Minimally invasive decompression for lumbar stenosis and disc herniation

Consecutive Case Series of Uniportal Full-endoscopic Unilateral Laminotomy for Bilateral Decompression in Lumbar Spinal Stenosis: Relationship between Decompression Range and Functional Outcomes

OBJECTIVE

Uniportal full-endoscopic unilateral laminotomy for bilateral decompression (UFE-ULBD) has been used to treat lumbar spinal stenosis (LSS) with satisfactory outcomes. However, a limited number of studies have investigated the relationship between decompression range and clinical outcomes. This study aimed to investigate the efficacy of UFE-ULBD for single-segment LSS and to explore the relationship between the decompression range and functional outcomes.

METHODS

Single-segment LSS patients who had undergone UFE-ULBD using an interlaminar approach between November 2021 and February 2023 were retrospectively analyzed. Patient demographics, visual analogue scale (VAS) scores for leg and back pain, Oswestry disability index (ODI) scores, modified MacNab grades, and radiological outcomes, including the decompression ratio of the disc-flava ligament space and osseous lateral recess, the enlargement ratio of superior articular process interval, lamina interval dural sac cross-sectional area (DSCA), were collected. The independent sample t-tests, paired sample t-tests, chi-square tests, Fisher's exact tests, and Pearson's and Spearman's correlation analyses were used.

RESULTS

Forty patients (23 males, and 17 females) were retrospectively enrolled in this study. The mean follow-up period was 12 months. At the last follow-up, VAS scores for leg pain and back pain decreased from 6.0 ± 0.8 to 1.0 ± 1.9 (p < 0.001), and from 6.0 ± 0.8 to 1.2 ± 1.8 (p < 0.001) respectively; ODI score decreased from 71.7 ± 6.2 to 24.3 ± 21.3 (p < 0.001). According to the modified MacNab criteria, the results were excellent in 28 (70%), good in 5 (12.5%), fair in 6 (15%), and poor in 1 (2.5%), with an excellent-good rate of 82.5%. The postoperative DSCA enlarged from 57.69 ± 21.86 to 150.75 ± 39.33 mm2 (p < 0.001), with an enlargement ratio of 189.43 ± 107.83%. No difference in clinical or radiological parameters was detected between patients with excellent, good, fair, or poor outcomes based on the modified MacNab criteria.

CONCLUSION

UFE-ULBD can provide satisfactory clinical and radiological outcomes in single-segment LSS patients. With sufficient exposure to the dural sac boundary, the functional outcome was not related to the radiological decompression range in LSS patients who had undergone UFE-ULBD.

Unilateral laminotomy with bilateral spinal canal decompression: systematic review of outcomes and complications

BACKGROUND

Unilateral laminotomy with bilateral spinal canal decompression has gained popularity recently.

AIM

To systematically review the literature of unilateral laminotomy with bilateral spinal canal decompression for lumbar spinal stenosis (LSS) aiming to assess outcomes and complications of the different techniques described in literature.

METHODS

On August 7, 2022, Pubmed and EMBASE were searched by 2 reviewers independently, and all the relevant studies published up to date were considered based on predetermined inclusion and exclusion criteria. The subject headings "unilateral laminotomy", "bilateral decompression" and their related key terms were used. The Preferred Reporting Item for Systematic Reviews and Meta-Analyses statement was used to screen the articles.

RESULTS

A total of seven studies including 371 patients were included. The mean age of the patients was 69.0 years (range: 55-83 years). The follow up duration ranged from 1 to 3 years. Rate of postoperative pain and functional improvement was favorable based on VAS, JOA, JOABPEQ, RMDW, ODI and SF-36, for example improved from a range of 4.2-7.5 preoperatively on the VAS score to a range of 1.4-3.0 postoperatively at the final follow up. Insufficient decompression was noted in 3% of the reported cases. The overall complication rate was reported at 18-20%, with dural tear at 3.6-9% and hematoma at 0-4%.

CONCLUSION

Unilateral laminotomy with bilateral decompression has favorable short- and mid-term pain and functional outcomes with low recurrence and complication rates. This, however, needs to be further confirmed in larger, long-term follow-up, prospective, comparative studies between open, and minimally invasive techniques.

Comparison of Unilateral Biportal Endoscopic Discectomy with Other Surgical Technics: A Systemic Review of Indications and Outcomes of Unilateral Biportal Endoscopic Discectomy from the Current Literature

OBJECTIVE

Unilateral biportal endoscopic (UBE) spine surgery for spinal diseases has been increasing in popularity because of its favorable outcomes. The goal of this systemic review is to analyze the status of outcomes and complications in lumbar disc herniation during UBE discectomy.

METHODS

A comprehensive search of the PubMed, Embase, Web of Science, and OVID databases published until June 30, 2021, was performed. The outcomes of interest were indications, operative time, blood loss, hospital stay, complications, visual analog scale score, and Oswestry Disability Index.

RESULTS

Seven studies were included in our research. UBE surgery for lumbar stenosis was excluded. A total of 230 patients with lumbar disc herniation were enrolled in the 7 selected studies. The mean operative time was 74.4 minutes, and the mean length of hospital stay was 4.5 days. Mean incidence of complications reported in the 7 articles was 6.2%. UBE showed shorter hospital stays than did microdiscectomy, no significant differences of Oswestry Disability Index or visual analog scale scores, and good recovery rate among other discectomy techniques (microdiscectomy, full endoscopic transforaminal endoscopic lumbar discectomy, and interlaminar endoscopic lumbar discectomy) at 1 month follow-up.

CONCLUSIONS

Even with the small number of studies and reports analyzed, biases were the main limitation of this analysis; overall, the clinical outcomes and complication rates associated with UBE discectomy were relatively good. It is clear that UBE discectomy is a good treatment choice for lumbar disc herniation, but to prevent unique UBE surgery complications, a clear understanding of the surgical procedures and careful efforts to overcome the learning curve are necessary.

Endoscopic Spinal Surgery (BESS and UESS) Versus Microscopic Surgery in Lumbar Spinal Stenosis: Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic Review and Meta-Analysis.

