Midterm outcome after a microsurgical unilateral approach for bilateral decompression of lumbar degenerative spondylolisthesis

Comparison of the results of open PLIF versus UBE PLIF in lumbar spinal stenosis: postoperative adjacent segment instability is lesser in UBE

OBJECTIVE

To compare the difference in efficacy between open PLIF and UBE for lumbar spinal stenosis and the effect on postoperative adjacent segment instability.

METHOD

The clinical data of 37 patients with PLIF and 32 patients with UBE for lumbar spinal stenosis were retrospectively analyzed to compare the differences in perioperative conditions and short- and medium-term outcomes.

RESULTS

All 69 patients completed the surgery successfully. The operating time, number of intraoperative fluoroscopies and hospital days were higher in the UBE group than in the open PLIF group. Intraoperative bleeding and postoperative drainage were lower than in the open PLIF group (P < 0.05). The visual analogue scale (VAS) of low back pain was lower in the UBE group than in the open PLIF group at 1 month and 3 months postoperatively (P < 0.05), and there were no statistically significant VAS scores for low back pain in the two groups at 1 day and 6 months postoperatively (P > 0.05). Leg pain VAS scores were lower in the UBE group than in the open PLIF group at 1 month, 3 months and 6 months postoperatively (P < 0.05), and leg pain VAS scores were not statistically significant in both groups at 1 day postoperatively (P > 0.05). The ODI index was lower in the UBE group than in the open PLIF group at 1 day and 1 month postoperatively (P < 0.05) and was not statistically significant in the two groups at 3 months and 6 months postoperatively (P > 0.05). There was no statistically significant difference between the two groups in postoperative interbody height, sagittal diameter of the spinal canal, efficacy of modified MacNab and interbody fusion (P > 0.05). The open PLIF group was more prone to postoperative adjacent vertebral instability than the UBE group, and the difference was statistically significant (P < 0.05).

CONCLUSION

With appropriate indications, the open PLIF group and the UBE group had similar short- and medium-term clinical outcomes for the treatment of lumbar spinal stenosis, but patients in the UBE group had better symptomatic improvement than the open PLIF group at 3 months postoperatively, and the effect on postoperative adjacent vertebral instability was smaller in the endoscopic group than in the open PLIF group.

Does Tobacco Smoking Affect the Postoperative Outcome of MIS Lumbar Decompression Surgery?

BACKGROUND

Tobacco smoking is a major cause of morbidity and mortality worldwide. Several authors reported a significant negative impact of smoking on the outcome of spinal surgeries. However, comparative studies on the effect of smoking on the outcome of minimally invasive (MIS) spinal decompression are rare with conflicting results. In this study, we aimed to evaluate clinical outcomes and postoperative complications following MIS decompression in current and former smoking patients compared to those of non-smoking patients.

METHODS

We used our prospectively collected database to retrospectively analyse the records of 188 consecutive patients treated with MIS lumbar decompression at our institution between November 2013 and July 2017. Patients were divided into groups of smokers (S), previous smokers (PS) and non-smokers (N). The S group and the PS group comprised 31 and 40 patients, respectively. The N group included 117 patients. The outcome measures included perioperative complications, revision surgery and length of stay. Patient-reported outcome measures included a visual analogue scale (VAS) for back pain and leg pain, as well as the Oswestry disability index (ODI) for evaluating functional outcomes.

RESULTS

Demographic variables, comorbidity and other preoperative variables were comparable between the three groups. A comparison of perioperative complications and revision surgery rates showed no significant difference between the groups. All groups showed significant improvement in their ODI and VAS scores at 12 and 24 months following surgery. As shown by a multivariate analysis, current smokers had lower chances of improvement, exceeding the minimal clinical important difference (MCID) in ODI and VAS for leg pain at 12 months but not 24 months postoperatively.

CONCLUSIONS

Our findings show that except for a possible delay in improvement in leg pain and disability, tobacco smoking has no substantial adverse impact on complications and revision rates following MIS spinal decompressions.

Lumbar spinal stenosis - surgical outcome and the odds of revision-surgery: Is it all due to the surgeon?

BACKGROUND

Surgical decompression is the intervention of choice for lumbar spinal stenosis (LSS) when non-operative treatment has failed. Apart from acute complications such as hematoma and infections, same-level recurrent lumbar stenosis and adjacent-segment disease (ASD) are factors that can occur after index lumbar spine surgery.

OBJECTIVE

The aim of this retrospective case series was to evaluate the outcome of surgery and the odds of necessary revisions.

METHODS

Patients who had undergone either decompressive lumbar laminotomy or laminotomy and spinal fusion due to lumbar spinal stenosis (LSS) between 2000 and 2011 were included in this analysis. Demographic, perioperative and radiographic data were collected. Clinical outcome was evaluated using numeric rating scale (NRS), the symptom subscale of the adapted version of the german Spinal Stenosis Measure (SSM) and patient-sreported ability to walk.

RESULTS

Within the LSS- cohort of 438 patients, 338 patients underwent decompression surgery only, while instrumentation in addition to decompression was performed in 100 cases (22.3%). 38 patients had prior spinal operations (decompression, disc herniation, fusion) either at our hospital or elsewhere. Thirty-five intraoperative complications were documented with dural tear with CSF leak being the most common (33/35; 94.3%). Postoperative complications were defined as complications that needed surgery and differentiated between immediate postoperative complications (⩽ 3 weeks post operation) and complications that needed revisions surgery at a later date. Within all patients 51 revisions were classified as immediate complications of the index operation with infections, neurological deficits and hematoma being the most common. Within this group only 22 patients had fusion surgery in the first place, while 29 were treated by decompression. Revision surgery was indicated by 53 patients at a later date. While 4 patients decided against surgery, 49 revision surgeries were planned. 28 were performed at the same level, 10 at the same level plus an adjacent level, and 10 were executed at index level with indications of adjacent level spinal stenosis, adjacent level spinal stenosis plus instability and stand-alone instability. Pre- operative VAS score and ability to walk improved significantly in all patients.

CONCLUSIONS

While looking for predictors of revision surgery due to re-stenosis, instability or same/adjacent segment disease none of these were found. Within our cohort no significant differences concerning demographic, peri-operative and radiographic data of patients with or without revision wer noted. Patients, who needed revision surgery were older but slightly healthier while more likely to be male and smoking. Surprisingly, significant differences were noted regarding the distribution of intraoperative and early postoperative complications among the 6 main surgeons while these weren't obious within the intial index group of late revisions.

Revision surgery following minimally invasive decompression for lumbar spinal stenosis with and without stable degenerative spondylolisthesis: a 5- to 15-year reoperation survival analysis

OBJECTIVE

Minimally invasive decompression (MID) is an effective procedure for lumbar spinal stenosis (LSS). Long-term follow-up data on reoperation rates are lacking. The objective of this retrospective cohort study was to evaluate reoperation rates in patients with LSS who underwent MID, stratified for degenerative lumbar spondylolisthesis (DLS), with a follow-up between 5 and 15 years.

METHODS

All consecutive patients with LSS who underwent MID between 2002 and 2011 were included. All patients had neurogenic claudication from central and/or lateral recess stenosis, without or with up to 25% of slippage (grade I spondylolisthesis), and no obvious dynamic instability on imaging (increase in spondylolisthesis by ≥ 5 mm demonstrated on supine-to-standing or flexion-extension imaging). Reoperation rates defined as any operation on the same or adjacent level were assessed. Revision decompression alone was considered if the aforementioned clinical and radiographic criteria were met; otherwise, patients underwent a minimally invasive posterior fusion.

RESULTS

A total of 246 patients (mean age 66 years) were included. Preoperative spondylolisthesis was present in 56.9%. The mean follow-up period was 8.2 years (range 5.0-14.9 years). The reoperation rates in patients with and without spondylolisthesis were 15.7% and 15.1%, respectively; fusion was required in 7.1% and 7.5%, with no significant difference (redecompression only, p = 0.954; fusion, p = 0.546). For decompression only, the mean times to reoperation were 3.9 years (95% CI 1.8-6.0 years) for patients with DLS and 2.8 years (95% CI 1.3-4.2 years) for patients without DLS; for fusion, the mean times to reoperation were 3.1 years (95% CI 1.0-5.3 years) and 3.1 years (95% CI 1.1-5.1 years), respectively.

