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

The Lumbosacral Fractional Curve in Adult Degenerative Scoliosis

Spine surgeons are often faced with a profoundly difficult challenge in surgically treating adult degenerative scoliosis. Deformity correction surgery is complicated by the difficulty in offering extensive surgical corrections to the elderly, complication-prone population it commonly affects. As spine surgeons attempt to offer minimally invasive solutions to this disease process, the need for fusion of the fractional curve at L4, L5, and S1 may be discounted. A treatment strategy to identify, address, and treat the fractional curve with either open or minimally invasive techniques can lead to improved patient outcomes and decrease revision rates in this complicated pathologic process.

A systematic review and meta-analysis of risk factors for reoperation after degenerative lumbar spondylolisthesis surgery

BACKGROUND

Considering the high reoperation rate in degenerative lumbar spondylolisthesis (DLS) patients undergoing lumbar surgeries and controversial results on the risk factors for the reoperation, we performed a systematic review and meta-analysis to explore the reoperation rate and risk factors for the reoperation in DLS patients undergoing lumbar surgeries.

METHODS

Literature search was conducted from inception to October 28, 2022 in Pubmed, Embase, Cochrane Library, and Web of Science. Odds ratio (OR) was used as the effect index for the categorical data, and effect size was expressed as 95% confidence interval (CI). Heterogeneity test was performed for each outcome effect size, and subgroup analysis was performed based on study design, patients, surgery types, follow-up time, and quality of studies to explore the source of heterogeneity. Results of all outcomes were examined by sensitivity analysis. Publication bias was assessed using Begg test, and adjusted using trim-and-fill analysis.

RESULTS

A total of 39 cohort studies (27 retrospective cohort studies and 12 prospective cohort studies) were finally included in this systematic review and meta-analysis. The overall results showed a 10% (95%CI: 8%-12%) of reoperation rate in DLS patients undergoing lumbar surgeries. In surgery types subgroup, the reoperation rate was 11% (95%CI: 9%-13%) for decompression, 10% (95%CI: 7%-12%) for fusion, and 9% (95%CI: 5%-13%) for decompression and fusion. An increased risk of reoperation was found in patients with obesity (OR = 1.91, 95%CI: 1.04-3.51), diabetes (OR = 2.01, 95%CI: 1.43-2.82), and smoking (OR = 1.51, 95%CI: 1.23-1.84).

CONCLUSIONS

We found a 10% of reoperation rate in DLS patients after lumbar surgeries. Obesity, diabetes, and smoking were risk factors for the reoperation.

A decision tree analysis to predict clinical outcome of minimally invasive lumbar decompression surgery for lumbar spinal stenosis with and without coexisting spondylolisthesis and scoliosis

BACKGROUND CONTEXT

Implementing machine learning techniques, such as decision trees, known as prediction models that use logical construction diagrams, are rarely used to predict clinical outcomes.

PURPOSE

To develop a clinical prediction rule to predict clinical outcomes in patients who undergo minimally invasive lumbar decompression surgery for lumbar spinal stenosis with and without coexisting spondylolisthesis and scoliosis using a decision tree model.

STUDY DESIGN/SETTING

A retrospective analysis of prospectively collected data.

PATIENT SAMPLE

This study included 331 patients who underwent minimally invasive surgery for lumbar spinal stenosis and were followed up for ≥2 years at 1 institution.

OUTCOME MEASURES

Self-report measures: The Japanese Orthopedic Association (JOA) scores and low back pain (LBP)/leg pain/leg numbness visual analog scale (VAS) scores. Physiologic measures: Standing sagittal spinopelvic alignment, computed tomography, and magnetic resonance imaging results.

METHODS

Low achievement in clinical outcomes were defined as the postoperative JOA score at the 2-year follow-up <25 points. Univariate and multiple logistic regression analysis and chi-square automatic interaction detection (CHAID) were used for analysis.