OBJECTIVES

Various minimally invasive surgical techniques have been developed as alternatives to conventional surgery. According to recent studies, endoscopic spinal surgery (ESS) (biportal ESS [BESS] or uniportal ESS [UESS]) is more favorable compared with microscopic spinal surgery (MSS). This systematic review and meta-analysis aimed to assess the latest evidence on the use of ESS compared with MSS in lumbar spinal stenosis.

METHODS

A systematic electronic search using PubMed, Embase, Cochrane Central Database, and Korea Med was performed until December 2019 to identify studies that compared ESS and MSS in patients with lumbar spinal stenosis.

RESULTS

Overall, 1167 patients were included from three randomized controlled trials, six retrospective cohorts, and two prospective case-control studies. This review only presented 3 direct comparative studies. The study had inherent limitations specifically in terms of the study design. Meta-analysis of hospital stay (days) showed significant difference between BESS and MSS, UESS and MSS, BESS +UESS, and MSS at the final follow-up (95% confidence interval [CI]: -3.66 to -.77; P = .003; I² = 97%, 95% CI: -2.95 to -1.22; P <.00001; I² = 90%, and 95% CI: -2.89 to -1.48; P <.00001; I² = 96%, respectively). However, meta-analysis showed no significant difference in other results.

CONCLUSIONS

Although a shorter duration of hospital stay was observed in ESS, there were no significant differences in efficacy and safety between ESS and MSS. Further studies are required to validate these results.

Surgical treatment of senile spinal diseases

Advanced age is a well-known risk factor for spinal surgery-related complications. Decisions on spine surgery in the elderly are difficult due to higher morbidity and mortality than in younger age groups. In addition, spine surgery is a kind of ‘functional surgery’ which does not directly affect the survival of patients. In recent years, individualized risk stratification has gained ground over simple chronological age-based assessment. In the elderly, frailty is one of the strongest factors which affect surgical outcomes for both cervical and thoracolumbar spine surgery, regardless of the surgical technique used. Spine surgery in the elderly have worse surgical outcomes in terms of duration of hospital stay, degree of functional recovery, and complication, readmission, and mortality rates. However, the benefit of spine surgery even in the very-elderly is substantial. In conclusion, surgical decisions should be made based on both personalized risk assessment and benefits of surgery. Recent advanced surgical techniques such as minimally invasive surgical techniques and robotics assistance are likely to be helpful in minimizing surgical complications. Therefore, advanced age in itself should not be considered as a contraindication for spine surgery.

Comparison of Clinical Outcomes Following Lumbar Endoscopic Unilateral Laminotomy Bilateral Decompression and Minimally Invasive Transforaminal Lumbar Interbody Fusion for One-Level Lumbar Spinal Stenosis With Degenerative Spondylolisthesis

Introduction: Both lumbar endoscopic unilateral laminotomy bilateral decompression (LE-ULBD) and minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) have been used to treat one-level lumbar spinal stenosis (LSS) with degenerative spondylolisthesis, while the differences of the clinical outcomes are still uncertain.

Methods: Among 60 consecutive patients included, 24 surgeries were performed by LE-ULBD and 36 surgeries were performed by MI-TLIF. Patient demographics, operation characteristics and complications were recorded. Sagittal parameters, including slip percentage (SP) and slip angle (SA) were compared. The visual analog scale (VAS) score, the Oswestry Disability Index (ODI) score, and Macnab criteria were used to evaluate the clinical outcomes. Follow-up examinations were conducted at 3, 6, 12, and 24 months postoperatively.

Results: The estimated blood loss, time to ambulation and length of hospitalization of the LE-ULBD group were shorter than the MI-TLIF group. Preoperative and final follow-up SP of the LE-ULBD group was of no significant difference, while final follow-up SP of the MI-TLIF group was significantly improved compared with preoperative SP. The postoperative mean VAS and ODI scores decreased significantly in both LE-ULBD group and MI-TLIF group. According to the modified Macnab criteria, the outcomes rated as excellent/good rate were 95.8 and 97.2%, respectively, in both LE-ULBD group and MI-TLIF group. Intraoperative complication rate of the LE-ULBD and the MI-TLIF group were 4.2 and 0%, respectively. One case of intraoperative epineurium injury was observed in the LE-ULBD group. Postoperative complication rate of the LE-ULBD and the MI-TLIF group were 0 and 5.6%, respectively. One case with transient urinary retention and one case with pleural effusion were observed in the MI-TLIF group.

Conclusion: Both LE-ULBD and MI-TLIF are safe and effective to treat one-level LSS with degenerative spondylolisthesis.

Minimally Invasive Spine Surgery: The Learning Curve of a Single Surgeon

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

The learning curve associated with the implementation of minimally invasive spinal surgery (MIS) has been the center of attention in numerous publications. So far, these studies referred to a single MIS procedure. In our view, minimally invasive surgical skills are acquired simultaneously through a variety of procedures that share common features. The aim of this study was to analyze the skills progression of a single surgeon implementing diverse minimally invasive techniques.

METHODS

We retrospectively collected all patients who underwent spinal surgery for thoracic or lumbar pathology by a single surgeon between 2012 and 2015 at a single institute. Both minimally invasive as well as open surgical techniques were analyzed; these groups were compared on the basis of surgical indications and outcomes. Skills progression analysis in reference to minimally invasive technique was performed.

RESULTS

A total of 230 patients met the inclusion criteria for this study. MIS group included higher percentage of lumbar discectomy and the open-surgery group included higher percentage of tumor resection surgery. Learning curve evaluation demonstrated increased surgical complexity, evaluated by number of levels treated, over the 4-year period, which corresponded with decreased complication rates.

DISCUSSION

A gradual increase in surgical complexity over 4 years, together with careful patient selection, enables the surgeon to maintain the rate of complication within acceptable limits. The main challenge facing the MIS community is constructing an education program for MIS surgeons in order to reduce the learning curve-induced complications.

CONCLUSION

Advancement of educational aids for MIS surgical skill improvement, including spine models, virtual and augmented reality aids and surgical simulators may reduce the learning curve of spine surgeons.

