A novel translaminar crossover approach for pathologies in the lumbar hidden zone

doi:10.1016/j.jocn.2015.01.013

Journal of Clinical Neuroscience

Volume 22, Issue 6, June 2015, Pages 1030-1035

https://doi.org/10.1016/j.jocn.2015.01.013 Get rights and content

Abstract

We report eight patients with disc herniations who underwent sequestrectomy via a crossover translaminar technique. The lateral lumbar spinal canal can be divided into several regions: the subarticular, foraminal and extraforaminal zone. Due to its difficult surgical exposure, some authors refer to part of the subarticular and foraminal region as the hidden zone. Conventional approaches involve partial or total facet joint resection, introducing risk of postoperative instability. Under fluoroscopic guidance, a high speed drill was used to create a small, angled fenestration at the base of the spinous process aimed at the contralateral hidden zone. The nerve root was visualized and disc fragments were removed without facet joint violation. Patients were registered in the International Spine Registry, Spine Tango. Numeric rating scale (NRS), Oswestry disability index (ODI) and core outcome measures index (COMI) were used to evaluate outcome after 6 weeks and 3 months. Outcome was further statistically matched with the Spine Tango pool of patients who underwent sequestrectomy via conventional techniques. Postoperative CT scans showed the translaminar crossover approach with the preserved facet joints. There was significant postoperative improvement of NRS scores and ODI at all follow-up intervals. COMI achieved significant improvement at 3 months. Statistical comparison with Spine Tango data confirmed that the translaminar crossover approach matches the clinical results of the conventional techniques. This series is a proof of principle for a successful translaminar crossover approach to the lumbar hidden zone. The outcome is not inferior to conventional inter- and translaminar routes and the technique potentially offers risk reduction for postoperative instability by preserving facet joint function, especially in the case of recurrent disease.

Introduction

As recommended by The North American Spine Society [1], localization of spinal lesions are documented according to Wiltse et al [2]. Hereby, the lateral lumbar spinal canal is divided into the subarticular (lateral recess), foraminal (pedicle) and extraforaminal (far lateral) zone. Additionally, some authors refer to part of the subarticular and foraminal region as the hidden zone, a term introduced by Macnab [3] due to difficult surgical exposure (Fig. 1). Regional pathologies include nerve root impingement due to foraminal stenosis and disc herniation. As per definition, and in contrast to the above-mentioned zones, all types of disc herniations affecting the nerve root at the same level are termed far or extreme lateral, including pre- intra- and extraforaminal herniations [4], [5]. Proper diagnosis is crucial to avoid complications such as failed back surgery syndrome [3], [6] and the optimal approach has been discussed in many studies [7], [8], [9], [10], [11], [12].

Herein, we introduce a new translaminar crossover approach to the lumbar hidden zone and discuss results of the first eight patients treated with this technique.

Section snippets

Subjects and evaluation

From February 2013 to December 2013, eight patients underwent a translaminar crossover approach by one surgeon (B.R.), who is the originator of the approach. The surgical indication was radiculopathy with sensory or motor deficit due to disc herniation in the hidden zone. Additionally, one patient demonstrated bilateral recess stenosis. Two patients had previously undergone conventional laminotomy for mediolateral disc herniation at the same level. Diagnosis was confirmed by CT scan and MRI.

Results

All figures are reported as the mean ± standard deviation. The eight patients averaged 58.5 ± 9.4 years of age (Table 1). Mean operative time was 105 ± 31.5 min and decreased with experience (first three patients: 116 ± 34 min; last three patients: 85 ± 16 min). Mean intraoperative blood loss was 270 ± 47 ml. The L3/4 (n = 3) and L4/5 (n = 3) segments were most involved.

None of the patients needed conversion to a traditional trans- or interlaminar approach. There were no intra- or postoperative complications.