RESULTS

The CHAID model for JOA score <25 points showed spontaneous numbness/pain as the first decision node. For the presence of spontaneous numbness/pain, sagittal vertical axis ≥70 mm was selected as the second decision node. Then lateral wedging, ≥6° and pelvic incidence minus lumbar lordosis (PI-LL) ≥30° followed as the third decision node. For the absence of spontaneous numbness/pain, sex and lateral olisthesis, ≥3mm and American Society of Anesthesiologists physical status classification system score were selected as the second and third decision nodes. The sensitivity, specificity, and the positive predictive value of this CHAID model was 65.1, 69.8, and 64.7% respectively.

CONCLUSIONS

The CHAID model incorporating basic information and functional and radiologic factors is useful for predicting surgical outcomes.

Decompression Alone in the Setting of Adult Degenerative Lumbar Scoliosis and Stenosis: A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.OBJECTIVESSurgical decompression alone for patients with neurogenic leg pain in the setting of degenerative lumbar scoliosis (DLS) and stenosis is commonly performed, however, there is no summary of evidence for outcomes.

METHODS

A systematic search of English language medical literature databases was performed for studies describing outcomes of decompression alone in DLS, defined as Cobb angle >10˚, and 2-year minimum follow-up. Three outcomes were examined: 1) Cobb angle progression, 2) reoperation rate, and 3) ODI and overall satisfaction. Data were pooled and weighted averages were calculated to summarize available evidence.

RESULTS

Across 15 studies included in the final analysis, 586 patients were examined. Average preoperative and postoperative Cobb angles were 17.6˚ (Range: 12.7 - 25˚) and 18.0 (range 14.1 - 25˚), respectively. Average change in Cobb angle was an increase of 1.8˚. Overall rate of reoperation ranged from 3 to 33% with an average of 9.7%. Average ODI before surgery, after surgery, and change in scores were 56.4%, 27.2%, and an improvement of 29% respectively. Average from 8 studies that reported patient satisfaction was 71.2%.

CONCLUSIONS

Current literature on decompression alone in the setting of DLS is sparse and is not high quality, limited to patients with small magnitude of lumbar coronal Cobb angle, and heterogenous in the type of procedure performed. Based on available evidence, select patients with DLS who undergo decompression alone had minimal progression of Cobb angle, relatively low reoperation rate, and favorable patient-reported outcomes.

Correlation between direction of pedicle screw and restoration of lumbar degenerative scoliosis in degenerative lumbar spondylolisthesis: a retrospective study

Background

Inferior clinical outcomes have been reported in patients with degenerative lumbar spondylolisthesis (DLS) accompanied by lumbar degenerative scoliosis, but little attention has been paid to its radiologic assessment or preoperative planning. The aim of this study was to analyze the effect of transforaminal lumbar interbody fusion on patients with DLS and lumbar degenerative scoliosis and explore the surgical aspects benefiting the restoration of lumbar degenerative scoliosis.

Methods

All patients with DLS and lumbar degenerative scoliosis undergoing single-level unilateral transforaminal lumbar interbody fusion surgery between July 1, 2015, and April 30, 2021, were screened in this retrospective cohort study. Clinical outcomes including visual analog scale (VAS), Oswestry disability index (ODI), and radiographic parameters of sagittal and coronal alignment, cage spatial locations, and angle of pedicle screw (parallel, cranial, and caudad angle) were assessed. Coronal asymmetry was demonstrated by the intervertebral height difference between the medial and lateral margins of indexed intersegmental space. The correlations between Δintervertebral height difference (postoperative intervertebral height difference-preoperative intervertebral height difference) and radiographic parameters and clinical outcomes were analyzed by univariable, multivariable, mediation, and correlation analyses. Significance was set at a bilateral P<0.05.

Results

A total of 57 included patients were followed up for a minimum of 1 year. Reduction of VAS, ODI, and improvement of radiographic parameters were found after surgery. The cranial angle of the lower pedicle screw positively correlated with Δintervertebral height difference restoration (b=0.54; standard error=0.11; P<0.001).

