Degenerative spondylolisthesis does not affect the outcome of unilateral laminotomy with bilateral decompression in patients with lumbar stenosis

Comparison of Patients Operated for Lumbar Spinal Stenosis With and Without Spondylolisthesis​​​​​: A Secondary Analysis of the NORDSTEN Trials

STUDY DESIGN

Observational cohort study (secondary analysis of two randomized trials).

OBJECTIVE

The aim of this study was to investigate whether function, disability, pain, and quality of life before surgery and patient-reported outcome as well as complication and reoperation rates up to 2 years after surgery differ between lumbar spinal stenosis patients with and without spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Lumbar spinal stenosis is a degenerative condition of the spine, which appears with or without degenerative spondylolisthesis often presenting similar signs and symptoms.

MATERIALS AND METHODS

This study is a secondary analysis of two randomized trials on patients with lumbar spinal stenosis with and without spondylolisthesis conducted at 16 public Norwegian hospitals. Disability, function, back pain, leg pain, quality of life, complication, and reoperation rates up to 2 years after surgery were compared between the two cohorts.

RESULTS

A total of 704 patients were included in this study, 267 patients with spondylolisthesis [median age: 67.0 yr (IQR: 61.0-72.0 yr); 68.7% female] and 437 patients without spondylolisthesis [median age: 68.0 yr (IQR: 62.0-73.0 yr); 52.9% female]. In the linear mixed-model analysis there were no significant differences in disability, function, back pain, leg pain, and quality of life scores between the two cohorts of patient with and without spondylolisthesis before surgery or at 2 years of follow-up. The complication rate was 22.9% in patients with spondylolisthesis and 12.1% in patients without spondylolisthesis ( P <0.001). There were no significant differences in reoperation rates.

CONCLUSIONS

In patients with lumbar spinal stenosis the symptom burden before surgery and the clinical outcome up to 2 years after surgery were similar independently of a concomitant spondylolisthesis.

LEVEL OF EVIDENCE

II.

Clinical effectiveness of reduction and fusion versus in situ fusion in the management of degenerative lumbar spondylolisthesis: a systematic review and meta-analysis

PURPOSE

To compare the clinical effectiveness of reduction and fusion with in situ fusion in the management of patients with degenerative lumbar spondylolisthesis (DLS).

METHODS

The systematic review was conducted following the PRISMA guidelines. Relevant studies were identified from PubMed, Embase, Scopus, Cochrane Library, ClinicalTrials.gov, and Google Scholar. The inclusion criteria were: (1) comparative studies of reduction and fusion versus in situ fusion for DLS patients, (2) outcomes reported as VAS/NRS, ODI, JOA score, operating time, blood loss, complication rate, fusion rate, or reoperation rate, (3) randomized controlled trials and observational studies published in English from the inception of the databases to January 2023. The exclusion criteria included: (1) reviews, case series, case reports, letters, and conference reports, (2) in vitro biomechanical studies and computational modeling studies, (3) no report on study outcomes. The risk of bias 2 (RoB2) tool and the Newcastle-Ottawa scale was conducted to assess the risk of bias of RCTs and observational studies, respectively.

RESULTS

Five studies with a total of 704 patients were included (375 reduction and fusion, 329 in situ fusion). Operating time was significantly longer in the reduction and fusion group compared to in situ fusion group (weighted mean difference 7.20; 95% confidence interval 0.19, 14.21; P = 0.04). No additional significant intergroup differences were noted in terms of other outcomes analyzed.

CONCLUSION

While the reduction and fusion group demonstrated a statistically longer operating time compared to the in situ fusion group, the clinical significance of this difference was minimal. The findings suggest no substantial superiority of lumbar fusion with reduction over without reduction for the management of DLS.

Biomechanical response of decompression alone in lower grade lumbar degenerative spondylolisthesis--A finite element analysis

BACKGROUND

Previous studies have demonstrated the clinical efficacy of decompression alone in lower-grade spondylolisthesis. A higher rate of surgical revision and a lower rate of back pain relief was also observed. However, there is a lack of relevant biomechanical evidence after decompression alone for lower-grade spondylolisthesis.

PURPOSE

Evaluating the biomechanical characteristics of total laminectomy, hemilaminectomy, and facetectomy for lower-grade spondylolisthesis by analyzing the range of motion (ROM), intradiscal pressure (IDP), annulus fibrosus stress (AFS), facet joints contact force (FJCF), and isthmus stress (IS).

METHODS

Firstly, we utilized finite element tools to develop a normal lumbar model and subsequently constructed a spondylolisthesis model based on the normal model. We then performed total laminectomy, hemilaminectomy, and one-third facetectomy in the normal model and spondylolisthesis model, respectively. Finally, we analyzed parameters, such as ROM, IDP, AFS, FJCF, and IS, for all the models under the same concentrate force and moment.

RESULTS

The intact spondylolisthesis model showed a significant increase in the relative parameters, including ROM, AFS, FJCF, and IS, compared to the intact normal lumbar model. Hemilaminectomy and one-third facetectomy in both spondylolisthesis and normal lumbar models did not result in an obvious change in ROM, IDP, AFS, FJCF, and IS compared to the pre-operative state. Moreover, there was no significant difference in the degree of parameter changes between the spondylolisthesis and normal lumbar models after undergoing the same surgical procedures. However, total laminectomy significantly increased ROM, AFS, and IS and decreased the FJCF in both normal lumbar models and spondylolisthesis models.

CONCLUSION

Hemilaminectomy and one-third facetectomy did not have a significant impact on the segment stability of lower-grade spondylolisthesis; however, patients with LDS undergoing hemilaminectomy and one-third facetectomy may experience higher isthmus stress on the surgical side during rotation. In addition, total laminectomy changes the biomechanics in both normal lumbar models and spondylolisthesis models.

Preoperative factors affecting the two-year postoperative patient-reported outcome in single-level lumbar grade I degenerative spondylolisthesis

Background

The choice of operative method for lumbar spinal stenosis with Meyerding grade I degenerative spondylolisthesis remains controversial. The purpose of this study was to identify the preoperative factors affecting the 2-year postoperative patient-reported outcome in Meyerding grade I degenerative spondylolisthesis.

Methods

Seventy-two consecutive patients who had minimally invasive decompression alone (D group; 28) or with fusion (DF group; 44) were enrolled. The parameters investigated were the Japanese Orthopaedic Association back pain evaluation questionnaire as patient-reported assessment, and L4 slippage (L4S), lumbar lordosis (LL), and lumbar axis sacral distance (LASD) as an index of sagittal alignment for radiological evaluation. Data collected prospectively at 2 years postoperatively were examined by statistical analysis.

Results

Sixty-two cases (D group; 25, DF group; 37) were finally evaluated. In multiple logistic regression analysis, preoperative L4S and LASD were extracted as significant preoperative factors affecting the 2-year postoperative outcome. Patients with preoperative L4S of 6 mm or more have a lower rate of improvement in lumbar spine dysfunction due to low back pain (risk ratio=0.188, p=.043). Patients with a preoperative LASD of 30 mm or more have a higher rate of improvement in lumbar dysfunction due to low back pain (risk ratio=11.48, p=.021). The results of multiple logistic analysis by operative method showed that there was a higher rate of improvement in lumbar spine dysfunction due to low back pain in patients with preoperative LASD of 30 mm or more in DF group (risk ratio=172.028, p=.01).

Conclusions

Preoperative L4S and LASD were extracted as significant preoperative factors affecting patient-reported outcomes at 2 years postoperatively. Multiple logistic analyses by the operative method suggested that DF may be advantageous in improving lumbar dysfunction due to low back pain in patients with preoperative LASD of 30 mm or more.

Effect of Minimally Invasive Selective Laminectomy for Cervical Spondylotic Myelopathy on Degenerative Spondylolisthesis

STUDY DESIGN

Retrospective analysis of prospectively collected observational data.

OBJECTIVE

This study aimed to evaluate the slippage, sagittal alignment, and range of motion (ROM) after selective laminectomy (SL) in patients who had cervical spondylotic myelopathy (CSM) with degenerative spondylolisthesis (DS).