Anatomical and technical considerations

The incidence of radiculopathy due to lateral nerve root impingement has been reported to be 8–11% [14], [15]. Associated pain has been described as particularly severe, which is believed to be related to direct pressure on the dorsal root ganglion [16]. The optimal approach to the pre- and intraforaminal lumbar region has been the subject of many studies [7], [8], [9], [11], [12], [17]. Initially preferred by most surgeons, the standard interlaminar route by Caspar et al. [10], [18] proved to

Conclusion

The crossover translaminar approach is a feasible technique to treat pathologies in the lumbar hidden zone. It may be especially helpful for patients with recurrent disc herniation as the approach from the contralateral side avoids operating directly through scar tissue. In recurrent patients with extensive bone loss, the approach may further reduce risk of instability due to facet joint disruption or involuntary hemilaminectomy. The technique allows concomitant approach to ipsi- and

Conflicts of Interest/Disclosures

The authors declare that they have no financial or other conflicts of interest in relation to this research and its publication.

Acknowledgments

All illustrations were created by Sebastian Zachar and Marek Molcanyi (artwork inquiries: [email protected]).

References (29)

R.S. Hood
Far lateral lumbar disc herniations
Neurosurg Clin N Am
(1993)
D.F. Fardon et al.
Nomenclature and classification of lumbar disc pathology. Recommendations of the Combined task Forces of the North American Spine Society, American Society of Spine Radiology, and American Society of Neuroradiology
Spine (Phila Pa 1976)
(2001)
L.L. Wiltse et al.
A system for reporting the size and location of lesions in the spine
Spine (Phila Pa 1976)
(1997)
I. Macnab
Negative disc exploration. An analysis of the causes of nerve-root involvement in sixty-eight patients
J Bone Joint Surg Am
(1971)
A.F. Abdullah et al.
Extreme-lateral lumbar disc herniations. Clinical syndrome and special problems of diagnosis
J Neurosurg
(1974)
L.J. O’Hara et al.
Far lateral lumbar disc herniation. The key to the intertransverse approach
J Bone Joint Surg Br
(1997)
C.V. Burton et al.
Causes of failure of surgery on the lumbar spine
Clin Orthop Relat Res
(1981)
C. Bernucci et al.
Translaminar microsurgical approach for lumbar herniated nucleus pulposus (HNP) in the “hidden zone”: clinical and radiologic results in a series of 24 patients
Spine (Phila Pa 1976)
(2007)
N. Di Lorenzo et al.
Pars interarticularis fenestration in the treatment of foraminal lumbar disc herniation: a further surgical approach
Neurosurgery
(1998)
J. Kunogi et al.
Diagnosis and operative treatment of intraforaminal and extraforaminal nerve root compression
Spine (Phila Pa 1976)
(1991)

L. Papavero et al.

The lumbar microdiscectomy

Acta Orthop Scand Suppl

(1993)

F. Segnarbieux et al.

Disco-computed tomography in extraforaminal and foraminal lumbar disc herniation: influence on surgical approaches

Neurosurgery

(1994)

F. Soldner et al.

The translaminar approach to canalicular and cranio-dorsolateral lumbar disc herniations

Acta Neurochir (Wien)

(2002)

C. Roder et al.

SSE Spine Tango-content, workflow, set-up. http://www.eurospine.org-Spine Tango

Eur Spine J

(2005)

Cited by (16)