Conclusions

Transforaminal lumbar interbody fusion surgery appears to be an effective approach to improving the radiographic and clinical outcomes of patients with DLS and lumbar degenerative scoliosis. The cranial direction of the lower pedicle screws in single-level unilateral transforaminal lumbar interbody fusion surgery may be associated with a better postoperative restoration of lumbar degenerative scoliosis.

Magnetic Resonance Imaging Proxies for Segmental Instability in Degenerative Lumbar Spondylolisthesis Patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim was to investigate whether findings on magnetic resonance imaging (MRI) can be proxies (MRIPs) for segmental instability in patients with degenerative lumbar spinal stenosis (LSS) and/or degenerative spondylolisthesis (LDS) L4/L5.

BACKGROUND

LDS has a heterogeneous nature. Some patients have a dynamic component of segmental instability associated with LDS. Studies have shown that MRI can show signs of instability.

METHODS

Patients with LSS or LDS at L4/L5 undergoing decompressive surgery±fusion from 2010 to 2017, with preoperative standing lateral spine radiographs and supine lumbar MRI and enrolled in Danish national spine surgical database, DaneSpine. Instability defined as slip of >3 mm on radiographs. Patients divided into two groups based upon presence of instability. Outcome measures: radiograph: sagittal slip (mm). MRIPs for instability: sagittal slip >3 mm, facet joint angle (°), facet joint effusion (mm), disk height index (%), and presence of vacuum phenomena. Optimal thresholds for MRIPs was determined by receiver operating characteristic (ROC) curves and area under the curve (AUC). Logistic regression to investigate association between instability and MRIPs.

RESULTS

Two hundred thirty-two patients: 47 stable group and 185 unstable group. The two groups were comparable with regard to baseline patient-reported outcome measures. Thresholds for MRIPs: bilateral facet joint angle ≥46°; bilateral facet effusion ≥1.5 mm and disk height index ≥13%. Logistic regression showed statistically significant association with MRIPs except vacuum phenomena, ROC curve AUC of 0.951. By absence of slip on MRI logistic regression showed statistically significant association between instability on radiograph and the remaining MRIPs, ROC curve AUC 0.757.

CONCLUSION

Presence of MRIPs for instability showed statistically significant association with instability and excellent ability to predict instability on standing radiograph in LSS and LDS patients. Even in the absence of slip on MRI the MRIPs had a good ability to discriminate presence of instability.

Comparison between Decompression Alone and with Additional Fusion for Degenerative Lumbar Spondylolisthesis: A Systematic Review and Meta-Analysis

Introduction

Degenerative lumbar spondylolisthesis affects approximately 10% of adults over 40. Although decompression has been the treatment of choice, some surgeons note possible instability development after decompression alone (D). Previous studies show that decompression with fusion (DF) has similar complication rates but is better at preventing slip progression and reducing pain. However, others stated the additional instrumentation does not result in superior functional outcomes and has higher costs and complication rates. This study aims to provide an objective, two-arm comparison of the two treatments using systematic review and meta-analysis.

Methods

The study design was a systematic review and meta-analysis of relevant randomized controlled trials and nonrandomized comparative studies. A systematic search was conducted from April 2021 to September 2021 to identify relevant studies using PubMed, Google Scholar, EMBASE, and Cochrane databases based on PRISMA guidelines.

Results

This systematic review included 8 studies (6,669 patients); 7 (6,569 patients) were included in the meta-analysis, with a follow-up period of up to 143 months. The most commonly affected level was L4-5, with females being more affected than males. Visual Analog Scale improvement on back pain was significantly better in DF group (Heterogeneity, I²=32%; WMD -0.72; 95% Confidence Interval (CI), -1.35 to -0.08; P=0.03), as well as postoperative back pain (I²=96%; WMD 0.87; 95% CI, 0.19 to 1.55; P=0.01). The leg pain, Oswestry Disability Index (ODI), satisfaction rate, complication rate, and revision rate were comparable between the two procedures.

Conclusions

Current systematic review and meta-analysis proved that DF is better than D in terms of back pain improvement, and the two procedures are comparable in terms of leg pain, ODI, satisfaction rate, complication rate, and revision rate.