Comparison of lumbar endoscopic unilateral laminotomy bilateral decompression and minimally invasive surgery transforaminal lumbar interbody fusion for one-level lumbar spinal stenosis

BACKGROUND

The aim of the present study is to compare the clinical outcomes and postoperative complications of lumbar endoscopic unilateral laminotomy bilateral decompression (LE-ULBD) and minimally invasive surgery transforaminal lumbar interbody fusion (MIS-TLIF) to treat one-level lumbar spinal stenosis (LSS) without degenerative spondylolisthesis or deformity.

METHODS

A retrospective analysis of 112 consecutive patients of one-level LSS undergoing either LE-ULBD or MIS-TLIF was performed. Patient demographics, operation time, estimated blood loss, time to ambulation, length of hospitalization, intraoperative and postoperative complications were recorded. The visual analog scale (VAS) score for leg and back pain, the Oswestry Disability Index (ODI) score, and the Macnab criteria were used to evaluate the clinical outcomes. The healthcare cost was also recorded.

RESULTS

The operation time, estimated blood loss, time to ambulation and length of hospitalization of LE-ULBD group were shorter than MIS-TLIF group. The postoperative mean VAS and ODI scores decreased significantly in both groups. According to the modified Macnab criteria, the outcomes rated as excellent/good rate were 90.6 and 93.8% in the two groups. The mean VAS scores, ODI scores and outcomes of the modified Macnab criteria of both groups were of no significant difference. The healthcare cost of LE-ULBD group was lower than MIS-TLIF group. Two cases of intraoperative epineurium injury were observed in the LE-ULBD group. One case of cauda equina injury was observed in the LE-ULBD group. No nerve injury, dural injury or cauda equina syndrome was observed in MIS-TLIF group. However, one case with transient urinary retention, one case with pleural effusion, one case with incision infection and one case with implant dislodgement were observed in MIS-TLIF group.

CONCLUSIONS

Both LE-ULBD and MIS-TLIF are safe and effective to treat one-level LSS without degenerative spondylolisthesis or deformity. LE-ULBD is a more minimally invasive option and of less economic burden compared with MIS-TLIF. Decompression plus instrumented fusion may be not necessary for one-level LSS without degenerative spondylolisthesis or deformity.

Novel electromagnetic-based navigation for percutaneous transforaminal endoscopic lumbar decompression in patients with lumbar spinal stenosis reduces radiation exposure and enhances surgical efficiency compared to fluoroscopy: a randomized controlled trial

Background

Percutaneous transforaminal endoscopic lumbar decompression (PTELD) is an emerging surgical alternative for treating lumbar spinal stenosis (LSS). However, the foraminoplasty procedure often requires repeated fluoroscopy, and endoscopy just offers a local view. No studies have focused on decreasing radiation exposure with electromagnetic navigation assistance. This study introduces a novel electromagnetic-based navigation (EMN) endoscopic system for PTELD in patients with LSS and compares the results in navigation and fluoroscopy groups.

Methods

Eighty-eight patients with LSS were randomized into either a navigation (44 patients) or fluoroscopy group. Duration of surgery, cannula placement time, radiation dose, blood loss, intraoperative pain assessment, and postoperative hospitalization stay were evaluated. The clinical outcomes were evaluated using a visual analogue scale (VAS), the Oswestry Disability Index (ODI), 6-minute walk test, and modified Macnab criteria.

Results

Eighty-five patients were followed-up for at least 12 months. The duration of surgery and cannula placement time were significantly more efficient in the navigation group (P=0.03 and P<0.001). Intraoperative pain assessment showed significantly less pain in the navigation group (P=0.038). The radiation dose was significantly higher in the fluoroscopy group than the navigation group (P<0.001). The VAS scores for back (P<0.001) and leg (P<0.001) pain improved significantly in both groups after surgery, as did the ODI (P<0.001) scores. Improvements in walking ability and Macnab criteria assessments at the 12-month follow-up, assessed subjective by patient assessments did not differ between the two groups.

Conclusions

The EMN system used in PTELD for patients with LSS compared to fluoroscopy enhances efficiency for foraminoplasty, reduces intraoperative pain and levels of radiation exposure. It results in outcomes comparable with results using fluoroscopy.

Comparision of biportal endoscopic and microscopic decompression in treatment of lumbar spinal stenosis: A comparative study protocol

BACKGROUND

Microscopic bilateral decompression (MBD) has been suggested as an alternative to open laminectomy and fusion. Recently, percutaneous biportal endoscopic decompression (PBED) has begun to attract attention. The purpose of this retrospective study was to evaluate postoperative pain, functional disability, symptom reduction and satisfaction, and specific surgical parameters between the MBD and PBED techniques in patients with lumbar spinal stenosis (LSS).

METHODS

A retrospective review of LSS patients performed with MBD or PBED technique between May 2015 and June 2018 was conducted. Institutional review board approval in People's Hospital of Ningxia Hui Nationality Autonomous Region was obtained prior to conducting chart review and analysis. We received informed consent from all patients before surgery. The primary outcomes assessed were the preoperative to postoperative changes in leg/back pain and disability/function, patient satisfaction with the procedure, and postoperative quality of life. The secondary outcomes including duration of postoperative hospital stay, time to mobilization, postoperative analgesic use, complication rates, and baseline patient characteristics were prospectively collected.

RESULTS

The hypothesis was that the PBED technique would achieve better clinical outcomes as compared to the MBD technique in LSS.

Clinical and radiological outcomes between biportal endoscopic decompression and microscopic decompression in lumbar spinal stenosis

BACKGROUND CONTEXT

Numerous minimal invasive techniques treating lumbar spinal stenosis have been introduced. Clinical results using biportal endoscopic spinal surgery has recently been introduced as a treatment option for lumbar spinal stenosis. The purpose of this study was to compare the clinical and radiologic outcome between microscopic unilateral laminotomy bilateral decompression and biportal endoscopic unilateral laminotomy bilateral decompression in patients with degenerative lumbar spinal stenosis.

METHOD

A total of 89 patients were evaluated for this study. Only single-level patients were enrolled for accurate comparison. Patients that underwent biportal endoscopic surgery were assigned to Group A, and patients that underwent microscopic surgery were designated Group B. Clinical outcomes were evaluated using modified Macnab criteria, Oswestry Disability Index, and Visual Analog Scale. Postoperative complications were checked until final follow up. Plain radiographs before and after surgery were compared to analyze the change of alignment.

