Laminal fenestration for the treatment of lumbar nerve root foraminal stenosis

Predictors of Clinical Outcome After Endoscopic Partial Facetectomy for Degenerative Lumbar Foraminal Stenosis

OBJECTIVE

Endoscopic partial facetectomy (EPF) is an effective option for decompressing the lumbar exiting root without causing spinal instabilities in the treatment of patients with degenerative lumbar foraminal stenosis. The aim of the present study was to identify the preoperative risk factors of poor clinical outcomes after EPF in patients with degenerative lumbar foraminal stenosis.

METHODS

A total of 51 consecutive patients who had undergone EPF from 2012 to 2015 were included in the present study. The clinical outcomes were evaluated using the visual analog scale (VAS), Oswestry disability index (ODI), and Short-Form 36-item (SF-36) outcome questionnaires. The preoperative radiological risk factors were measured using the lumbar Cobb's angle, disc wedging angle, lumbar lordosis (LL), segmental lordosis, disc height index, presence of spondylolisthesis, and morphological changes (no change, horizontal collapse, vertical collapse) of the exiting root within the most stenotic level on preoperative magnetic resonance imaging.

RESULTS

The VAS, ODI, and SF-36 scores had significantly improved at the 1-month follow-up visit compared with the baseline mean values and were maintained within the 2-year follow-up period. A correlation analysis revealed significant relationships between various preoperative factors and clinical outcomes. On multiple regression analysis, the morphological change of vertical collapse significantly predicted the VAS, ODI, and SF-36 scores, and LL significantly predicted the ODI and SF-36 scores.

CONCLUSIONS

A morphological change in vertical collapse found on preoperative magnetic resonance imaging and decreased LL were significant predictors of poor clinical outcomes after EPF in the treatment of lumbar foraminal stenosis.

Clinical and Radiological Outcomes of Foraminal Decompression Using Unilateral Biportal Endoscopic Spine Surgery for Lumbar Foraminal Stenosis

Background

Since open Wiltse approach allows limited visualization for foraminal stenosis leading to an incomplete decompression, we report the short-term clinical and radiological results of unilateral biportal endoscopic foraminal decompression using 0° or 30° endoscopy with better visualization.

Methods

We examined 31 patients that underwent surgery for neurological symptoms due to lumbar foraminal stenosis which was refractory to 6 weeks of conservative treatment. All 31 patients underwent unilateral biportal endoscopic far-lateral decompression (UBEFLD). One portal was used for viewing purpose, and the other was for surgical instruments. Unilateral foraminotomy was performed under guidance of 0° or 30° endoscopy. Clinical outcomes were analyzed using the modified Macnab criteria, Oswestry disability index, and visual analogue scale. Plain radiographs obtained preoperatively and 1 year postoperatively were compared to analyze the intervertebral angle (IVA), dynamic IVA, percentage of slip, dynamic percentage of slip (gap between the percentage of slip on flexion and extension views), slip angle, disc height index (DHI), and foraminal height index (FHI).

Results

The IVA significantly increased from 6.24° ± 4.27° to 6.96° ± 3.58° at 1 year postoperatively (p = 0.306). The dynamic IVA slightly decreased from 6.27° ± 3.12° to 6.04° ± 2.41°, but the difference was not statistically significant (p = 0.375). The percentage of slip was 3.41% ± 5.24% preoperatively and 6.01% ± 1.43% at 1-year follow-up (p = 0.227), showing no significant difference. The preoperative dynamic percentage of slip was 2.90% ± 3.37%; at 1 year postoperatively, it was 3.13% ± 4.11% (p = 0.720), showing no significant difference. The DHI changed from 34.78% ± 9.54% preoperatively to 35.05% ± 8.83% postoperatively, which was not statistically significant (p = 0.837). In addition, the FHI slightly decreased from 55.15% ± 9.45% preoperatively to 54.56% ± 9.86% postoperatively, but the results were not statistically significant (p = 0.705).

Conclusions

UBEFLD using endoscopy showed a satisfactory clinical outcome after 1-year follow-up and did not induce postoperative segmental spinal instability. It could be a feasible alternative to conventional open decompression or fusion surgery for lumbar foraminal stenosis.

Bi-portal Arthroscopic Spinal Surgery (BASS) with 30° arthroscopy for far lateral approach of L5-S1 - Technical note

Background context

Lumbar foraminal stenosis or extraforaminal stenosis is a common cause of spinal cord radiculopathy. Recently, several authors have introduced an endoscopy-based spinal surgery technique.

Purpose

The study aimed to introduce far lateral approach of biportal arthroscopic technique using 30° arthroscopy for foraminal decompression of L5-S1.

Study design

Technical note.

Patient sample

12 consecutive patients.

Outcome measures

The leg VAS with modified Macnab criteria was measured.

Result

The leg VAS improved from VAS 7.5 to 1.8.

Conclusion

Far lateral approach of BASS with 30° arthroscopy is an alternative method that can decompress foraminal stenosis minimally invasively.

Clinical and radiological outcomes of endoscopic partial facetectomy for degenerative lumbar foraminal stenosis

BACKGROUND

Several different techniques exist to treat degenerative lumbar foraminal stenosis. Failure to adequately decompress the lumbar foramen may lead to failed back surgery syndrome. However, wide decompression often causes spinal instabilities or may require an additional fusion surgery. The aim of this study was to report the outcomes of endoscopic partial facetectomy (EPF) performed on patients with degenerative lumbar foraminal stenosis.