CONCLUSIONS

In highly selected patients with stable DLS and leg-dominant pain from central or lateral recess stenosis, the long-term reoperation rate is similar between DLS and non-DLS patients undergoing MIS decompression.

Long-Term Pain Characteristics and Management Following Minimally Invasive Spinal Decompression and Open Laminectomy and Fusion for Spinal Stenosis

Background and Objectives: To compare the long-term pain characteristics and its chronic management following minimally invasive spinal (MIS) decompression and open laminectomy with fusion for lumbar stenosis. Materials and Methods: The study cohort included patients with a minimum 5-year postoperative follow-up after undergoing either MIS decompression or laminectomy with fusion for spinal claudication. The primary outcome of interest was chronic back and leg pain intensity. Secondary outcome measures included pain frequency during the day, chronic use of non-opioid analgesics, narcotic medications, medical cannabinoids, and continuous interventional pain treatments. Results: A total of 95 patients with lumbar spinal stenosis underwent one- or two-level surgery for lumbar spinal stenosis between April 2009 and July 2013. Of these, 50 patients underwent MIS decompression and 45 patients underwent open laminectomy with instrumented fusion. In the fusion group, a higher percentage of patients experienced moderate-to-severe back pain with 48% compared to 21.8% of patients in the MIS decompression group (p < 0.01). In contrast, we found no significant difference in the reported leg pain in both groups. In the fusion group, 20% of the patients described their back and leg pain as persistent throughout the day compared to only 2.2% in the MIS decompression group (p < 0.05). A trend toward higher chronic dependence on analgesic medication and repetitive pain clinic treatments was found in the fusion group. Conclusions: MIS decompression for the treatment of degenerative spinal stenosis resulted in decreased long-term back pain and similar leg pain outcomes compared to open laminectomy and instrumented fusion surgery.

Epidural hemostasis by autologous fat graft in minimally invasive surgery for lumbar spinal stenosis: In vivo experimental study

BACKGROUND

Epidural hemostasis needs to use small, adapted material in minimally invasive surgery, including bilateral decompression via a unilateral approach for lumbar spinal stenosis. Most surgeons avoid external material for hemostasis because of possible neural tissue damage or complications. We compared epidural hemostasis in minimally invasive surgery by fat graft versus gelatin sponge.

METHODS

The design was a prospective randomized controlled in-vivo human experimental study. The 24 levels operated on for lumbar spinal stenosis were evaluated in two groups: Group A (control group: gelatin sponge) and Group B (experimental group: fat graft). International Normalized Ratio and Prothrombin Time were assessed preoperatively. Number of cotton hemostats and systolic and diastolic blood pressure were assessed intraoperatively. Epidural hemorrhage area, spinal cord size and ratio of epidural hemorrhage area to spinal cord size were evaluated on early postoperative lumbar MRI.

RESULTS

Mean epidural hemorrhage area in groups A and B was respectively 1.3±0.5 and 1.2±0.6cm², and mean spinal cord size 1.2±0.6 and 1.8±0.6cm² on early postoperative axial lumbar MRI. The two groups did not significantly differ in ratio of epidural hemorrhage/spinal cord size or number of intraoperative hemostats (P=0.36, and P=0.71).

CONCLUSIONS

The autologous fat graft ensured sufficient and safe epidural hemostasis without serious adverse events in minimally invasive spinal surgery, and is preferable as autologous tissue is easily and quickly harvested. The surgeon feels safe with this technique and does not need external hemostatic agents.

Long-Term Functional Outcomes of Endoscopic Decompression with Destandau Technique for Lumbar Canal Stenosis

Study Design

Retrospective study of patients with lumbar canal stenosis (LCS) operated using endoscopic unilateral laminotomy with bilateral decompression (ULBD).

Purpose

This study aimed to provide a detailed description of the technique of endoscopic decompression in LCS along with a description of the surgical anatomy and its advantages. We also discuss the clinical outcomes in patients operated using this technique.

Overview of Literature

In 1999, the results with the use of microscopic ULBD were published. Microscopic/microendoscopic decompression using tubular retractor system showed good to excellent results in studies that compared such techniques with midline decompression. The first description of the use of endoscope in spine surgery was in 1988 when it was used for discectomy. With advancements and familiarity with the techniques, full endoscopic surgery has found application in LCS treatment.

Methods

The clinical records of 953 patients who were operated between 1998 and 2008 were analyzed in 2018. Along with patient characteristics, information about return to daily activities, complication rates, and functional outcomes using Prolo score was assessed.

Results

L4–L5 was the most common level for which surgery was performed. Two-level decompression was performed in 116 patients; 89.5% patients were able to return to their daily activities after 2 weeks. Functional outcomes as per the Prolo score were reported by patients as excellent, good, and poor in 89.85%, 1.59%, and 8.55%, respectively. Repeat surgery was required at same level in 16 patients and at a different level in 21 patients. Total 605 patients (63.49%) were symptom-free during the 70-month follow-up, while 344 complained of residual back pain, and four complained of persistent leg pain.

Conclusions

ULBD using the Endospine system achieves adequate decompression in most cases and is a good alternative to open laminectomy, with the advantage of avoiding damage to the structural integrity of the spine and preserving soft tissue attachments.

Semi-Circumferential Decompression: Total En-Bloc Ligamentum Flavectomy to Treat Lumbar Spinal Stenosis with Two-Level Degenerative Spondylolisthesis

INTRODUCTION

Despite technical developments in decompression without fusion, many studies still assert that instability could be increased in patients with spinal stenosis and lumbar degenerative spondylolisthesis after spinal decompression surgery without fusion. Thus, this study aimed to describe and assess the clinical outcomes of the semi-circumferential decompression (SCD) technique used for microsurgical en-bloc total ligamentum flavectomy with preservation of the facet joint in treating patients who have lumbar spinal stenosis with two-level degenerative spondylolisthesis.

METHODS

We retrospectively analyzed the clinical and radiologic outcomes of 14 patients who had spinal stenosis with two-level Meyerding grade I degenerative spondylolisthesis. We evaluated improvements in back pain and radiating pain using a visual analogue scale (VAS) and the Oswestry Disability Index (ODI). We have also examined the occurrence of spinal instability on a radiological exam using slip percentage and slip angle.

RESULTS

The mean VAS score of back pain and radiating pain has been determined to decrease significantly from 6.7 to 3.3 and from 8.6 to 2.7, respectively. Meanwhile, the ODI score significantly improved from 27.3 preoperatively to 9.8 postoperatively. Statistically significant change was not observed in the slip percentage in both upper and lower levels. Dynamic slip percentage, which is defined as the difference in the slip percentage between flexion and extension, also did not significantly change. No statistically significant change was found in the slip angle and dynamic slip angle.

CONCLUSIONS

SCD is a recommendable procedure that can improve clinical results. This procedure does not cause spinal instability when treating patients who have spinal stenosis with two-level degenerative spondylolisthesis.

Complications rate of and risk factors for the unplanned reoperation of degenerative lumbar spondylolisthesis in elderly patients: a retrospective single-Centre cohort study of 33 patients

Background

The study was to investigate the complications rate of and risk factors for unplanned reoperation among elderly patients who underwent posterior lumbar fusion (PLF) for degenerative lumbar spondylolisthesis (DLS).

Methods

A total of 1100 DLS patients who were older than 60 years were reviewed from January 2006 to December 2016. 33 patients underwent unplanned reoperations and were analysed and divided into two groups (group A: posterolateral fusion, 650 patients; group B: intervertebral fusion, 450 patients). Sex, body mass index (BMI), radiographic data and clinical outcome data were analysed to evaluate the complications rate of and the risk factors for unplanned reoperations.

Results

A total of 33 patients underwent unplanned reoperations (3%). The patients were followed up for an average of 4.20 ± 2.25 years (group A) and 4.32 ± 2.54 years (group B) without a significant difference. Significant differences were found in mean age, levels of involvement, hospital stay, surgery time, and blood loss between the groups. The causes of unplanned operation were wound infection, screw misplacement, neurological deficit, nonunion, and screw fracture, which were significant except for wound infection between the groups. Higher BMI (obesity), diabetes mellitus (DM), more bleeding and sex (female) were risk factors for complications. Cases of screw misplacement, neurological deficit, nonunion and screw fracture in group A were more significant than those in group B.