RESULT

There was a significant difference between Group A and B in VAS of back on postoperative 2 months. Other clinical measurements except for postoperative 2 months VAS of back showed no significant difference. There were no significant differences between Group A and Group B regarding preoperative and postoperative radiological findings.

CONCLUSION

Two different decompression techniques preserve the spinal structure and exhibit a favorable clinical outcome and have the advantage of not causing postoperative instability in the short term follow up. Biportal endoscopic surgery may leads to less postoperative back pain than microscopic surgery, which may allow early ambulation and shorter hospitalization period.

Primary Dural Closure in Minimally Invasive Spine Surgery Using an Extracorporeal Knot: Technical Note

BACKGROUND

Minimally invasive spine surgeries (MISS) are currently used for a wide variety of intradural spinal pathologies. Although MISS techniques have brought great benefits, primary dural closure can prove a challenge due to the narrow corridor of the tubular retractor systems.

OBJECTIVE

To present the surgical technique we developed for dural closure using an extracorporeal knot that is simple and reproducible.

METHODS

We describe the use of an extracorporeal knot for primary dural closure in MISS surgeries using standard instrumental. We illustrate this operative technique with figures and its application in a surgical case with images and demonstration video2.

RESULTS

Using our surgical technique, a watertight dural closure with separated knots was performed without specific instruments.

CONCLUSION

The use of extracorporeal knots facilitates primary dural closure in MISS surgeries.

Is biportal technique/endoscopic spinal surgery satisfactory for lumbar spinal stenosis patients?: A prospective randomized comparative study

BACKGROUND

Lumbar decompressive surgery is a standard surgical technique for lumbar spinal stenosis. Many new surgical techniques have been introduced, ranging from open surgery to minimally invasive procedures. Minimally invasive surgical techniques are preferred because patients experience less postoperative pain and shorter hospital stays. However, the success rate of minimally invasive techniques have been controversial. The object of this study was to assess the feasibility of spinal decompression using biportal technique/endoscopic surgery compared with microscopic surgery.

METHODS

Seventy lumbar spinal stenosis patients undergoing laminectomy were included in this study. A number table was used to randomize the patients into two groups: a biportal technique/endoscopic surgery group (BG-36) and a microscopic surgery group (OG-34). One surgeon performed either biportal technique/endoscopic decompression or microscopic decompression using a tubular retractor, depending on the group to which the patient was randomized. Perioperative data and clinical outcomes at postoperative 6 months were collected and analyzed.

RESULTS

The demographic data and level of surgery were comparable between the two groups. A shorter operation time (36 ± 11 vs 54 ± 9 min), less hemovac drain output (25.5 ± 15.8 vs 53.2 ± 32.1 ml), less opioid usage (2.3 ± 0.6 vs 6.5 ± 2.5 T) and shorter hospital stay (1.2 ± 0.3 vs 3.5 ± 0.8 days) were shown in BG. The BG experienced no significant differences in clinical outcomes compared with OG. Favorable clinical outcomes were shown at 6 months after surgery in both groups.

CONCLUSION

Lumbar decompressive surgery using biportal technique/endoscopy showed favorable clinical outcomes, less pain and a shorter hospital stay compared to microscopic surgery in patients with lumbar spinal stenosis.

Navigated minimally invasive unilateral laminotomy with crossover for intraoperative prediction of outcome in degenerative lumbar stenosis

BACKGROUND

Different surgical techniques have been described for treatment of degenerative lumbar stenosis (DLS). Only postoperative measures have been identified as predictors of efficacy of decompression. The objective of this study is to assess the role of navigated unilateral laminotomy with crossover to achieve and predict a satisfying decompression and outcome in DLS.

MATERIALS AND METHODS

We enrolled patients with DLS who underwent navigation-assisted unilateral laminotomy with crossover. The extent of decompression was evaluated during surgery using neuronavigation. The outcome was assessed through the Oswestry disability index (ODI) and visual analog scale (VAS) for leg pain. Outcome correlation with the extent of the intraoperative bone decompression was analyzed. Finally, the outcome, surgical time, and in-hospital length-of-stay were compared with a control group treated through standard unilateral laminotomy.

RESULTS

Twenty-five patients were treated using the navigated technique (Group A), 25 using the standard unilateral laminotomy (Group B). In Group A, a cut-off value ≥0.9 cm for bone decompression revealed to be an intraoperative predictor of good outcome, both regarding the ODI and VAS scores (P = 0.0005; P = 0.002). As compared with Group B, patients operated using the navigated technique showed similar operative times, in-hospital length-of-stay, ODI scores, but improved VAS scores for leg pain (P = 0.04).

CONCLUSIONS

The intraoperative navigated evaluation of the bone decompression could predict the outcome allowing satisfactory results in unilateral laminotomy for DLS. The navigated technique also could lead to an improved decompression of lateral recesses resulting in better control of leg pain as compared to standard unilateral laminotomy.

Is minimally invasive surgery superior to open surgery for treatment of lumbar spinal stenosis? A systematic review

PURPOSE

The purpose of this study is to review the updated evidence comparing outcomes between minimally invasive surgery (MIS) and conventional open surgery (COS) for lumbar spinal stenosis (LSS).

METHODS

All randomized controlled trials (RCTs) published from January 2005 to August 2016 were identified through PubMed and MEDLINE databases. Only RCTs including patients with LSS and with direct comparison between COS and MIS were selected for analysis. The intra- and post-operative effects of different MIS and COS on patients with LSS were evaluated for any differences.

RESULTS

We reviewed 10 RCTs comparing the effect of MIS and COS for LSS. Most trials showed that MIS rendered a shorter duration of hospital stay, lower reoperation rate, visual analogue scale (VAS), 36-Item Form Health Survey (SF-36) score, creatinine phosphokinase-skeletal muscle (CPK-MM) levels and a higher Japanese Orthopaedic Association (JOA) score. However, the intergroup differences were not statistically significant for all comparisons and were only present for selected mild cases of spinal stenosis.