SUMMARY OF BACKGROUND DATA

Clinical outcomes have been reported for both decompression and fusion surgeries for DS of the lumbar spine. However, only a few reports have examined cervical spine spondylolisthesis.

MATERIALS AND METHODS

This study included 178 patients who underwent SL for CSM. Those with ossification of the posterior longitudinal ligament were excluded. Slippage >2 mm was defined as spondylolisthesis, and spondylolisthesis progression was defined as an additional displacement >2 mm on a neutral radiograph. The slippage, translational motion, C2-C7 angle, local kyphosis, and ROM were examined before and ≥2 years after surgery. Radiologic parameters were evaluated according to the slip direction and the number of laminae removed.

RESULTS

DS was observed in 29 patients (16.3%); 24 patients, comprising 9 and 15 in the anterolisthesis and retrolisthesis groups, respectively, were successfully followed up for more than 2 years. Preoperative and postoperative radiologic changes in slippage, translational motion, C2-C7 angle, local kyphosis, and ROM were not remarkable in either group regardless of the number of laminae removed. Revision surgery for the progression of DS and alignment deterioration was not required in any patient of either group.

CONCLUSIONS

SL does not affect DS, sagittal alignment, or ROM irrespective of the slip direction and the number of laminae removed, even after >2 years after surgery. Given the preservation of the posterior elements, SL may be an effective treatment for CSM with DS.

LEVEL OF EVIDENCE

Level IV.

Clinical Outcomes of Minimally Invasive Posterior Decompression for Lumbar Spinal Stenosis with Degenerative Spondylolisthesis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To compare the clinical outcomes 5 years after minimally invasive posterior decompression for lumber spinal stenosis (LSS) between patients with and without degenerative spondylolisthesis (DS).

SUMMARY OF BACKGROUND DATA

Indications for surgical procedures for patients with LSS and DS are still under investigation. Since minimally invasive surgery does not affect most anatomical structures, preoperative DS may not negatively affect the clinical outcomes of minimally invasive posterior decompression.

METHODS

Overall, 198 patients with LSS who underwent microendoscopic or microscopic decompression and were followed up for more than 5 years postoperatively were included in the present study. Patients who showed a segmental kyphosis >5° at the surgical level during flexion were treated with fusion surgery. However, other patients, including those with DS, were treated with posterior decompression. The patients were divided into two groups: the DS group included 82 patients with >3-mm slip and the non-DS group included 112 patients with ≤3-mm slip or without slip. A mixed-effects model adjusted for age and sex was used to compare the improvements in the visual analog scale score for low-back pain and the Japanese Orthopaedic Association score of the two groups. For subgroup analysis (n = 53), the changes in the preoperative physical component summary and the mental component summary of Short Form-36 of the two groups at 5 years after surgery were evaluated.

RESULTS

There was no significant difference in the improvement of preoperative low-back pain visual analog scale score and Japanese Orthopaedic Association score 5 years after surgery between the two groups. Subgroup analysis showed no significant difference between the two groups in the improvement of preoperative physical component summary and mental component summary 5 years after surgery.

CONCLUSION

After carefully eliminating patients with segmental instability, DS did not affect the clinical outcomes of minimally invasive decompression surgery.Level of Evidence: 3.

Management of degenerative spondylolisthesis: development of appropriate use criteria

BACKGROUND CONTEXT

Outcomes of treatment in care of patients with spinal disorders are directly related to patient selection and treatment indications. However, for many disorders, there is absence of consensus for precise indications. With the increasing emphasis on quality and value in spine care, it is essential that treatment recommendations and decisions are optimized.

PURPOSE

The purpose of the North American Spine Society Appropriate Use Criteria was to determine the appropriate (ie reasonable) multidisciplinary treatment recommendations for patients with degenerative spondylolisthesis across a spectrum of more common clinical scenarios.

STUDY DESIGN

A Modified Delphi process was used.

METHODS

The methodology was based on the Appropriate Use Criteria development process established by the Research AND Development Corporation. The topic of degenerative spondylolisthesis was selected by the committee, key modifiers determined, and consensus reached on standard definitions. A literature search and evidence analysis were completed by one work group simultaneously as scenarios were written, reviewed, and finalized by another work group. A separate multidisciplinary rating group was assembled. Based on the literature, provider experience, and group discussion, each scenario was scored on a nine-point scale on two separate occasions, once without discussion and then a second time following discussion based on the initial responses. The median rating for each scenario was then used to determine if indications were rarely appropriate (1 - 3), uncertain (4-6), or appropriate (7-9). Consensus was not mandatory.

RESULTS

There were 131 discrete scenarios. These addressed questions on bone grafting, imaging, mechanical instability, radiculopathy with or without neurological deficits, obesity, and yellow flags consisting of psychosocial and medical comorbidities. For most of these, appropriateness was established for physical therapy, injections, and various forms of surgical intervention. The diagnosis of spondylolisthesis should be determined by an upright x-ray. Scenarios pertaining to bone grafting suggested that patients should quit smoking prior to surgery, and that use of BMP should be reserved for patients who had risk factors for non-union. Across all clinical scenarios, physical therapy (PT) had an adjusted mean of 7.66, epidural steroid injections 5.76, and surgery 4.52. Physical therapy was appropriate in most scenarios, and most appropriate in patients with back pain and no neurological deficits. Epidural steroid injections were most appropriate in patients with radiculopathy. Surgery was generally more appropriate for patients with neurological deficits, higher disability scores, and dynamic spondylolisthesis. Mechanical back pain and presence of yellow flags tended to be less appropriate, and obesity in general had relatively little influence on decision making. Decompression alone was more strongly considered in the presence of static versus dynamic spondylolisthesis. On average, posterior fusion with or without interbody fusion was similarly appropriate, and generally more appropriate than stand-alone interbody fusion which was in turn more appropriate than interspinous spacers.

CONCLUSIONS

Multidisciplinary appropriate treatment criteria were generated based on the Research AND Development methodology. While there were consistent and significant differences between surgeons and non-surgeons, these differences were generally very small. This document provides comprehensive evidence-based recommendations for evaluation and treatment of degenerative spondylolisthesis. The document in its entirety will be found on the North American Spine Society website (https://www.spine.org/Research-Clinical-Care/Quality-Improvement/Appropriate-Use-Criteria).

Variation in surgical treatment of degenerative spondylolisthesis in Canada: surgeon assessment of stability and impact on treatment

INTRODUCTION

Controversy exists regarding the optimal surgical treatment of degenerative lumbar spondylolisthesis (DS). Not all DS patients are the same, and the degree to which inherent stability may dictate treatment is unknown. The purpose of this study was to determine the variability in surgical approach relative to surgeon classified stability. The secondary objective was to compare patient-reported outcomes (PROs) across different surgical techniques and grades of stability.

METHODS

Patients prospectively enrolled from eleven tertiary care institutions and followed from 2015 to 2019. The surgical technique was at the surgeon's discretion. Surgeons were asked to grade the degree of instability based on the degenerative spondylolisthesis instability classification system (DSIC). DSIC categorizes three different types (I-stable, II-potentially unstable, and III-unstable). One-year changes in PROs were compared between each group. Multivariable regression was used to identify any characteristics that explained variability in treatment.

RESULTS

There were 323 patients enrolled in this study. Surgeons' stability classification versus procedure [decompression alone (D)/decompression and posterolateral fusion (D-PL)/and decompression with posterior/transforaminal lumbar interbody fusion (D-PLIF/TLIF)] were as follows: type I (n = 91): D-41%/D-PL-13%/D-PLIF/TLIF-46%; type II (n = 175): D-23%/D-PL-17%/D-PLIF/TLIF-60%; and type III (n = 57):(D-0%/D-PL-14%/D-PLIF/TLIF-86%). Type I patients undergoing D-PL had some improvements in EQ-5D and NRS versus those undergoing D-PLIF/TLIF but otherwise there were no other significant differences between groups. Regression analysis demonstrated advanced age (OR = 1.06, CI 1.02-10.12) and type I (OR = 2.61, CI 1.17-5.81) were associated with receiving decompression surgery alone.

CONCLUSIONS

There exists considerable variation in surgical management of DS in Canada. Given similar PROs in two of the three groups, there is potential to tailor surgical intervention and improve resource utilization.

