Assessing the differences in operative and patient-reported outcomes between lateral approaches for lumbar fusion: a systematic review and indirect meta-analysis

OBJECTIVE

Anterior-to-psoas lumbar interbody fusion (ATP-LIF), more commonly referred to as oblique lateral interbody fusion, and lateral transpsoas lumbar interbody fusion (LTP-LIF), also known as extreme lateral interbody fusion, are the two commonly used lateral approaches for performing a lumbar fusion procedure. These approaches help overcome some of the technical challenges associated with traditional approaches for lumbar fusion. In this systematic review and indirect meta-analysis, the authors compared operative and patient-reported outcomes between these two select approaches using available studies.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach, the authors conducted an electronic search using the PubMed, EMBASE, and Scopus databases for studies published before May 1, 2019. Indirect meta-analysis was conducted on fusion rate, cage movement (subsidence plus migration), permanent deficits, and transient deficits; results were depicted as forest plots of proportions (effect size [ES]).

RESULTS

A total of 63 studies were included in this review after applying the exclusion criteria, of which 26 studies investigated the outcomes of ATP-LIF, while 37 studied the outcomes of LTP-LIF. The average fusion rate was found to be similar between the two groups (ES 0.97, 95% CI 0.84-1.00 vs ES 0.94, 95% CI 0.91-0.97; p = 0.561). The mean incidence of cage movement was significantly higher in the ATP-LIF group compared with the LTP-LIF group (stand-alone: ES 0.15, 95% CI 0.06-0.27 vs ES 0.09, 95% CI 0.04-0.16 [p = 0.317]; combined: ES 0.18, 95% CI 0.07-0.32 vs ES 0.02, 95% CI 0.00-0.05 [p = 0.002]). The mean incidence of reoperations was significantly higher in patients undergoing ATP-LIF than in those undergoing LTP-LIF (ES 0.02, 95% CI 0.01-0.03 vs ES 0.04, 95% CI 0.02-0.07; p = 0.012). The mean incidence of permanent deficits was similar between the two groups (stand-alone: ES 0.03, 95% CI 0.01-0.06 vs ES 0.05, 95% CI 0.01-0.12 [p = 0.204]; combined: ES 0.03, 95% CI 0.01-0.06 vs ES 0.03, 95% CI 0.00-0.08 [p = 0.595]). The postoperative changes in visual analog scale (VAS) and Oswestry Disability Index (ODI) scores were both found to be higher for ATP-LIF relative to LTP-LIF (VAS: weighted average 4.11 [SD 2.03] vs weighted average 3.75 [SD 1.94] [p = 0.004]; ODI: weighted average 28.3 [SD 5.33] vs weighted average 24.3 [SD 4.94] [p < 0.001]).

CONCLUSIONS

These analyses indicate that while both approaches are associated with similar fusion rates, ATP-LIF may be related to higher odds of cage movement and reoperations as compared with LTP-LIF. Furthermore, there is no difference in rates of permanent deficits between the two procedures.

Factors associated with progression and mortality among patients undergoing stereotactic radiosurgery for intracranial metastasis: results from a national real-world registry

OBJECTIVE

Stereotactic radiosurgery (SRS) has been increasingly employed in recent years to treat intracranial metastatic lesions. However, there is still a need for optimization of treatment paradigms to provide better local control and prevent progressive intracranial disease. In the current study, the authors utilized a national collaborative registry to investigate the outcomes of patients with intracranial metastatic disease who underwent SRS and to determine factors associated with lesion treatment response, overall progression, and mortality.

METHODS

The NeuroPoint Alliance SRS registry was queried for all patients with intracranial metastatic lesions undergoing single- or multifraction SRS at participating institutions between 2016 and 2020. The main outcomes of interest included lesion response (lesion-level analysis), progression using Response Assessment for Neuro-Oncology criteria, and mortality (patient-level analysis). Kaplan-Meier analysis was used to report time to progression and overall survival, and multivariable Cox proportional hazards analysis was used to investigate factors associated with lesion response, progression, and mortality.