CONCLUSIONS

This systematic review suggests that MIS reduces operating time, duration of hospital stay and CPK-MM levels. However, the evidence for these parameters is weak. Moreover, there is no conclusive evidence that MIS reduces reoperation or has better improvement in pain and outcome scores like VAS, SF-36 and JOA scores. The evidence is limited due to poor standardization of MIS definition, methodology and details of surgeon experience. MIS techniques should not be studied as a group, as each procedure is vastly different from each other.

Early Outcomes of Endoscopic Contralateral Foraminal and Lateral Recess Decompression via an Interlaminar Approach in Patients with Unilateral Radiculopathy from Unilateral Foraminal Stenosis

OBJECTIVE

Percutaneous endoscopic contralateral interlaminar lumbar foraminotomy (PECILF) for lumbar degenerative spinal stenosis is an established procedure. Better preservation of contralateral facet joint compared with that of the approach side has been shown with uniportal bilateral decompression. The aim of this retrospective case series was to analyze the early clinical and radiologic outcomes of stand-alone contralateral foraminotomy and lateral recess decompression using PECILF.

METHODS

Twenty-six consecutive patients with unilateral lower limb radiculopathy underwent contralateral foraminotomy and lateral recess decompression using PECILF. Their clinical outcomes were evaluated with visual analog scale leg pain score, Oswestry Disability Index, and the MacNab criteria. Completeness of decompression was documented with a postoperative magnetic resonance imaging.

RESULTS

Mean age for the study group was 62.9 ± 9.2 years and the male/female ratio was 4:9. A total of 30 levels were decompressed, with 18 patients (60%) undergoing decompression at L4-L5, 9 at L5-S1 (30%), 2 at L3-L4 (6.7%), and 1 at L2-L3 (3.3%). Mean estimated blood loss was 27 ± 15 mL per level. Mean operative duration was 48 ± 12 minutes/level. Visual analog scale leg score improved from 7.7 ± 1 to 1.8 ± 0.8 (P < 0.0001). Oswestry Disability Index improved from 64.4 ± 5.8 to 21 ± 4.5 (P < 0.0001). Mean follow-up of the study was 13.7 ± 2.7 months. According to the MacNab criteria, 10 patients (38.5%) had good results, 14 patients (53.8%) had excellent results, and 2 patients (7.7%) had fair results. One patient required revision surgery.

CONCLUSIONS

Facet-preserving contralateral foraminotomy and lateral recess decompression with PECILF is effective for treatment of lateral recess and foraminal stenosis. Thorough decompression with acceptable early clinical outcomes and minimal perioperative morbidity can be obtained with the contralateral endoscopic approach.

Stand-alone Lateral Recess Decompression Without Discectomy in Patients Presenting With Claudicant Radicular Pain and MRI Evidence of Lumbar Disc Herniation: A Prospective Study

STUDY DESIGN

A prospective study.

OBJECTIVE

The aim of this study was to analyze the outcomes of stand-alone lateral recess decompression without discectomy in patients with claudicant radicular pain and magnetic resonance imaging (MRI) showing LRS (lateral recess stenosis) with lumbar disc herniation.

SUMMARY OF BACKGROUND DATA

Discectomy is the gold standard treatment for symptomatic lumbar disc herniations refractory to conservative care. Typically, patients with positive SLR (Straight leg raising test) and flexion dominant leg pain are the ideal candidates who can be benefited from discectomy. There is a subset of patients with morphological features of lumbar disc herniation with LRS on MRI and presenting with diametrically opposite symptoms such as claudicant leg pain, extension dominant leg pain, relief on flexion, and a negative SLR. Until now, no focused prospective study in the literature highlights stand-alone lateral recess decompression in this group of patients.

METHODS

From January 2007 to June 2013, 55 patients having unilateral claudicant radicular pain were selected to undergo stand-alone lateral recess decompression with tubular retractors. Intraoperatively, disc consistency and presence of sequestrated fragments were analyzed. Visual Analogue Scale (VAS), Oswestry Disability Index (ODI) score, and Macnab criteria were used to measure outcomes.

RESULTS

Out of 55 patients, stand-alone lateral recess decompression was successfully executed in 51 patients and remaining four patients had sequestrated discs that required removal. Mean age at presentation was 54.5 years (41-67 years), male:female ratio was 1.12:1, and mean follow-up was 3.8 years (3-5.8 years). Significant improvement (P < 0.0001) was noticed between preoperative and postoperative VAS score (8.39 ± 0.84 vs. 2.5 ± 0.48) and ODI score (46.79 ± 1.85 vs. 18.71 ± 2.41). As per Macnab criteria, 94% patients were satisfied with surgery.

CONCLUSION

Stand-alone lateral recess decompression without discectomy is clinically effective for a large majority of patients with claudicant radicular pain and MRI evidence of LRS with associated lumbar disc herniation. The ability to perform it with minimal invasive techniques makes it focused and targeted with minimal morbidity.

LEVEL OF EVIDENCE

4.

Assessment of Paraspinal Muscle Cross-sectional Area After Lumbar Decompression: Minimally Invasive Versus Open Approaches

STUDY DESIGN

A retrospective, blinded analysis of imaging studies.

SUMMARY OF BACKGROUND DATA

To evaluate changes in paraspinal muscle cross-sectional area (CSA) after surgical treatment for lumbar stenosis and to compare these changes between minimally invasive and standard open approaches. The open approach to lumbar stenosis is effective, but it involves retraction and resection of muscle from the spinous process, which can result in ischemia and denervation of paraspinal musculature and may lead to muscle atrophy and pain.

OBJECTIVE

It is hypothesized that the microendoscopic decompression of stenosis (MEDS) technique will better preserve the paraspinal muscles compared with the open procedure.

MATERIALS AND METHODS

A total of 18 patients underwent a 1-level posterior decompression for lumbar stenosis, (9 open, 9 MEDS). Lumbar magnetic resonance imaging was obtained before surgery and after surgery (open approach average 16.3 mo; MEDS average 16.6 mo). CSA of paraspinal muscles were averaged over the distance of the surgical site.