Mid-term changes in spinopelvic sagittal alignment in lumbar spinal stenosis with coexisting degenerative spondylolisthesis or scoliosis after minimally invasive lumbar decompression surgery: minimum five-year follow-up

BACKGROUND CONTEXT

Recently, the number of patients with lumbar spinal stenosis (LSS) who present with a coexisting spinal deformity such as degenerative spondylolisthesis (DS) and scoliosis (DLS) has been increasing. Lumbar decompression without fusion can lead to a reactive improvement in the lumbar and sagittal spinopelvic alignment, even if a sagittal imbalance exists preoperatively. However, the mid- to long-term impact of the coexistence of DS and DLS on the change in sagittal spinopelvic alignment and clinical outcomes after decompression surgery remains unknown.

PURPOSE

This study aimed to investigate whether the coexistence of DS or DLS in patients with LSS is associated with differences in radiological and clinical outcomes after minimally invasive lumbar decompression surgery.

STUDY DESIGN/SETTING

A retrospective analysis of prospectively collected data.

PATIENT SAMPLE

A total of 169 patients who underwent minimally invasive lumbar decompression surgery and follow-up >5 years postoperatively.

OUTCOME MEASURES

Self-report measures: Low back pain (LBP) and/or leg pain and/or leg numbness visual analog scale (VAS) scores and the Japanese Orthopedic Association scores.

PHYSIOLOGIC MEASURES

Standing sagittal spinopelvic alignment.

METHODS

In total, 81 patients with LSS, 50 patients with LSS and DS (≥3 mm anterior slippage), and 38 patients with LSS and DLS (≥15° coronal Cobb angle) were included in the current study. Clinical and radiological outcome results before surgery and at 2 and 5 years after surgery were compared among the groups.

RESULTS

In patients with LSS with coexisting DS, the clinical outcomes at 2, and 5 years after surgery were similar to those of patients with only LSS. In patients with LSS with coexisting DLS, the VAS LBP and leg pain at 2 years after surgery was significantly higher (34.7 vs. 27.8, p=0.014; 27.8 vs. 14.7, p=0.028) and the achievement rate of the minimal clinically important difference in VAS LBP and leg pain was significantly lower than that of the LSS group (36.1% vs. 54.2%, p=0.036; 58.3% vs. 69.9%, p=0.10). The clinical outcomes except VAS leg numbness at 5 years after surgery were similar to those of patients with only LSS. The reoperation rate of the DS group was significantly lower than that of the LSS group (4.0% vs. 14.8%; p=0.01); however, the reoperation rate of the DLS group was comparable to that of the LSS group (15.8% vs. 14.8%; p=0.493). Lumbar lordosis (LL), sacral slope, pelvic tilt, and pelvic incidence-LL had significantly improved and been maintained for 5 years after the surgery in both the DS and the DLS groups. The sagittal vertical axis had improved at two-year follow-up; however, no significant difference was observed at the 5-year follow-up in both the DS, and the DLS groups.

CONCLUSIONS

Mid-term clinical outcomes in patients with LSS with and without deformity were comparable. Lumbar decompression without fusion can result in a reactive improvement in the lumbar and sagittal spinopelvic alignment, even with coexisting DS or DLS. Minimally invasive surgery could be considered for most patients with LSS.

Evaluation of the Predictors for Unfavorable Clinical Outcomes of Degenerative Lumbar Spondylolisthesis After Lumbar Interbody Fusion Using Machine Learning

Background

An increasing number of geriatric patients are suffering from degenerative lumbar spondylolisthesis (DLS) and need a lumbar interbody fusion (LIF) operation to alleviate the symptoms. Our study was performed aiming to determine the predictors that contributed to unfavorable clinical efficacy among patients with DLS after LIF according to the support vector machine (SVM) algorithm.