Conclusion

Patients with higher BMI, DM, older age, posterolateral fusion, and female sex predicted a higher incidence of unplanned reoperations. Spine surgeons may need to pay more attention to their preoperative training and to improving surgical techniques that could reduce the reoperation rate.

Unilateral biportal endoscopic decompression for degenerative lumbar canal stenosis

Background

Unilateral biportal endoscopic (UBE) decompression is a minimally invasive (MI) approach to treat degenerative lumbar canal stenosis (DLCS). Decompression can be performed in a clear and magnified surgical field with proper control of normal saline inflow and outflow.

Methods

Clinical and radiographic data of 81 consecutive patients of DLCS treated between July 2018 and Feb 2019 using UBE techniques were reviewed. They were 38 males and 43 females with an average age of 70.2. Sixty-nine had pure canal stenosis and 12 patients had associated spondylolisthesis. Bilateral decompression via unilateral laminotomy was performed from the side on patients with more severe neurological symptoms. This is a retrospective study from chart review and image analysis. Therefore, we don't have formal ethical information for this study, and it is not mandatory in our hospital.

Results

At the final follow-up, the mean VAS for low back pain was improved from 4.3±3.0 to 1.2±1.0 and the VAS for leg symptoms was improved from 7.3±2.2 to 0.9±0.7. The mean JOA score and ODI was significantly improved from 13.3±7.9 to 25.3±5.0 and from 54.6±16.9 to 14.6±12.6, respectively. Modified Macnab criteria were excellent in 47 patients (58.0%), good in 29 (35.8%), fair in 5 (6.2%). The average hospital stay was 3.6±2.4 days. MRI before and after the operation showed the cross-sectional dural area (CSDA) was significantly increased from 71.4±36.5 to 177.3±59.2 mm², corresponding to a 201.9%±188.0% increase. The percentage of facet joint preservation was 84.2% on the approach side and 92.9% on the contralateral side. Complications included 4 dural tears, 1 transient motor weakness, 1 inadequate decompression, and 1 epidural hematoma.

Conclusions

With UBE techniques, decompression for DLCS can be performed safely and effectively. The soft tissue and facet joint destruction are minimized; therefore, it is possible to avoid spinal fusion as well as to preserve the segmental stability.

Tandem Microscopic Slalom Technique: The Use of 2 Microscopes Simultaneously Performing Unilateral Laminotomy for Bilateral Decompression in Multilevel Lumbar Spinal Stenosis

STUDY DESIGN

Technical note, retrospective case series.

OBJECTIVE

Lumbar stenosis can be effectively treated using tubular unilateral laminotomy for bilateral decompression (ULBD). For multilevel stenosis, a multilevel ULBD through separate, alternating crossover approaches has been described as the "slalom technique." To increase efficacy, we introduced this approach with 2 microscopes simultaneously.

METHODS

We collected data on 13 patients, with multilevel lumbar stenosis, operated at our institution between 2015 and 2016 by the aforementioned technique. We assessed surgical time (ST), estimated blood loss (EBL), complications, and revision surgeries. Furthermore, we provide a stepwise instruction for performing the tandem microscopic slalom technique in a safe and efficient manner.

RESULTS

The mean age of the patients was 68 ± 8 years. The ST per level was 68 ± 19 minutes with an EBL per level of 39 ± 30 mL. We had no intraoperative complications and none of our patients required a revision surgery during a mean follow-up of 12 months.

CONCLUSIONS

We have shown that this technique is feasible and can be performed safely for multisegmental lumbar spinal stenosis with minimal tissue trauma and low EBL. Furthermore, randomized controlled studies with a larger sample size may be necessary to drive any final conclusions.

[Unilateral approach for over the top bilateral lumbar decompression]

OBJECTIVE

The main goal is bilateral microsurgical decompression of the cauda equina using a unilateral over the top approach. The challenge is to achieve decompression with minimal iatrogenic trauma to anatomical structures in the approach region and in the target area.

INDICATIONS

Degenerative spinal disorders including lumbar central stenosis, lumbar lateral recess spinal stenosis, and foraminal narrowing. This technique is performed in patients presenting primarily with neurogenic claudication, leg or buttock symptoms, heaviness in the legs with or without radicular symptoms, with or without neurological deficits, and comparable MRI findings. There are no limitations regarding number of affected segments or the extent of narrowing.

CONTRAINDICATIONS

All available conservative treatment modalities not exhausted. Lack of serious neurological deficit.

SURGICAL TECHNIQUE

Minimally invasive, muscle-sparing and facet-joint-sparing bilateral enlargement of the lumbar spinal canal through a unilateral microsurgical cross-over approach.

POSTOPERATIVE MANAGEMENT

Patients are mobilized early 4-6 h postoperatively. Light sports activities (e.g., ergometer cycling, swimming) are allowed after 2 weeks. The same is true for the return to normal daily or work activities except for heavy physical work (usually 4 weeks out of work). Soft lumbar brace for 4 weeks (optional).

RESULTS

The clinical outcomes are good to excellent. Meta-analyses and large case series report success rates for microsurgical decompression procedures of 73.5-95%. The reoperation rates are low (0.5-10%).

In Degenerative Spondylolisthesis, Unilateral Laminotomy for Bilateral Decompression Leads to Less Reoperations at 5 Years When Compared to Posterior Decompression With Instrumented Fusion: A Propensity-matched Retrospective Analysis

STUDY DESIGN

Multicenter retrospective cohort study.

OBJECTIVE

The aim of this study was to compare reoperation rates at 5-year follow-up of unilateral laminotomy for bilateral decompression (ULBD) versus posterior decompression with instrumented fusion (Fusion) for patients with low-grade degenerative spondylolisthesis (DS) with lumbar spinal stenosis (LSS) in a multicenter database.

SUMMARY OF BACKGROUND DATA

Controversy exists regarding whether fusion should be used to augment decompression surgery in patients with LSS with DS. For years, the standard has been fusion with standard laminectomy to prevent postoperative instability. However, this strategy is not supported by Level 1 evidence. Instability and reoperations may be reduced or prevented using less invasive decompression techniques.

METHODS

We identified 164 patients with DS and LSS who underwent ULBD between January 2007 and December 2011 in a multicenter database. These patients were propensity score-matched on age, sex, race, and smoking status with patients who underwent Fusion (n = 437). Each patient required a minimum of 5-year follow-up. The primary outcome was 5-year reoperation. Secondary outcome measures included postoperative complication rates, blood loss during surgery, and length of stay. Logistic regression models were used to estimate the odds ratio of the 5-year reoperation rate between the two surgical groups.

RESULTS

The reoperation rate at 5-year follow-up was 10.4% in the ULBD group and 17.2% in the Fusion group. ULBD reoperations were more frequent at the index surgical level; Fusion reoperations were more common at an adjacent level. The two types of operations had similar postoperative complication rates, and both groups tended to have fusion reoperations.

CONCLUSION

For patients with stable DS and LSS, ULBD is a viable, durable option compared to fusion with decreased blood loss and length stay, as well as a lower reoperation rate at 5-year follow-up. Further prospective studies are required to determine the optimal clinical scenario for ULBD in the setting of DS.

LEVEL OF EVIDENCE

3.

[Minimally invasive decompression techniques for spinal cord stenosis]

BACKGROUND

Lumbar spinal canal stenosis is frequently found among elderly patients and significantly limits their quality of life. Non-surgical therapy is an initial treatment option; however, it does not eliminate the underlying pathology. Surgical decompression of the spinal canal has now become the treatment of choice.

OBJECTIVE

Minimalization of surgical approach strategies with maintaining sufficient decompression of the spinal canal and avoiding disadvantages of macrosurgical techniques, monolateral paravertebral approach with bilateral intraspinal decompression, specific surgical techniques.

MATERIALS AND METHODS

Minimally invasive decompression techniques using a microscope or an endoscope are presented and different surgical strategies depending on both the extent (mono-, bi-, and multisegmental) and the location of the stenosis (intraspinal central, lateral recess, foraminal) are described.

