD et al (2008) Surgical versus nonoperative treatment for lumbar disc herniation: four-year results for the Spine Patient Outcomes Research Trial (SPORT). Spine (Phila Pa 1976) 33:2789–2800CrossRefGoogle Scholar
  17. 17.
    Jacobs WC, Arts MP, van Tulder MW et al (2012) Surgical techniques for sciatica due to herniated disc, a systematic review. Eur Spine J 21:2232–2251PubMedCrossRefGoogle Scholar
  18. 18.
    Osterman H, Seitsalo S, Karppinen J et al (1976) (2006) Effectiveness of microdiscectomy for lumbar disc herniation: a randomized controlled trial with 2 years of follow-up. Spine (Phila Pa 1976) 31:2409–2414CrossRefGoogle Scholar
  19. 19.
    Peul WC, van Houwelingen HC, van den Hout WB et al (2007) Surgery versus prolonged conservative treatment for sciatica. N Engl J Med 356:2245–2256PubMedCrossRefGoogle Scholar
  20. 20.
    Weber BR, Grob D, Dvorak J et al (1997) Posterior surgical approach to the lumbar spine and its effect on the multifidus muscle. Spine (Phila Pa 1976) 22:1765–1772CrossRefGoogle Scholar
  21. 21.
    Kambin P, O’Brien E, Zhou L et al (1998) Arthroscopic microdiscectomy and selective fragmentectomy. Clin Orthop Relat Res 347:150–167PubMedCrossRefGoogle Scholar
  22. 22.
    Ruetten S, Komp M, Godolias G (2005) An extreme lateral access for the surgery of lumbar disc herniations inside the spinal canal using the full-endoscopic uniportal transforaminal approach-technique and prospective results of 463 patients. Spine (Phila Pa 1976) 30:2570–2578CrossRefGoogle Scholar
  23. 23.
    Ruetten S, Komp M, Godolias G (2006) A new full-endoscopic technique for the interlaminar operation of lumbar disc herniations using 6-mm endoscopes: prospective 2-year results of 331 patients. Minim Invasive Neurosurg 49:80–87PubMedCrossRefGoogle Scholar
  24. 24.
    Ruetten S, Komp M, Merk H et al (2007) Use of newly developed instruments and endoscopes: full-endoscopic resection of lumbar disc herniations via the interlaminar and lateral transforaminal approach. J Neurosurg Spine 6:521–530PubMedCrossRefGoogle Scholar
  25. 25.
    Lee SH, Kang BU, Ahn Y et al (2006) Operative failure of percutaneous endoscopic lumbar discectomy: a radiologic analysis of 55 cases. Spine (Phila Pa 1976) 31:E285–E290CrossRefGoogle Scholar
  26. 26.
    Ahn Y, Lee SH, Lee JH et al (2009) Transforaminal percutaneous endoscopic lumbar discectomy for upper lumbar disc herniation: clinical outcome, prognostic factors, and technical consideration. Acta Neurochir (Wien) 151:199–206CrossRefGoogle Scholar
  27. 27.
    Kambin P (1991) Arthroscopic microdiskectomy. Mt Sinai J Med 58:159–164PubMedGoogle Scholar
  28. 28.
    Ahn Y, Lee SH, Park WM et al (2003) Posterolateral percutaneous endoscopic lumbar foraminotomy for L5–S1 foraminal or lateral exit zone stenosis. Technical note. J Neurosurg 99:320–323PubMedCrossRefGoogle Scholar
  29. 29.
    Pedowitz RA, Garfin SR, Massie JB et al (1992) Effects of magnitude and duration of compression on spinal nerve root conduction. Spine (Phila Pa 1976) 17:194–199CrossRefGoogle Scholar
  30. 30.
    Rydevik BL, Pedowitz RA, Hargens AR et al (1991) Effects of acute, graded compression on spinal nerve root function and structure. An experimental study of the pig cauda equina. Spine (Phila Pa 1976) 16:487–493CrossRefGoogle Scholar
  31. 31.
    Olmarker K, Rydevik B, Holm S (1989) Edema formation in spinal nerve roots induced by experimental, graded compression. An experimental study on the pig cauda equina with special reference to differences in effects between rapid and slow onset of compression. Spine (Phila Pa 1976) 14:569–573CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Il Choi
    • 1
  • Jae-Ouk Ahn
    • 2
  • Wan-Soo So
    • 4
  • Seung-joon Lee
    • 4
  • In-Jae Choi
    • 4
  • Hoon Kim
    • 3
    Email author
  1. 1.Department of Neurosurgery, Asan Medical CenterUniversity of Ulsan College of MedicineSeoulKorea
  2. 2.Department of Statistics, College of MedicineSoonchunhyang UniversityAsanKorea
  3. 3.Department of NeurosurgeryBucheon St. Mary’s Hospital, The Catholic University of KoreaBucheonKorea
  4. 4.Department of NeurosurgeryThe Capital Armed Forced HospitalSeongnamKorea

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