Comparison of SDSG and CARDS classifications for L5/S1 lumbar degenerative spondylolisthesis: an independent inter- and intra-observer agreement study

BACKGROUND

Lumbar degenerative spondylolisthesis (DS) has been a common disease that makes increasing patients to suffer from different degrees of low back pain and radicular symptoms. The Spinal Deformity Study Group (SDSG) and the Clinical and Radiographic Degenerative Spondylolisthesis (CARDS) systems are commonly used to classify the disease, and help to make a more detailed treatment plan. The objective of this study is to compare the reliability and reproducibility of SDSG and CARDS classifications, and to explore their clinical application value.

METHODS/DESIGN

All 117 patients with L5/S1 lumbar DS were enrolled. Five experienced spine surgeons were selected to assess DS with SDSG and CARDS systems. Kappa (K) value was used to check the coefficient consistency for multi-factor and assess the inter- and intra-observer agreement. After 12 weeks, the analysis was repeated.

RESULTS

The inter-observer reliability and intra-observer reproducibility of SDSG system were substantial with K values of 0.704 and 0.861, while those of CARDS system were substantial with values of 0.620 and 0.878.

CONCLUSION

SDSG system had better inter-observer reliability in comparison with CARDS system, and though CARDS system is more intuitive and simpler, it is more likely to produce deviations when using it. Both SDSG and CARDS systems show substantial agreement and have great significance in surgical strategy of L5/S1 lumbar DS, they can be widely used in clinical practice.

Lumbar degenerative spondylolisthesis: factors associated with the decision to fuse

BACKGROUND CONTEXT

The indication to perform a fusion and decompression surgery as opposed to decompression alone for lumbar degenerative spondylolisthesis (LDS) remains controversial. A variety of factors are considered when deciding on whether to fuse, including patient demographics, radiographic parameters, and symptom presentation. Likely surgeon preference has an important influence as well.

PURPOSE

The aim of this study was to assess factors associated with the decision of a Canadian academic spine surgeon to perform a fusion for LDS.

STUDY DESIGN/SETTING

This study is a retrospective analysis of patients prospectively enrolled in a multicenter Canadian study that was designed to evaluate the assessment and surgical management of LDS.

PATIENT SAMPLE

Inclusion criteria were patients with: radiographic evidence of LDS and neurogenic claudication or radicular pain, undergoing posterior decompression alone or posterior decompression and fusion, performed in one of seven, participating academic centers from 2015 to 2019.

OUTCOME MEASURES

Patient demographics, patient-rated outcome measures (Oswestry Disability Index [ODI], numberical rating scale back pain and leg pain, SF-12), and imaging parameters were recorded in the Canadian Spine Outcomes Research Network (CSORN) database. Surgeon factors were retrieved by survey of each participating surgeon and then linked to their specific patients within the database.

METHODS

Univariate analysis was used to compare patient characteristics, imaging measures, and surgeon variables between those that had a fusion and those that had decompression alone. Multivariate backward logistic regression was used to identify the best combination of factors associated with the decision to perform a fusion.

RESULTS

This study includes 241 consecutively enrolled patients receiving surgery from 11 surgeons at 7 sites. Patients that had a fusion were younger (65.3±8.3 vs. 68.6±9.7 years, p=.012), had worse ODI scores (45.9±14.7 vs. 40.2±13.5, p=.007), a smaller average disc height (6.1±2.7 vs. 8.0±7.3 mm, p=.005), were more likely to have grade II spondylolisthesis (31% vs. 14%, p=.008), facet distraction (34% vs. 60%, p=.034), and a nonlordotic disc angle (26% vs. 17%, p=.038). The rate of fusion varied by individual surgeon and practice location (p<.001, respectively). Surgeons that were fellowship trained in Canada more frequently fused than those who fellowship trained outside of Canada (76% vs. 57%, p=.027). Surgeons on salary fused more frequently than surgeons remunerated by fee-for-service (80% vs. 64%, p=.004). In the multivariate analysis the clinical factors associated with an increased odds of fusion were decreasing age, decreasing disc height, and increasing ODI score; the radiographic factors were grade II spondylolisthesis and neutral or kyphotic standing disc type; and the surgeon factors were fellowship location, renumeration type and practice region. The odds of having a fusion surgery was more than two times greater for patients with a grade II spondylolisthesis or neutral and/or kyphotic standing disc type (opposed to lordotic standing disc type). Patients whose surgeon completed their fellowship in Canada, or whose surgeon was salaried (opposed to fee-for-service), or whose surgeon practiced in western Canada had twice the odds of having fusion surgery.

CONCLUSIONS

The decision to perform a fusion in addition to decompression for LDS is multifactorial. Although patient and radiographic parameters are important in the decision-making process, multiple surgeon factors are associated with the preference of a Canadian spine surgeon to perform a fusion for LDS. Future work is necessary to decrease treatment variability between surgeons and help facilitate the implementation of evidence-based decision making.

Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression for Lumbar Spinal Stenosis Provides Comparable Clinical Outcomes in Patients with and without Degenerative Spondylolisthesis

OBJECTIVE

To investigate and compare the clinical and radiological outcomes of lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD) for lumbar spinal stenosis (LSS) patients with and without degenerative spondylolisthesis (DS).

METHODS

A total of 129 patients who underwent LE-ULBD for single-level LSS were retrospectively reviewed. The patients were classified into 2 groups based on the presence of DS. Clinical outcomes were assessed with the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire and numeric rating scale (NRS) for low back pain, lower limb pain, and lower limb numbness. Scores were obtained at baseline and final follow-up (mean follow-up, 28.6 months [range, 24-63 months]).

RESULTS

The follow-up rate was 77.5% (103 patients). All domains of the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire and NRS evaluations significantly improved during the follow-up period in both groups; group differences were not significant except for the postoperative NRS limb numbness score, which was higher in patients with DS. The Macnab outcome classification was excellent or good in 80% of patients without DS and 77.1% of patients with DS. During the follow-up period, the increase of vertebral slip was observed in 31% of the patients with DS that includes vertebral slip progression defined as percent slip >5% in 4% of the patients. The increase of vertebral slip was not related to a clinical outcome. Segmental motion of the affected intervertebral disc did not increase after surgery.

CONCLUSIONS

LE-ULBD provides a comparably favorable outcome in LSS patients with and without DS. Postoperative segmental instability did not occur in patients with DS.

Long-Term Outcomes Following Lumbar Microendoscopic Decompression for Lumbar Spinal Stenosis with and without Degenerative Spondylolisthesis: Minimum 10-Year Follow-Up

OBJECTIVE

To determine whether preoperative presence of degenerative lumbar spondylolisthesis (DS) worsens the minimum 10-year outcome of patients undergoing microendoscopic decompression (MED) for lumbar spinal stenosis (SS).

METHODS

Eighty patients undergoing MED were classified into 2 groups: DS group (34 SS with DS patients) and SS group (46 SS without DS patients). The degrees of improvement (DOIs) by the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and intensities of improvement (IOIs) by Visual Analog Scale (VAS) at 120-159 (mean, 138.4) months after MED of the DS and SS groups were statistically compared. Patients with DS were classified into 2 groups based on the effectiveness by VAS or JOABPEQ: effective group (E group: IOI or DOI ≥20) and ineffective group (I group). All preoperative radiologic measurements were statistically compared between the E and I groups.

RESULTS

Significant decreases in low back pain, leg pain, and numbness, as measured by VAS, were noted at follow-up in the DS and SS groups. The effectiveness rates of pain-related disorders, lumbar spine dysfunction, and gait disturbance by JOABPEQ were almost equally high in the DS and SS groups. Statistical comparisons of the DOIs in all 5 functional scores and IOIs in low back pain, leg pain, and numbness showed no significant differences between the DS and SS groups. No significant differences were confirmed between the E and I groups concerning preoperative spondylolisthesis and instability.

CONCLUSIONS

Our study indicated that preoperative DS did not worsen the outcome of patients with SS undergoing MED.