RESULTS

Minimally invasive microscopic or endoscopic decompression procedures enable sufficient widening of the spinal canal. Disadvantages of macrosurgical procedures (e. g., postoperative instability) can be avoided. The complication spectrum overlaps partially with that of macrosurgical interventions, albeit with significantly less marked severity. Subjective patient outcome is clearly improved.

CONCLUSIONS

Referring to modern minimally invasive decompression procedures, surgery of lumbar spinal canal stenosis represents a rational and logical treatment alternative, since causal treatment of the pathology is only possible with surgery.

Unilateral Laminotomy with Bilateral Decompression: A Case Series Studying One- and Two-Year Outcomes with Predictors of Minimal Clinical Improvement

OBJECTIVE

To assess factors that may predict failure to improve at 12 and 24 months after unilateral laminotomy with bilateral decompression (ULBD) for the management of lumbar spinal stenosis.

METHODS

A database of 255 patients who underwent microdecompression surgery by a single orthopedic spine surgeon between 2014 and 2018 was queried. Patients who underwent primary single-level ULBD of the lumbar spine were included. Visual analog scale (VAS) for back pain and leg pain and Oswestry Disability Index (ODI) results were collected preoperatively and at 12 and 24 months postoperatively. Demographic, radiographic, and operative factors were assessed for associations with failure to improve. Clinically important improvement was defined as reaching or surpassing the previously established minimum clinically important difference for ODI (12.8) and not requiring revision.

RESULTS

A total of 68 patients were included. Compared with preoperative values for back pain, leg pain, and ODI (7.32, 7.53, and 51.22, respectively), there were significant improvements on follow-up at 12 months (2.89, 2.23, and 22.40, respectively; P < 0.001) and 24 months (2.80, 2.11, 20.32, respectively; P < 0.001). Based on the defined criteria, 50 patients showed clinically important improvement after ULBD. Of the 18 patients who failed to improve, 12 required revision. Independent predictors of failure to improve included female sex (adjusted odds ratio, 5.06; 95% confidence interval, 1.49-21.12; P = 0.014) and current smoker status (adjusted odds ratio, 5.39; 95% confidence interval, 1.39-23.97; P = 0.018).

CONCLUSIONS

ULBD for the management of lumbar spinal stenosis leads to clinically important improvement that is maintained over a 24-month follow-up period. Female sex and tobacco smoking are associated with poorer outcomes.

Decompression Versus Fusion for Grade I Degenerative Spondylolisthesis: A Meta-Analysis

STUDY DESIGN

Meta-analysis of evidence level I to IV studies.

OBJECTIVE

To compare decompression alone versus decompression plus fusion in the treatment of grade I degenerative spondylolisthesis (DS).

METHODS

Following established guidelines, we systematically reviewed 3 electronic databases to assess studies evaluating patients with grade I DS. We stratified all patients into 2 cohorts; the first cohort underwent a decompression-type surgery, and the second cohort underwent decompression plus fusion. We noted clinical outcomes, complications, reoperations, and surgical details such as blood loss. Descriptive statistics and random-effects models were used to determine the specified outcome metrics with 95% confidence intervals (CIs).

RESULTS

In both cohorts, the pain (legs and lower back) significantly decreased and the physical component of the Short Form 36 showed better patient clinical outcomes. The decompression cohort had a 5.8% complication rate (95% CI = 1.7-2.1), and the decompression plus fusion cohort had an 8.3% complication rate (95% CI = 5.5-11.6). The reoperation rate was higher in the decompression-only cohort (8.5%; 95% CI = 2.9-17.0) compared with the decompression plus fusion cohort (4.9%; 95% CI = 2.5-7.9).

CONCLUSIONS

There does not appear to be any advantage of one procedure over the other. Patients undergoing decompression alone tended to be older with a higher percentage of leg pain, whereas patients additionally undergoing fusion tended to be younger with more lower back pain. The decompression-only cohort had fewer complications but a higher revision rate.

Management of symptomatic degenerative low-grade lumbar spondylolisthesis

Degenerative low-grade lumbar spondylolisthesis is the most common form of spondylolisthesis.

The majority of patients are asymptomatic and do not require surgical intervention.

Symptomatic patients present with a combination of lower back pain, radiculopathy and/or neurogenic claudication and may warrant surgery if non-operative measures fail.

There is widespread controversy regarding the indications for surgery and appropriate treatment strategies for patients with this type of spondylolisthesis.

This article provides a comprehensive evidence-based review of the available literature to support the management of degenerative low-grade spondylolisthesis.

Cite this article: EFORT Open Rev 2018;3:620-631. DOI: 10.1302/2058-5241.3.180020.

Minimally invasive decompression in patients with degenerative spondylolisthesis associated with lumbar spinal stenosis. Report of a surgical series and review of the literature

We reported the results of minimally invasive spinal decompression (MISD) in patients with degenerative spondylolisthesis (DS) associated with lumbar spinal stenosis (LSS) and performed a literature review in order to evaluate the clinical and radiological outcomes, the complications and reoperation rate of MISD procedures in these patients. Data of 28 patients submitted to MISD for DS associated to LSS were reviewed. We evaluated the Visual Analogue Scale (VAS) both for low back pain (LBP) and legs pain, the Oswestry Disability Index (ODI) and the degree of the slippage. A PubMed search of the English literature was conducted. Only papers with more than 10 patients and reporting explicitly data of patients with DS were included in the analysis. We found a statistically significant improvement of LBP, legs pain and ODI in our series. The degree of slippage was stable at follow-up (FU) with no need of reoperation. No major complications occurred. In our literature review, we were able to analyze the differences in ODI in 156 patients and the differences in Japanese Orthopedic Association (JOA) score in 218 patients. We observed a statistically significant improvement of ODI and JOA score at FU compared to pre-operative. The percentage of slippage, evaluated in 283 patients, was unchanged at FU compared to pre-operative. The overall complication rate was 1.6%. The overall reoperation rate was 4.5%. MISD procedures are safe and effective in patients with DS associated to LSS and are associated to low morbidity and significant improvement of disability without progression of slippage.

Lumbar Spinal Stenosis Associated With Degenerative Lumbar Spondylolisthesis: A Systematic Review and Meta-analysis of Secondary Fusion Rates Following Open vs Minimally Invasive Decompression

Background

Decompression without fusion is a treatment option in patients with lumbar spinal stenosis (LSS) associated with stable low-grade degenerative spondylolisthesis (DS). A minimally invasive unilateral laminotomy (MIL) for "over the top" decompression might be a less destabilizing alternative to traditional open laminectomy (OL).

Objective

To review secondary fusion rates after open vs minimally invasive decompression surgery.

Methods

We performed a literature search in Pubmed/MEDLINE using the keywords "lumbar spondylolisthesis" and "decompression surgery." All studies that separately reported the outcome of patients with LSS+DS that were treated by OL or MIL (transmuscular or subperiosteal route) were included in our systematic review and meta-analysis. The primary end point was secondary fusion rate. Secondary end points were total reoperation rate, postoperative progression of listhetic slip, and patient satisfaction.

Results

We identified 37 studies (19 with OL, 18 with MIL), with a total of 1156 patients, that were published between 1983 and 2015. The studies' evidence was mostly level 3 or 4. Secondary fusion rates were 12.8% after OL and 3.3% after MIL; the total reoperation rates were 16.3% after OL and 5.8% after MIL. In the OL cohort, 72% of the studies reported a slip progression compared to 0% in the MIL cohort, respectively. After OL, satisfactory outcome was 62.7% compared to 76% after MIL.

Conclusion

In patients with LSS and DS, minimally invasive decompression is associated with lower reoperation and fusion rates, less slip progression, and greater patient satisfaction than open surgery.

Treatment for Degenerative Lumbar Spondylolisthesis: Current Concepts and New Evidence

PURPOSE OF REVIEW

Current guidelines for the optimal treatment degenerative spondylolisthesis are weak and based on limited high-quality evidence.

