Laminectomy plus Fusion versus Laminectomy Alone for Lumbar Spondylolisthesis

Preoperative Association Between Quantitative Lumbar Muscle Parameters and Spinal Sagittal Alignment in Lumbar Fusion Patients

STUDY DESIGN

A retrospective cross-sectional study.

OBJECTIVE

To assess the association between spinal muscle morphology and spinopelvic parameters in lumbar fusion patients, with a special emphasis on lumbar lordosis (LL).

SUMMARY OF BACKGROUND DATA

Maintenance of sagittal alignment relies on muscle forces, but the basic association between spinal muscles and spinopelvic parameters is poorly understood.

MATERIALS AND METHODS

Patients operated between 2014 and 2017 who had both lumbar magnetic resonance imaging scan and standing whole-spine radiographs within six months before surgery were included. Muscle measurements were conducted on axial T2-weighted magnetic resonance images at the superior endplate L3-L5 for the psoas and L3-S1 for combined multifidus and erector spinae (paraspinal) muscles. A pixel intensity threshold method was used to calculate the total cross-sectional area (TCSA) and the functional cross-sectional area (FCSA). Spinopelvic parameters were measured on lateral standing whole-spine radiographs and included LL, pelvic incidence (PI), PI-LL mismatch, pelvic tilt, sacral slope, thoracic kyphosis, and sagittal vertical axis. Analyses were stratified by biological sex. Multivariable linear regression analyses with adjustments for age and body mass index (BMI) were performed.

RESULTS

A total of 104 patients (62.5% female) were included in the analysis. The patient population was 90.4% White with a median age at surgery of 69 years and a median BMI of 27.8 kg/m 2 . All muscle measurements were significantly smaller in women. PI, pelvic tilt, and thoracic kyphosis were significantly greater in women. PI-LL mismatch was 6.1° (10.6°) in men and 10.2° (13.5°) in women ( P =0.106), and sagittal vertical axis was 45.3 (40.8) mm in men and 35.7 (40.8) mm in women ( P =0.251). After adjusting for age and BMI, paraspinal TCSA at L3-L5, and paraspinal FCSA at L4 showed significant positive associations with LL in women. In men, psoas TCSA at L5 and psoas FCSA at L5 showed significant negative associations with LL, but none of the paraspinal muscle measurements.

CONCLUSION

Our findings indicate that psoas and lumbar spine extensor muscles interact differently on LL among men and women, creating a unique mechanical environment.

LEVEL OF EVIDENCE

Level 4.

A cost-utility analysis between decompression only and fusion surgery for elderly patients with lumbar spinal stenosis and sagittal imbalance

Lumbar spinal stenosis (LSS) and sagittal imbalance are relatively common in elderly patients. Although the goals of surgery include both functional and radiological improvements, the criteria of correction may be too strict for elderly patients. If the main symptom of patients is not forward-stooping but neurogenic claudication or pain, lumbar decompression without adding fusion procedure may be a surgical option. We performed cost-utility analysis between lumbar decompression and lumbar fusion surgery for those patients. Elderly patients (age > 60 years) who underwent 1-2 levels lumbar fusion surgery (F-group, n = 31) or decompression surgery (D-group, n = 40) for LSS with sagittal imbalance (C7 sagittal vertical axis, C7-SVA > 40 mm) with follow-up ≥ 2 years were included. Clinical outcomes (Euro-Quality of Life-5 Dimensions, EQ-5D; Oswestry Disability Index, ODI; numerical rating score of pain on the back and leg, NRS-B and NRS-L) and radiological parameters (C7-SVA; lumbar lordosis, LL; the difference between pelvic incidence and lumbar lordosis, PI-LL; pelvic tilt, PT) were assessed. The quality-adjusted life year (QALY) and incremental cost-effective ratio (ICER) were calculated from a utility score of EQ-5D. Postoperatively, both groups attained clinical and radiological improvement in all parameters, but NRS-L was more improved in the F-group (p = 0.048). ICER of F-group over D-group was 49,833 US dollars/QALY. Cost-effective lumbar decompression may be a recommendable surgical option for certain elderly patients, despite less improvement of leg pain than with fusion surgery.

Evaluating Instability in Degenerative Lumbar Spondylolisthesis: Objective Variables Versus Surgeon Impressions

The subjective degenerative spondylolisthesis instability classification (S-DSIC) system attempts to define preoperative instability associated with degenerative lumbar spondylolisthesis (DLS). The system guides surgical decision-making based on numerous indicators of instability that surgeons subjectively assess and incorporate. A more objective classification is warranted in order to decrease variation among surgeons. In this study, our objectives included (1) proposing an objective version of the DSIC system (O-DSIC) based on the best available clinical and biomechanical data and (2) comparing subjective surgeon perceptions (S-DSIC) with an objective measure (O-DSIC) of instability related to DLS.

METHODS

In this multicenter cohort study, we prospectively enrolled 408 consecutive adult patients who received surgery for symptomatic DLS. Surgeons prospectively categorized preoperative instability using the existing S-DSIC system. Subsequently, an O-DSIC system was created. Variables selected for inclusion were assigned point values based on previously determined evidence quality. DSIC types were derived by point summation: 0 to 2 points was considered stable, Type I); 3 points, potentially unstable, Type II; and 4 to 5 points, unstable, Type III. Surgeons' subjective perceptions of instability (S-DSIC) were retrospectively compared with O-DSIC types.

RESULTS

The O-DSIC system includes 5 variables: presence of facet effusion, disc height preservation (≥6.5 mm), translation (≥4 mm), a kyphotic or neutral disc angle in flexion, and low back pain (≥5 of 10 intensity). Type I (n = 176, 57.0%) and Type II (n = 164, 53.0%) were the most common DSIC types according to the O-DSIC and S-DSIC systems, respectively. Surgeons categorized higher degrees of instability with the S-DSIC than the O-DSIC system in 130 patients (42%) (p < 0.001). The assignment of DSIC types was not influenced by demographic variables with either system.

CONCLUSIONS

The O-DSIC system facilitates objective assessment of preoperative instability related to DLS. Surgeons assigned higher degrees of instability with the S-DSIC than the O-DSIC system in 42% of cases.

LEVEL OF EVIDENCE

Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

The efficacy of oral vitamin D supplements on fusion outcome in patients receiving elective lumbar spinal fusion—a randomized control trial

Background

Previous studies have reported that vitamin D supplement could improve fracture healing, but evidence regarding the role of vitamin D supplements in spinal fusion was limited. Thus, this study aimed to evaluate the effectiveness of oral vitamin D supplements on fusion outcomes in patients undergoing lumbar spinal fusion.

Methods

This randomized, double-blind, parallel-designed, active-control trial included the patients who planned for elective lumbar spinal fusion. Eligible patients were randomly assigned to receive either daily vitamin D3 (cholecalciferol) 800 IU and daily calcium citrate 600 mg (experimental group) or only daily calcium citrate 600 mg (control group). All supplements were given from postoperative day 1 and lasted for 3 months. Primary outcome was postoperative 1-year fusion rate, and secondary outcomes included time to fusion, Oswestry Disability Index (ODI), and visual analogue scale (VAS) for pain.

Results

Among the included 34 patients (21 in the experimental group and 13 in the control group), baseline 25-hydroxyvitamin D (25[OHVitD) level was 26.7 (10.4) ng/ml. Preoperative prevalence of vitamin D deficiency and insufficiency were 23.5% and 47.1%, respectively. Postoperative 1-year fusion rate was not significantly different between the two groups (95.2% vs. 84.6%, P = 0.544). The experimental group had significantly shorter time to fusion (Kaplan–Meier estimated: 169 days vs. 185 days [interquartile range: 88–182 days vs. 176–324 days], log-rank test: P = 0.028), lower postoperative 6-month ODI (P < 0.001), and lower postoperative 6-month VAS (P < 0.001) than the control group. Time to fusion was significantly and negatively correlated with preoperative, postoperative 3-month, and 6-month 25(OH)VitD levels (all P < 0.01).

Conclusion

The patient with vitamin D supplements had shorter time to fusion, better spinal function and less pain after elective spinal fusion. Further research is warranted to identify the patients who can benefit the most from vitamin D supplements and the appropriate dose of vitamin D supplements.

Trial registration

ClinicalTrials.gov, NCT05023122. Registered 20 August 2021. Retrospectively registered, http://clinicaltrials.gov/ct2/show/NCT03793530.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05948-9.

Minimally Invasive Facetectomy and Fusion for Resection of Extensive Dumbbell Tumors in the Lumbar Spine

Background and Objectives: Resection of dumbbell tumors can be challenging, and facet joint sparing approaches carry the risk of incomplete resection. In contrast, additional facetectomy may allow better surgical exposure at the cost of spinal stability. The aim of this study is to compare facet-sparing and facetectomy approaches for the treatment of lumbar spine dumbbell tumors. Materials and Methods: In a cohort study setting, we analyzed Eden type 2 and 3 tumors operated in our department. Conventional facet-sparing microsurgical or facetectomy approaches with minimally invasive fusions were performed according to individual surgeons’ preference. Primary outcomes were extent of resection and tumor progression over time. Secondary outcomes were perioperative adverse events. Results: Nineteen patients were included. Nine patients were operated on using a facet-sparing technique. Ten patients underwent facetectomy and fusion. While only one patient (11%) in the facet-sparing group experienced gross total resection (GTR), this was achieved for all patients in the facetectomy group (100%). The relative risk (RR) for incomplete resection in the facet-sparing cohort was 18.7 (95% CI 1.23–284.047; p = 0.035). In addition, time to progression was shorter in the facet-sparing cohort (p = 0.022) and all patients with a residual tumor underwent a second resection after a median follow-up time of 42 months (IQR 25–66). Conclusions: Minimally invasive resection of lumbar Eden type 2 and 3 dumbbell tumors including facetectomy in combination with instrumentation appears to be safe and superior to the facet-sparing approach in terms of local tumor control.

Development and validation of machine learning-based predictive model for clinical outcome of decompression surgery for lumbar spinal canal stenosis

BACKGROUND CONTEXT

Although the results of decompression surgery for lumbar spinal canal stenosis (LSS) are favorable, it is still difficult to predict the postoperative health-related quality of life of patients before surgery.

PURPOSE

The purpose of this study was to develop and validate a machine learning model to predict the postoperative outcome of decompression surgery for patients with LSS.

STUDY DESIGN/SETTING

A multicentered retrospective study.

PATIENT SAMPLE

A total of 848 patients who underwent decompression surgery for LSS at an academic hospital, tertiary center, and private hospital were included (age 71±9 years, 68% male, 91% LSS, level treated 1.8±0.8, operation time 69±37 minutes, blood loss 48±113 mL, and length of hospital stay 12±5 days).

OUTCOME MEASURES

Baseline and 2 years postoperative health-related quality of life.