Endoscopic and Microscopic Segmental Decompression via Translaminar Crossover Spinal Approach in Elderly Patients
2019, World Neurosurgery
Citation Excerpt :
Effective minimally invasive decompression and undercutting of the opposite side was previously achieved using uniportal navigation-guided minimally invasive–lumbar interbody fusion procedures (Figure 7C), which changed our routine of segmental decompression.17,22 Sole decompression of the contralateral upper nerve root by translaminar crossover access resulted in the translaminar crossover approach, which is an effective approach for pathologic entities in the lumbar hidden zone (Figure 8E).23 Preservation of the bony structures of the facet joints (segment to be fused) for later ossification are especially important for transfacet screw-based minimally invasive stabilization techniques.
For effective minimally invasive lumbar decompression, we changed the routine of segmental decompression. Using a high-speed drill or an ultrasound knife, we created a working channel, starting at the base of the spinous process of the upper vertebra slightly above the disc level, to target and decompress the contralateral recess, and termed it the translaminar crossover decompression (TCD). We evaluated the feasibility and compared the outcomes of a navigation-guided endoscopic translaminar crossover approach for segmental decompression (eTCD) in elderly patients with microscopic decompression using the same approach (mTCD).
A total of 740 elderly patients were enrolled in a prospective cohort study. Of the 740 patients, 297, who had undergone mTCD, and 253, who had undergone eTCD, completed a 1-year follow-up visit. In addition to the surgical data, numerical rating scales (NRSs) for back and leg pain, the Core Outcome Measures Index and Oswestry Disability Index were recorded preoperatively and 3, 6, and 12 months after surgery. The MacNab criteria were supplemented by qualitative assessment of the patients' postoperative pain-free walking distance.
A comparison of the preoperative and postoperative clinical scores showed significant improvement after TCD in both cohorts (P < 0.01): Oswestry Disability Index, from 50.3% ± 12.6% to 15.5% ± 7.43%; NRS (back), from 6.9 ± 1.9 to 2.5 ± 1.3; NRS (leg), from 8.0 ± 0.85 to 1.6 ± 0.33; Core Outcome Measures Index (back), from 7.8 ± 2.0 to 2.7 ± 1.5. No statistically significant differences were found in the outcomes between the 2 cohorts.
TCD inherently eliminated central stenosis and facilitated decompression of both recesses via mutual undercutting, with preservation of facet joint integrity.
Advantages of a Microsurgical Translaminar Approach (Keyhole Laminotomy) for Upper Lumbar Disc Herniation
2018, World Neurosurgery
Citation Excerpt :
However, in this case, wide laminectomy, including pars interarticularis and facet joint, may induce iatrogenic spondylolysis or segmental instability. To overcome this risk, Di Lorenzo et al.3 introduced the microsurgical translaminar approach laminotomy technique for foraminal LDH, and several reports over the years have demonstrated the safety and usability of this approach for hidden zone surgery in cases of lower LDH (L4-5 or L5-S1).6-12 The extent of laminectomy depends on spinal level.
To prevent risk of iatrogenic instability after surgery for upper lumbar disc herniation, we adapted a microsurgical translaminar approach (keyhole laminotomy), which allows less destructive laminotomy. We compared results of translaminar and interlaminar approaches.
The study enrolled 48 patients who underwent single-level discectomy in the upper lumbar spine (L1-2 or L2-3). Patients were allocated to 2 groups: a translaminar group (n = 20) or an interlaminar group (n = 28). Mean patient age was 57.04 ± 12.77 years, and median follow-up duration was 3.5 years (range, 1.0–7.0 years). Clinical and radiologic data were retrospectively reviewed.
Baseline characteristics, including age, sex, surgical level, and preoperative symptoms, were nonsignificantly different. At 1 year after surgery, improvement in leg pain as determined by visual analog scale was nonsignificantly different. Improvement in visual analog scale for back pain was significantly greater in the translaminar group compared with interlaminar group (mean 4.00 ± 1.56 vs. 2.45 ± 2.01, P < 0.001). Surgical outcome was not different between groups. Mean decrease in disc height at operated level was not significantly different between groups. Mean increase in segmental range of motion at surgical levels was significantly greater in the interlaminar group (−3.38 ± 4.03° vs. 1.10 ± 3.03°, P = 0.010), and mean recovery of total lumbar lordosis was significantly greater in the translaminar group (9.80 ± 5.96° vs. 0.43 ± 8.45°, P = 0.021).
The translaminar approach provides a safe and effective alternative to the classic interlaminar approach for upper lumbar disc herniation.
Adjustable Polyurethane Foam as Filling Material for a Novel Spondyloplasty: Biomechanics and Biocompatibility
2018, World Neurosurgery
Citation Excerpt :
When planning vertebral augmentation procedures with PU foam, a preoperative simulation software (e.g., as used in our center, Vertaplan [Spontech, Stuttgart, Germany]) might be useful for surgical planning. In our center, several novel surgical techniques have been developed, most of them later supported by the routine use of this software, especially in minimal hybrid lumbar interbody fusion and vector lumbar interbody fusion procedures.41-45 By using routine spinal dynamic radiographic images in combination with a radiographic marker ball for size comparison as input data, the simulation software not only helps to determine the necessary expansion distances in fusion procedures but might further prove helpful in planning spondyloplasty procedures.
To investigate the biomechanics and biocompatibility of polyurethane (PU) foam with adjustable stiffness as a filling material for a novel spondyloplasty that is designed to reduce the risk of postoperative adjacent level fractures.
Sixty individual porcine lumbar vertebrae were randomly split into 4 groups: A, B, C, and D. Group A served as unmodified vertebral body controls. Groups B, C, and D consisted of hollowed vertebral bodies. Vertebrae of groups C and D were filled with adjustable PU foams of different stiffness. The compressive strength and stiffness of vertebrae from groups A–D were recorded and analyzed. 3T3 mouse fibroblasts were cultured with preformed PU foams for 4 days to test biocompatibility.
The strength and stiffness of the hollowed groups were lower than in group A. However, the differences were not statistically significant between group A and group C (P > 0.05), and were obviously different between group A and group B or group D (P < 0.01 and <0.05, respectively). Moreover, the strength and stiffness after filling foams in group C or group D were significantly greater than in group B (P < 0.01 and <0.05, respectively). Live/dead staining of 3T3 cells confirmed the biocompatibility of the PU foam.
The new PU foam shows adaptability regarding its stiffness and excellent cytocompatibility in vitro. The results support the clinical translation of the new PU foams as augmentation material in the development of a novel spondyloplasty.
Surgical Approaches to the Lumbar Hidden Zone: Current Strategies and Future Directions
2015, EBioMedicine
Full-endoscopic foraminoplasty for highly down-migrated lumbar disc herniation
2022, BMC Musculoskeletal Disorders
The Contralateral Approach to intra- and Extraforaminal Lumbar Disk Herniations: Surgical Technique and Review of Surgical Procedures
2022, Journal of Neurological Surgery, Part A: Central European Neurosurgery