RESULTS

A total of 501 patients (1447 intracranial metastatic lesions) who underwent SRS and had available follow-up were included in the current analyses. The most common primary tumor was lung cancer (49.5%, n = 248), followed by breast (15.4%, n = 77) and melanoma (12.2%, n = 61). Most patients had a single lesion (44.9%, n = 225), 29.3% (n = 147) had 2 or 3 lesions, and 25.7% (n = 129) had > 3 lesions. The mean sum of baseline measurements of the lesions according to Response Evaluation Criteria in Solid Tumors (RECIST) was 35.54 mm (SD 25.94). At follow-up, 671 lesions (46.4%) had a complete response, 631 (43.6%) had a partial response (≥ 30% decrease in longest diameter) or were stable (< 30% decrease but < 20% increase), and 145 (10%) showed progression (> 20% increase in longest diameter). On multivariable Cox proportional hazards analysis, melanoma-associated lesions (HR 0.48, 95% CI 0.34-0.67; p < 0.001) and larger lesion size (HR 0.94, 95% CI 0.93-0.96; p < 0.001) showed lower odds of lesion regression, while a higher biologically effective dose was associated with higher odds (HR 1.001, 95% CI 1.0001-1.00023; p < 0.001). A total of 237 patients (47.3%) had overall progression (local failure or intracranial progressive disease), with a median time to progression of 10.03 months after the index SRS. Factors found to be associated with increased hazards of progression included male sex (HR 1.48, 95% CI 1.108-1.99; p = 0.008), while administration of immunotherapy (before or after SRS) was found to be associated with lower hazards of overall progression (HR 0.62, 95% CI 0.460-0.85; p = 0.003). A total of 121 patients (23.95%) died during the follow-up period, with a median survival of 19.4 months from the time of initial SRS. A higher recursive partitioning analysis score (HR 21.3485, 95% CI 1.53202-3.6285; p < 0.001) was found to be associated with higher hazards of mortality, while single-fraction treatment compared with hypofractionated treatment (HR 0.082, 95% CI 0.011-0.61; p = 0.015), administration of immunotherapy (HR 0.385, 95% CI 0.233-0.64; p < 0.001), and presence of single compared with > 3 lesions (HR 0.427, 95% CI 0.187-0.98; p = 0.044) were found to be associated with lower risk of mortality.

CONCLUSIONS

The comparability of results between this study and those of previously published clinical trials affirms the value of multicenter databases with real-world data collected without predetermined research purpose.

Differences in postoperative quality of life in young, early elderly, and late elderly patients undergoing surgical treatment for degenerative cervical myelopathy

OBJECTIVE

Cervical spondylotic myelopathy (CSM) is a common progressive spine disorder affecting predominantly middle-aged and elderly populations. With increasing life expectancy, the incidence of CSM is expected to rise further. The outcomes of elderly patients undergoing CSM surgery and especially their quality of life (QOL) postoperatively remain undetermined. This study retrospectively reviewed patients to identify baseline differences and validated postoperative patient-reported outcome (PRO) measures in elderly patients undergoing CSM surgery.

METHODS

The multi-institutional, neurosurgery-specific NeuroPoint Quality Outcomes Database was queried to identify CSM patients treated surgically at the 14 highest-volume sites from January 2016 to December 2018. Patients were divided into three groups: young (< 65 years), early elderly (65-74 years), and late elderly (≥ 75 years). Demographic and PRO measures (Neck Disability Index [NDI] score, modified Japanese Orthopaedic Association [mJOA] score, EQ-5D score, EQ-5D visual analog scale [VAS] score, arm pain VAS, and neck pain VAS) were compared among the groups at baseline and 3 and 12 months postoperatively.

RESULTS

A total of 1151 patients were identified: 691 patients (60%) in the young, 331 patients (28.7%) in the early elderly, and 129 patients (11.2%) in the late elderly groups. At baseline, younger patients presented with worse NDI scores (p < 0.001) and lower EQ-5D VAS (p = 0.004) and EQ-5D (p < 0.001) scores compared with early and late elderly patients. No differences among age groups were found in the mJOA score. An improvement of all QOL scores was noted in all age groups. On unadjusted analysis at 3 months, younger patients had greater improvement in arm pain VAS, NDI, and EQ-5D VAS compared with early and late elderly patients. At 12 months, the same changes were seen, but on adjusted analysis, there were no differences in PROs between the age groups.