METHODS

The subjects were randomly assigned in a 7:3 ratio to a model building cohort and a testing cohort to test the models' accuracy. Twelve predictive algorithms using 68 preoperative factors were used to predict each domain of the Japanese Orthopedic Association Back Pain Evaluation Questionnaire and visual analog scale scores at 2 years postoperatively. The final predictive values were generated using an ensemble of the top five algorithms in prediction accuracy.

RESULTS

The correlation coefficients of the top algorithms for each domain established using the preoperative factors were excellent (correlation coefficient: 0.95-0.97 [relative error: 0.06-0.14]). The performance evaluation of each Japanese Orthopedic Association Back Pain Evaluation Questionnaire domain and visual analog scale score by the ensemble of the top five algorithms in the testing cohort was favorable (mean absolute error [MAE] 8.9-17.4, median difference [MD] 8.1-15.6/100 points), with the highest accuracy for mental status (MAE 8.9, MD 8.1) and the lowest for buttock and leg numbness (MAE 1.7, MD 1.6/10 points). A strong linear correlation was observed between the predicted and measured values (linear correlation 0.82-0.89), while 4% to 6% of the subjects had predicted values of greater than±3 standard deviations of the MAE.

CONCLUSIONS

We successfully developed a machine learning model to predict the postoperative outcomes of decompression surgery for patients with LSS using patient data from three different institutions in three different settings. Thorough analyses for the subjects with deviations from the actual measured values may further improve the predictive probability of this model.

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.

The type of cervical disc herniation on MRI does not correlate to clinical outcomes

AIMS

The aim of this study was to investigate whether the type of cervical disc herniation influences the severity of symptoms at the time of presentation, and the outcome after surgical treatment.

METHODS

The type and extent of disc herniation at the time of presentation in 108 patients who underwent anterior discectomy for cervical radiculopathy were analyzed on MRI, using a four-point scale. These were dichotomized into disc bulge and disc herniation groups. Clinical outcomes were evaluated using the Neck Disability Index (NDI), 36-Item Short Form Survey (SF-36), and a visual analogue scale (VAS) for pain in the neck and arm at baseline and two years postoperatively. The perceived recovery was also assessed at this time.

RESULTS

At baseline, 46 patients had a disc bulge and 62 had a herniation. There was no significant difference in the mean NDI and SF-36 between the two groups at baseline. Those in the disc bulge group had a mean NDI of 44.6 (SD 15.2) compared with 43.8 (SD 16.0) in the herniation group (p = 0.799), and a mean SF-36 of 59.2 (SD 6.9) compared with 59.4 (SD 7.7) (p = 0.895). Likewise, there was no significant difference in the incidence of disabling arm pain in the disc bulge and herniation groups (84% vs 73%; p = 0.163), and no significant difference in the incidence of disabling neck pain in the two groups (70.5% (n = 31) vs 63% (n = 39); p = 0.491). At two years after surgery, no significant difference was found in any of the clinical parameters between the two groups.

CONCLUSION

In patients with cervical radiculopathy, the type and extent of disc herniation measured on MRI prior to surgery correlated neither to the severity of the symptoms at presentation, nor to clinical outcomes at two years postoperatively.Cite this article: Bone Joint J 2022;104-B(11):1242-1248.

Minimally Invasive Lumbar Decompression Versus Minimally Invasive Transforaminal Lumbar Interbody Fusion for Treatment of Low-Grade Lumbar Degenerative Spondylolisthesis

STUDY DESIGN

A retrospective cohort comparison study.

OBJECTIVE

To compare perioperative outcomes, radiographic parameters, and patient-reported outcome measures (PROMs) between minimally invasive unilateral laminotomy with bilateral decompression (MIS-ULBD) versus MIS transforaminal lumbar interbody fusion (MIS-TLIF) for treatment of low-grade lumbar degenerative spondylolisthesis.

SUMMARY OF BACKGROUND DATA

While lumbar degenerative spondylolisthesis is a common condition, optimal surgical treatment remains controversial. Newer MIS techniques, which preserve bone, paraspinal musculature, and posterior midline stabilizers, are thought to reduce the risk of iatrogenic instability and may obviate the need for fusion. However, few comparative studies of MIS techniques for low-grade lumbar degenerative spondylolisthesis currently exist.

MATERIALS AND METHODS

Consecutive patients with low-grade (Meyerding grade I or II) lumbar degenerative spondylolisthesis treated with single-level MIS-ULBD or MIS-TLIF were identified retrospectively from a prospectively collected spine surgery registry from April 2017 to November 2021. Perioperative outcomes, radiographic data, and PROMs were assessed.

RESULTS

A total of 188 patients underwent either MIS-ULBD or MIS-TLIF (79 MIS-ULBD and 109 MIS-TLIF). Patients who underwent MIS-ULBD tended to be older, had higher Charlson Comorbidity Index, lower mean percentage back pain, higher percentage of L4/L5 pathology, shorter operative time, lower estimated blood loss, and lower postoperative pain ( P <0.05). In both groups, there were statistically significant improvements at one year for five of the six PROMs studied: Oswestry Disability Index (ODI), visual analog scale (VAS)-back pain, VAS-leg pain, Short Form 12 Physical Component Score (SF12-PCS), and Patient-Reported Outcomes Measurement Information System (PROMIS) ( P <0.05). On multivariate analysis controlling for confounders, there were no associations between procedure type and achieving minimal clinically important difference at one year in any of the PROMs studied.

CONCLUSIONS

The current study suggests that both MIS-ULBD and MIS-TLIF result in significant improvements in pain and physical function for patients with low-grade lumbar degenerative spondylolisthesis.

LEVEL OF EVIDENCES

3.

Current treatment and decision-making factors leading to fusion vs decompression for one-level degenerative spondylolisthesis: survey results from members of the Lumbar Spine Research Society and Society of Minimally Invasive Spine Surgery

BACKGROUND

Degenerative spondylolisthesis (DS) is one of the most common pathologies spine surgeons treat. While a number of potential factors have been identified, there is no current consensus on which variables most impact the decision to fuse vs. decompress alone in this population.

PURPOSE

The purpose of this study was to describe current DS treatment practices and identify both the radiographic and clinical factors leading to the decision to fuse segments for one level DS.

STUDY DESIGN/SETTING

Descriptive cross-sectional survey.

PATIENT SAMPLE

Surveys were administered to members of Lumbar Spine Research Society and Society of Minimally Invasive Spine Surgery.

OUTCOME MEASURES

Surgeon demographics and treatment practices were reported. Radiographic and clinical parameters were ranked by each surgeon with regards to their importance.

METHODS

The primary analysis was limited to completed surveys. Baseline characteristics were summarized. Clinical and radiographic parameters were ranked and compared. Ranking of each clinical and radiographic parameters was reported using best and worst rank, mean rank position, and percentiles. The most important, top 3 most important, and top 5 most important parameters were ordered given each parameter's ranking frequency.

RESULTS

381 surveys were returned completed. With regards to fusion vs. decompression, 19.9% fuse all cases, 39.1% fuse > 75%, 17.8% fuse 50%-75%, and 23.2% fuse <25%. The most common decompressive technique was a partial laminotomy (51.4%), followed by full laminectomy (28.9%). 82.2% of respondents instrument all fusion cases. Instability (93.2%), spondylolisthesis grade (59.8%), and laterolisthesis (37.3%) were the most common radiographic factors impacting the decision to fuse. With regards to the clinical factors leading to fusion, mechanical low back pain (83.2%), activity level (58.3%), and neurogenic claudication (42.8%) were the top 3 clinical parameters.

CONCLUSIONS

There is little consensus on the treatment of DS, with society members showing substantial variation in treatment patterns with the majority utilizing fusion for treatment. The most common radiographic parameters impacting treatment are instability, spondylolisthesis grade, and laterolisthesis while mechanical low back pain, activity level, and neurogenic claudication are the most common clinical parameters.

Systematic review and meta-analysis for the impact of rod materials and sizes in the surgical treatment of adult spine deformity

PURPOSE

To assess clinical and safety outcomes associated with different rod materials and diameters in adult spinal deformity (ASD) surgery.

METHODS

A systematic literature review and meta-analysis evaluated ASD surgery using pedicle screw fixation systems with rods of different materials and sizes. Postoperative outcomes (i.e., Cobb, sagittal vertical axis, and pelvic tilt angle) and complications (i.e., pseudarthrosis and rod breakage) were assessed. Random effects models (REMs) pooled data for outcomes reported in ≥ 2 studies.

RESULTS

Among 50 studies evaluating ASD surgery using pedicle screw fixation systems, 17 described rod material/diameter. Postoperative outcomes did not statistically differ between cobalt-chromium (CoCr) vs. titanium (Ti) rods (n = 2 studies; mean [95% confidence interval (CI)] sagittal vertical axis angle: CoCr 37.00° [18.58°-55.42°] and Ti 32.58° [24.62°-40.54°]; mean [95% CI] pelvic tilt angle: CoCr 26.20° [22.87°-29.53°] and Ti 20.15° [18.0°-22.31°]). The pooled proportion (95% CI) of pseudarthrosis was 15% (7-22%) for CoCr and 12% (- 8-32%) for stainless steel (SS) (n = 2 studies each; Chi2 = 0.07, p = 0.79). The pooled proportion (95% CI) of broken rods was 12% (1-22%) for Ti (n = 3 studies) and 10% (2-19) for CoCr (n = 1 study). Among 6.0-6.35 mm rods, the pooled (95% CI) postoperative Cobb angle (n = 2) was 12.01° (9.75°-14.28°), sagittal vertical axis angle (n = 4) was 35.32° (30.02°-40.62°), and pelvic tilt angle was 21.11° (18.35°-23.86°).

CONCLUSIONS

For ASD patients undergoing posterior fixation and fusion, there are no statistically significant differences in postoperative outcomes or complications among rods of varying materials and diameters. Benchmark postsurgical outcomes and complication rates by rod material and diameter are provided.

LEVEL OF EVIDENCE

III.

Surgical outcomes between posterior decompression alone and posterior decompression with fusion surgery among patients with Meyerding grade 2 degenerative spondylolisthesis: a multicenter cohort study

Background

Whether lumbar decompression with fusion surgery is effective against Meyerding grade 2 degenerative spondylolisthesis (DS) is unknown. Therefore, the current study aimed to compare the surgical outcomes between posterior decompression alone and posterior decompression with fusion surgery among patients with grade 2 DS with central canal stenosis.

Methods

This retrospective cohort study included prospectively registered patients (n = 3863) who underwent surgery for degenerative lumbar spinal canal stenosis at nine high-volume spine centers from April 2017 to July 2019. Patients with grade 2 DS and central canal stenosis were included in the analysis. Patients with radiculopathy, including foraminal stenosis, degenerative scoliosis, and concomitant anterior spinal fusion, and those with a previous history of lumbar surgery were excluded. The participants were divided into the decompression alone group (group D) and decompression with fusion surgery group (group F). Data about patient-reported outcomes, including Numeric Rating Scale (low back pain, leg pain, leg numbness, and foot numbness), Oswestry Disability Index, EuroQol Five-Dimensional questionnaire, and 12-Item Short-Form Health Survey scores, were obtained preoperatively and 2 years postoperatively.