Methods

A total of 157 patients with single-segment DLS were recruited and performed LIF in our hospital from January 1, 2015 to October 1, 2020. Postoperative functional evaluation, including ODI and VAS were, performed, and endpoint events were defined as significant relief of symptom in the short term (2 weeks postoperatively) and long term (1 year postoperatively). General patient information and radiological data were selected and analyzed for statistical relationships with the endpoint events. The SVM method was used to establish the predictive model.

Results

Among the 157 consecutive patients, a postoperative unfavorable clinical outcome was reported in 26 patients (16.6%) for a short-term cohort and nine patients (5.7%) for a long-term cohort. Based on univariate and multivariate regression analysis, increased disc height (DH), enlarged facet angle (FA), and raised lateral listhesis (LLS) grade were confirmed as the risk factors that hindered patients' short-term functional recovery. Furthermore, long-term functional recovery was significantly associated with DH alone. In combination with the SVM method, a prediction model with consistent and superior predictive performance was achieved with average and maximum areas under the receiver operating characteristic curve (AUC) of 0.88 and 0.96 in the short-term cohort, and 0.78 and 0.82 in the long-term cohort. The classification results of the discriminant analysis were demonstrated by the confusion matrix.

Conclusions

The proposed SVM model indicated that DH, FA, and LLS were statistically associated with a clinical outcome of DLS. These results may provide optimized clinical strategy for treatment of DLS.

Long-term reoperation rates and causes for reoperations following lumbar microendoscopic discectomy and decompression: 10-year follow-up

OBJECTIVE

To investigate the 10-year rates and causes of reoperations following lumbar microendoscopic discectomy for disc herniation (MEDH) and microendoscopic decompression for spinal stenosis (MEDS), as well as to define the reoperations at index and different lumbar levels.

METHODS

Between June 2005 and May 2011, the same surgeon had been using MEDH and/or MEDS on 355 consecutive patients. The follow-up rate was 88.3%. The causes and rates of reoperations (RORs) were determined at 10 years after the initial operations.

RESULTS

The 10-year reoperation rate for all patients combined was 22.1% (67/303). The 10-year reoperation rate for all cases that underwent repeat operations in the same segment was 16.5% (50/303); the most frequent reason for reoperation (FRR) was recurrence of disc herniation (ROR, 25/251 = 9.96%), the second FRR was an increase of postoperative spondylolisthesis and/or instability (ROR, 8/303 = 2.64%), and the third FRR was surgical site infection (ROR, 5/303 = 1.65%). Ten-year reoperation rate for all cases that underwent repeat operation at different lumbar levels was 5.61% (17/303); the most FRR was new disc herniation at another lumbar level (ROR, 10/303 = 3.30%), the second FRR was residual segmental stenosis (ROR, 4/303 = 1.32%), and the third FRR was new segmental stenosis at other lumbar levels (ROR, 2/303 = 0.66%).

CONCLUSIONS

Three-fourths of all repeat operations were conducted in the same segment and one-fourth were performed at different lumbar levels. We believe that it is important to understand and prevent related problems.

Less Invasive Decompressive Laminectomy and One-Level Lumbar Fusion in the Setting of Interspinous Fixation: A Retrospective Analysis of 15 Patients

Lumbar decompressive laminectomy for spinal stenosis can be performed using a less-invasive, unilateral approach with subperiosteal dissection and decompression by undermining the lamina from the ipsilateral to the contralateral side. A unilateral approach to bilateral decompression can be supplemented with interspinous instrumentation and facet fusion, a combined procedure that has not been studied before. The less-invasive technique appears to be as effective for lumbar stenosis as the traditional lumbar laminectomy. It also causes less blood loss and reduced operating time, and so may benefit patients who are elderly, medically frail, or with multiple comorbidities. 