RECENT FINDINGS

There is some moderate evidence that decompression alone may be a feasible treatment with lower surgical morbidity and similar outcomes to fusion when performed in a select population with a low-grade slip. Similarly, addition of interbody fusion may be best suited to a subset of patients with high-grade degenerative spondylolisthesis, although this remains controversial. Minimally invasive techniques are increasingly being utilized for both decompression and fusion surgeries with more and more studies showing similar outcomes and lower postoperative morbidity for patients. This will likely be an area of continued intense research. Finally, the role of spondylolisthesis reduction will likely be determined as further investigation into optimal sagittal balance and spinopelvic parameters is conducted. Future identification of ideal thresholds for sagittal vertical axis and slip angle that will prevent progression and reoperation will play an important role in surgical treatment planning. Current evidence supports surgical treatment of degenerative spondylolisthesis. While posterolateral spinal fusion remains the treatment of choice, the use of interbodies and decompressions without fusion may be efficacious in certain populations. However, additional high-quality evidence is needed, especially in newer areas of practice such as minimally invasive techniques and sagittal balance correction.

Clinical and radiographic outcomes of bilateral decompression via a unilateral approach with transforaminal lumbar interbody fusion for degenerative lumbar spondylolisthesis with stenosis

BACKGROUND CONTEXT

Laminectomy with posterior lumbar interbody fusion (PLIF) has been shown to achieve satisfactory clinical outcomes, but it leads to potential adverse consequences associated with extensive disruption of posterior bony and soft tissue structures.

PURPOSE

This study aimed to compare the clinical and radiographic outcomes of bilateral decompression via a unilateral approach (BDUA) with transforaminal lumbar interbody fusion (TLIF) and laminectomy with PLIF in the treatment of degenerative lumbar spondylolisthesis (DLS) with stenosis.

STUDY DESIGN

This is a prospective cohort study.

PATIENT SAMPLE

This study compared 43 patients undergoing BDUA+TLIF and 40 patients undergoing laminectomy+PLIF.

OUTCOME MEASURES

Visual analog scale (VAS) for low back pain and leg pain, Oswestry Disability Index (ODI), and Zurich Claudication Questionnaire (ZCQ) score.

METHODS

The clinical outcomes were assessed, and intraoperative data and complications were collected. Radiographic outcomes included slippage of the vertebra, disc space height, segmental lordosis, and final fusion rate. This study was supported by a grant from The National Natural Science Foundation of China (81572168).

RESULTS

There were significant improvements in clinical and radiographic outcomes from before surgery to 3 months and 2 years after surgery within each group. Analysis of leg pain VAS and ZCQ scores showed no significant differences in improvement between groups at either follow-up. The mean improvements in low back pain VAS and ODI scores were significantly greater in the BDUA+TLIF group than in the laminectomy+PLIF group. No significant difference was found in the final fusion rate at 2-year follow-up. The BDUA+TLIF group had significantly less blood loss, shorter length of postoperative hospital stay, and lower complication rate compared with the laminectomy+PLIF group.

CONCLUSIONS

When compared with the conventional laminectomy+PLIF procedure, the BDUA+TLIF procedure achieves similar and satisfactory effects of decompression and fusion for DLS with stenosis. The BDUA+TLIF procedure appears to be associated with less postoperative low back discomfort and quicker recovery.

Clinical and Radiological Study Focused on Relief of Low Back Pain After Decompression Surgery in Selected Patients With Lumbar Spinal Stenosis Associated With Grade I Degenerative Spondylolisthesis

STUDY DESIGN

A retrospective study.

OBJECTIVE

The aim of the present study was to identify the clinical and radiological features of low back pain (LBP) that was relieved after decompression alone of lumbar spinal stenosis (LSS) associated with grade I lumbar degenerative spondylolisthesis (LDS).

SUMMARY OF BACKGROUND DATA

Although decompression and fusion are generally the recommended surgical treatments of LDS, several authors have reported that some patients with LDS could obtain good clinical results including relief from LBP by decompression alone. The pathogenesis of relief from LBP after decompression is, however, not known.

METHODS

Forty patients with LSS associated with grade I LDS, who underwent a minimally invasive surgical-decompression were enrolled in the present study. All patients complained preoperatively of predominantly leg-related symptoms and LBP (≥ 4 points on Numeric Rating Scale). Clinical and radiological assessments were performed 1 year after surgery (a relief of LBP: Numeric Rating Scale reduction ≥3 points and valuation ≤3 points) and at the last follow-up. We conducted a comparative study between patient groups with and without the relief from LBP (groups R and N, respectively).

RESULTS

Twenty-nine patients were distributed to group R and the remaining 11 patients to group N. Preoperatively, there was a significant difference between the two groups for age and radiographic flexibility for lumbar extension. Postoperatively, there was a positive correlation between improvement in both LBP and leg symptoms. The clinical outcomes of group R were significantly better than those of group N throughout follow-up period (mean 37 mo). In group R, sagittal lumbopelvic radiographic parameters improved significantly after surgery.

CONCLUSION

Although the causes of LBP are varied in each patients, our results show that concomitant LSS itself might cause LBP in some patients with grade I LDS, because it involves impingement of the neural tissue and discordant sagittal lumbopelvic alignment.

LEVEL OF EVIDENCE

3.

Baastrup's Disease Is Associated with Recurrent of Sciatica after Posterior Lumbar Spinal Decompressions Utilizing Floating Spinous Process Procedures

STUDY DESIGN

Retrospective case-control study.

PURPOSE

To determine whether kissing spine is a risk factor for recurrence of sciatica after lumbar posterior decompression using a spinous process floating approach.

OVERVIEW OF LITERATURE

Kissing spine is defined by apposition and sclerotic change of the facing spinous processes as shown in X-ray images, and is often accompanied by marked disc degeneration and decrement of disc height. If kissing spine significantly contributes to weight bearing and the stability of the lumbar spine, trauma to the spinous process might induce a breakdown of lumbar spine stability after posterior decompression surgery in cases of kissing spine.

METHODS

The present study included 161 patients who had undergone posterior decompression surgery for lumbar canal stenosis using a spinous process floating approaches. We defined recurrence of sciatica as that resolved after initial surgery and then recurred. Kissing spine was defined as sclerotic change and the apposition of the spinous process in a plain radiogram. Preoperative foraminal stenosis was determined by the decrease of perineural fat intensity detected by parasagittal T1-weighted magnetic resonance imaging. Preoperative percentage slip, segmental range of motion, and segmental scoliosis were analyzed in preoperative radiographs. Univariate analysis followed by stepwise logistic regression analysis determined factors independently associated with recurrence of sciatica.

RESULTS

Stepwise logistic regression revealed kissing spine (p=0.024; odds ratio, 3.80) and foraminal stenosis (p<0.01; odds ratio, 17.89) as independent risk factors for the recurrence of sciatica after posterior lumbar spinal decompression with spinous process floating procedures for lumbar spinal canal stenosis.

CONCLUSIONS

When a patient shows kissing spine and concomitant subclinical foraminal stenosis at the affected level, we should sufficiently discuss the selection of an appropriate surgical procedure.

"Slalom": Microsurgical Cross-Over Decompression for Multilevel Degenerative Lumbar Stenosis

Objective. Selective, bilateral multisegmental microsurgical decompression of lumbar spinal canal stenosis through separate, alternating cross-over approaches. Indications. Two-segmental and multisegmental degenerative central and lateral lumbar spinal stenosis. Contraindications. None. Surgical Technique. Minimally invasive, muscle, and facet joint-sparing bilateral decompression of the lumbar spinal canal through 2 or more alternating microsurgical cross-over approaches from one side. Results. From December 2010 until December 2015 we operated on 202 patients with 2 or multisegmental stenosis (115 f; 87 m; average age 69.3 yrs, range 51-91 yrs). All patients were suffering from symptoms typical of a degenerative lumbar spinal stenosis. All patients complained about back pain; however the leg symptoms were dominant in all cases. Per decompressed segment, the average OR time was 36 min and the blood loss 45.7 cc. Patients were mobilized 6 hrs postop and hospitalization averaged 5.9 days. A total of 116/202 patients did not need submuscular drainage. 27/202 patients suffered from a complication (13.4%). Dural tears occurred in 3.5%, an epidural hematoma in 5.5%, a deep wound infection in 1.98%, and a temporary radiculopathy postop in 1.5%. Postop follow-up ranged from 12 to 24 months. There was a significant improvement of EQ 5 D, Oswestry Disability Index (ODI), VAS for Back and Leg Pain, and preoperative standing times and walking distances.