Results

In total, 2354 (61%) patients, including 42 (1.8%) with grade 2 DS (n = 18 in group D and n = 24 in group F), completed the 2-year follow-up. Group D had a higher proportion of female patients than group F. However, the two groups did not significantly differ in terms of other baseline demographic characteristics. Group D had a significantly shorter surgical time and lower volume of intraoperative blood loss than group F. Postoperative patient-reported outcomes did not significantly differ between the two groups, although the preoperative degree of low back pain was higher in group F than in group D. The slip degree of group D did not worsen during the follow-up period.

Conclusion

The surgical outcomes were similar regardless of the addition of fusion surgery among patients with grade 2 DS. Decompression alone was superior to decompression with fusion surgery as it was associated with a lower volume of intraoperative blood loss and shorter surgical time.

Characteristics and outcomes of patients undergoing lumbar spine surgery for axial back pain in the Michigan Spine Surgery Improvement Collaborative

BACKGROUND CONTEXT

The indications for surgical intervention of axial back pain without leg pain for degenerative lumbar disorders have been limited in the literature, as most study designs allow some degree of leg symptoms in the inclusion criteria.

PURPOSE

To determine the outcome of surgery (decompression only vs. fusion) for pure axial back pain without leg pain.

STUDY DESIGN/SETTING

Prospectively collected data in the Michigan Spine Surgery Improvement Collaborative (MSSIC).

PATIENT SAMPLE

Patients with pure axial back pain without leg pain underwent lumbar spine surgery for primary diagnoses of lumbar disc herniation, lumbar stenosis, and isthmic or degenerative spondylolisthesis ≤ grade II.

OUTCOME MEASURES

Minimally clinically important difference (MCID) for back pain, Numeric Rating Scale of back pain, Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF), MCID of PROMIS-PF, and patient satisfaction on the North American Spine Surgery Patient Satisfaction Index were collected at 90 days, 1 year, and 2 years after surgery.

METHODS

Log-Poisson generalized estimating equation models were constructed with patient-reported outcomes as the independent variable, reporting adjusted risk ratios (RR_adj).

RESULTS

Of the 388 patients at 90 days, multi-level versus single level lumbar surgery decreased the likelihood of obtaining a MCID in back pain by 15% (RR_adj=0.85, p=.038). For every one-unit increase in preoperative back pain, the likelihood for a favorable outcome increased by 8% (RR_adj=1.08, p<.001). Of the 326 patients at 1 year, symptom duration > 1 year decreased the likelihood of a MCID in back pain by 16% (RR_adj=0.84, p=.041). The probability of obtaining a MCID in back pain increased by 9% (RR_adj=1.09, p<.001) for every 1-unit increase in baseline back pain score and by 14% for fusions versus decompression alone (RR_adj=1.14, p=.0362). Of the 283 patients at 2 years, the likelihood of obtaining MCID in back pain decreased by 30% for patients with depression (RR_adj=0.70, p<.001) and increased by 8% with every one-unit increase in baseline back pain score (RR_adj=1.08, p<.001).

CONCLUSIONS

Only the severity of preoperative back pain was associated with improvement in MCID in back pain at all time points, suggesting that surgery should be considered for selected patients with severe axial pain without leg pain. Fusion surgery versus decompression alone was associated with improved patient-reported outcomes at 1 year only, but not at the other time points.

Five-Year Outcomes After Decompression and Fusion Versus Decompression Alone in the Treatment of Lumbar Synovial Cysts

BACKGROUND

Spinal synovial cysts are acquired, fluid-filled lesions of the facet joint that most commonly occur in the lumbar spine. They are thought to arise from degenerative changes and to result from segmental instability. Although the treatment of these lesions has been studied, the long-term implications and effects of the different strategies for surgical intervention (i.e., decompression and fusion vs. decompression alone) have not yet been elucidated or established.

METHODS

Using an all-payer database with 53 million patient records (MARINER-53), patients with a diagnosis of lumbar synovial cysts were identified. Patients who had undergone lumbar fusion versus laminectomy were matched 1:1 using binomial and gaussian logistic regression models to evaluate the need for future lumbar surgery within 5 years after their index procedure.

RESULTS

No statistically significant differences were noted between the 5-year rates of subsequent intervention, additional laminectomy, or fusion among patients who had undergone index decompression and fusion (n = 51; 10.5%) versus decompression alone (n = 43; 8.8%; P = 0.39). Furthermore, no significant differences were found in the odds of intervention type after index decompression and fusion versus decompression alone (subsequent laminectomy: odds ratio, 0.59; 95% confidence interval, 0.32-1.09; subsequent fusion: odds ratio, 1.14; 95% confidence interval, 0.64-2.02).

CONCLUSIONS

Patient-specific factors and surgeon-patient-shared decision-making should be used when planning interventions for these lesions. However, synovial cysts might not require a fusion procedure for presumed instability. Further investigation is required, using randomized and prospective studies, to further evaluate the effective treatment of this entity.

Degenerative Lumbar Spondylolisthesis Patients With Movement-related Low Back Pain Have Less Postoperative Satisfaction After Decompression Alone

STUDY DESIGN

Retrospective analysis of prospectively collected multicenter observational data.

OBJECTIVE

The aim was to examine the preoperative factors affecting postoperative satisfaction following posterior lumbar interbody fusion (PLIF) and microendoscopic muscle-preserving interlaminar decompression (ME-MILD) in patients with degenerative lumbar spondylolisthesis (DLS).

SUMMARY OF BACKGROUND DATA

The technique involved in DLS surgery may either be decompression alone or decompression-fixation. Poor performance may occur after either of these surgical treatments. The author hypothesized that evaluating the correlation between preoperative quality of life and postoperative performance would aid in determining the optimal procedure.

MATERIALS AND METHODS

This study included 138 patients who underwent surgery for 1-level mild DLS. The authors performed PLIF for 79 patients and ME-MILD for 59 patients. When the satisfaction subscale of the Zurich Claudication Questionnaire exceeded 2 points, postoperative satisfaction was considered poor. The clinical characteristics were investigated. Responses to preoperative health-related quality of life questionnaires, such as the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ), short form-36 health survey (SF-36), and visual analog scale, were compared between the satisfied and unsatisfied groups.

RESULTS

In the PLIF group, no endogenous factors influenced postoperative satisfaction. The ME-MILD cohort's satisfied and unsatisfied patients differed significantly in terms of preoperative lumbar spine dysfunction ( P <0.001) items of the JOABPEQ, role physical ( P =0.03), and role emotional ( P =0.03) items of the SF-36. A strong correlation ( r =-0.609 P =0.015) was found between preoperative lumbar spine dysfunction and postoperative satisfaction.

CONCLUSIONS

In the ME-MILD group, preoperative lumbar spine function was correlated with postoperative satisfaction. Decompression alone may be ineffective in cases with decreased lumbar spine function prior to surgery. The degree of low back pain on movement should be considered before selecting the surgical method.

LEVEL OF EVIDENCE

3.

Utility of a fulcrum for positioning support during flexion-extension radiographs for assessment of lumbar instability in patients with degenerative lumbar spondylolisthesis

OBJECTIVE

The authors investigated a new standardized technique for evaluating lumbar stability in lumbar lateral flexion-extension (LFE) radiographs. For patients with lumbar spondylolisthesis, a three-part fulcrum with a support platform that included a semiarc leaning tool with armrests, a lifting platform for height adjustment, and a base for stability were used. Standard functional radiographs were used for comparison to determine whether adequate flexion-extension was acquired through use of the fulcrum method.

METHODS

A total of 67 consecutive patients diagnosed with L4-5 degenerative lumbar spondylolisthesis were enrolled in the study. The authors analyzed LFE radiographs taken with the patient supported by a fulcrum (LFEF) and without a fulcrum. Sagittal translation (ST), segmental angulation (SA), posterior opening (PO), change in lumbar lordosis (CLL), and lumbar instability (LI) were measured for comparison using functional radiographs.

RESULTS

The average value of SA was 5.76° ± 3.72° in LFE and 9.96° ± 4.00° in LFEF radiographs, with a significant difference between them (p < 0.05). ST and PO were also significantly greater in LFEF than in LFE. The detection rate of instability was 10.4% in LFE and 31.3% in LFEF, and the difference was significant. The CLL was 27.31° ± 11.96° in LFE and 37.07° ± 12.963.16° in LFEF, with a significant difference between these values (p < 0.05).

CONCLUSIONS

Compared with traditional LFE radiographs, the LFEF radiographs significantly improved the detection rate of LI. In addition, this method may reduce patient discomfort during the process of obtaining radiographs.

Lumbar dynamic pedicle-based stabilization versus fusion in degenerative disease: a multicenter, double-blind, prospective, randomized controlled trial

OBJECTIVE

Fusion is the standard of treatment for degenerative lumbar symptomatic instabilities. Dynamic stabilization is a potential alternative, with the aim of reducing pathological motion. Potential advantages are a reduction of surgical complexity and morbidity. The aim of this study was to assess whether dynamic stabilization is associated with a higher degree of functional improvement while reducing surgical complexity and thereby surgical duration and perioperative complications in comparison with lumbar fusion.

METHODS

This was a multicenter, double-blind, prospective, randomized, 2-arm superiority trial. Patients with symptomatic mono- or bisegmental lumbar degenerative disease with or without stenosis and instability were randomized 1:1 to instrumented fusion or pedicle-based dynamic stabilization. Patients underwent either rigid internal fixation and interbody fusion or pedicle-based dynamic stabilization. The primary endpoint was the Oswestry Disability Index (ODI) score, and secondary endpoints were pain, health-related quality of life, and patient satisfaction at 24 months.

RESULTS

Of 293 patients randomized to fusion or dynamic stabilization, 269 were available for analysis. The duration of surgery was significantly shorter for dynamic stabilization versus fusion, and the blood loss was significantly less for dynamic stabilization (380 ml vs 506 ml). Assessment of primary and secondary outcome parameters revealed no significant differences between groups. There were no differences in the incidence of adverse events.

CONCLUSIONS

Dynamic pedicle-based stabilization can achieve similar clinical outcome as fusion in the treatment of lumbar degenerative instabilities. Secondary failures are not different between groups. However, dynamic stabilization is less complex than fusion and is a feasible alternative.

Cognitive Processes during Recovery: Moving toward Personalized Spine Surgery Outcomes

This paper focuses on a novel application of personalized medicine: the ways one thinks about health (i.e., appraisal processes) as relevant predictors of spine-surgery response. This prospective longitudinal cohort study (n = 235) investigated how appraisal processes relate to outcomes of spinal decompression and/or fusion surgery, from pre-surgery through one-year post-surgery. Patient-reported outcomes assessed spine-specific disability (Oswestry Disability Index (ODI)), mental health functioning (Rand-36 Mental Component Score (MCS)), and cognitive appraisal processes (how people recall past experiences and to whom they compare themselves). Analysis of Variance examined the appraisal-outcomes association in separate models at pre-surgery, 3 months, and 12 months. We found that appraisal processes explained less variance at pre-surgery than later and were differentially relevant to health outcomes at different times in the spine-surgery recovery trajectory. For the ODI, recall of the seriousness of their condition was most prominent early in recovery, and comparing themselves to positive standards was most prominent later. For the MCS, not focusing on the negative aspects of their condition and/or on how others see them was associated with steady improvement and higher scores at 12 months. Appraisal processes are relevant to both spine-specific disability and mental-health functioning. Such processes are modifiable objects of attention for personalizing spine-surgery outcomes.