Fifteen patients (eight females, seven males) underwent outpatient surgery by the author (HA) using this technique. These patients complained of progressive lower back pain associated with radicular pain exacerbated by prolonged standing or walking with improvement in flexed position of the lumbar spine with decreased walking distance ability. A one-level less-invasive lumbar laminectomy and foraminotomy with facet fusion and interspinous fixation were performed for spinal stenosis in conjunction with a Grade I degenerative spondylolisthesis. These patients all had a single-level facet fusion with bone graft material and local autograft. The approximate surgical time for each patient was between 50 and 80 minutes. The visual analog scale for pain (VAS) score decreased significantly after surgery; patients presented with preoperative VAS scores of 5-10/10 (mean 8.33/10). Postoperative VAS scores were 0-6/10 (mean 2/10), yielding a mean VAS improvement of 76% following surgery. Future analysis should be performed for evaluation of sustained VAS score, Oswestry Disability Index (ODI), Form 36 Health Survey Questionnaire (SF 36), and the Zurich Claudication Questionnaire (ZCQ).

Incidence, Risk, and Outcome of Pedicle Screw Loosening in Degenerative Lumbar Scoliosis Patients Undergoing Long-Segment Fusion

STUDY DESIGN

Retrospective study.

OBJECTIVE

To investigate the incidence, risk factors, and outcomes of pedicle screw loosening in degenerative lumbar scoliosis (DLS) undergoing long-segment spinal fusion surgery.

METHODS

One hundred and thirty DLS patients who underwent long-segment fusion surgery with at least a 12-month follow-up were studied. The incidence and risk factors of screw loosening were investigated. VAS, SRS-22, and ODI scores were obtained preoperatively and at follow-up.

RESULTS

One hundred and sixty-eight of 1784 (9.4%) screws showed evidence of loosening in 71 (54.6%) patients. Three patients required revision surgery. Screw loosening rates according to vertebral insertion level were lowest instrumented vertebra (LIV): 45.4%; uppermost instrumented vertebra (UIV):17.7%; one vertebra above the LIV: 0.5%; 2 vertebrae above the LIV: 0.4%. Multiple logistic regression analysis of possible risk factors indicated that preoperative lateral subluxation ≥8 mm (odds ratio [OR]: 2.68, 95% confidence interval [CI]: 1.16-6.20), osteopenia (OR: 5.52, 95% CI: 1.64-18.56), osteoporosis (OR: 8.19, 95% CI: 2.40-27.97), fusion to sacrum (OR: 2.55, 95% CI: 1.12-5.83), postoperative TLK greater than 10° (OR: 2.63, 95% CI: 1.14-6.04) and SVA imbalance (OR: 3.44, 95% CI: 1.17-10.14) were statistically significant. No difference was noted in preoperative, follow-up, and change of VAS, ODI, and SRS-22 scores.

CONCLUSIONS

Screw loosening in DLS underwent long-segment surgery is common and tends to occur in the LIV or UIV. Lateral subluxation ≥8 mm, osteopenia, osteoporosis, fusion to the sacrum, postoperative TLK greater than 10°, and SVA imbalance were the independent influencing factors. Screw loosening can be asymptomatic, while longer-term follow-up is required.

Classification and prognostic factors of residual symptoms after minimally invasive lumbar decompression surgery using a cluster analysis: a 5-year follow-up cohort study

PURPOSE

Residual symptoms indicating incomplete remission of lower leg numbness or low back pain may occur after spine surgery. The purpose was to elucidate the pattern of residual symptoms 5 years after minimally invasive lumbar decompression surgery using a cluster analysis.

METHODS

The study comprised 193 patients with lumbar spinal stenosis (LSS) (108 men, 85 women) ranging in age from 40 to 86 years (mean, 67.9 years). Each patient underwent 5-year follow-up. The Japanese Orthopedic Association score and visual analog scale scores for low back pain, leg pain, and leg numbness at 5 years were entered into the cluster analysis to characterize postoperative residual symptoms. Other clinical data were analyzed to detect the factors significantly related to each cluster.

RESULTS

The analysis yielded four clusters representing different patterns of residual symptoms. Patients in cluster 1 (57.0%) were substantially improved and had few residual symptoms of LSS. Patients in cluster 2 (11.4%) were poorly improved and had major residual symptoms. Patients in cluster 3 (17.6%) were greatly improved but had mild residual low back pain. Patients in cluster 4 (14.0%) were improved but had severe residual leg numbness. Prognostic factors of cluster 2 were a short maximum walking distance, motor weakness, resting lower leg numbness, cofounding scoliosis, and high sagittal vertical axis.