Clinical and Radiological Comparison between Ipsilateral and Contralateral Side Canal Decompression Using an Unilateral Laminotomy Approach

Objective

To compare the clinical and radiological outcome of both sides using the unilateral approach.

Methods

Unilateral laminotomy was performed to achieve bilateral decompression. Thirty-nine patients who underwent this procedure were analyzed prospectively using the Oswestry Disability Index (ODI), the visual analog scale (VAS) pain score to evaluate symptoms in both legs, and the radiological morphometric index to calculate the anteriorposterior diameter and midcanal width. The incidence of complications from this approach was then evaluated.

Results

The mean follow-up time was 12.2 months. The mean ODI was 48.4 preoperatively and 14.2 postoperatively. The mean dural sac widening of the ipsilateral side (187.0%) was significantly larger (p<0.01) than that of the the contralateral side (145.6%). The VAS improvement ratio ([preoperative VAS score-postoperative VAS score]/[preoperative VAS score]×100) for the pain in each leg was 75.4%(ipsilateral side) and 73.7%(contralateral side). While the VAS improvement ratio for pain in each side was significantly reduced, the difference in the VAS ratio between sides was statistically insignificant (p=0.64). There were 2 cases (5.1%) of dural tearing during the procedure, 1 case (2.6%) of transient paresthesia of nerve roots, and 2 cases (5.1%) of transient paresthesia of the contralateral nerve root. The transient paresthesias of nerve roots never lasted more than 2 weeks.

Conclusion

This technique allows for significant decompression of the contralateral canal and excellent clinical outcomes without troublesome complications. Although ipsilateral the dural sac widening was significantly larger than contralateral side, the difference in the clinical outcome between sides was statistically insignificant.

Unilateral tubular approach for bilateral laminotomy: effect on ipsilateral and contralateral buttock and leg pain

PURPOSE

Tubular laminotomy is an effective procedure for treatment of lumbar spinal stenosis (LSS) and lateral recesses stenosis. Most surgeons familiar with the procedure agree that the tubular approach appears to afford a more complete decompression of the contralateral thecal sac and nerve root, as compared to the ipsilateral approach. With this study we sought to answer the question whether this is reflected in clinically significant differences between the ipsilateral and contralateral side pain improvements.

METHODS

In a retrospective case study, patients with LSS and lateral recesses stenosis who started out with VAS scores that were similar on the right and left side were included. All patients underwent a tubular (MIS) "over the top" laminotomy from a unilateral approach and through one incision. Surgeries were performed by a single surgeon in a single center. At the last follow-up, the extent of VAS score improvement on the approach (ipsilateral) side was compared to that of the contralateral side.

RESULTS

Thirty-three patients were included in. At the latest follow-up of 25.8 ± 3.4 months, there were statistically significant improvements in ODI and back VAS scores (p = 0.002 and p < 0.0001, respectively). In addition, buttock VAS scores were significantly improved both on the ipsilateral and the contralateral side (p < 0.001, and p = 0.001, respectively). Similarly, leg VAS scores were improved significantly on both sides (p < 0.001, and p = 0.001, respectively). There were no statistically significant differences between the extent of pain improvement on the ipsilateral and the contralateral side.

CONCLUSIONS

MIS tubular laminotomy through a unilateral approach results in clinically effective bilateral decompression of LSS and lateral recesses, regardless of the approach side.

Guideline summary review: An evidence-based clinical guideline for the diagnosis and treatment of degenerative lumbar spondylolisthesis

BACKGROUND CONTEXT

The North American Spine Society's (NASS) Evidence-Based Clinical Guideline for the Diagnosis and Treatment of Degenerative Lumbar Spondylolisthesis features evidence-based recommendations for diagnosing and treating degenerative lumbar spondylolisthesis. The guideline updates the 2008 guideline on this topic and is intended to reflect contemporary treatment concepts for symptomatic degenerative lumbar spondylolisthesis as reflected in the highest quality clinical literature available on this subject as of May 2013. The NASS guideline on this topic is the only guideline on degenerative lumbar spondylolisthesis included in the Agency for Healthcare Research and Quality's National Guideline Clearinghouse (NGC).

PURPOSE

The purpose of this guideline is to provide an evidence-based educational tool to assist spine specialists when making clinical decisions for patients with degenerative lumbar spondylolisthesis. This article provides a brief summary of the evidence-based guideline recommendations for diagnosing and treating patients with this condition.

STUDY DESIGN

A systematic review of clinical studies relevant to degenerative spondylolisthesis was carried out.

METHODS

This NASS spondyolisthesis guideline is the product of the Degenerative Lumbar Spondylolisthesis Work Group of NASS' Evidence-Based Guideline Development Committee. The methods used to develop this guideline are detailed in the complete guideline and technical report available on the NASS website. In brief, a multidisciplinary work group of spine care specialists convened to identify clinical questions to address in the guideline. The literature search strategy was developed in consultation with medical librarians. Upon completion of the systematic literature search, evidence relevant to the clinical questions posed in the guideline was reviewed. Work group members used the NASS evidentiary table templates to summarize study conclusions, identify study strengths and weaknesses, and assign levels of evidence. Work group members participated in webcasts and in-person recommendation meetings to update and formulate evidence-based recommendations and incorporate expert opinion when necessary. The draft guidelines were submitted to an internal peer review process and ultimately approved by the NASS Board of Directors. Upon publication, the Degenerative Lumbar Spondylolisthesis guideline was accepted into the NGC and will be updated approximately every 5 years.

RESULTS

Twenty-seven clinical questions were addressed in this guideline update, including 15 clinical questions from the original guideline and 12 new clinical questions. The respective recommendations were graded by strength of the supporting literature, which was stratified by levels of evidence. Twenty-one new or updated recommendations or consensus statements were issued and 13 recommendations or consensus statements were maintained from the original guideline.

CONCLUSIONS

The clinical guideline was created using the techniques of evidence-based medicine and best available evidence to aid practitioners in the care of patients with degenerative lumbar spondylolisthesis. The entire guideline document, including the evidentiary tables, literature search parameters, literature attrition flow chart, suggestions for future research, and all of the references, is available electronically on the NASS website at https://www.spine.org/Pages/ResearchClinicalCare/QualityImprovement/ClinicalGuidelines.aspx and will remain updated on a timely schedule.

Semi-Circumferential Decompression: Microsurgical Total en-bloc Ligamentum Flavectomy to Treat Lumbar Spinal Stenosis with Grade I Degenerative Spondylolisthesis

Background

To describe and assess clinical outcomes of the semi-circumferential decompression technique for microsurgical en-bloc total ligamentum flavectomy with preservation of the facet joint to treat the patients who have a lumbar spinal stenosis with degenerative spondylolisthesis.

Methods

We retrospectively analyzed the clinical and radiologic outcomes of 19 patients who have a spinal stenosis with Meyerding grade I degenerative spondylolisthesis. They were treated using the "semi-circumferential decompression" method. We evaluated improvements in back and radiating pain using a visual analogue scale (VAS) and the Oswestry Disability Index (ODI). We also evaluated occurrence of spinal instability on radiological exam using percentage slip and slip angle.

Results

The mean VAS score for back pain decreased significantly from 6.3 to 4.3, although some patients had residual back pain. The mean VAS for radiating pain decreased significantly from 8.3 to 2.5. The ODI score improved significantly from 25.3 preoperatively to 10.8 postoperatively. No significant change in percentage slip was observed (10% preoperatively vs. 12.2% at the last follow-up). The dynamic percentage slip (gap in percentage slip between flexion and extension X-ray exams) did not change significantly (5.2% vs. 5.8%). Slip angle and dynamic slip angle did not change (3.2° and 8.2° vs. 3.6° and 9.2°, respectively).

Conclusions

The results suggested that semi-circumferential decompression is a clinically recommendable procedure that can improve pain. This procedure does not cause spinal instability when treating patients who have a spinal stenosis with degenerative spondylolisthesis.

Bilateral versus unilateral interlaminar approach for bilateral decompression in patients with single-level degenerative lumbar spinal stenosis: a multicenter retrospective study of 175 patients on postoperative pain, functional disability, and patient satisfaction

OBJECT

The bilateral and unilateral interlaminar techniques for bilateral decompression both demonstrate good results for the treatment of degenerative lumbar spinal stenosis (DLSS). Although there is some discussion about which approach is more effective, studies that directly compare these two popular techniques are rare. To address this shortcoming, this study compares postoperative functional disability, pain, and patient satisfaction among patients with single-level DLSS who underwent bilateral decompression using either a bilateral or unilateral approach.