Clinical Application of Large Channel Endoscopic Systems with Full Endoscopic Visualization Technique in Lumbar Central Spinal Stenosis: A Retrospective Cohort Study

INTRODUCTION

Recently, large channel endoscopic systems and full endoscopic visualization technique have been used to perform unilateral laminotomy for bilateral decompression (ULBD) treatment for lumbar central spinal stenosis (LCSS). However, various endoscopic systems possess different design parameters, which may affect the technical points and treatment outcomes. The object of this retrospective study was to compare the efficiency, safety, and effectiveness of ULBD under the iLESSYS Delta system versus the Endo-Surgi Plus system.

METHODS

In the period from October 2020 to April 2021, ULBD was performed using the iLESSYS Delta system or Endo-Surgi Plus system to treat LCSS. Patients were classified into two groups based on the endoscopy system employed. Patient demographics, perioperative indexes, complications, and imaging characteristics were reviewed. Clinical outcomes were quantified using back and leg visual analog scale (VAS) scores and Oswestry Disability Index (ODI) at the time points of follow-up.

RESULTS

Thirty-two patients were assigned to the iLESSYS Delta system group and 37 to the Endo-Surgi Plus system group. In the comparison between the two groups, the Endo-Surgi Plus system possessed a shorter incision length and operation time (p < 0.005), and no statistical differences in other aspects were observed. The dural sacs of both groups were significantly expanded postoperatively compared to preoperatively (p < 0.001). Both groups experienced improvements in VAS and ODI scores at all time points (p < 0.001) and equally low frequency of complications.

CONCLUSIONS

Current research suggests that both the Endo-Surgi Plus system and iLESSYS Delta system achieved favorable high safety and clinical outcomes in ULBD for treatment of LCSS. The use of a fully visualized trephine may have increased the efficiency of the Endo-Surgi Plus system. Moreover, the Endo-Surgi Plus system may be associated with a wider decompression range and indications.

Decompression alone or decompression and fusion in degenerative lumbar spondylolisthesis

BACKGROUND

Clinically, there are substantive practice variations in surgical management of degenerative lumbar spondylolisthesis. We aimed at evaluating whether decompression alone outcomes for patients with degenerative lumbar spondylolisthesis are comparable to those of decompression with fusion.

METHODS

In this meta-analysis, the Embase, PubMed, and Cochrane Library databases were searched from inception to February 16th, 2022. Randomised controlled trials (RCTs) and cohort studies comparing decompression alone with decompression and fusion for patients with degenerative lumbar spondylolisthesis were included in this study. There were no language limitations. Odds ratio (OR), mean difference (MD) and 95% confidence interval (CI) were used to report results in the random-effects model. Main outcomes included Oswestry disability index (ODI), pain, clinical satisfaction, complication and reoperation rates. The study protocol was published in PROSPERO (CRD42022310645).

FINDINGS

Thirty-three studies (6 RCTs and 27 cohort studies) involving 94 953 participants were included. Differences in post-operative ODI between decompression alone and decompression with fusion were not significant. A small difference for back (MD, 0.13; [95% CI, 0.08 to 0.18]; I ²:0.00%) and leg pain (MD, 0.30; [95% CI, 0.09 to 0.51]; I ²:48.35%) was observed on the 3rd post-operative month. The results did not reveal significant differences in leg pain and back pain between decompression alone and fusion groups on the 6th, 12th, and 24th post-operative months. Difference in clinical satisfaction between decompression alone and decompression with fusion were not significant from RCTs (OR, 0.26; [95% CI, 0.03 to 1.92]; I ²:83.27%). Complications (OR, 1.54; [95% CI, 1.16 to 2.05]; I ²:48.88%), operation time (MD, 83.39; [95% CI, 55.93 to 110.85]; I ²:98.75%), intra-operative blood loss (MD, 264.58; [95% CI, 174.99 to 354.16]; I ²:95.61%) and length of hospital stay (MD, 2.85; [95% CI, 1.60 to 4.10]; I ²:99.49%) were higher with fusion.

INTERPRETATION

Clinical effectiveness of decompression alone was comparable to that of decompression with fusion for degenerative lumbar spondylolisthesis. Decompression alone is recommended for patients with degenerative lumbar spondylolisthesis.

FUNDING

This work was supported by grants from the National Natural Science Foundation of China (No. 81871818), Tangdu Hospital Seed Talent Program (Fei-Long Wei), Natural Science Basic Research Plan in Shaanxi Province of China (No.2019JM-265) and Social Talent Fund of Tangdu Hospital (No.2021SHRC034).

Radiographic Analysis of Pedicle Screw Retractor-Assisted Transforaminal Lumbar Interbody Fusion for Single-Segment Spondylolisthesis in Adults: A Retrospective Study and Technical Note

Objectives

The objective of this study was to introduce a retractor that can be temporarily installed on unilateral pedicle screws to achieve distraction‐reduction and nerve root protection, and to analyze the efficacy and safety of retractor‐assisted transforaminal lumbar interbody fusion (TLIF) in the treatment of lumbar spondylolisthesis.

Methods

This was a retrospective study of 125 patients who underwent retractor‐assisted TLIF for single‐segment spondylolisthesis from November 2017 to February 2021. Based on morphology, patients were divided into degenerative (N = 66) and isthmic groups (N = 59). Differences in demographics and preoperative characteristics between the groups were analyzed using the independent samples t‐test and χ² test. Changes in radiographic parameters (disc height, foramen height, spondylolisthesis degree, slippage length, and segmental lordosis) before and after surgery were compared using the paired samples t‐test. Logistic regression analysis was performed to analyze the relationship between facet joint angle (FJA) and degenerative lumbar spondylolisthesis (DLS).

Results

Unilateral screw retractor‐assisted TLIF significantly corrected spondylolisthesis and improved disc height and segmental lordosis (p < 0.05). There was no significant difference in foramen height between the two sides before and after operation (pre: 15.81 ± 3.58 mm vs 15.69 ± 3.68 mm, p = 0.599; post: 18.65 ± 2.31 mm vs 18.74 ± 2.26 mm, p = 0.516). The degree of spondylolisthesis in the DLS group before surgery was significantly lower than that in the isthmic spondylolisthesis group (17.70 ± 5.62% vs 25.18 ± 9.73%, p < 0.001), whereas a similar degree of correction could be achieved after surgery (5.91 ± 3.12% vs 7.16 ± 5.69%, p = 0.135). FJAs from L3/4 to L5/S1 were significantly smaller in patients with DLS than those in with isthmic spondylolisthesis (p < 0.05). Patients with facet sagittalization were more likely to have DLS (β: −0.101, odds ratio [OR]:0.904, 95% confidence interval [CI]: 0.874–0.934, p < 0.001), while the cut‐off FJA of L4/5 for predicting L4 spondylolisthesis was 53.19.

Conclusions

Pedicle screw retractor‐assisted TLIF is effective and safe in treating both degenerative and isthmic lumbar spondylolisthesis. The unilateral retractor has the capacity to maintain the disc height achieved by paddle distractors, which optimizes the nerve protection and distractor placement. Patients with an FJA on L4/5 <53.19 were more likely to have DLS.

Preoperative Patient-reported Outcomes are not Associated With Sagittal and Spinopelvic Alignment in Degenerative Lumbar Spondylolisthesis

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

The aim of this study was to evaluate whether sagittal and spinopelvic alignment correlate with preoperative patient-reported outcomes (PROs) in degenerative lumbar spondylolisthesis (DLS) with spinal stenosis.

SUMMARY OF BACKGROUND DATA

Positive global sagittal balance and spinopelvic malalignment are strongly correlated with symptom severity in adult spinal deformity, but this correlation has not been evaluated in DLS.

METHODS

Patients were enrolled in the Canadian Spine Outcomes Research Network (CSORN) prospective DLS study at seven centers between January 2015 and May 2018. Correlation was assessed between the following preoperative PROs: Oswestry Disability Index (ODI), numeric rating scale (NRS) leg pain, and NRS back pain and the following preoperative sagittal radiographic parameters SS, PT, PI, SVA, LL, TK, T1SPI, T9SPI, and PI-LL. Patients were further divided into groups based on spinopelvic alignment: Group 1 PI-LL<10°; Group 2 PI-LL ≥10° with PT <30°; and Group 3 PI-LL ≥10° with PT ≥30°. Preoperative PROs were compared among these three groups and were further stratified by those with SVA <50 mm and SVA ≥50 mm.

RESULTS

A total of 320 patients (61% female) with mean age of 66.1 years were included. Mean (SD) preoperative PROs were: NRS leg pain 7.4 (2.1), NRS back pain 7.1 (2.0), and ODI 45.5 (14.5). Preoperative radiographic parameters included: SVA 27.1 (33.4) mm, LL 45.7 (13.4°), PI 57.6 (11.9), and PI-LL 11.8 (14.0°). Weak but statistically significant correlations were observed between leg pain and PT (r = -0.114) and PI (ρ = -0.130), and T9SPI with back pain ( r  = 0.130). No significant differences were observed among the three groups stratified by PI-LL and PT. No significant differences in PROs were observed between patients with SVA <50 mm compared to those with SVA ≥50 mm.

CONCLUSION

Sagittal and spinopelvic malalignment do not appear to significantly influence baseline PROs in patients with DLS.

LEVEL OF EVIDENCE

Prognostic level II.

Incidence of Revision Surgery After Decompression With vs Without Fusion Among Patients With Degenerative Lumbar Spinal Stenosis

IMPORTANCE

Only limited data derived from large prospective cohort studies exist on the incidence of revision surgery among patients who undergo operations for degenerative lumbar spinal stenosis (DLSS).

OBJECTIVE

To assess the cumulative incidence of revision surgery after 2 types of index operations-decompression alone or decompression with fusion-among patients with DLSS.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study analyzed data from a multicenter, prospective cohort study, the Lumbar Stenosis Outcome Study, which included patients aged 50 years or older with DLSS at 8 spine surgery and rheumatology units in Switzerland between December 2010 and December 2015. The follow-up period was 3 years. Data for this study were analyzed between October and November 2021.

EXPOSURES

All patients underwent either decompression surgery alone or decompression with fusion surgery for DLSS.