CONCLUSIONS

This is the first study to identify specific patterns of residual symptoms of LSS after decompression surgery. Our results will contribute to acquisition of preoperative informed consent and identification of patients with the best chance of postoperative improvement.

Lumbar alignment and patient-reported outcomes after single-level transforaminal lumbar interbody fusion for degenerative lumbar spondylolisthesis with and without local coronal imbalance

OBJECTIVE

The purpose of this study was to compare the preoperative radiographic features of degenerative lumbar spondylolisthesis (DLS) with and without local coronal imbalance (LCI) and to investigate the surgical outcomes of transforaminal lumbar interbody fusion (TLIF) in the treatment of DLS with LCI at the spondylolisthesis level. DLS with scoliotic disc wedging and/or lateral listhesis at the same involved segment, as well as LCI, constitutes a distinct subgroup. However, previous studies concerning surgical outcomes focused mainly on sagittal profiles. There is a paucity of valid data regarding lumbar coronal alignment and patient-reported outcomes (PROs) after surgery in DLS with LCI.

METHODS

The authors reviewed consecutive patients who received TLIF for L4/5 DLS between 2009 and 2018. Patients were assigned to the LCI and non-LCI groups based on preoperative radiographs. Demographics, radiographic parameters related to both sagittal and coronal alignment, and PROs were compared between the 2 groups.

RESULTS

There were 21 patients in the LCI and 80 in the non-LCI group. Compared with the non-LCI group, the LCI group was characterized by lower preoperative lumbar lordosis on sagittal alignment (38.3° vs 43.7°, p < 0.05), higher lumbar Cobb angle on coronal alignment (12.4° vs 5.1°, p < 0.05), and worse lumbar coronal balance (18.5 mm vs 6.8 mm, p < 0.05). After surgery, lumbar alignment in the sagittal and coronal planes was significantly improved in the LCI group, whereas no significant changes occurred in the non-LCI group. Scores on the preoperative Oswestry Disability Index and the visual analog scale for back pain and leg pain scores were significantly higher in the LCI group, whereas no differences were found between the 2 groups in the postoperative evaluation (p > 0.05).

CONCLUSIONS

DLS with LCI constitutes a distinct subgroup characterized by coronal malalignment and loss of whole lumbar lordosis, which may result in worse PROs. The TLIF procedure allows the reconstruction of the coronal and sagittal lumbar profile and achievement of satisfactory PROs.

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.

Five-year Reoperation Rates and Causes for Reoperations Following Lumbar Microendoscopic Discectomy and Decompression

STUDY DESIGN

Retrospective study of prospectively collected outcome data.

OBJECTIVE

The aim of this study was to investigate reoperation cases and determine whether or not the experience period of a single surgeon was associated with the causes of reoperations following lumbar microendoscopic discectomy for disc herniation (MEDH) and microendoscopic decompression for spinal stenosis (MEDS).

SUMMARY OF BACKGROUND DATA

There have been few studies that investigated reoperation cases following MEDH and MEDS.

METHODS

Between June 2005 (first experience of MEDH) and September 2013, the same surgeon had been using MEDH and/or MEDS on 441 consecutive patients. The follow-up rate was 89.3%. The causes and rates of reoperations (RORs) were determined at 5 years after the initial operations. We also investigated the experience period of a single surgeon (EPS, interval between June 2005 and initial operation: median, 37 months).

RESULTS

The 5-year reoperation rate for all patients combined was 12.4% (49/394). The main causes for reoperations were recurrence of disc herniation (ROR, 7.01%) and increase of postoperative spondylolisthesis and/or instability (ROR, 9/394 = 2.28%); two of the nine cases were caused by excessive decompression, and the EPSs were 11 and 16 months. The other causes for reoperations were postoperative epidural hematoma (ROR, 0.76%; median EPS, 20 months), insufficient decompression (ROR, 0.25%; EPS, 17 months), and residual segmental scoliosis (ROR, 7.69%); two segmental scoliosis cases did not provide relief from sciatica, and therefore L4/5 transforaminal interbody fusions were performed.