CONCLUSIONS

The authors' results indicate that elderly patients undergoing CSM surgery achieved QOL outcomes that were equivalent to those of younger patients at the 12-month follow-up.

Social risk factors predicting outcomes of cervical myelopathy surgery

OBJECTIVE

Combinations of certain social risk factors of race, sex, education, socioeconomic status (SES), insurance, education, employment, and one's housing situation have been associated with poorer pain and disability outcomes after lumbar spine surgery. To date, an exploration of such factors in patients with cervical spine surgery has not been conducted. The objective of the current work was to 1) define the social risk phenotypes of individuals who have undergone cervical spine surgery for myelopathy and 2) analyze their predictive capacity toward disability, pain, quality of life, and patient satisfaction-based outcomes.

METHODS

The Cervical Myelopathy Quality Outcomes Database was queried for the period from January 2016 to December 2018. Race/ethnicity, educational attainment, SES, insurance payer, and employment status were modeled into unique social phenotypes using latent class analyses. Proportions of social groups were analyzed for demonstrating a minimal clinically important difference (MCID) of 30% from baseline for disability, neck and arm pain, quality of life, and patient satisfaction at the 3-month and 1-year follow-ups.

RESULTS

A total of 730 individuals who had undergone cervical myelopathy surgery were included in the final cohort. Latent class analysis identified 2 subgroups: 1) high risk (non-White race and ethnicity, lower educational attainment, not working, poor insurance, and predominantly lower SES), n = 268, 36.7% (class 1); and 2) low risk (White, employed with good insurance, and higher education and SES), n = 462, 63.3% (class 2). For both 3-month and 1-year outcomes, the high-risk group (class 1) had decreased odds (all p < 0.05) of attaining an MCID score in disability, neck/arm pain, and health-related quality of life. Being in the low-risk group (class 2) resulted in an increased odds of attaining an MCID score in disability, neck/arm pain, and health-related quality of life. Neither group had increased or decreased odds of being satisfied with surgery.

CONCLUSIONS

Although 2 groups underwent similar surgical approaches, the social phenotype involving non-White race/ethnicity, poor insurance, lower SES, and poor employment did not meet MCIDs for a variety of outcome measures. This finding should prompt surgeons to proactively incorporate socially conscience care pathways within healthcare systems, as well as to optimize community-based resources to improve outcomes and personalize care for populations at social risk.

Does Direct Surgical Repair Benefit Pars Interarticularis Fracture? A Systematic Review and Meta-analysis

BACKGROUND

Promising results have been shown in previous studies from direct pars interarticularis repair. These include Scott wiring, Buck repair, pedicle screw repair, and Morscher techniques. In addition, several minimally invasive techniques have been reported to show high union rates, low rates of implant failure and wound complications, shorter length of stay, a lower postoperative pain score with faster recovery, and minimal blood loss.

OBJECTIVES

To compare the evidence on techniques for direct pars interarticularis repair.

STUDY DESIGN

Systematic review and meta-analysis.

SETTING

Review article.

METHODS

We conducted a comprehensive search of databases to identify studies assessing outcomes of direct pars interarticularis defect repair. Two authors independently screened electronic search results, performed study selection, and extracted data for meta-analysis. Sensitivity and subgroup analyses were performed to assess risk of bias.

RESULTS

Forty studies were included in the final analysis. Union rate was higher in the pedicle screw repair group (effect size [ES] 95%; 95% CI, 86% to 100%), followed by the Buck repair group (ES 93%; 95% CI, 86% to 98%), Scott wiring (ES 85%; 95% CI, 63% to 99%), and Morscher method group (ES 63%; 95% CI, 2% to 100%). Positive functional outcome was higher for the Morscher method (ES 91%; 95% CI, 86% to 96%), followed by the Buck repair group (ES 85%; 95% CI, 68% to 97%), pedicle screw repair (ES 84%; 95% CI, 59% to 99%) and Scott repair group (ES 80%; 95% CI, 60% to 95%). Complication rates were highest among the Scott repair group (ES 12%; 95% CI, 4% to 22%) and Morscher method group (ES 12%; 95% CI, 0% to 34%).