METHODS

Between 2012 and 2014, 25 consecutive patients (12 women and 13 men) who underwent EPF were included in the study. The patients were assessed before surgery and followed-up regularly during outpatient visits (preoperatively and 1, 3, 6, 12, and 24 months postoperatively). The clinical outcomes were evaluated using the visual analog scale (VAS), Oswestry Disability Index (ODI), and Short Form-36 (SF-36) outcome questionnaire. The radiological outcome was measured using the lumbar Cobb angle, disc wedging angle, lumbar lordosis (LL), slip percentage, and disc height index (DHI) in plain standing radiographs.

RESULTS

The VAS, ODI, and SF-36 scores significantly improved at 1 month of follow-up compared with the baseline mean values and were maintained within the 2-year follow-up period. There was no radiologic progression in the lumbar Cobb's angle, disc wedging angle, LL, slip percentage, and DHI between preoperatively and 2 years postoperatively. In addition, the EPF with discectomy group and the EPF group were not significantly different in terms of clinical and radiological outcomes.

CONCLUSIONS

EPF is an effective option in decompressing the lumbar exiting nerve root without causing spinal instabilities for the treatment of patients with lumbar foraminal stenosis.

Partial facetectomy for lumbar foraminal stenosis

Background. Several different techniques exist to address the pain and disability caused by isolated nerve root impingement. Failure to adequately decompress the lumbar foramen may lead to failed back surgery syndrome. However, aggressive treatment often causes spinal instability or may require fusion for satisfactory results. We describe a novel technique for decompression of the lumbar nerve root and demonstrate its effectiveness in relief of radicular symptoms. Methods. Partial facetectomy was performed by removal of the medial portion of the superior facet in patients with lumbar foraminal stenosis. 47 patients underwent the procedure from 2001 to 2010. Those who demonstrated neurogenic claudication without spinal instability or central canal stenosis and failed conservative management were eligible for the procedure. Functional level was recorded for each patient. These patients were followed for an average of 3.9 years to evaluate outcomes. Results. 27 of 47 patients (57%) reported no back pain and no functional limitations. Eight of 47 patients (17%) reported moderate pain, but had no limitations. Six of 47 patients (13%) continued to experience degenerative symptoms. Five of 47 patients (11%) required additional surgery. Conclusions. Partial facetectomy is an effective means to decompress the lumbar nerve root foramen without causing spinal instability.

Interspinous spacers for lumbar foraminal stenosis: formal trials are justified

PURPOSE

To determine whether preliminary evidence supports X-STOP implants as an effective treatment for lumbar radiculopathy secondary to foraminal stenosis, and if larger formal trials are warranted.

METHODS

Participants had a clinical diagnosis of lumbar radiculopathy supported by MRI findings of foraminal stenosis and relevant nerve root compression. Self-reported disability and pain were measured pre-operation, early and late post-operation using the widely used Oswestry Disablity Index (ODI) and the bodily pain scale of the Medical Outcomes Study 36-item Short Form Health Survey (SF-36BP). The statistical significance (paired samples t test; Wilcoxon signed ranks test), and clinical significance (Cohen's effect size; Standardised response means) of change scores was determined.

RESULTS

Fifteen people had X-STOP implants. Data pre- early- and late post-operation were available for ten. Self-reported disability and pain improved substantially by the early post operative measurement. Mean change scores (ODI = 29; SF-36BP = -45), significant at the p < 0.05 but not significant at the p < 0.001, were very large and effect sizes exceeded notably criteria for large clinical improvements (>0.80). Improvements were maintained at 2-3 years. Both scales had floor and ceiling effects implying changes may be underestimated. There were no surgical complications.

CONCLUSIONS

In this small study, X-STOP appeared safe and effective. It is less invasive than other established surgical procedures, but does not jeopardise other options in the event of failure. Large scale clinical trials are justified but floor and ceiling effects suggest that the ODI and SF-36 may not be the best choice of outcome measures for those studies.

A less invasive surgical approach in the lumbar lateral recess stenosis: direct approach to the medial wall of the pedicle

The lateral recess is one of the main compression sites in lumbar spinal canal stenosis. Lumbar nerve root is mainly entrapped by bony tissue in compression syndrome. The patient has a long history of back pain in conjunction with claudication symptoms. Besides laminotomy and facetectomy techniques, several specific surgical approaches to treat the lateral recess stenosis have been described. The surgical technique of bilateral lateral recess decompression via subarticular fenestrations used in this study is a less invasive technique, which enables to decompress the neural structures while preserving as much of the bony structures and ligamentum flavum as preferred. In 16 patients, we measured lateral recess heights with computerized tomography. The number of involved lumbar segments was one in 11 patients and two in 5 patients. The visual analogue scale (VAS) results were maintained before, 3 and 12 months after the operation. All patients benefited from the operations. Mean VAS scores were 7.0, 5.5, and 4.0, respectively. There were not any surgery-related complications. Mean follow-up period is 22.6 months. The surgical technique described and used in this study provides easy access to every zone of lateral recess and is safe and effective in treating the lumbar lateral recess stenosis syndrome.

Minimally invasive lumbar decompression

With the increasing elderly population, the number of patients presenting with symptoms secondary to lumbar stenosis can be expected to increase accordingly. Therefore, treatment of this disease process should become more prevalent, and the minimally invasive techniques offer another treatment option. As surgeons become more experienced in minimally invasive techniques, the reported advantages of the minimal access surgery, including reduction in soft tissue injury, less blood loss, shorter hospitalization, and faster recovery, should make this an attractive alternative to traditional open surgery. Continuing efforts in the minimally invasive field can be expected to yield new and potentially less invasive as well as possibly more efficacious treatment options in the future.