METHODS

This retrospective study included patients who underwent operations between November 1, 2009, and October 1, 2011. These patients underwent single-level bilateral decompressive surgery using either the bilateral or unilateral interlaminar approach at one of 5 participating hospitals. Exclusion criteria included previous lumbar surgery, additional disc surgery, and spondylolisthesis requiring fusion surgery. Primary outcome measures included bodily pain (as reported using the visual analog scale [VAS]), the Roland-Morris Disability Questionnaire (RMDQ), and the Oswestry Disability Index (ODI). In addition, reductions in leg and back symptoms and the patient’s general evaluation of the procedure were queried. Finally, patient satisfaction and surgical parameters were evaluated. Questionnaires were sent to each patient’s home, and electronic patient files were used to collect the data.

RESULTS

One hundred and seventy-five patients returned the questionnaire (74.4% response rate; 68 and 107 patients who underwent the bilateral or unilateral approach, respectively). Mean age at surgery was 68 years (range 34–89 years), and the mean follow-up period was 14.2 months (range 3.3–27.4 years). There were no significant differences in ODI (20.3 vs 22.6 for the bilateral and unilateral approaches, respectively), RMDQ (3.99 vs 4.8, respectively), or pain scores between treatment groups. Back symptoms were reduced in 74.8% (bilateral: 74.6% vs unilateral: 75%; not significant), and leg symptoms in 80.6% of the patients (bilateral: 73.1% vs unilateral: 85.4%; p = 0.048). In total, 72.1% (bilateral) and 80.0% (unilateral) of patients reported good overall treatment results (p = 0.226). Significantly more patients in the unilateral group reported a better overall satisfaction with the procedure (82.1% vs 69.1%; p = 0.047).

CONCLUSIONS

There were no differences in postoperative functional disability and pain between the surgical techniques. The significant differences in patient satisfaction and reduction in leg symptoms were unrelated to surgical technique. The overall treatment results were satisfactory. Both techniques are safe and effective options for treating patients with single-level DLSS.

Bilateral Decompression via Microscopic TubularCrossing Laminotomy (MTCL) for Lumbar Spinal Stenosis: Technique and Early Surgical Result

The purpose of this study was to determine the feasibility and efficacy of bilateral decompression procedure via microscopic tubular crossing laminotomy (MTCL) for treating lumbar spinal stenosis (LSS). Seventeen patients with LSS underwent bilateral decompression via an MTCL procedure in which tubular retractor was placed. The mean age was 72 (range 59-84) years and there were 10 men and 7 women. All patients underwent pre- and postoperative dynamic lumbar x-ray, magnetic resonance (MR) image, and computed tomography. To verify the efficacy of this technique, pre- and postoperative cross-sectional area (CSA) of thecal sac, facet resection, and fatty infiltration (FI) of multifidus were measured. Clinical results were evaluated using Oswestry Disability Index (ODI), back and leg visual analog scale (VAS). The mean follow-up period was 17.5 months (range 12.1-21.2). 70.5% of MTCL was performed at the level of L4-5 and one case of dural violation (5.8%) was noted at the level of L5-S1. The mean preoperative CSA was 70.5 mm(2) (range 25.1-87.6) and it increased to 198.8 mm(2) (range 177.3-219.2) postoperatively (p = 0.00). The mean facet resection rate was 18.4% (range 9.9-26.9) and no radiological instability was noted postoperatively. MR image showed no increase in FI of the multifidus after 12 months of follow-up (p = 0.53). Preoperative clinical symptoms improved significantly at postoperative 6 months and 12 months of follow-up. These results indicate that an MTCL with use of tubular retractor system can be an effective procedure to achieve neural decompression for the treatment of LSS and it may be beneficial in preserving both facet joint and multifidus muscle.

Minimally invasive laminectomy for lumbar spinal stenosis in patients with and without preoperative spondylolisthesis: clinical outcome and reoperation rates

OBJECT

Surgical decompression is the intervention of choice for lumbar spinal stenosis (LSS) when nonoperative treatment has failed. Standard open laminectomy is an effective procedure, but minimally invasive laminectomy through tubular retractors is an alternative. The aim of this retrospective case series was to evaluate the clinical and radiographic outcomes of this procedure in patients who underwent LSS and to compare outcomes in patients with and without preoperative spondylolisthesis.

METHODS

Patients with LSS without spondylolisthesis and with stable Grade I spondylolisthesis who had undergone minimally invasive tubular laminectomy between 2004 and 2011 were included in this analysis. Demographic, perioperative, and radiographic data were collected. Clinical outcome was evaluated using the Oswestry Disability Index (ODI) and visual analog scale (VAS) scores, as well as Macnab's criteria.

RESULTS

Among 110 patients, preoperative spondylolisthesis at the level of spinal stenosis was present in 52.5%. At a mean follow-up of 28.8 months, scoring revealed a median improvement of 16% on the ODI, 2.75 on the VAS back, and 3 on the VAS leg, compared with the preoperative baseline (p < 0.0001). The reoperation rate requiring fusion at the same level was 3.5%. Patients with and without preoperative spondylolisthesis had no significant differences in their clinical outcome or reoperation rate.

CONCLUSIONS

Minimally invasive laminectomy is an effective procedure for the treatment of LSS. Reoperation rates for instability are lower than those reported after open laminectomy. Functional improvement is similar in patients with and without preoperative spondylolisthesis. This procedure can be an alternative to open laminectomy. Routine fusion may not be indicated in all patients with LSS and spondylolisthesis.

Degenerative lumbar spondylolisthesis: cohort of 670 patients, and proposal of a new classification

Degenerative spondylolisthesis is common in adults. No consensus is available about the analysis or surgical treatment of degenerative spondylolisthesis. In 2013, the French Society for Spine Surgery (Societe francaise de chirurgie du rachis) held a round table discussion to develop a classification system and assess the outcomes of the main surgical treatments. A multicentre study was conducted in nine centres located throughout France and Luxembourg. We established a database on a prospective cohort of 260 patients included between July 2011 and July 2012 and a retrospective cohort of 410 patients included in personal databases between 2009 and 2013. For patients in the prospective cohort clinical assessments were performed before and after surgery using the self-administered functional impact questionnaire AQS, SF12, and Oswestry Disability Index (ODI). Type of treatment and complications were recorded. Antero-posterior and lateral full-length radiographs were used to measure lumbar lordosis (LL), segmental lordosis (SL), pelvic incidence (PI), pelvic tilt (PT), sagittal vertical axis (SVA), and percentage of vertebral slippage. Mean follow-up was 10 months. We started a randomised clinical trial comparing posterior fusion of degenerative spondylolisthesis with versus without an inter-body cage. 60 patients were included, 30 underwent 180° fusion and 30 underwent 360° fusion using an inter-body cage implanted via a transforaminal approach. We evaluated the quality of neural decompression achieved by minimally invasive fusion technique. In a subgroup of 24 patients computed tomography (CT) was performed before and after the procedure and then compared. Mean age was 67 years and 73% of degenerative spondylolisthesis were located at L4-L5 level. The many surgical procedures performed in the prospective cohort were posterior fusion (39%), posterior fusion combined with inter-body fusion (36%), dynamic stabilization (15%), anterior lumbar fusion (8%), and postero-lateral fusion without exogenous material (2%). Peri-operative complications of any severity occurred in 17% of patients. The AQS, ODI and SF12 scores were improved significantly at follow-up. We found no differences in clinical improvements across surgical procedure types. Circumferential fusion (360°) was associated with greater relief of nerve root pain and better lordosis recovery after 1 year compared to postero-lateral fusion (180°). Post-operative CT images showed effective decompression of nervous structures after minimally invasive fusion. Longer follow-up of our patients is needed to assess the stability of the results of the various surgical procedures. Based on a radiological analysis, the authors propose a new classification with five types of degenerative spondylolisthesis: type 1, SL>5° and LL>PI-10°; type 2, SL<5° and LL>PI-10°; type 3, LL<PI-10°; type 4, LL<PI-10° and compensated sagittal balance with PT>25°; and type 5, sagittal imbalance with SVA>4 cm.