RESULTS

The mean age of patients treated with the open and MEDS approaches were 55.2 and 66.4 years, respectively (P=0.07). Paraspinal muscle CSA decreased by an average of 5.4% (SD=10.6%; range, -24.5% to +7.7%) in patients treated with the open approach and increased by an average of 9.9% (SD=14.4%; range, -9.8% to +33.1%) in patients treated with MEDS (P=0.02). For the open approach, changes in CSA did not differ significantly between the left and right sides for erector spinae (P=0.35) or multifidus muscles (P=0.90). After the MEDS approach there were no significant differences between the dilated and contralateral sides with regard to change in CSA for erector spinae (P=0.85) or multifidus muscles (P=0.95).

CONCLUSIONS

Compared with the open approach for lumbar stenosis, MEDS had significantly less negative impact on the paraspinal muscle CSA. Previous reports have documented negative effects of paraspinal muscle injury, including weakness, disability, and pain. Collectively, these data suggest that the MEDS approach for lumbar decompression is less destructive to the paraspinous muscles than the open approach and may facilitate better clinical outcomes.

Minimally invasive surgery for lumbar synovial cysts with coexisting degenerative spondylolisthesis

BACKGROUND

About one third of lumbar synovial cysts are associated with degenerative spondylolisthesis. Segmental instability is thought to contribute to the pathogenesis and recurrence of synovial cysts and lumbar fusion has been advocated as a treatment of choice in the presence of spondylolisthesis. In patients with spondylolisthesis, minimally invasive resection of lumbar synovial cysts, without fusion, could minimize surgically induced segmental instability while providing good pain relief.

METHODS

Clinical and radiological outcomes of lumbar synovial cyst patients with and without spondylolisthesis were retrospectively compared. Pain outcomes were assessed with modified Macnab criteria.

RESULTS

Fifty-three patients (18 with grade 1 spondylolisthesis) underwent minimally invasive synovial cyst resection and all had either excellent or good pain outcome at ≤ 8 post- operative weeks (P = 1.000, n = 53). At > 8 post-operative weeks (mean (SD) follow-up of 200 (175) weeks), excellent or good outcomes were noted in 89% of patients without spondylolisthesis and in 75% of patients with spondylolisthesis (P = 0.425, n = 40). Four patients developed a new grade 1 spondylolisthesis at a mean follow-up of 2.6 ± 2.1 years. Nine patients were assessed for spondylolisthesis measurements at 1.2 ± 1.3 years of follow up and no significant difference was observed (5 ± 0 vs 5 ± 1 mm; P = 0.791). Two patients without spondylolisthesis and none of the patients with spondylolisthesis had a synovial cyst recurrence.

CONCLUSION

Patients with concomitant lumbar degenerative spondylolisthesis and synovial cyst can have good short- and long-term clinical outcomes with minimally invasive surgery without fusion. Post-operative segmental instability does not appear to be significant in patients with spondylolisthesis. All patients included in this article signed an informed consent for the use of their medical information for research.

Minimally Invasive Surgical Management of Thoracic Ossification of the Ligamentum Flavum Associated with X-linked Hypophosphatemia

BACKGROUND

X-linked hypophosphatemia (XLH) is the most common inherited form of renal phosphate wasting and inherited rickets. Patients have hyperplasia of fibrochondrocytes in tendons and ligaments, causing the structures to thicken and calcify. Thickening of the lamina, hypertrophy of facet joints, and calcification of spinal ligaments are sequelae of this condition and can result in central or foraminal stenosis that compresses nerve roots or the spinal cord. We present a case of XLH with calcification of the ligamentum flavum in which the patient was operated on using minimally invasive posterior decompression.

CASE DESCRIPTION

A 49-year-old man with a history of XLH presented to our emergency department with symptomatic myelopathy from multilevel thoracic stenosis. Radiographically, the calcified ligamentum flavum appeared to be the cause of the stenosis at various levels. The patient underwent a posterior decompression at the levels of compression, T4-T5, T8-T9, T9-T10, and T11-T12, via a minimally invasive spine surgery approach. Intraoperatively, the ligamentum flavum appeared to be both calcified and the source of spinal compression. Postoperatively, the patient experienced neurologic and radiographic improvement.

CONCLUSION

Patients with a history of XLH and multilevel symptomatic spine stenosis can be treated successfully and safely with a minimally invasive posterior decompression.

Elderly patients have similar outcomes compared to younger patients after minimally invasive surgery for spinal stenosis

BACKGROUND

Older patients undergo surgery for lumbar spinal stenosis in great numbers, but as a result of substantial diagnostic and surgical heterogeneity, the impact of age on results after surgery is poorly defined.

QUESTIONS/PURPOSES

We compared groups of patients younger and older than 70 years with relative clinical and surgical homogeneity to determine differences in (1) interval improvement in Oswestry Disability Index (ODI) at 6 weeks, 6 months, and 12 months postoperatively and (2) perioperative adverse events.

METHODS

We performed a subgroup analysis of an ongoing prospective observational study. Patients were divided based primarily on age (younger than 70 years [n = 68] and 70 years or older [n = 41]) and secondarily on procedure (minimally invasive decompression alone or decompression and instrumented fusion). With the exception of age and American Society of Anesthesiologists status, the two age groups were similar (p > 0.3) in baseline demographics and ODI. Mean pre- and postoperative ODI were compared between groups at 6 weeks, 6 months, and 12 months. Perioperative adverse events were also compared.

RESULTS

At all time intervals, both younger and older patients demonstrated (p = 0.05 to < 0.001) improvements in ODI. At the 1-year mark, no differences in ODI were demonstrated between the younger and older patients for decompression only (21 versus 26 [p = 0.29]) or decompression and fusion (19 versus 18 [p = 0.97]). Interval improvement in ODI was not different between younger and older patients at any time point for decompression only (6 weeks: -18 versus -20 [p = 0.66]; 6 months: -21 versus -17 [p = 0.41]; 12 months: -21 versus -15 [p = 0.29]) or decompression and fusion (6 weeks: -11 versus -12 [p = 0.58]; 6 months: -21 versus -22 [p = 0.69]; 12 months: -23 versus -27 [p = 0.97]). There were no differences in perioperative adverse events between groups (p = 0.67).