MAIN OUTCOMES AND MEASURES

The primary outcome was the cumulative incidence of revision operations. Secondary outcomes included changes in the following patient-reported outcome measures: Spinal Stenosis Measure (SSM) symptom severity (higher scores indicate more pain) and physical function (higher scores indicate more disability) subscale scores and the EuroQol Health-Related Quality of Life 5-Dimension 3-Level questionnaire (EQ-5D-3L) summary index score (lower scores indicate worse quality of life).

RESULTS

A total of 328 patients (165 [50.3%] men; median age, 73.0 years [IQR, 66.0-78.0 years]) were included in the analysis. Of these, 256 (78.0%) underwent decompression alone and 72 (22.0%) underwent decompression with fusion. The cumulative incidence of revisions after 3 years of follow-up was 11.3% (95% CI, 7.4%-15.1%) for the decompression alone group and 13.9% (95% CI, 5.5%-21.5%) for the fusion group (log-rank P = .60). There was no significant difference in the need for revision between the 2 groups over time (unadjusted absolute risk difference, 2.6% [95% CI, -6.3% to 11.4%]; adjusted absolute risk difference, 3.9% [95% CI, -5.2% to 17.0%]; adjusted hazard ratio, 1.40 [95% CI, 0.63-3.13]). The number of revisions was significantly associated with higher SSM symptom severity scores (β, 0.171; 95% CI, 0.047-0.295; P = .007) and lower EQ-5D-3L summary index scores (β, -0.061; 95% CI, -0.105 to -0.017; P = .007) but not with higher SSM physical function scores (β, 0.068; 95% CI, -0.036 to 0.172; P = .20). The type of index operation was not significantly associated with the corresponding outcomes.

CONCLUSIONS AND RELEVANCE

This cohort study showed no significant association between the type of index operation for DLSS-decompression alone or fusion-and the need for revision surgery or the outcomes of pain, disability, and quality of life among patients after 3 years. Number of revision operations was associated with more pain and worse quality of life.

Disability, Health-Related Quality of Life and Mortality in Lumbar Spine Fusion Patients-A 5-Year Follow-Up and Comparison With a Population Sample

STUDY DESIGN

Prospective follow-up study.

OBJECTIVES

We aimed to assess the effect of lumbar spine fusion (LSF) on disability, health-related quality of life and mortality in a 5-year follow-up, and to compare these results with the general population.

METHODS

523 consecutive LSF operations were included in a prospective follow-up. Disability was assessed by the Oswestry Disability Index (ODI), and HRQoL by the 36-item Short Form (SF-36) questionnaire using the physical and mental summary scores (PCS and MCS). The patients were compared with an age-, sex-, and residential area matched general population cohort.

RESULTS

The preoperative ODI in the patients was 46 (SD 16), and the change at 5 years was -26 (95% CI: -24 to -28), p < 0.001. In the population, ODI (baseline 13, SD 16) remained unchanged. The preoperative PCS in the patients was 27 (SD 7), in the population 45 (SD 11), and the increase in the patients at 5 years was 8 (95% CI: 7 to 9), p < 0.001. The patients did not reach the population in ODI or PCS. The baseline MCS in the patients was 47 (SD 13), and the change at 5 years 4 (95% CI: 3 to 7), p < 0.001. MCS of the females reached the population at 5-year follow-up. When analyzing short and long fusions separately, comparable changes were seen in both subgroups. There was no difference in mortality between the patients (3.4%) and the population (4.8%), hazard ratio (HR) 0.86.

CONCLUSIONS

Although the patients who had undergone LSF benefited from surgery still at 5 years, they never reached the physical level of the population.

Analysis of Patient-reported Outcomes Measures Used in Lumbar Fusion Surgery Research for Degenerative Spondylolisthesis

STUDY DESIGN

Meta-analyses.

OBJECTIVE

This study aims to document the most common Patient-reported Outcome Measures (PROMs) used to assess lumbar fusion surgery outcomes and provide an estimate of the average improvement following surgical treatment.

SUMMARY OF BACKGROUND DATA

As health care institutions place more emphasis on quality of care, accurately quantifying patient perceptions has become a valued tool in measuring outcomes. To this end, greater importance has been placed on the use of PROMs. This is a systemic review and meta-analysis of randomly controlled trials published between 2014 and 2019 assessing surgical treatment of degenerative spondylolisthesis.

METHODS

A fixed effect size model was used to calculate mean difference and a 95% confidence interval (95% CI). Linear regression was used to calculate average expected improvement, adjusted for preoperative scores.

RESULTS

A total of 4 articles (7 study groups) were found for a total of 444 patients. The 3 most common PROMs were Oswestry Disability Index (ODI) (n=7, 100%), Short-Form-12 or Short-Form-36 (SF-12/36) (n=4, 57.1%), and visual analog scale-back pain (n=3, 42.8%). Pooled average improvement was 24.12 (95% CI: 22.49-25.76) for ODI, 21.90 (95% CI: 19.71-24.08) for SF-12/36 mental component score, 22.74 (95% CI: 20.77-24.71) for SF-12/36 physical component score, and 30.87 (95% CI: 43.79-47.97) for visual analog scale-back pain. After adjusting for preoperative scores, patients with the mean preoperative ODI (40.47) would be expected to improve by 22.83 points postoperatively.

CONCLUSIONS

This study provides a range of expected improvement for common PROMs used to evaluate degenerative spondylolisthesis with the goal of equipping clinicians with a benchmark value to use when counseling patients regarding surgery. In doing so, it hopes to provide a comparison point by which to judge individual patient improvement.

LEVEL OF EVIDENCE

Level II.

Long-term Radiological and Clinical Outcome after Lumbar Spinal Fusion Surgery in Patients with Degenerative Spondylolisthesis: A Prospective 6-Year Follow-up Study

Objective

To assess which radiological alignment parameters are associated with a satisfactory long‐term clinical outcome after performing lumbar spinal fusion for treating degenerative spondylolisthesis.

Methods

This single‐center prospective study assessed the relation between radiological alignment parameters measured on standing lateral lumbar spine radiographs and the patient‐reported outcome using four different questionnaires (COMI, EQ‐5D, ODI and VAS) as primary outcome measures (level of evidence: II). The following spinopelvic alignment parameters were used: gliding angle, sacral inclination, anterior displacement, sagittal rotation, lumbar lordosis, sacral slope, pelvic tilt and pelvic incidence. Furthermore, the length of stay and perioperative complications were documented. Only cases from 2013 to 2015 of low‐grade degenerative lumbar spondylolisthesis (Meyerding grades I and II) were considered. The patients underwent open posterior lumbar fusion surgery by pedicle screw instrumentation and cage insertion. The operative technique was either a posterior lumbar interbody fusion (PLIF) or a transforaminal lumbar interbody fusion (TLIF) performed by three different senior orthopedic surgeons. Exclusion criteria were spine fractures, minimally invasive techniques, underlying malignant diseases or acute infections, previous or multisegmental spine surgery as well as preoperative neurologic impairment. Of 89 initially contacted patients, 17 patients were included for data analysis (11 males, six females).

Results

The data of 17 patients after mono‐ or bisegmental lumbar fusion surgery to treat low‐grade lumbar spondylolisthesis and with a follow‐up time of least 72 months were analyzed. The mean age was 66.7 ± 11.3 years. In terms of complications two dural tears and one intraoperative bleeding occurred. The average body mass index (BMI) was 27.6 ± 4.4 kg/m² and the average inpatient length of stay was 12.9 ± 3.8 days (range: 8–21). The long‐term clinical outcome correlated significantly with the change of the pelvic tilt (r_s = −0.515, P < 0.05) and the sagittal rotation (r_s = −0.545, P < 0.05). The sacral slope was significantly associated with the sacral inclination (r_s = 0.637, P < 0.01) and the pelvic incidence (r_s = 0.500, P < 0.05). In addition, the pelvic incidence showed a significant correlation with the pelvic tilt (r_s = 0.709, P < 0.01). The change of the different clinical scores over time also correlated significantly between the different questionnaires.

Conclusions

The surgical modification of the pelvic tilt and the sagittal rotation are the two radiological alignment parameters that can most accurately predict the long‐term clinical outcome after lumbar interbody fusion surgery.

Stability of SF-36 profiles between 2007 and 2016: A study of 27,302 patients surgically treated for lumbar spine diseases

Background

Previous studies have shown that patients with different lumbar spine diseases report different SF-36 profiles, but data on the stability of the SF-36 profiles are limited. The primary aim of the current study was to evaluate the stability of the SF-36 profile for lumbar spine diseases.

Methods

Patients, surgically treated between 2007 and 2016 for three lumbar spine diseases, lumbar spinal stenosis (LSS) with degenerative spondylolisthesis (DS), LSS without DS, and lumbar disk herniations (LDH), were identified in the Swedish spine register. Preoperative and 1 year postoperative SF-36 data for a total of 27,302 procedures were available for analysis. The stability of the SF-36 profiles over the 10-year period was evaluated using graphical exploration, linear regression, difference in means, and 95% confidence intervals. The responsiveness of the SF-36 domains to surgical treatment was evaluated using the standardized response mean (SRM).

Results

LSS and LDH have different SF-36 profiles. LSS with DS and LSS without DS have similar SF-36 profiles. The preoperative and the 1 year postoperative SF-36 profiles were stable from 2007 to 2016 for all three diagnoses. There were no major changes in the effect size of change (SRM) during the study period for all three diagnoses. For LSS with DS, the number of fusions peaked in 2010 and then decreased. The postoperative SF-36 profiles for LSS with DS were unaffected by changes in surgical treatment trends.

Conclusions

Patients with lumbar spinal stenosis and lumbar disk herniations have different SF-36 profiles. Concomitant degenerative spondylolisthesis had no impact on the SF-36 profile of lumbar spinal stenosis. Adding fusion to the decompression did not alter the postoperative SF-36 profile of lumbar spinal stenosis. The SF-36 health profiles are stable from a 10 years perspective.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12955-022-01999-7.

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

Background

There have been lingering controversies reported decompression and plus fusion. And the relative safety of fusion in addition to standard decompression remains unclear. This study aimed to assess the effectiveness and safety of decompression alone or combined with fusion in lumbar spinal stenosis (LSS) with degenerative spondylolisthesis (DS).

Methods

In this systematic review and meta-analysis, we searched the databases of PubMed, Embase, Cochrane Library, and Web of Science for relevant literature from their inception to 28th December 2021. We identified the eligible studies based on the PICOS principles, populations (LSS with DS), interventions (decompression alone), controls (decompression combined with fusion), outcomes [overall reoperation rate, complications, Oswestry Disability Index (ODI), operative time, the amount of blood lost, length of stay (LOS), and visual analog scales (VAS)], study design (cohort studies). Quality assessment for individual study was performed with the Newcastle-Ottawa Scale (NOS).