LIMITATIONS

Heterogeneity of the included studies were noted. However, we performed sensitivity analyses from the available data to address this issue.

CONCLUSION

Our results indicate that pedicle screw repair and Buck repair may be associated with a higher union rate and lower complication rates compared to the Scott repair and Morscher method. Ultimately, the choice of technique should be based on the surgeon's preference and experience.

Minimally invasive versus open lumbar spinal fusion: a matched study investigating patient-reported and surgical outcomes

OBJECTIVE

With the expanding indications for and increasing popularity of minimally invasive surgery (MIS) for lumbar spinal fusion, large-scale outcomes analysis to compare MIS approaches with open procedures is warranted.

METHODS

The authors queried the Quality Outcomes Database for patients who underwent elective lumbar fusion for degenerative spine disease. They performed optimal matching, at a 1:2 ratio between patients who underwent MIS and those who underwent open lumbar fusion, to create two highly homogeneous groups in terms of 33 baseline variables (including demographic characteristics, comorbidities, symptoms, patient-reported scores, indications, and operative details). The outcomes of interest were overall satisfaction, decrease in Oswestry Disability Index (ODI), and back and leg pain, as well as hospital length of stay (LOS), operative time, reoperations, and incidental durotomy rate. Satisfaction was defined as a score of 1 or 2 on the North American Spine Society scale. Minimal clinically important difference (MCID) in ODI was defined as ≥ 30% decrease from baseline. Outcomes were assessed at the 3- and 12-month follow-up evaluations.

RESULTS

After the groups were matched, the MIS and open groups consisted of 1483 and 2966 patients, respectively. Patients who underwent MIS fusion had higher odds of satisfaction at 3 months (OR 1.4, p = 0.004); no difference was demonstrated at 12 months (OR 1.04, p = 0.67). Lumbar stenosis, single-level fusion, higher American Society of Anesthesiologists Physical Status Classification System grade, and absence of spondylolisthesis were most prominently associated with higher odds of satisfaction with MIS compared with open surgery. Patients in the MIS group had slightly lower ODI scores at 3 months (mean difference 1.61, p = 0.006; MCID OR 1.14, p = 0.0495) and 12 months (mean difference 2.35, p < 0.001; MCID OR 1.29, p < 0.001). MIS was also associated with a greater decrease in leg and back pain at both follow-up time points. The two groups did not differ in operative time and incidental durotomy rate; however, LOS was shorter for the MIS group. Revision surgery at 12 months was less likely for patients who underwent MIS (4.1% vs 5.6%, p = 0.032).

CONCLUSIONS

In patients who underwent lumbar fusion for degenerative spinal disease, MIS was associated with higher odds of satisfaction at 3 months postoperatively. No difference was demonstrated at the 12-month follow-up. MIS maintained a small, yet consistent, superiority in decreasing ODI and back and leg pain, and MIS was associated with a lower reoperation rate.

Differences in Patient-Reported Outcomes Between Anterior and Posterior Approaches for Treatment of Cervical Spondylotic Myelopathy: A Quality Outcomes Database Analysis

OBJECTIVE

Surgery for cervical spondylotic myelopathy (CSM) may use anterior or posterior approaches. Our objective was to compare baseline differences and validated postoperative patient-reported outcome measures between anterior and posterior approaches.

METHODS

The NeuroPoint Quality Outcomes Database was queried retrospectively to identify patients with symptomatic CSM treated at 14 high-volume sites. Demographic, comorbidity, socioeconomic, and outcome measures were compared between treatment groups at baseline and 3 and 12 months postoperatively.