The effect of preoperative degenerative spondylolisthesis on postoperative outcomes of degenerative lumbar spinal stenosis: A single-center cohort study protocol

BACKGROUND

Most degenerative lumbar spinal stenosis (DLSS) patients primitively received the conservative treatment to control symptoms. In order to develop an optimal surgical treatment strategy, it is very significant to understand how the degenerative lumbar spondylolisthesis (DS) affects the effect of decompression in the DLSS. Thus, the aim of this current study was to explore whether the concomitant DS would affect the effect of decompression alone in the patients with DLSS.

METHODS

The current study was carried out at our hospital and it was approved through our institutional review committee of General Hospital of Ningxia Medical University. During the period from January 2015 to December 2017, in our study, we identified consecutive patients who received the minimally invasive laminectomy to treat the DLSS. The inclusion criterion included radicular leg pain or neurogenic claudication with the neurological symptoms associated with DLSS syndrome, magnetic resonance imaging of the lumbar spine reveals at least 1 level of serious stenosis, the conservative treatment failed for at least 3 months, and patients agreed to provide the postoperative details. The major outcomes of this present research was Oswestry Disability Index. Secondary outcomes of this current study involved visual analog score, short form-36, surgical revision rate as well as complications.

RESULTS

We assumed that previous DS possessed a negative effect on the postoperative results of the DLSS patients.

TRIAL REGISTRATION

researchregistry5943.

Comparative Effectiveness of Microdecompression Alone vs Decompression Plus Instrumented Fusion in Lumbar Degenerative Spondylolisthesis

IMPORTANCE

Conflicting evidence and large practice variation are present in the surgical treatment of degenerative spondylolisthesis. More than 90% of surgical procedures in the United States include instrumented fusion compared with 50% or less in other countries.

OBJECTIVE

To evaluate whether the effectiveness of microdecompression alone is noninferior to decompression with instrumented fusion in a real-world setting.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter comparative effectiveness study with a noninferiority design assessed prospective data from the Norwegian Registry for Spine Surgery. From September 19, 2007, to December 21, 2015, 1376 patients at 35 Norwegian orthopedic and neurosurgical departments underwent surgery for lumbar spinal stenosis with degenerative spondylolisthesis without scoliosis. After excluding patients undergoing laminectomy alone, fusion without instrumentation, or surgery in more than 2 levels and those with a former operation at the index level, 794 patients were included in the analyses, regardless of missing or incomplete follow-up data, before propensity score matching. Data were analyzed from March 20 to October 30, 2018.

EXPOSURES

Microdecompression alone or decompression with instrumented fusion.

MAIN OUTCOMES AND MEASURES

A reduction from baseline of 30% or greater in the Oswestry Disability Index at 12-month follow-up.

RESULTS

After propensity score matching, 570 patients (413 female [72%]; mean [SD] age, 64.7 [9.5] years) were included for comparison, with 285 undergoing microdecompression (mean [SD] age, 64.6 [9.8] years; 205 female [72%]) and 285 undergoing decompression with instrumented fusion (mean [SD] age, 64.8 [9.2] years; 208 female [73%]). The proportion of each type of procedure varied between departments. However, changes in outcome scores varied within patients but not between departments. The proportion of patients with improvement in the Oswestry Disability Index of at least 30% was 150 of 219 (68%) in the microdecompression group and 155 of 215 (72%) in the instrumentation group. The 95% CI (-12% to 5%) for the difference of -4% was above the predefined margin of noninferiority (-15%). Microdecompression alone was associated with shorter operation time (mean [SD], 89 [44] vs 180 [65] minutes; P < .001) and shorter hospital stay (mean [SD], 2.5 [2.4] vs 6.4 [3.0] days; P < .001).

CONCLUSIONS AND RELEVANCE

Among patients with degenerative spondylolisthesis, the clinical effectiveness of microdecompression alone was noninferior to that of decompression with instrumented fusion. Microdecompression alone was also associated with shorter durations of surgery and hospital stay, supporting the suggestion that the less invasive procedure should be considered for most patients.

Preliminary Results on Radiological Hypermobility at Upper Adjacent Disc Level in Posterior Lumbar Interbody Fusion Compared to Advanced Dynamic Stabilization

Whether posterior lumbar interbody fusion (PLIF) is effective in patients older than 55 years remains questionable because of the high prevalence of adjacent segment disease. We retrospectively investigated early clinical outcomes and radiological changes at upper adjacent disc (UAD) level in such age-group patients who underwent advanced dynamic stabilization (ADS) or PLIF. ADS or PLIF were performed in patients with grade 1 spondylolisthesis or disc degeneration complicated by apparent vacuum phenomenon. All patients suffered from neurological symptoms in lower limbs with/without low back pain. In all, 16 patients (six females; mean age, 69.0 ± 8.5 years) who underwent ADS and 14 patients (seven females; mean age, 67.8 ± 9.3 years) who underwent PLIF were followed-up, and preoperative and postoperative final disc height (DH) and range of motion (ROM) were investigated retrospectively using dynamic radiography at the operated and UAD levels. Clinical data of patients who underwent ADS and PLIF were as follows: postoperative follow-up, 459.3 ± 263.5 and 507.7 ± 288.3 days; preoperative Japanese Orthopaedic Association (JOA) score, 14.4 ± 4.1 and 13.4 ± 4.5; and recovery rate of JOA score, 67.5 ± 18.5 and 50.1 ± 23.4%, respectively. Recovery rate of JOA score in ADS group was significantly high compared to PLIF group (P = 0.044). At UAD level, ROM decreased from 4.7 ± 2.9° preoperatively to 3.6 ± 2.6° postoperatively in the ADS group and increased from 3.4 ± 4.1° preoperatively to 5.6 ± 2.8° postoperatively with significant hypermobility (P = 0.020) in the PLIF group. ADS has the advantage in clinical outcomes even in the postoperative early stage, avoiding the early hypermobility at UAD level, compared to PLIF in patients older than 55 years.

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.

Surgical Outcome of Decompression and Fixation of Degenerative Lumbosacral Spondylolisthesis Surgery in Pakistani Population

Background

Spondylolisthesis is characterized by the slipping of one vertebra, compared with the underlying one, due to structural and degenerative changes. Its origin is multifactorial which includes disc degeneration, facet joint anatomic orientation, iliolumbar configuration, and ligament hyperlaxity. The most common operative treatment is decompression and may require an individualized surgical plan. However, only decompression may progress the slippage which can result in pain or recurrence of neurological complaints. Therefore, lumbar fusion and fixation are considered appropriate to stabilise the spine and prevent delayed deterioration. The aim of our study was to find out the outcome of posterior decompression, with reduction and fixation of lumbosacral spondylolisthesis by Oswestry Disability Index (ODI) to improve further our results.

Methods

This study was conducted from July 2013 to February 2017 including 94 patients with lumbosacral spondylolisthesis. The Meyerding classification was used to grade the extent of vertebral slippage. The assessment was done using the ODI.

Results

There were 50 (53.19%) males and 54 (46.80%) females with a mean age of 44 years ± 10.49 SD. Backache was present in all patients and claudication in 85 (90.42%) patients. There were 10 (10.63%) patients with spondylolisthesis at L3-L4, 36 (38.29%) at L5-S1 and 48 patients (51.06%) at L4-L5 level. In 48 patients with L4-L5 level, 38 (79.16%) were in grade II while six (12.5%) were in grade III. According to the preoperative ODI score, 38 patients were placed in moderate disability, 42 patients were severely disabled while four patients were disabled.

Good outcome was achieved in a total of 79 (84.04%) patients. In 40 (42.55%) patients, with complete reduction, the good outcome achieved in 35 (83.33%) while in 22 (23.40%) patients there was no reduction and a good outcome was achieved in 17 (77.27%) patients. In 38 (40.42%) patients with moderate disability, 32 (84.04%) patients had a good outcome. Post-operative cerebrospinal fluid (CSF) leak occurred in five (5.31%) and wound infection in seven (7.44%) patients while there was no mortality.

Conclusion

Reduction with decompression can have a good outcome in spondylolisthesis, and ODI should be used as a predictor of outcome. It also shows that proper decompression is required and not a complete reduction.