Results

In all, 12 articles involving a total of 14,693 patients were finally included in the study, the majority of patients underwent decompression alone (DA group: n=11,598) and the rest underwent decompression associated with fusion (FU group: n=3,095). The quality of most of the included studies was regarded as high quality. The results indicated that the FU group had a higher rate of complication [relative risk (RR): 1.770, 95% confidence interval (CI): 1.485 to 2.110], longer operative time [weighted mean difference (WMD): 51.037, 95% CI: 13.743 to 88.330], and increased blood loss (WMD: 258.354, 95% CI: 150.468 to 366.239) than the DA group (all P<0.05), with no significant differences for overall reoperation rate (RR: 0.879, 95% CI: 0.432 to 1.786), ODI (WMD: −2.569, 95% CI: −6.548 to 1.409), LOS (WMD: 3.838, 95% CI: −2.172 to 9.848), and VAS found between the two groups (P>0.05).

Conclusions

In patients with LSS + DS, the effectiveness and safety of decompression alone may be superior to decompression plus fusion in terms of complication rate, operative time, and the amount of bleeding. However, more high-quality literature is needed in the future to confirm the best treatment choice for patients with LSS + DS.

Responsiveness of the Zurich Claudication Questionnaire, the Oswestry Disability Index, the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, the 8-Item Short Form Health Survey, and the Euroqol 5 dimensions 5 level in the assessment of patients with lumbar spinal stenosis

PURPOSE

To assess the responsiveness of the Zurich Claudication Questionnaire (ZCQ), the Oswestry Disability Index, the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, the visual analog scale (VAS), the 8-Item Short Form Health Survey (SF-8), and the EuroQol 5 dimensions 5 level as methods of assessing outcomes of surgery for lumbar spinal stenosis.

METHODS

We analyzed 218 patients who had undergone lumbar surgery for spinal stenosis and completed one year of follow-up. The internal responsiveness of each questionnaire and any domains was assessed by the effect size and standardized response mean. External responsiveness was assessed by the Spearman rank correlation coefficient and the receiver operating characteristics (ROC) curve.

RESULTS

The most responsive assessments were "symptom severity" and "physical function" on the ZCQ, "walking ability" on the JOABPEQ, "leg pain" on the VAS, and "social function" on the JOABPEQ. The moderately responsive assessments were the physical component summary on the SF-8, the ODI, the EQ5D-5L, "low back pain" on the JOABPEQ, and "leg numbness" on the VAS. The least responsive assessments were "low back pain" on the VAS, "mental health" and "lumbar function" on the JOABPEQ, and the mental component summary on the SF-8.

CONCLUSIONS

Because of its high responsiveness, "symptom severity" on the ZCQ is recommended as a primary tool for assessing outcome when designing prospective studies for lumbar spinal stenosis.

Oblique Lateral Interbody Fusion vs. Minimally Invasive Transforaminal Lumbar Interbody Fusion for Lumbar Spinal Stenosis: A Retrospective Cohort Study

Background

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is an effective surgical option for lumbar spinal stenosis (LSS) with spondylolisthesis. However, few studies have discussed oblique lateral interbody fusion (OLIF) with MIS-TLIF.

Objective

To evaluate postoperative improvements, complications, and reoperation rates between patients with LSS undergoing OLIF or MIS-TLIF.

Methods

We retrospectively studied 113 LLS patients who underwent OLIF (53) or MIS-TLIF (60) with percutaneous pedicle screw fixation between January 2016 and December 2018. We measured estimated blood loss, operative time, hospital stay, reoperation, and complication incidence, visual analog scale (VAS), Oswestry Disability Index (ODI), Japanese Orthopedic Association (JOA), and Short Form-36 (SF-36) scores, discal and foraminal height and lumbar lordotic angle.

Results

The mean age was 58.81 ± 0.9 years. The TLIF group had increased operation time, blood loss, and hospital stays (p = 0.007, 0.001, and 0.016, respectively). Postoperatively, VAS and ODI scores significantly decreased while JOA and SF-36 scores significantly increased. The postoperative differences in main outcomes between the groups were insignificant (all p &gt; 0.05). The OLIF group had the lowest rates of overall (9.8% OLIF vs. 12.9% MIS-TLIF), intraoperative (3.9% OLIF vs. 4.8% MIS-TLIF), and postoperative complications (5.9% OLIF vs. 8.1% MIS-TLIF), but the differences were insignificant (p = 0.607, 0.813, and 0.653, respectively). The reoperation rate did not differ significantly (3.8% OLIF vs. 3.3% MIS-TLIF) (p = 0.842). OLIF restored disc height (74.4 vs. 32.0%), foraminal height (27.4 vs. 18.2%), and lumbar lordotic angle (3.5 vs. 1.1%) with greater success than did MIS-TLIF.

Conclusion

Patients undergoing OLIF with LSS improved similarly to MIS-TLIF patients. OLIF restored disc height, foraminal height and lumbar lordotic angle more successfully than did MIS-TLIF.

Clinical Evaluation of Surgery for Single-Segment Lumbar Spinal Stenosis: A Systematic Review and Bayesian Network Meta-Analysis

To compare the efficacy and safety of different surgical procedures for patients with single‐segment lumbar spinal stenosis (LSS), Bayesian network meta‐analysis (NMA) was conducted in this study. Randomized controlled trials (RCTs) which reported 2 years' results after surgery were searched from PubMed, Embase, and Cochrane Register of Controlled Trials up to February 2021. Eligible RCTs that contained at least two of the following surgical procedures, bilateral decompression via the unilateral approach (BDUL), decompression with conventional laminectomy (CL), decompression with fusion (DF), endoscopic decompression (ED), interspinous process devices only (IPDs), decompression with interlaminar stabilization (DILS), decompression with lumbar spinal process‐splitting laminectomy (LSPSL), and minimally invasive tubular decompression (MTD), would be included after screening based on the inclusion and exclusion criteria. The primary outcome was Oswestry Disability Index (ODI). Twenty eligible RCTs were included, with a total of 2201 patients enrolled. The NMA showed that the following surgical procedures ranked first (surface under the cumulative ranking) when compared with CL and DF: DILS for ODI (SUCRA 87.8%); LSPSL for back pain (95%); and MTD for leg pain (95.6%). MTD ranked among the top three surgical procedures for most outcomes. The quality of the synthesized evidence was low according to the Grading of Recommendations Assessment, Development, and Evaluation criteria. DILS, LSPSL, MTD, IPDs, and ED are the most effective procedures for patients with single‐segment LSS. Because of combining efficacy and safety, MTD may be the most promising routine surgical option for treating single‐segment LSS.

Clinical Evaluation of Paraspinal Mini-Tubular Lumbar Decompression and Minimally Invasive Transforaminal Lumbar Interbody Fusion for Lumbar Spondylolisthesis Grade I with Lumbar Spinal Stenosis: A Cohort Study

Objective

To investigate the clinical outcome data and difference in efficacy between paraspinal mini-tubular lumbar decompression (PMTD) and minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) in the treatment of degenerative lumbar spondylolisthesis grade I with lumbar spinal stenosis (DLS-I-LSS).

Methods

Patients with DLS-I-LSS, who underwent PMTD or MIS TLIF from September 2017 to March 2020, were included retrospectively. The follow-up period was 24 months after surgery. Outcome measurements included the Oswestry disability index (ODI) score, visual analog scale (VAS) low back pain score, VAS leg pain score, surgical data, and adverse events.

Results

A total of 104 patients with DLS-I-LSS were included in this study. The average improvement in ODI at 12 months (2.0%, 95% CI, −5.7% to 1.8%; p = 0.30) and 24 months (1.7%, 95% CI, −2.7% to 6.1%; p = 0.45) after surgery between the two groups were not statistically significant. The improvement in VAS low back pain score after 24 months and improvement in VAS leg pain score were not significantly different between the two groups. Compared with the PMTD group, the MIS TLIF group had more estimated blood loss and longer hospital stays. The cumulative reoperation rates were 5.66% and 1.96% in the MIS TLIF and PMTD groups, respectively (p = 0.68). The results of multivariate analysis showed that BMI, diabetes, and baseline ODI score were the main factors influencing the improvement in ODI in patients with DLS-I-LSS after minimally invasive surgery, accounting for 50.5% of the total variance.

Conclusions

The clinical effectiveness of PMTD was non-inferior to that of MIS TLIF for DLS-I-LSS; however, there was a reduced duration of hospital stay, operation time, blood loss, and hospitalization costs in the PMTD group. BMI, presence or absence of diabetes and baseline ODI score were influencing factors for the improvement of ODI (Trial Registration: ChiCTR2000040025).

Diagnosis and Management of Lumbar Spinal Stenosis: A Review

IMPORTANCE

Lumbar spinal stenosis is a prevalent and disabling cause of low back and leg pain in older persons, affecting an estimated 103 million persons worldwide. Most are treated nonoperatively. Approximately 600 000 surgical procedures are performed in the US each year for lumbar spinal stenosis.

OBSERVATIONS

The prevalence of the clinical syndrome of lumbar spinal stenosis in US adults is approximately 11% and increases with age. The diagnosis can generally be made based on a clinical history of back and lower extremity pain that is provoked by lumbar extension, relieved by lumbar flexion, and confirmed with cross-sectional imaging, such as computed tomography or magnetic resonance imaging (MRI). Nonoperative treatment includes activity modification such as reducing periods of standing or walking, oral medications to diminish pain such as nonsteroidal anti-inflammatory drugs (NSAIDs), and physical therapy. In a series of patients with lumbar spinal stenosis followed up for up to 3 years without operative intervention, approximately one-third of patients reported improvement, approximately 50% reported no change in symptoms, and approximately 10% to 20% of patients reported that their back pain, leg pain, and walking were worse. Long-term benefits of epidural steroid injections for lumbar spinal stenosis have not been demonstrated. Surgery appears effective in carefully selected patients with back, buttock, and lower extremity pain who do not improve with conservative management. For example, in a randomized trial of 94 participants with symptomatic and radiographic degenerative lumbar spinal stenosis, decompressive laminectomy improved symptoms more than nonoperative therapy (difference, 7.8 points; 95% CI, 0.8-14.9; minimum clinically important difference, 10-12.8) on the Oswestry Disability Index (score range, 0-100). Among persons with lumbar spinal stenosis and concomitant spondylolisthesis, lumbar fusion increased symptom resolution in 1 trial (difference, 5.7 points; 95% CI, 0.1 to 11.3) on the 36-Item Short Form Health Survey physical dimension score (range, 0-100), but 2 other trials showed either no important differences between the 2 therapies or noninferiority of lumbar decompression alone compared with lumbar decompression plus spinal fusion (MCID, 2-4.9 points). In a noninferiority trial, 71.4% treated with lumbar decompression alone vs 72.9% of those receiving decompression plus fusion achieved a 30% or more reduction in Oswestry Disability Index score, consistent with the prespecified noninferiority hypothesis. Fusion is associated with greater risk of complications such as blood loss, infection, longer hospital stays, and higher costs. Thus, the precise indications for concomitant lumbar fusion in persons with lumbar spinal stenosis and spondylolisthesis remain unclear.

CONCLUSIONS AND RELEVANCE

Lumbar spinal stenosis affects approximately 103 million people worldwide and 11% of older adults in the US. First-line therapy is activity modification, analgesia, and physical therapy. Long-term benefits from epidural steroid injections have not been established. Selected patients with continued pain and activity limitation may be candidates for decompressive surgery.