CONCLUSIONS

When clinical and surgical heterogeneity is minimized, improvements in terms of disability as measured by the ODI and the frequency of adverse events after surgery in elderly patients with lumbar spinal stenosis are comparable to those of younger patients. For patients with focal lumbar spinal stenosis, age alone should not dissuade us from considering surgical intervention if otherwise indicated.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Outcomes after decompressive laminectomy for lumbar spinal stenosis: comparison between minimally invasive unilateral laminectomy for bilateral decompression and open laminectomy: clinical article

OBJECT

The development of minimally invasive surgical techniques is driven by the quest for better patient outcomes. There is some evidence for the use of minimally invasive surgery for degenerative lumbar spine stenosis (LSS), but there are currently no studies comparing outcomes with matched controls. The object of this study was to compare outcomes following minimally invasive unilateral laminectomy for bilateral decompression (ULBD) to a standard "open" laminectomy for LSS.

METHODS

The authors conducted a prospective, 1:1 randomized trial comparing ULBD to open laminectomy for degenerative LSS. The study enrolled 79 patients between 2007 and 2009, and adequate data for analysis were available in 54 patients (27 in each arm of the study). Patient demographic characteristics and clinical characteristics were recorded and clinical outcomes were obtained using pre- and postoperative Oswestry Disability Index (ODI) scores, visual analog scale (VAS) scores for leg pain, patient satisfaction index scores, and postoperative 12-Item Short Form Health Survey (SF-12) scores.

RESULTS

Significant improvements were observed in ODI and VAS scores for both open and ULBD interventions (p < 0.001 for both groups using either score). In addition, the ULBD-treated patients had a significantly better mean improvement in the VAS scores (p = 0.013) but not the ODI scores (p = 0.055) compared with patients in the open-surgery group. ULBD-treated patients had a significantly shorter length of postoperative hospital stay (55.1 vs. 100.8 hours, p = 0.0041) and time to mobilization (15.6 vs. 33.3 hours, p < 0.001) and were more likely to not use opioids for postoperative pain (51.9% vs. 15.4%, p = 0.046).

CONCLUSIONS

Based on short-term follow-up, microscopic ULBD is as effective as open decompression in improving function (ODI score), with the additional benefits of a significantly greater decrease in pain (VAS score), postoperative recovery time, time to mobilization, and opioid use.

Spontaneous lateral sphenoid cephaloceles: anatomic factors contributing to pathogenesis and proposed classification

SUMMARY

Spontaneous lateral sphenoid cephaloceles arise from bony defects in the lateral sphenoid, in the absence of predisposing factors such as trauma, surgery, mass, or congenital skull base malformation. We reviewed CT and MR imaging findings and clinical data of 26 patients with spontaneous lateral sphenoid cephaloceles to better understand anatomic contributions to pathogenesis, varying clinical and imaging manifestations, and descriptive terminology. Two types of spontaneous lateral sphenoid cephaloceles were identified. In 15 of 26 patients, a type 1 spontaneous lateral sphenoid cephalocele was noted, herniating into a pneumatized lateral recess of the sphenoid sinus, and typically presenting with CSF leak and/or headache. In 11 of 26 patients, a type 2 spontaneous lateral sphenoid cephalocele was noted, isolated to the greater sphenoid wing without extension into the sphenoid sinus, presenting with seizures, headaches, meningitis, cranial neuropathy, or detected incidentally. All patients had sphenoid arachnoid pits, and 61% of patients had an empty or partially empty sella, suggesting that altered CSF dynamics may play a role in their genesis.

Minimally invasive unilateral pedicle screw fixation and lumbar interbody fusion for the treatment of lumbar degenerative disease

Minimally invasive unilateral pedicle screw fixation for the treatment of degenerative lumbar diseases has won the support of many surgeons. However, few data are available regarding clinical research on unilateral pedicle screw fixation associated with minimally invasive techniques for the treatment of lumbar spinal diseases. The purpose of this study was to evaluate clinical outcomes in a selected series of patients with lumbar degenerative diseases treated with minimally invasive unilateral vs classic bilateral pedicle screw fixation and lumbar interbody fusion. Patients in the unilateral group (n=43) underwent minimally invasive unilateral pedicle screw fixation with the Quadrant system (Medtronic, Memphis, Tennessee). The bilateral group (n=42) underwent bilateral instrumentation via the classic approach. Visual analog scale pain scores, Oswestry Disability Index scores, fusion rate, operative time, blood loss, and complications were analyzed. Mean operative time was 75 minutes in the unilateral group and 95 minutes in the bilateral group. Mean blood loss was 220 mL in the unilateral group and 450 mL in the bilateral group. Mean postoperative visual analog scale pain score was 3.10±0.16 in the unilateral group and 3.30±1.10 in the bilateral group. Mean postoperative Oswestry Disability Index score was 15.67±2.3 in the unilateral group and 14.93±2.6 in the bilateral group. Successful fusion was achieved in 92.34% of patients in the unilateral group and 93.56% of patients in the bilateral group. Minimally invasive unilateral pedicle screw fixation is an effective and reliable option for the surgical treatment of lumbar degenerative disease. It causes less blood loss, requires less operative time, and has a fusion rate comparable with that of conventional bilateral fixation.

Minimally invasive transforaminal lumbar interbody fusion through a unilateral approach and percutaneous osteosynthesis

OBJECTIVES

To assess a surgical technique and the postoperative outcomes of a consecutive series of 22 patients treated for degenerative lumbar spondylolisthesis (DLS) through a minimally invasive unilateral approach associating interbody fusion and percutaneous osteosynthesis.

PATIENTS AND METHODS

Twenty-two patients were included in this study, with a mean age of 60 years (range, 35-77 years). All had low-grade single-level DLS. In all cases, the technique included a posterior unilateral paramedial approach through a tubular retractor that decompressed the vertebral canal and transforaminal intervertebral cage arthrodesis. Osteosynthesis was then systematically put in place. The evaluation criteria were clinical (pain, spinal symptoms, duration of hospital stay) and radiological. The entire series was followed up for a mean of 24 months.

RESULTS

In this series, the procedure was performed with no technical problems. The mean hospital stay lasted 4.5 days. Postoperative pain assessment showed a mean VAS of 2/10 at discharge and 75% of the patients were asymptomatic at 6 months. The radiological exams showed no extrapedicular screws and the fusion rate was 95% at the last follow-up (with one patient needing surgical revision for malunion).