Comparison of bilateral decompression via unilateral laminotomy and conventional laminectomy for single-level degenerative lumbar spinal stenosis regarding low back pain, functional outcome, and quality of life - A Randomized Controlled, Prospective Trial

Background

Conventional posterior open lumbar surgery is associated with considerable trauma to the paraspinal muscles. Severe damage to the paraspinal muscles could cause low back pain (LBP), resulting in poor functional outcomes. Thus, several studies have proposed numerous surgical techniques that can minimize damage to the paraspinal muscles, particularly unilateral laminotomy for bilateral decompression. The purpose of this study is to compare the degree of postoperative LBP, functional outcome, and quality of life of patients between bilateral decompression via unilateral laminotomy (BDUL; group U) and conventional laminectomy (CL; group C).

Methods

Of 87 patients who underwent diagnostic and decompression surgery, 50 patients who met the inclusion and exclusion criteria and were followed up for > 2 years were enrolled. The patients were asked to record their visual analog scale pain score after 6, 12, and 24 months postoperatively. BDUL was used for group U, whereas CL was used for group C. The patients were randomly divided based on one of the two techniques, and they were followed up for over 2 years. Functional outcomes were assessed by the Oswestry Disability Index (ODI), Roland–Morris Disability Questionnaire (RMDQ), and SF-36.

Results

Operation time was significantly shorter in group U than in group C (p = 0.003). At 6, 12, and 24 months, there was no significant difference between the two groups in terms of spine-related pain (all p > 0.05). Functional outcomes using ODI and RMDQ and quality of life using SF-36 were not significantly different between the groups (all p > 0.05).

Conclusions

Regarding single-level decompression for degenerative lumbar spinal stenosis, group U had the advantages of shorter operation time than group C, but not in terms of back pain, functional outcome, and quality of life.

Outcome of unilateral versus standard open midline approach for bilateral decompression in lumbar spinal stenosis: is "over the top" really better? A Swiss prospective multicenter cohort study

OBJECTIVE

In this retrospective analysis of a prospective multicenter cohort study, the authors assessed which surgical approach, 1) the unilateral laminotomy with bilateral spinal canal decompression (ULBD; also called "over the top") or 2) the standard open bilateral decompression (SOBD), achieves better clinical outcomes in the long-term follow-up. The optimal surgical approach (ULBD vs SOBD) to treat lumbar spinal stenosis remains controversial.

METHODS

The main outcomes of this study were changes in a spinal stenosis measure (SSM) symptoms score, SSM function score, and quality of life (sum score of the 3-level version of the EQ-5D tool [EQ-5D-3L]) over time. These outcome parameters were measured at baseline and at 12-, 24-, and 36-month follow-ups. To obtain an unbiased result on the effect of ULBD compared to SOBD the authors used matching techniques relying on propensity scores. The latter were calculated based on a logistic regression model including relevant confounders. Additional outcomes of interest were raw changes in main outcomes and in the Roland and Morris Disability Questionnaire from baseline to 12, 24, and 36 months.

RESULTS

For this study, 277 patients met the inclusion criteria. One hundred forty-nine patients were treated by ULBD, and 128 were treated by SOBD. After propensity score matching, 128 patients were left in each group. In the matched cohort, the mean (95% CI) estimated differences between ULBD and SOBD for change in SSM symptoms score from baseline to 12 months were -0.04 (-0.25 to 0.17), to 24 months -0.07 (-0.29 to 0.15), and to 36 months -0.04 (-0.28 to 0.21). For change in SSM function score, the estimated differences from baseline to 12 months were 0.06 (-0.08 to 0.21), to 24 months 0.08 (-0.07 to 0.22), and to 36 months 0.01 (-0.16 to 0.17). Differences in changes between groups in EQ-5D-3L sum scores were estimated to be -0.32 (-4.04 to 3.40), -0.89 (-4.76 to 2.98), and -2.71 (-7.16 to 1.74) from baseline to 12, 24, and 36 months, respectively. None of the group differences between ULBD and SOBD were statistically significant.

CONCLUSIONS

Both surgical techniques, ULBD and SOBD, may provide effective treatment options for DLSS patients. The authors further determined that the patient outcome results for the technically more challenging ULBD seem not to be superior to those for the SOBD even after 3 years of follow-up.

Decreased estimated blood loss in lateral trans-psoas versus anterior approach to lumbar interbody fusion for degenerative spondylolisthesis

Background

The goal of the current study was to compare the perioperative and post-operative outcomes of eXtreme lateral trans-psoas approach (XLIF) versus anterior lumbar interbody fusion (ALIF) for single level degenerative spondylolisthesis. The ideal approach for degenerative spondylolisthesis remains controversial.

Methods

Consecutive patients undergoing single level XLIF (n=21) or ALIF (n=54) for L4-5 degenerative spondylolisthesis between 2008-2012 from a single academic center were retrospectively reviewed. Groups were compared for peri-operative data (estimated blood loss, operative time, adjunct procedures or additional implants), radiographic measurements (L1-S1 cobb angle, disc height, fusion grade, subsidence), 30-day complications (infection, DVT/PE, weakness/paresthesia, etc.), and patient reported outcomes (leg and back Numerical Rating Scale, and Oswestry Disability Index).

Results

Estimated blood loss was significantly lower for XLIF [median 100; interquartile range (IQR), 50-100 mL] than for ALIF (median 250; IQR, 150-400 mL; P<0.001), including after adjusting for significantly higher rates of posterior decompression in the ALIF group. There were no significant differences in rates of complications within 30 days, radiographic outcomes, or in re-operation rates. Both groups experienced significant pain relief post-operatively.

Conclusions

The lateral trans-psoas approach is associated with diminished blood loss compared to the anterior approach in the treatment of degenerative spondylolisthesis. We were unable to detect differences in radiographic outcomes, complication rates, or patient reported outcomes. Continued efforts to directly compare approaches for specific indications will minimize complications and improve outcomes. Further studies will continue to define indications for lateral versus anterior approach to lumbar spine for degenerative spondylolisthesis.

Upright MRI after decompression of spinal stenosis and concurrent spondylolisthesis

OBJECTIVEThe treatment of patients with spinal stenosis and concurrent degenerative spondylolisthesis is controversial. Two large randomized controlled clinical trials reported contradictory results. The authors hypothesized that a substantial number of patients will show evidence of micro-instability after a sole decompression procedure.METHODSThis study was a retrospective analysis of all cases of lumbar spinal stenosis treated at the Frankfurt University Clinic (Universitätsklinik Frankfurt) from 2010 through 2013. Patients who had associated spondylolisthesis underwent upright MRI studies in flexion and extension for identification of subtle signs of micro-instability. Clinical outcome was assessed by means of SF-36 bodily pain (BP) and physical functioning (PF) scales.RESULTSA total of 21 patients were recruited to undergo upright MRI studies. The mean duration of follow-up was 65 months (SD 16 months). Of these 21 patients, 10 (47%) showed signs of micro-instability as defined by movement of > 4 mm on flexion/extension MRI. Comparison of mean SF-36 BP and PF scores in the group of patients who showed micro-instability versus those who did not showed no statistically significant difference on either scale.CONCLUSIONSThere seems to be a substantial subset of patients who develop morphological micro-instability after sole decompression procedures but do not experience any clinically significant effect of the instability.

Minimally Invasive Approaches for Surgical Treatment of Lumbar Spondylolisthesis

The unilateral laminotomy for bilateral decompression initially was described in the late 1990s and has evolved in conjunction with minimally invasive surgical instrumentation. This technique has been shown to significantly improve bilateral symptoms regardless of the side of approach. It also can be used for multilevel decompressions using the slalom technique with alternating lateralizing sites of access. The over-the-top technique involving a unilateral approach for bilateral decompression helps preserve the posterior tension band and can accomplish the operative goals with better clinical outcomes than traditional open approaches.

Decompression alone versus decompression with instrumental fusion the NORDSTEN degenerative spondylolisthesis trial (NORDSTEN-DS); study protocol for a randomized controlled trial

BACKGROUND

Fusion in addition to decompression has become the standard treatment for lumbar spinal stenosis with degenerative spondylolisthesis (DS). The evidence for performing fusion among these patients is conflicting and there is a need for further investigation through studies of high quality. The present protocol describes an ongoing study with the primary aim of comparing the outcome between decompression alone and decompression with instrumented fusion. The secondary aim is to investigate whether predictors can be used to choose the best treatment for an individual. The trial, named the NORDSTEN-DS trial, is one of three studies in the Norwegian Degenerative Spinal Stenosis (NORDSTEN) study.