PROOF LEVEL

IV Observational cohort study. Retrospective review of prospectively collected outcome data.

Surgical management of lumbar degenerative spondylolisthesis

Lumbar degenerative spondylolisthesis (DS) is a common cause of low back pain, radiculopathy, and/or neurogenic claudication. Treatment begins with a trial of nonsurgical methods, including physical therapy, NSAIDs, and epidural corticosteroid injections. Surgical treatment with decompression and fusion is recommended for patients who do not respond to this initial regimen. Although much has been published in the past two decades on the surgical management of DS, the optimal method remains controversial. Interbody fusion may improve arthrodesis rates and can be performed via numerous surgical approaches. Minimally invasive techniques continue to be developed. Particular attention to surgical management of DS in the elderly is warranted given the increasing numbers of elderly persons. Healthcare utilization in the future must take into account evidence-based medicine that establishes clinically effective practices while simultaneously being cost effective.

Dynamic transpedicular stabilisation and decompression in single-level degenerative anterolisthesis and stenosis

BACKGROUND

Different treatment options exist for symptomatic single-level degenerative anterolisthesis and stenosis. While simple micro-decompression has been advocated lately, most authors recommend posterior decompression with fusion. In recent years, decompression and dynamic transpedicular stabilisation has been introduced for this indication. The aim of this study was to evaluate the safety and efficacy of decompression and dynamic transpedicular stabilisation with the Dynesys® system in single-level degenerative anterolisthesis and stenosis.

METHODS

Thirty consecutive patients with symptomatic single-level degenerative anterolisthesis and stenosis without scoliosis underwent decompression and single-level Dynesys stabilisation at the level of degenerative anterolisthesis. Patients were followed prospectively for 24 months with radiographs, Oswestry Disability Index scores, visual analogue scale (VAS) for back and leg pain, and estimated pain-free walking distance.

RESULTS

At the 2-year follow-up, back pain was reduced from 6.5 preoperatively to 2.5, leg pain from 5.4 to 0.6. The pain-free walking distance was estimated at 500 m preoperatively and at over 2 km after 2 years, while the ODI decreased from 54 % to 18 %. Screw loosening was found in 2/30 cases. Symptomatic adjacent segment disease was found in 3/30 patients between 12 and 24 months postoperatively.

CONCLUSIONS

Single-level Dynesys stabilisation combined with single- or multi-level decompression seems to be a safe and efficient treatment option in single-level degenerative anterolisthesis and stenosis over an observation period of 2 years, avoiding iliac crest or local bone grafting required by fusion procedures. However, it does not seem to avoid adjacent segment disease.

[Selective, microsurgical cross-over decompression of multisegmental degenerative lumbar spinal stenoses: the "Slalom" technique]

OBJECTIVE

Selective, bilateral multisegmental microsurgical decompression of lumbar spinal canal stenosis through separate, alternating cross-over approaches.

INDICATIONS

Two- and multisegmental degenerative central and lateral lumbar spinal stenoses.

CONTRAINDICATIONS

None (however, if stabilization is necessary, the Slalom technique is not possible).

SURGICAL TECHNIQUE

Minimally invasive, muscle-sparing and facet-joint-sparing bilateral decompression of the lumbar spinal canal through 2 or more alternating microsurgical cross-over approaches from one side.

POSTOPERATIVE MANAGEMENT

Early mobilization 4-6 h postoperatively. Soft lumbar brace for 4 weeks (optional).

RESULTS

Between December 2010 and May 2011, the operation was performed in 35 patients (10 women; 25 men; age 71.8 years). The average time of surgery was 42 min/segment, the average blood loss was 20.3 ml/segment. Of the 35 patients, 15 did not required wound drainage. All patients were mobilized without restriction after 4-6 h, hospitalization was 5.2 days. There were 3 intraoperative complications (2 Dura lesions [5.7%] and 1 temporary L5 radiculopathy probably due to swelling of the L5 nerve root [2.8%]). Postoperatively there was a significant improvement in quality of life as measured with EQ 5D and Oswestry Disability Index as well as a significant improvement of walking distance and standing time.

Minimum 3-year outcomes in patients with lumbar spinal stenosis after bilateral microdecompression by unilateral or bilateral laminotomy

Objective

Lumbar spine stenosis (LSS) can result in symptomatic compression of the neural elements, requiring surgical treatment if conservative management fails. Minimally invasive surgery has come to be more commonly used for the treatment of LSS. The current study describes outcomes of bilateral microdecompression by unilateral or bilateral laminotomy (BML) for degenerative LSS after a minimum follow-up period of 3 years and investigates factors that result in a poor outcome.

Methods

Twenty-one patients who were followed-up for at least 3 years were included in this study. For clinical evaluation, the Japanese Orthopedic Association (JOA) scoring system for low back pain was used. The modified grading system of Finneson and Cooper was used for outcome assessment. Radiographic evaluation was also performed for spondylolisthesis, sagittal rotation angle, and disc height.

Results

Twenty-one patients (10 men, 11 women) aged 53-82 years (64.1±8.9 years) were followed-up for a minimum of 3 years (36-69 months). During follow-up, two patients underwent reoperation. Average preoperative JOA score and clinical symptoms, except persistent low back pain, improved significantly at the latest follow-up. There were no significant differences in radiological findings preoperatively and postoperatively. Thirteen patients (61.9%) had excellent to fair outcomes.

Conclusion

BML resulted in a favorable and persistent outcome for patients with degenerative LSS without radiological instability over a mid-term follow-up period. Persistent low back pain unrelated to postoperative instability adversely affects mid-term outcomes.

Time spent per patient in lumbar spinal stenosis surgery

PURPOSE

To examine the time needed from a surgeon's viewpoint to treat a patient operated for lumbar spinal stenosis. We firstly aimed to give evidence of the wide ranging duration of standardized procedure. Secondly, we investigated factors affecting the time allocated to each patient.

METHODS

438 medical records of patients operated on for lumbar decompression without fusion (2005-2011) were retrospectively examined. Primary data were operative time (OT, min), length of stay (LoS, days) and number of postoperative visits. A fourth parameter was calculated, the time spent per patient (TSPP, min) by summing the time spent in surgery, during inpatient and outpatient follow-up visits. Factors that influenced these medical resources were examined.

RESULTS

Median (5th-95th percentile) LoS was 5 days (2-15), OT 106 min (60-194), number of medical visits 5 (2-11) and TSPP 329 min (206-533). In descending order, factors predicting LoS were age, no. of levels, sex, operative technique, cardiovascular risk index, dural tear and haematoma. Factors predicting OT were number of levels, dural tear, foraminotomy, synovial cyst and body mass index. The statistical model could predict 36% of the TSPP variance. We recommend that surgeons add 35 min for each level, 29 min for patients over 65 years, 30 min for women, 132 min for dural tear and 108 min for epidural haematoma.

CONCLUSION

TSPP treated for lumbar spinal stenosis is highly variable, yet partially predictable. These data may help individual surgeons or heads of departments to plan their activities.

Paradigm changes in spine surgery: evolution of minimally invasive techniques

Minimally invasive spine surgery (MISS) techniques were developed to address morbidities associated with open spinal surgery approaches. MISS was initially applied for indications such as the microendoscopic decompression of stenosis (MEDS)-an operation that has become widely implemented in modern spine surgery practice. Minimally invasive surgery for MEDS is an excellent example of how an MISS technique has improved outcomes compared with the use of traditional open surgical procedures. In parallel with reports of surgeon experience, accumulating clinical evidence suggests that MISS is favoured over open surgery, and one could argue that the role of MISS techniques will continue to expand. As the field of minimally invasive surgery has developed, MISS has been implemented for the treatment of increasingly difficult and complex pathologies, including trauma, spinal malignancies and spinal deformity in adults. In this Review, we present the accumulating evidence in support of minimally invasive techniques for established MISS indications, such as lumbar stenosis, and discuss the need for additional level I and level II data to demonstrate the benefit of MISS over traditional open surgery. The expanding utility of MISS techniques to address an increasingly broad range of spinal pathologies is also highlighted.