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.

Comparison of decompression, decompression plus fusion, and decompression plus stabilization: a long-term follow-up of a prospective, randomized study

BACKGROUND CONTEXT

Lumbar canal stenosis due to degenerative lumbar spondylolisthesis is one of the most common indications for lumbar spinal surgery. However, from a long-term perspective, it is still unclear which of these procedures should be performed: decompression, decompression plus fusion, or decompression plus stabilization.

PURPOSE

This study aimed to present the long-term results of a randomized controlled trial of surgery for degenerative spondylolisthesis.

STUDY DESIGN/SETTING

This is a long-term follow-up of a previously reported randomized controlled trial.

PATIENT SAMPLE

Patients aged ≤75 years with single L4/5 level lumbar canal stenosis caused by degenerative lumbar spondylolisthesis were enrolled at two hospitals from May 1, 2003, to April 30, 2012; the final follow-up was on May 20, 2021.

OUTCOME MEASURES

The following data were collected: modified Japanese Orthopedic Association (JOA) score, visual analog scale (VAS) score for lower back pain, leg pain, and numbness, and scores from eight Short-Form 36 (SF-36) subscales preoperatively, 1 year postoperatively, 5 years postoperatively, and at the final follow-up.

METHODS

Patients were randomized to undergo decompression alone, decompression plus fusion, or decompression plus stabilization. The primary outcome measure was the change in VAS for lower back pain with secondary outcomes including the modified JOA score, VAS for leg pain, VAS for leg numbness, eight SF-36 subscale scores, and occurrence of reoperation at the last follow-up.

RESULTS

Among 85 patients who were randomized, 66 responded to the current survey. The mean follow-up period was 12.3 years. The VAS score for low back pain improvement was not significantly different between the decompression and fusion groups at the mean follow-up of 12.3 years. Of the 12 secondary outcomes, 8 showed no significant difference between decompression and fusion, 12 showed no significant difference between decompression and stabilization, and 10 showed no significant difference between fusion and stabilization.

CONCLUSIONS

Although additional instrumentation surgery did not significantly improve low back pain at the mean follow-up of 12.3 years compared with decompression alone, fusion surgery provided clinically meaningful improvements in patient-reported vitality, social functioning, role limitations due to personal or emotional problems, and mental health compared with decompression alone.

TRIAL REGISTRATION

UMIN000028114.

Neurosurgical Study Design: Past and Future

Clinical trials are performed to determine the safety, efficacy, or effectiveness of a medical or surgical intervention. A clinical trial is, by definition, prospective in nature with a uniform treatment of a defined patient cohort. The outcomes assessment should also be uniform. Often a control group is included. At present, the number of neurosurgical clinical trials is increasing, and the study designs have become more sophisticated. Historically, the standard of neurosurgical care has evolved from the findings from many case series and retrospective comparative studies. However, in the present report, we have focused exclusively on prospective clinical trials. An urgent need exists to understand how clinical trials have been performed in the past and how they can be improved to advance our neurosurgical practice. In the present review, we have discussed the barriers, successes, and failures regarding prospective clinical trials in neurosurgery with an outlook to the future.

Laminectomy Versus Laminectomy with Fusion for Intradural Extramedullary Tumors: A Systematic Review and Meta-Analysis

OBJECTIVE

The primary objective of our systematic review and meta-analysis was to systematically compare the reported outcomes between laminectomy and laminectomy with fixation/fusion (LF) for the treatment of intradural extramedullary tumors (IDEMTs). Our secondary objective was to compare the outcomes between different laminectomy exposure techniques.

METHODS

PubMed and Embase were queried for literature on laminectomy and LF for IDEMTs. Reports of transforaminal approaches, interlaminar approaches, corpectomy, pediatrics patients, intramedullary tumors, technical studies, animal or cadaver studies, and literature reviews were excluded. The outcome measures recorded were pain, neurologic function, functional independence, cerebrospinal fluid leak, and wound infection. Where possible, the laminectomy technique (partial laminectomy [PL] vs. total laminectomy [TL]) was specified. Stata, version 17, was used for the fixed effects inverse variance meta-analysis.

RESULTS

Of 1849 reports assessed, 17 were included. The meta-analysis revealed that laminectomy (PL or TL) resulted in higher rates of postoperative sagittal instability compared with LF (odds ratio, 1.81; P < 0.001). No differences in any other postoperative outcome were observed between laminectomy and LF (P = 0.44). The systematic review also revealed no differences in postoperative pain, neurologic function, or functional independence or disability between PL and TL. Some evidence suggested that TL might result in greater rates of sagittal instability compared with PL.

CONCLUSIONS

No differences between LF, PL, or TL in pain, neurologic deficit, functional independence, cerebrospinal fluid leak, or wound infection were reported. Laminectomy had greater odds of sagittal instability compared with LF. Patients with preoperative sagittal instability requiring extensive removal of the posterior spinal column to achieve adequate resection of large tumors might benefit from LF.

Acute development of spinal lumbar synovial facet cyst within 1 week after lumbar decompression: illustrative case

BACKGROUND

Synovial facet cysts can sometimes develop in patients with lumbar spinal stenosis after decompressive laminectomy. The etiology of spinal lumbar synovial cysts is still unclear, but their formation is associated with underlying spinal instability, facet joint arthropathy, and degenerative spondylolisthesis.

OBSERVATIONS

A 61-year-old-male patient presented with neurogenic claudication due to lumbar spinal stenosis. Radiographic studies showed grade I spondylolisthesis and radiological predictors of delayed spinal instability. He underwent lumbar decompression and shortly thereafter developed spinal instability and recurrent symptoms, with formation of a new spinal lumbar synovial facet cyst. He required revisional decompression, cyst excision, and posterolateral spinal fusion for definitive treatment.

LESSONS

The literature reports postoperative spinal instability in up to one-third of patients with lumbar spinal stenosis and stable degenerative spondylolisthesis who undergo decompressive laminectomy. Close radiographic monitoring and early advanced imaging may be prudent in this patient population if they develop new postoperative neurological symptoms and show radiographic predictors of instability on preoperative imaging. Posterolateral spinal fusion with instrumentation should be considered in addition to lumbar decompression in this select group of patients who demonstrate radiographic predictors of delayed spinal instability if they are medically capable of tolerating a spinal fusion procedure.

Reoperations After Decompression With or Without Fusion for L3-4 Spinal Stenosis With Degenerative Spondylolisthesis: A Study of 372 Patients in Swespine, the National Swedish Spine Register

STUDY DESIGN

Register study with prospectively collected data.

OBJECTIVE

The aim was to investigate reoperation rates at the index level and the adjacent levels after surgery for lumbar L3-4 spinal stenosis with concomitant degenerative spondylolisthesis (DS).

SUMMARY OF BACKGROUND DATA

There are different opinions on how to surgically address lumbar spinal stenosis with DS. The potential benefit of fusion surgery should be weighed against the risks of future reoperations because of adjacent segment degeneration. Data on the reoperation rate at adjacent segments after single level L3-4 fusion surgery are limited.

MATERIALS AND METHODS

A total of 372 patients, who underwent surgery for lumbar L3-4 spinal stenosis with DS (slip >3 mm) between 2007 and 2012, were followed between 2007 and 2017 to identify reoperations at the index level and adjacent levels. The reoperation rate for decompression and fusion was compared with the reoperation rate for decompression only. Patient-reported outcome measures before and 1 year after surgery were evaluated.

RESULTS

The reoperation rate at the index level (L3-4) was 3.5% for decompression and fusion and 5.6% for decompression only. At the cranial adjacent level (L2-3), the corresponding numbers were 6.6% and 4.2%, respectively, and the caudal adjacent level (L4-5), the corresponding numbers were 3.1% and 4.9%, respectively. The effect sizes of change were larger for decompression and fusion compared with decompression only. The effect sizes of change were similar for leg pain and back pain.

CONCLUSIONS

We could not identify any differences in reoperation rates at the cranial or caudal adjacent segment after decompression and fusion compared with decompression only for L3-4 spinal stenosis with DS. The improvement in back pain is similar to the improvement in leg pain after surgery for L3-4 spinal stenosis with DS.

Postoperative Glycemic Variability as a Predictor of Adverse Outcomes Following Lumbar Fusion

STUDY DESIGN

A retrospective cross-sectional study.

OBJECTIVE

This study aims to evaluate the effect size of postoperative glycemic variability on surgical outcomes among patients who have undergone one- to three-level lumbar fusion.

SUMMARY OF BACKGROUND DATA

While numerous patient characteristics have been associated with surgical outcomes after lumbar fusion, recent studies have described the measuring of postoperative glycemic variability as another promising marker.

METHODS

A total of 850 patients were stratified into tertiles (low, moderate, high) based on degree of postoperative glycemic variability defined by coefficient of variation (CV). Surgical site infections were determined via chart review based on the Centers for Disease Control and Prevention definition. Demographic factors, surgical characteristics, inpatient complications, readmissions, and reoperations were determined by chart review and telephone encounters.

RESULTS

Overall, a statistically significant difference in 90-day adverse outcomes was observed when stratified by postoperative glycemic variability. In particular, patients with high CV had a higher odds ratio (OR) of readmission (OR = 2.19 [1.17, 4.09]; P = 0.01), experiencing a surgical site infection (OR = 3.22 [1.39, 7.45]; P = 0.01), and undergoing reoperations (OR = 2.65 [1.34, 5.23]; P = 0.01) compared with patients with low CV. No significant association was seen between low and moderate CV groups. Higher CV patients were more likely to experience longer hospital stays (β: 1.03; P = 0.01). Among the three groups, high CV group experienced the highest proportion of complications.

CONCLUSION

Our study establishes a significant relationship between postoperative glycemic variability and inpatient complications, length of stay, and 90-day adverse outcomes. While HbA1c has classically been used as the principal marker to assess blood glucose control, our results show CV to be a strong predictor of postoperative adverse outcomes. Future high-quality, prospective studies are necessary to explore the true effect of CV, as well as its practicality in clinical practice. Nevertheless, fluctuations in blood glucose levels during the inpatient stay should be limited to improve patient results.Level of Evidence: 4.

Utility of the decubitus or the supine rather than the extension lateral radiograph in evaluating lumbar segmental instability

OBJECTIVE

To determine the superiority of decubitus and supine radiographs for the reduction of olisthesis instead of the extension radiograph, and the inconsistency of the CT scout view, 3D-reconstruction and MR image in evaluating segmental instability.

METHODS

A cohort of 154 low-grade lumbar degenerative spondylolisthesis patients with the average age of (60.9 ± 8.6) years were enrolled. Slip percentage was measured on the flexion, upright and extension radiographs, the decubitus lateral radiograph, CT scout view, the supine median sagittal 3D-reconstruction and MR image. The translational range of motion was calculated, and segmental instability was defined as translational motion ≥ 8%.