METHODS

The NORDSTEN-DS trial is a block-randomized, controlled, multicenter, non-inferiority study with two parallel groups. The surgeons at the 15 participating hospitals decide whether a patient is eligible or not according to the inclusion and exclusion criteria. Participating patients are randomized to either a midline preserving decompression or a decompression followed by an instrumental fusion. Primary endpoint is the percentage of patients with an improvement in Oswestry Disability Index version 2.0 of more than 30% from baseline to 2-year follow-up. Secondary outcome measurements are the Zürich Claudication Questionnaire, Numeric Rating Scale for back and leg pain, Euroqol 5 dimensions questionnaire, Global perceived effect scale, complications and several radiological parameters. Analysis and interpretation of results will also be conducted after 5 and 10 years.

CONCLUSION

The NORDSTEN/DS trial has the potential to provide Level 1 evidence of whether decompression alone should be advocated as the preferred method or not. Further on the study will investigate whether predictors exist and if they can be used to make the appropriate choice for surgical treatment for this patient group.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02051374 . First Posted: January 31, 2014. Last Update Posted: February 14, 2018.

Does Concomitant Degenerative Spondylolisthesis Influence the Outcome of Decompression Alone in Degenerative Lumbar Spinal Stenosis? A Meta-Analysis of Comparative Studies

OBJECTIVE

To investigate whether the preoperative presence of degenerative spondylolisthesis (DS) worsens the outcome of patients undergoing decompression alone for degenerative lumbar stenosis.

METHODS

We conducted a comprehensive search in the PubMed, Embase, and Cochrane Library databases. All comparative studies were included in this meta-analysis. The literature search, data extraction, and quality assessment were conducted by 2 independent reviewers. The functional outcomes were clinical scores and reoperation rate. The radiologic outcomes were slippage rate and postoperative instability rate.

RESULTS

A total of 11 studies with 1081 cases, including 469 cases of degenerative lumbar stenosis with DS (DS group) and 612 degenerative lumbar stenosis without spondylolisthesis (noDS group), were enrolled in our meta-analysis. There were no significant differences between the 2 groups for functional outcomes in terms of Japanese Orthopedic Association score, Japanese Orthopedic Association recovery rate, Oswestry Disability Index score, visual analog scale back/leg, and reoperation rate after decompression alone. For the radiologic outcomes, slippage rate was found not changed significantly before and after minimally invasive decompression alone in the DS group and the postoperative instability rate did not differ significantly between the 2 groups after decompression alone by a minimally invasive method.

CONCLUSIONS

Our meta-analysis revealed that concomitant DS (Meyerding grade I-II) does not influence the outcome of decompression alone in degenerative lumbar spinal stenosis, especially when a minimally invasive procedure was performed and patients did not have predominant symptoms of mechanical back pain. The presence of DS should not be an indication for fusion surgery in degenerative lumbar spinal stenosis.

Endoscopic posterior decompression under local anesthesia for degenerative lumbar spinal stenosis

OBJECTIVEVarious minimally invasive techniques have been described for the decompression of lumbar spinal stenosis (LSS). However, few reports have described the results of endoscopic posterior decompression (EPD) with laminectomy performed under local anesthesia. This study aimed to evaluate the clinical and radiological outcomes of EPD performed under local anesthesia in patients with LSS and to compare the procedural outcomes in patients with and without preoperative spondylolisthesis.METHODSFifty patients (28 female and 22 male) who underwent EPD under local anesthesia were included in this study. Patients were assessed before surgery and were followed up with regular outpatient visits (at 1, 3, 6, 12, and 24 months postoperatively). Clinical outcomes were evaluated using the visual analog scale (VAS), Oswestry Disability Index (ODI), and the 36-Item Short Form Survey (SF-36) outcome questionnaire. Radiological outcomes were assessed by measuring lumbar lordosis, disc-wedging angle, percentage of vertebral slippage, and disc height index on plain standing radiographs.RESULTSThe VAS, ODI, and SF-36 scores were significantly improved at 1 month after surgery compared to the baseline mean values, and the improved scores were maintained over the 2-year follow-up period. Radiological progression was found in 2 patients during the follow-up period. Patients with and without preoperative spondylolisthesis had no significant differences in their clinical and radiological outcomes.CONCLUSIONSEPD performed under local anesthesia is effective for LSS treatment. Similar favorable outcomes can be obtained in patients with and without preoperative spondylolisthesis using this approach.

Comparison of minimally invasive decompression and combined minimally invasive decompression and fusion in patients with degenerative spondylolisthesis with instability

Posterior lumbar interbody fusion with cortical bone trajectory (CBT-PLIF) is a form of minimally invasive decompression and fusion, whereas microendoscopic laminotomy (MEL) is a form of minimally invasive decompression surgery. No study has compared the clinical outcomes of the two methods for patients who have degenerative spondylolisthesis (DS) with instability. In this study, CBT-PLIF and MEL were both offered to 64 patients who met the inclusion criteria. Each patient then selected his or her preferred treatment. Twenty patients received CBT-PLIF. They were matched to 30 of the 44 patients receiving MEL based on age, sex, disease duration, and surgical levels. The 20 patients with CBT-PLIF formed the CBT group and the 30 matched patients with MEL formed the MEL group. At 2 years of follow-up, Japanese Orthopaedic Association scores improved to 72.6% and 70.5% in the CBT and MEL groups, respectively. The difference in scores was not statistically significant. Further, improvements in visual analogue scale scores for back and leg symptom did not differ significantly between the two groups. Regarding complications, 1 CBT-group patient (5%) had adjacent-segment degeneration and 7 MEL-group patients (23%) had same-segment degeneration. Three CBT-group patients (15%) and 5 MEL-group patients (16%) required reoperation within the follow-up period. In summary, among patients who had DS with instability, MEL and CBT-PLIF offered comparable clinical outcomes at 2 years of follow-up. Although the rate of segmental degeneration was relatively high in the MEL group, both groups had similar reoperation rates.

Effect of Sagittal Spinal Balance on the Outcome of Decompression Surgery for Lumbar Canal Stenosis

OBJECTIVE

Although sagittal spinal balance is known to affect the outcome of spinal deformity surgery, its effect on simple decompression surgery is not well understood.

MATERIALS AND METHODS

Patients who underwent unilateral laminotomy for bilateral decompression for lumbar canal stenosis were prospectively enrolled in the study. Before surgery and 6 months after surgery, the following sagittal-alignment parameters were measured: lumbar lordosis (LL), pelvic tilt (PT), pelvic incidence minus lumbar lordosis (PI-LL), and sagittal vertical axis (SVA). At the same time, short-form 36 (SF-36) and Visual Analogue Scale (VAS) were estimated. The patients were divided into the poor postoperative physical score group (P_poor), good postoperative physical score group (P_good), poor postoperative VAS group (V_poor), or good postoperative VAS group (V_good). The postoperative spinopelvic parameters were compared between the physical score and VAS groups, respectively. Finally, we examined the correlation between the spinopelvic parameters and the outcome scores using scatter plots and linear regression analysis.

RESULTS

Fifty-two patients were enrolled into the study. Although the spinopelvic parameters (LL, PT, PI-LL) significantly improved after surgery, the absolute values of improvement were relatively small. The postoperative spinopelvic parameters were significantly worse in the P_poor and the V_poor groups compared with the P_good and the V_good groups, respectively. The correlation analyses also showed that worse postoperative spinopelvic parameters correlated to worse outcome in SF-36 and VAS.

CONCLUSIONS

Sagittal spinal balance significantly affected the outcome of patients undergoing decompression surgery for lumbar canal stenosis, the knowledge of which may serve better patient management.

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.

Radiographic Risk Factors of Reoperation Following Minimally Invasive Decompression for Lumbar Canal Stenosis Associated With Degenerative Scoliosis and Spondylolisthesis

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

Microsurgical bilateral decompression via a unilateral approach (MBDU), a minimally invasive surgical (MIS) decompression method, has been performed for numerous degenerative lumbar diseases, including degenerative lumbar scoliosis (DLS) or degenerative spondylolisthesis (DS), at our institution. In this study, we evaluated the appropriateness of MBDU for DLS or DS patients.