CONCLUSION

Transforaminal lumbar interbody fusion through a unilateral approach associated with percutaneous osteosynthesis is a reliable and effective technique in DLS surgery. The clinical and radiological results are encouraging, with low morbidity and a fusion rate comparable to conventional techniques. However, a longer follow-up will be necessary so as to assess the long-term results of this surgical strategy.

Minimally invasive microscopically assisted lumbar discectomy using the METRx X-Tube system

BACKGROUND AND PURPOSE

Lumbar discectomy with the METRx X-Tube system and operating microscope is a modification of microendoscopic discectomy. The aim of this study was to describe this method and present the results of treatment of the first 13 patients.

MATERIAL AND METHODS

Under general anaesthesia and fluoroscopic guidance, a guidewire was placed over the inferior aspect of the superior lamina. A 2.5-3 cm midline skin incision was made, followed by paramedian lumbar fascia incision. Then, dilators were sequentially introduced (muscle-splitting approach). Finally, a tubular retractor was fixed directly over the interlaminar space. Further stages of the procedure were performed using an operating microscope and standard microdiscectomy equipment. The first 13 consecutive patients operated on using this method were analysed. Twelve patients were operated on at one level and 1 at two levels. Disc herniation was centro-lateral in 10 cases, lateral in 2 and central (broad-based) in 2 patients.

RESULTS

Regression of radicular pain was noted in all patients. No postoperative complications were observed except for prolongation of wound healing in 2 patients. According to mo-dified MacNab criteria, excellent late outcome was achieved in 8 patients and good in 4 patients. There were no cases of recurrent radicular pain or need for surgical revision for herniation recurrence. One patient was reoperated on because of low back pain (implantation of an interspinous spacer).

CONCLUSIONS

Microscopically assisted lumbar discectomy using the METRx X-Tube system seems to be safe and effective. This method combines the advantages of modern minimally invasive techniques while avoiding the limitations of endoscopy.

The effect of bilateral laminotomy versus laminectomy on the motion and stiffness of the human lumbar spine: a biomechanical comparison

STUDY DESIGN

A cadaveric simulation model of the lumbar spine was used to study the intervertebral motion characteristics of the lumbar spine after bilateral laminotomy and facet-sparing laminectomy.

OBJECTIVE

To assess differences in motion patterns and lumbar spine stiffness after bilateral laminotomy versus laminectomy.

SUMMARY OF BACKGROUND DATA

Spondylolisthesis after facet-sparing laminectomy has been reported with a frequency of 8% to 31%. Bilateral laminotomies have been shown to be effective in decompressing the spine, without resection of the posterior osteo-ligamentous complex. We hypothesize that bilateral laminotomies induce significantly less iatrogenic hypermobility and less stiffness reduction than a traditional facet-sparing laminectomy in the lumbar spine.

METHODS

Six fresh frozen human cadaveric lumbar spines (L1-L5) were mounted into a spine motion simulator for testing. With physiologic follower preload, flexion/extension, lateral bending, and axial rotation moments were applied to the lumbar spine in 3 trials: (1) Intact lumbar spine-no surgery, (2) Lumbar spine after bilateral lumbar laminotomies at L2-L5, (3) Lumbar spine after full laminectomies at L2-L5. The lumbar spine kinematics were measured using a Vicon motion tracking system. Total and segmental range of motion and spine stiffness were recorded.

RESULTS

In flexion/extension, bilateral laminotomies resulted in an average increase in L2-L5 range of flexion/extension motion of 14.3%, whereas a full laminectomy resulted in an increase of 32.0% (P<0.05). Analysis per level demonstrated roughly twofold increase in motion with laminectomy compared with bilateral laminotomies (P<0.05, at every treated level). Stiffness was decreased by an average of 11.8% after the 3-level-laminotomies and by 27.2% (P<0.05) after the 3-level-laminectomy.

CONCLUSION

These data demonstrate that bilateral laminotomies induce significantly less hypermobility and less stiffness reduction compared with a full laminectomy. The preservation of the central posterior osteo-ligamentous structures may provide a stabilizing effect in preventing postdecompression spondylolisthesis.

Microdiscectomia lombar tubular com o uso de seringas descartáveis de diâmetros progressivos: resultados cirúrgicos

OBJETIVO: descrever técnica minimamente invasiva para abordagem das hérnias discais com material de baixo custo. MÉTODOS: estudo prospectivo da avaliação dos resultados cirúrgicos de dez pacientes submetidos à microdiscectomia lombar tubular com uso de seringas descartáveis de diâmetros progressivos. RESULTADOS: utilizando os critérios de MacNab modificados, 60% dos pacientes apresentaram resultados considerados excelentes, 30% bons e 10% razoáveis. O tempo médio de cirurgia foi de 70 minutos e o de permanência hospitalar, de 14 horas. CONCLUSÃO: o uso de seringas descartáveis para microdiscectomia tubular foi seguro, de baixo custo e com resultados preliminares semelhantes aos da literatura para o tratamento minimamente invasivo da hérnia discal lombar.

Lumbar spinal stenosis: syndrome, diagnostics and treatment

Lumbar spinal stenosis (LSS) comprises narrowing of the spinal canal with subsequent neural compression, and is frequently associated with symptoms of neurogenic claudication. To establish a diagnosis of LSS, clinical history, physical examination results and radiological changes all need to be considered. Patients who exhibit mild to moderate symptoms of LSS should undergo multimodal conservative treatment, such as patient education, pain medication, delordosing physiotherapy and epidural injections. In patients with severe symptoms, surgery is indicated if conservative treatment proves ineffective after 3-6 months. Clinically relevant motor deficits or symptoms of cauda equina syndrome remain absolute indications for surgery. The first randomized, prospective studies have provided class I-II evidence that supports a more rapid and profound decline of LSS symptoms after decompressive surgery than with conservative therapy. In the absence of a valid paraclinical diagnostic marker, however, more evidence-based data are needed to identify those patients for whom the benefit of surgery would outweigh the risk of developing complications. In this Review, we briefly survey the underlying pathophysiology and clinical appearance of LSS, and explore the available diagnostic and therapeutic options, with particular emphasis on neuroradiological findings and outcome predictors.