CONCLUSION

Postoperative epidural hematoma and excessive or insufficient decompression were often observed in the initial series of patients as the causes for reoperations. We think that it is important to be aware of and prevent such potential problems in any initial series of patients, as there are limitations to any surgical indications for the use of microendoscopic decompression for degenerative segmental scoliosis because of original traction and/or kinking of nerve roots.

LEVEL OF EVIDENCE

4.

The benefit zone of full-endoscopic spine surgery

Minimally invasive spine procedures have undergone rapid development during the last decade. Efforts to decrease muscle crush injuries during prolonged retraction, avoid significant soft tissue stripping and minimize bony resection are surgical principles that are employed to prevent iatrogenic instability and provide patients with decreased post-operative pain and disability. Full-endoscopic spine surgery represents a tool for the spine surgeon to provide targeted access to spinal pathology utilizing these principles. Endoscopic techniques have seen over 30 years of evolution and innovation, however, early iterations of these techniques largely focused on transforaminal lumbar microdiscectomies. Currently, endoscopic techniques are utilized for approaching pathology in the cervical, thoracic and lumbar spine. There has been a growing body of literature that not only confirms the efficacy of these procedures but also underscores the advantages these procedures offer with respect to less morbidity and safer complication profiles. Endoscopic decompressions have been utilized in the settings of degenerative spinal stenosis, spondylolisthesis, scoliosis, previous fusion, tumor and infection. Furthermore, endoscopic interbody fusion has also been utilized in the lumbar spine as technology continues to advance. As technological innovation continues to facilitate reproducible surgical technique and expand the indications for use, we believe that endoscopic spine surgical techniques will provide surgeons with a more powerful and less morbid approach to spinal pathology that ultimately elevates the standard of care when treating our patients. We present a brief review of the history of endoscopic spine surgery, an overview of current techniques and review current outcomes of endoscopic spine surgical procedures in the context of an invasiveness/complexity index to elucidate the benefit zone of these newer techniques.

Comparison of full-endoscopic and minimally invasive decompression for lumbar spinal stenosis in the setting of degenerative scoliosis and spondylolisthesis

OBJECTIVE

The management of lumbar spinal stenosis (LSS) with concurrent scoliosis and/or spondylolisthesis remains controversial. Full-endoscopic unilateral laminotomy for bilateral decompression (ULBD) facilitates neural decompression while preserving stabilizing osseoligamentous structures and may be uniquely suited for the treatment of LSS with concurrent mild to moderate degenerative deformity. The safety and efficacy of full-endoscopic versus minimally invasive surgery (MIS) ULBD in this patient population is studied here for the first time.

METHODS

A retrospective analysis of prospectively collected data was conducted on 45 consecutive LSS patients with concurrent scoliosis (≥ 10° coronal Cobb angle) and/or spondylolisthesis (≥ 3 mm). Patient demographics, operative details, complications, and imaging characteristics were reviewed. Outcomes were quantified using back and leg visual analog scale (VAS) scores and the Oswestry Disability Index (ODI) at 2 weeks, 3 months, and 1 year.

RESULTS

A total of 26 patients underwent full-endoscopic and 19 underwent MIS-ULBD with an average follow-up period of 12 months. The endoscopic cohort experienced a significantly shorter hospital length of stay (p = 0.014) and fewer adverse events (p = 0.010). Both cohorts experienced significant improvements in VAS and ODI scores at all time points (p < 0.001), but the endoscopic cohort demonstrated significantly better early ODI scores (p = 0.024).

CONCLUSIONS

Endoscopic and MIS-ULBD result in similar functional outcomes for LSS with mild to moderate deformity, while the endoscopic approach demonstrates a favorable rate of complications. Further studies are required to better delineate the characteristics of spinal deformities amenable to this approach and the durability of functional results.

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.