METHODS

A total of 207 patients treated by MBDU were included (88 women and 119 men; mean age, 70 [40-86] years). Thirty-seven cases were diagnosed as DLS (group A), 51 as DS (group B), and 119 as lumbar canal stenosis (group C). Patient clinical status assessed by JOA score was evaluated preoperatively and 2 years postoperatively. We evaluated the prevalence of cases that required reoperation among the groups and the radiographic risk factors related to reoperation.

RESULTS

There was no significant difference in recovery ratios of JOA scores among the groups. Reoperation after MBDU was needed in 13 cases (6.3%); the revision rate did not significantly differ among the groups. Reoperation was associated with poor clinical status, low visual analog scale score for low back pain, and low SF-36 mental component summary score. Reoperation was significantly associated with preoperative scoliotic disc wedging with Cobb's angle ≥3° in L4-5 (odds ratio = 9.88) and lateral listhesis (odds ratio = 5.22 [total], 12.9 [L4-5]).

CONCLUSIONS

When we are careful to indicate decompression for patients with these risk factors related to reoperation, MIS decompression alone can successfully improve DLS patients with a Cobb's angle of ≤20° or DS patients.

Decompression plus fusion versus decompression alone for degenerative lumbar spondylolisthesis: a systematic review and meta-analysis

PURPOSE

To compare the clinical effectiveness of decompression plus fusion and decompression alone for patients with degenerative lumbar spondylolisthesis, a systematic review and meta-analysis of all available evidence was performed.

METHODS

A search of the literature was conducted on PubMed/MEDLINE, EMBASE, and the Cochrane Collaboration Library. Relevant studies comparing decompression plus fusion and decompression alone were selected according to eligibility criteria. Predefined endpoints were extracted and meta-analyzed from the identified studies.

RESULTS

Four randomized controlled trials and 13 observational studies were eligible. The pooled data revealed that fusion was associated with significantly higher rates of satisfaction and lower leg pain scores when compared with decompression alone. However, fusion significantly increased the intraoperative blood loss, operative time and hospital stay. Both techniques had similar ODI, back pain scores, complication rate, and reoperation rate.

CONCLUSIONS

Based on the available evidence, decompression plus fusion maybe be better than decompression alone in the treatment of degenerative spondylolisthesis. Fusion had advantages of improvement of clinical satisfaction, as well as reduction of postoperative leg pain, with similar complication rate to decompression alone.

Effectiveness of decompression alone versus decompression plus fusion for lumbar spinal stenosis: a systematic review and meta-analysis

INTRODUCTION

The debate on efficacy of fusion added to decompression for lumbar spinal stenosis (LSS) is ongoing. No meta-analysis has compared the effectiveness of decompression versus decompression plus fusion in treating patients with LSS.

METHODS

A literature search was performed in the Web of Science, PubMed, Embase, and Springer databases from 1970 to 2016. Relevant references were selected and the included studies were manually reviewed. We included trials evaluating decompression surgery compared to decompression plus fusion surgery in treating patients with LSS. The primary outcomes analyzed were back pain, leg pain, Oswestry Disability Index scores (ODI), the quality-of-life EuroQol-5 Dimensions (EQ-5D), duration of operation, intraoperative blood loss, length of hospital stay, major complications, walking ability, number of reoperation, and finally clinically excellent and good rates. Data analysis was conducted using the Review Manager 5.2 software.

RESULTS

Fifteen studies involving 17,785 patients with LSS were included. The overall effect mean difference (MD) (95% CI) in the differences between pre- and post-operative back pain, leg pain, operative time, intraoperative blood loss, and length of stay were 0.04 (-0.36, 0.44), 0.69 (-0.38, 1.76), -2.04 (-3.12, -0.96), -3.96 (-6.64, -1.27) and -4.21 (-10.03, 1.62) (z = 0.18, 1.26, 3.71, 2.89 and 1.41, respectively; P = 0.86, 0.55, 0.0002, 0.004 and 0.16, respectively) in random effects models. The overall effect MD (95% CI) in ODI, EQ-5D, and walking ability were 0.43 (-1.15, 2.00), 0.01 (-0.01, 0.03) and 0.04 (-0.49, 0.57) (z = 0.52, 1.16 and 0.15, respectively; P = 0.59, 0.24 and 0.88, respectively) in fixed effects models. The overall effect odds ratio (OR) (95% CI) of major complications, number of reoperations, and clinically excellent and good rates between the two groups were 0.70 (0.60, 0.81), 1.04 (0.90, 1.19) and 0.31 (0.06, 1.59) (z = 4.63, 0.53 and 1.40, respectively; P < 0.00001, 0.60 and 0.16, respectively). Our study reveals no difference in the effectiveness between the two surgical techniques.

CONCLUSIONS

The additional fusion in the management of LSS yielded no clinical improvements over decompression alone within a 2-year follow-up period. But fusion resulted in a longer duration of operation, more blood loss, and a higher risk of complications. Therefore, the appropriate surgical protocol for LSS should be discussed further.

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.

Clinical Outcome of Cervical Laminoplasty and Postoperative Radiological Change for Cervical Myelopathy With Degenerative Spondylolisthesis

STUDY DESIGN

A retrospective cohort study with prospectively collected data.

OBJECTIVE

The aim of this study was to investigate the clinical and radiological outcome of cervical laminoplasty for cervical myelopathy with degenerative spondylolisthesis.

SUMMARY OF BACKGROUND DATA

The presence of spondylolisthesis is thought to represent segmental instability in spine. Cervical laminoplasty is a common decompression surgery for cervical myelopathy, but its clinical result for cervical spondylolisthesis has not been well studied.

METHODS

One hundred seventeen patients who underwent cervical laminoplasty for degenerative cervical myelopathy were included. Japanese Orthopaedic Association score (JOA score) and visual analog scale of neck pain, upper arm pain and numbness were evaluated before surgery, and at scheduled time points after surgery. Spondylolisthesis was defined as more than 2 mm slip on plain radiograph, and the clinical results were compared between the patients with spondylolisthesis (group S) and without spondylolisthesis (group C). In the patients with spondylolisthesis, the slip distance and translational motion between flexion and extension was examined on plain lateral radiograph before surgery and 2 years after surgery.

RESULTS

Degenerative cervical spondylolisthesis was found in 49 levels of 33 patients (28.2%), and the average age of group S was significantly higher than group C. JOA score and each VAS score was significantly improved after surgery in both groups. Average JOA score of group S was significantly lower than group C at every time points, but the recovery rate was similar between the two groups. In the level of spondylolisthesis, average slip distance did not changed, but average translational motion was significantly decreased in 2years after surgery.

CONCLUSION

Cervical spondylolisthesis was common in elderly patients. The clinical outcome in group S was comparable with group C, and the level with spondylolisthesis has been stabilized after surgery. Thus, laminoplasty can be a treatment option even for cervical myelopathy with degenerative spondylolisthesis.

LEVEL OF EVIDENCE

3.

Commentary on: Laminectomy plus fusion versus laminectomy alone for lumbar spondylolisthesis by Ghogawala Z, Dziura J, Butler WE, Dai F, Terrin N, Magge SN, et al. NEJM 2016;374 (15):1424-34

Background:

How does an article involving only 66 patients randomized into two spinal surgical groups get into the New England Journal of Medicine? Nevertheless, this one did. The article by Ghogawala et al. entitled Laminectomy plus fusion versus laminectomy alone for lumbar spondylolisthesis, compared the efficacy/outcomes of pedicle/screw/rod instrumented posterolateral lumbar fusions vs. decompressions alone for treating lumbar stenosis with grade I degenerative spondylolisthesis (DS).

Methods:

They designed a randomized controlled study involving only 66 patients between the ages of 50–80 (average age: 67) with lumbar stenosis and stable DS (3–14 mm). Outcomes were measured utilizing the physical measures from the Short Form 36 (SF-36) up to 4 postoperative years, and the Oswestry Disability Index (ODI) upt to 2 postoperative years. Data were available for 86% of patients at 2, but only for 68% of the patients at 4 postoperative years.