RESULTS

The flexion radiograph showed higher slip percentage than upright radiograph (p < 0.001). The slip percentage of the MR image was lower than CT scout view (p = 0.003) and CT sagittal radiograph (p = 0.001) on the basis of statistical differences among three groups (p = 0.002). The slip percentage of the CT scout view, decubitus radiograph, and extension radiograph was statistically different (p = 0.01). The CT scout view and sagittal reconstruction had lower slip percentage than the extension radiograph (p = 0.042; p = 0.003, respectively). Both the flexion-supine and flexion-decubitus modality had larger translational motion than the flexion-extension modality (p = 0.007; p < 0.001, respectively).

CONCLUSION

Many modalities and techniques are used to show the vertebral displacement and its possible change and any cane used in the daily practice. In this study, supine and decubitus lateral radiography have larger reduction of olisthesis than the extension radiograph. The flexion radiograph coupled with a supine or decubitus radiograph reveals greater mobility than the flexion-extension modality.

The 100 Most Cited Articles on Lumbar Spinal Stenosis: A Bibliometric Analysis

STUDY DESIGN

Bibliometric analysis.

OBJECTIVE

With the increasing literature of spine surgery, some pioneering research studies have had a significant impact on the field of lumbar spinal stenosis (LSS). The objective of the authors was to identify and analyze the most frequently cited 100 articles in this field.

METHODS

Web of Science was searched to identify 100 top-cited articles related to LSS from 2000 to 2019. Articles on the final list were filtered based on their titles and abstracts. The following information were recorded and analyzed with bibliometric method: article title, first author, year of publication, journal of publication, total number of citations, country, institution, and study topic.

RESULTS

The citation count for final articles on the list ranged from 71 to 2162, with a mean number of 207.7. The journal Spine contributed the maximum number of articles (37), followed by European Spine Journal (9) and Pain Physician (8). There were collectively 80 first authors contributing to articles on the final list. Twelve authors were represented multiple times in the top 100 articles. The most prolific years were 2008 and 2009, each had 11 articles published. With regard to country and region of origin, most articles were from the United States (58). The most cited article was published in Spine in 2000 by Fairbank and Pynsent, who discussed the role of the Oswestry Disability Index as an evaluation standard in spinal disorders, including LSS.

CONCLUSION

The current study analyzed the 100 most cited articles on LSS. It no doubt developed a useful resource with detailed information for many, particularly orthopedic and neurosurgery physicians who want to assimilate research focus and advance of LSS within a relatively short period. Researchers may benefit from emphasis on citation count while citing and evaluating articles and realize the deficiencies when high-level articles appear.

How Decompression Surgery Improves the Lower Back Pain in Patient with Lumbar Degenerative Stenosis: A Propensity-score-matched Analysis

STUDY DESIGN

Multicenter retrospective case series of patients treated surgically for lumbar spinal stenosis (LSS).

OBJECTIVE

We investigated how laminectomy improves lower back pain (LBP) and the factors associated with poor improvement.

SUMMARY OF BACKGROUND DATA

Lumbar laminectomy is effective for alleviating neurological symptoms caused by LSS, whereas its effect on LBP is still controversial.

METHODS

A retrospective review of prospectively collected data from 436 patients (age 72 yrs, 69% males) who underwent laminectomy for LSS with 2 years of follow-up. We analyzed the following risk factors for residual LBP by uni- and multivariate analyses: age, sex, smoking, occupation, comorbidities, frailty, joint replacement, vertebral fracture, DISH, HRQOL, complications, and the presence of spinal instability. The LBP of male and female patients was analyzed after propensity score matching of known confounders. Patient-reported outcomes (JOABPEQ and VAS scores) were obtained at baseline and the 2-year postoperative follow-up.

RESULTS

LBP was significantly improved at 2 years post operation (VAS change 2.3 [95% CI 2.0-2.6], P < 0.01). Fifty-five percent of the patients achieved an MCID, with 67% having no or mild LBP. In the multivariate analysis, sex and baseline LBP were independent risk factors (female: OR 1.9 [1.2-3.0], baseline LBP [VAS≥7.5]: OR 1.9 [1.2-3.1]). Furthermore, the independent risk factors for severe baseline LBP were sex and mental status (female: OR 1.7 [1.1-2.7], P = 0.03, mental status: OR 3.8 [2.4-6.0], P < 0.01). However, an analysis of 102 pairs of propensity-score-matched male and female patients showed no difference in the improvement of LBP (male vs. female: VAS 3.8 ± 2.8 vs. 4.0 ± 2.9, P = 0.61, VAS change 3.1 ± 2.9 vs. 2.7 ± 3.0, P = 0.38).

CONCLUSION

Decompression surgery for LSS significantly improved LBP. Sex and baseline LBP were risk factors for residual LBP. However, when males and females were matched by confounders, no difference was found in the LBP after surgery. Patients with severe baseline LBP may need further evaluation for their mental status because these patients are likely to have mental problems that potentially contribute to persistent LBP.Level of Evidence: 4.

A Prospective Study of Lumbar Facet Arthroplasty in the Treatment of Degenerative Spondylolisthesis and Stenosis: Early Cost-effective Assessment from the Total Posterior Spine System (TOPS™) IDE Study

Background: Given the increased attention to functional improvement in spine surgery as it relates to motion preservation, activities of daily living, and cost, it is critical to fully understand the healthcare economic impact of new devices being tested in large FDA randomized controlled trials (RCT). The purpose of this analysis was to comprehensively evaluate the cost-effectiveness of the novel Total Posterior Spine (TOPS™) System investigational device compared with the trial control group, standard transforaminal lumbar interbody fusion (TLIF). Objective: To evaluate the cost-effectiveness of TOPS™ compared with TLIF. Methods: The study patient population was extracted from a multicenter RCT with current enrollment at n=121 with complete 1-year follow-up. The primary outcome was cost-effectiveness, expressed as the incremental cost-effectiveness ratio. Secondary outcomes were health-related utility, presented as quality-adjusted life-years (QALYs), and cost, calculated in US dollars. Analysis was conducted following Second Panel on Cost-Effectiveness Health and Medicine recommendations. The base case analysis utilized SF-36 survey data from the RCT. Both cost and QALY outcomes were discounted at a yearly rate of 3% to reflect their present value. A cohort Markov model was constructed to analyze perioperative and postoperative costs and QALYs for both TOPS™ and control groups. Scenario, probabilistic, and threshold sensitivity analyses were conducted to determine model discrimination and calibration. Results: The primary time horizon used to estimate cost and health utility was 2 years after index surgery. From a health system perspective, assuming a 50/50 split between Medicare and private payers, the TOPS™ cohort is cost-effective 2 years postoperatively ($6158/QALY) compared with control. At 6 years and beyond, TOPS™ becomes dominant, irrespective of payer mix and surgical setting. At willingness-to-pay thresholds of $100 000/QALY, 63% of all 5000 input parameter simulations favor TOPS, even with a $4000 upcharge vs TLIF. Discussion: The novel TOPS™ device is cost-effective compared with TLIF and becomes the dominant economic strategy over time. Conclusions: In the emerging, rapidly expanding field of value-based medicine, there will be an increased demand for these analyses, ensuring surgeons are empowered to make the best, most sustainable solutions for their patients and society.

Comparison of Lumbar Fusion With and Without Interbody Fusion for Lumbar Stenosis Using Patient-Reported Outcomes Measurement Information System (PROMIS) Computer Adaptive Testing (CAT)

Study design

This was a retrospective analysis of patient-reported outcomes across a two-year period.

Summary of background data

Patients suffering from lumbar stenosis may experience low back pain, neurogenic claudication, and weakness. Patients can benefit from surgical intervention, including decompression with or without fusion. However, the superiority of any single fusion construct remains controversial.

Objective

The goal of this study was to compare Patient-Reported Outcomes Measurement Information System (PROMIS®) Computer Adaptive Testing (CAT) measures in patients with lumbar spinal stenosis treated surgically with lumbar decompression and fusion with or without interbody fusion.

Methods

A retrospective review of patients with lumbar stenosis undergoing lumbar decompression and one-level fusion was performed. PROMIS® CAT Physical Function (PF) and Pain Interference (PI) assessments were administered using a web-based platform pre and postoperatively.

Results

Sixty patients with lumbar stenosis undergoing one-level lumbar fusion were identified. Twenty-seven patients underwent posterior lumbar fusion (PSF) alone and 33 underwent one-level lumbar interbody fusion (IF). Patients undergoing IF had better absolute PF scores compared to patients undergoing PSF at one-year postoperatively (48.9 v 41.6, p=0.002) and greater relative improvement in PF scores from baseline at one-year postoperatively (D13.6 v D8.6, p=0.02). A subgroup analysis of patients undergoing TLIF v PSF showed better absolute PF scores at the one-year follow-up in the TLIF group (47.1 v 42.3, p=0.04). No differences were found in PI scores at any time point between the PSF and IF groups. Patients undergoing IF had significantly shorter hospital stays (2.5 v 3.3 days, p=0.02) compared to patients undergoing PSF.

Conclusions

Patients with lumbar spinal stenosis treated with one-level IF reported higher absolute PF scores and experienced greater relative improvement in PF scores from baseline at one-year follow-up compared to patients treated with PSF alone. Additionally, IF is associated with a decreased length of hospital stay as compared to PSF.

Methodological aspects of a randomized within-patient concurrent controlled design for clinical trials in spine surgery

INTRODUCTION

Randomized controlled trials are considered the highest level of evidence, but their feasibility in the surgical field is severely hampered by methodological and practical issues. Concurrent comparison between the experimental and control conditions within the same patient can be an effective strategy to mitigate some of these challenges and improve generalizability, mainly by the elimination of between-patient variability and reduction of the required sample size. This article aims (1) to describe the methodological aspects of a randomized within-patient controlled trial and (2) to quantify the added value of this design, based on a recently completed randomized within-patient controlled trial on bone grafts in instrumented lumbar posterolateral spinal fusion.

METHODS

Boundary conditions for the application of the randomized within-patient controlled trial design were identified. Between-patient variability was quantified by the intraclass correlation coefficient and concordance in the primary fusion outcome. Sample size, study duration and costs were compared with a classic randomized controlled trial design.

RESULTS

Boundary conditions include the concurrent application of the experimental and control conditions to identical but physically separated sites. Moreover, the outcome of interest should be local, uncorrelated and independently assessable. The spinal fusion outcomes within a patient were found to be more similar than between different patients (intraclass correlation coefficient 32% and concordance 64%), demonstrating a clear effect of patient-related factors. The randomized within-patient controlled trial design allowed a reduction of the sample size to one-third of a parallel-group randomized controlled trial, thereby halving the trial duration and costs.

CONCLUSION

When suitable, the randomized within-patient controlled trial is an efficient design that provides a solution to some of the considerable challenges of a classic randomized controlled trial in (spine) surgery. This design holds specific promise for efficacy studies of non-active bone grafts in instrumented posterolateral fusion surgery.