View all citing articles on Scopus

¹: These authors have contributed equally to the manuscript.

View full text

Technical NoteA novel translaminar crossover approach for pathologies in the lumbar hidden zone

Abstract

Introduction

Section snippets

Subjects and evaluation

Results

Anatomical and technical considerations

Conclusion

Conflicts of Interest/Disclosures

Acknowledgments

Neurosurg Clin N Am

Nomenclature and classification of lumbar disc pathology. Recommendations of the Combined task Forces of the North American Spine Society, American Society of Spine Radiology, and American Society of Neuroradiology

Spine (Phila Pa 1976)

A system for reporting the size and location of lesions in the spine

Spine (Phila Pa 1976)

Negative disc exploration. An analysis of the causes of nerve-root involvement in sixty-eight patients

J Bone Joint Surg Am

Extreme-lateral lumbar disc herniations. Clinical syndrome and special problems of diagnosis

J Neurosurg

Far lateral lumbar disc herniation. The key to the intertransverse approach

J Bone Joint Surg Br

Causes of failure of surgery on the lumbar spine

Clin Orthop Relat Res

Translaminar microsurgical approach for lumbar herniated nucleus pulposus (HNP) in the “hidden zone”: clinical and radiologic results in a series of 24 patients

Spine (Phila Pa 1976)

Pars interarticularis fenestration in the treatment of foraminal lumbar disc herniation: a further surgical approach

Neurosurgery

Diagnosis and operative treatment of intraforaminal and extraforaminal nerve root compression

Spine (Phila Pa 1976)

The lumbar microdiscectomy

Acta Orthop Scand Suppl

Disco-computed tomography in extraforaminal and foraminal lumbar disc herniation: influence on surgical approaches

Neurosurgery

The translaminar approach to canalicular and cranio-dorsolateral lumbar disc herniations

Acta Neurochir (Wien)

SSE Spine Tango-content, workflow, set-up. http://www.eurospine.org-Spine Tango

Eur Spine J

Technical Note
A novel translaminar crossover approach for pathologies in the lumbar hidden zone