Results:

At 2 postoperative years, SF-36 scores were higher for the instrumented patients (28 patients) vs. decompressed (29 patients) patients. However, the scores were comparable for both groups using the ODI at 4 years. SF-36 scores, however, remained higher for the 19 remaining instrumented patients. Additionally, reoperation rates were 14% for fusions and a staggering 34% for decompressions alone.

Conclusions:

The authors concluded; laminectomy with fusion offered a “slightly greater but clinically meaningful improvement in overall physical health-related quality of life vs. laminectomy alone.” Rather, it should have read there were no statistically significant differences between the two groups and an insufficient number of patients were included in the study at all stages.

The effectiveness of decompression alone compared with additional fusion for lumbar spinal stenosis with degenerative spondylolisthesis: a pragmatic comparative non-inferiority observational study from the Norwegian Registry for Spine Surgery

PURPOSE

To evaluate the effect of adding fusion to decompression in patients operated for lumbar spinal stenosis with a concomitant lumbar degenerative spondylolisthesis.

METHODS

After propensity score matching, 260 patients operated with decompression and fusion and 260 patients operated with decompression alone were compared. Primary outcome measures were leg and back pain [Numeric Rating Scale (NRS), 0-10] and Oswestry Disability Index (ODI, 0-100) at 12 months.

RESULTS

At 12-month follow-up, the fusion group rated their pain significantly lower than the decompression alone group [leg pain 3.0 and 3.6, respectively, mean difference -0.6, 95 % confidence interval (CI) -1.2 to -0.05, p = 0.03 and back pain 3.3 and 3.9, respectively, mean difference -0.6, 95 % CI -1.1 to -0.1, p = 0.02]. ODI was not significantly different between the groups (21.0 versus 23.3, mean difference -2.3, 95 % CI -5.8 to 1.1, p = 0.18). Seventy-four percent of the fusion group and 63 % of the decompression alone group achieved a clinically important improvement in back pain (difference in proportion of responders = 11 %, 95 % CI 2-20 %, p = 0.01), corresponding to a number needed to treat of 9 patients (95 % CI 5-50). There was no significant difference in responder rate for leg pain (74 and 67 %, respectively, difference 7 %, 95 % CI -1 to 16 %, p = 0.09) or for ODI (67 and 59 %, respectively, difference 8 %, 95 % CI 0-18 %, p = 0.06). The duration of surgery and hospital stay was longer for the fusion group (mean difference 68 min, 95 % CI 58-78, p < 0.01 and mean difference 4.2 days, 95 % CI 3.5-4.8, p < 0.01).

CONCLUSION

In the present non-inferiority study, we cannot conclude that decompression alone is as good as decompression with additional fusion. However, the small differences in the groups' effect sizes suggest that a considerable number of patients can be treated with decompression alone. A challenge in future studies will be to find the best treatment option for each patient.

Iatrogenic spondylolisthesis following laminectomy for degenerative lumbar stenosis: systematic review and current concepts

OBJECT Decompression without fusion for degenerative lumbar stenosis is an effective treatment for both the pain and disability of neurogenic claudication. Iatrogenic instability following decompression may require further intervention to stabilize the spine. The authors review the incidence of postsurgical instability following lumbar decompression, and assess the impact of surgical technique as well as study design on the incidence of instability. METHODS A comprehensive literature search was performed to identify surgical cohorts of patients with degenerative lumbar stenosis, with and without preexisting spondylolisthesis, who were treated with laminectomy or minimally invasive decompression without fusion. Data on patient characteristics, surgical indications and techniques, clinical and radiographic outcomes, and reoperation rates were collected and analyzed. RESULTS A systematic review of 24 studies involving 2496 patients was performed, assessing both open laminectomy and minimally invasive bilateral canal enlargement. Postoperative pain and functional outcomes were similar across the various studies, and postoperative radiographie instability was seen in 5.5% of patients. Instability was seen more frequently in patients with preexisting spondylolisthesis (12.6%) and in those treated with open laminectomy (12%). Reoperation for instability was required in 1.8% of all patients, and was higher for patients with preoperative spondylolisthesis (9.3%) and for those treated with open laminectomy (4.1%). CONCLUSIONS Instability following lumbar decompression is a common occurrence. This is particularly true if decompression alone is selected as a surgical approach in patients with established spondylolisthesis. This complication may occur less commonly with the use of minimally invasive techniques; however, larger prospective cohort studies are necessary to more thoroughly explore these findings.

Laminectomy plus Fusion versus Laminectomy Alone for Lumbar Spondylolisthesis

BACKGROUND

The comparative effectiveness of performing instrumented (rigid pedicle screws affixed to titanium alloy rods) lumbar spinal fusion in addition to decompressive laminectomy in patients with symptomatic lumbar grade I degenerative spondylolisthesis with spinal stenosis is unknown.

METHODS

In this randomized, controlled trial, we assigned patients, 50 to 80 years of age, who had stable degenerative spondylolisthesis (degree of spondylolisthesis, 3 to 14 mm) and symptomatic lumbar spinal stenosis to undergo either decompressive laminectomy alone (decompression-alone group) or laminectomy with posterolateral instrumented fusion (fusion group). The primary outcome measure was the change in the physical-component summary score of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36; range, 0 to 100, with higher scores indicating better quality of life) 2 years after surgery. The secondary outcome measure was the score on the Oswestry Disability Index (range, 0 to 100, with higher scores indicating more disability related to back pain). Patients were followed for 4 years.

RESULTS

A total of 66 patients (mean age, 67 years; 80% women) underwent randomization. The rate of follow-up was 89% at 1 year, 86% at 2 years, and 68% at 4 years. The fusion group had a greater increase in SF-36 physical-component summary scores at 2 years after surgery than did the decompression-alone group (15.2 vs. 9.5, for a difference of 5.7; 95% confidence interval, 0.1 to 11.3; P=0.046). The increases in the SF-36 physical-component summary scores in the fusion group remained greater than those in the decompression-alone group at 3 years and at 4 years (P=0.02 for both years). With respect to reductions in disability related to back pain, the changes in the Oswestry Disability Index scores at 2 years after surgery did not differ significantly between the study groups (-17.9 in the decompression-alone group and -26.3 in the fusion group, P=0.06). More blood loss and longer hospital stays occurred in the fusion group than in the decompression-alone group (P<0.001 for both comparisons). The cumulative rate of reoperation was 14% in the fusion group and 34% in the decompression-alone group (P=0.05).

CONCLUSIONS

Among patients with degenerative grade I spondylolisthesis, the addition of lumbar spinal fusion to laminectomy was associated with slightly greater but clinically meaningful improvement in overall physical health-related quality of life than laminectomy alone. (Funded by the Jean and David Wallace Foundation and others; SLIP ClinicalTrials.gov number, NCT00109213.).

Dynamic stabilization for degenerative spondylolisthesis and lumbar spinal instability

Lumbar interbody fusion is a widely accepted surgical procedure for patients with lumbar degenerative spondylolisthesis and lumbar spinal instability in the active age group. However, in elderly patients, it is often questionable whether it is truly necessary to construct rigid fixation for a short period of time. In recent years, we have been occasionally performing posterior dynamic stabilization in elderly patients with such lumbar disorders. Posterior dynamic stabilization was performed in 12 patients (6 women, 70.9 ± 5.6 years old at the time of operation) with lumbar degenerative spondylolisthesis in whom % slip was less than 20% or instability associated with lumbar disc herniation between March 2011 and March 2013. Movement occurs through the connector linked to the pedicle screw. In practice, 9 pairs of D connector system where the rod moves in the perpendicular direction alone and 8 pairs of Dynamic connector system where the connector linked to the pedicle screw rotates in the sagittal direction were installed. The observation period was 77–479 days, and the mean recovery rate of lumbar Japanese Orthopedic Association (JOA) score was 65.6 ± 20.8%. There was progression of slippage due to slight loosening in a case with lumbar degenerative spondylolisthesis, but this did not lead to exacerbation of the symptoms. Although follow-up was short, there were no symptomatic adjacent vertebral and disc disorders during this period. Posterior dynamic stabilization may diminish the development of adjacent vertebral or disc disorders due to lumbar interbody fusion, especially in elderly patients, and it may be a useful procedure that facilitates decompression and ensures a certain degree of spinal stabilization.