RESULTS

Of the 1151 patients with CSM in the cervical registry, 791 (68.7%) underwent anterior surgery and 360 (31.3%) underwent posterior surgery. Significant baseline differences were observed in age, comorbidities, myelopathy severity, unemployment, and length of hospital stay. After adjusting for these differences, anterior surgery patients had significantly lower Neck Disability Index score (NDI) and a higher proportion reaching a minimal clinically important difference (MCID) in NDI (P = 0.005 at 3 months; P = 0.003 at 12 months). Although modified Japanese Orthopaedic Association scores were lower in anterior surgery patients at 3 and 12 months (P < 0.001 and P = 0.022, respectively), no differences were seen in MCID or change from baseline. Greater EuroQol-5D improvement at 3 months after anterior versus posterior surgery (P = 0.024) was not sustained at 12 months and was insignificant on multivariate analysis.

CONCLUSIONS

In the largest analysis to date of CSM surgery data, significant baseline differences existed for patients undergoing anterior versus posterior surgery for CSM. After adjusting for these differences, patients undergoing anterior surgery were more likely to achieve clinically significant improvement in NDI at short- and long-term follow-up.

Factors associated with early shunt revision within 30 days: analyses from the National Surgical Quality Improvement Program

OBJECTIVE

CSF shunt insertion is the most commonly performed neurosurgical procedure for pediatric patients with hydrocephalus, and complications including infections and catheter obstruction are common. The rate of readmission in the first 30 days after surgery has been used across surgical disciplines to determine healthcare quality. In the current study, the authors sought to assess factors associated with early shunt revision within 30 days using real-world data.

METHODS

Targeted shunt data set participant user files of the National Surgical Quality Improvement Program (NSQIP) from 2016 to 2019 were queried for patients undergoing a shunt procedure. A multivariable logistic regression model was performed to assess the impact of demographics, etiologies, comorbidities, congenital malformations, and shunt adjuncts on shunt revision within 30 days, as well as shunt revision due to infection within 30 days.

RESULTS

A total of 3919 primary pediatric shunt insertions were identified in the NSQIP database, with a mean (± SD) patient age of 26.3 ± 51.6 months. There were a total of 285 (7.3%) unplanned shunt revisions within 30 days, with a mean duration of 14.9 ± 8.5 days to first intervention. The most common reason for intervention was mechanical shunt failure (32.6% of revision, 2.4% overall, n = 93), followed by infection (31.2% of all interventions, 2.3% overall, n = 89) and wound disruption or CSF leak (22.1% of all interventions, 1.6% overall, n = 63). Patients younger than 6 months of age had the highest overall unplanned 30-day revision rate (8.5%, 203/2402) as well as the highest 30-day shunt infection rate (3%, 72/2402). Patients who required a revision were also more likely to have a cardiac risk factor (34.7%, n = 99, vs 29.2%, n = 1061; p = 0.048). Multivariable logistic regression revealed that compared to patients 9-18 years old, those aged 2-9 years had significantly lower odds of repeat shunt intervention (p = 0.047), while certain etiologies including congenital hydrocephalus (p = 0.0127), intraventricular hemorrhage (IVH) of prematurity (p = 0.0173), neoplasm (p = 0.0005), infection (p = 0.0004), and syndromic etiology (p = 0.0136), as well as presence of ostomy (p = 0.0095), were associated with higher odds of repeat intervention. For shunt infection, IVH of prematurity was found to be associated with significantly higher odds (p = 0.0427) of shunt infection within 30 days, while use of intraventricular antibiotics was associated with significantly lower odds (p = 0.0085).

CONCLUSIONS

In this study of outcomes after pediatric shunt placement using a nationally derived cohort, early shunt failure and infection within 30 days were found to remain as considerable risks. The analysis of this national surgical quality registry confirms that, in accordance with other multicenter studies, hydrocephalus etiology, age, and presence of ostomy are important predictors of the need for early shunt revision. IVH of prematurity is associated with early infections while intraventricular antibiotics may be protective. These findings could be used for benchmarking in hospital efforts to improve quality of care for pediatric patients with hydrocephalus.

Disparities in Reported Testing for 1p/19q Codeletion in Oligodendroglioma and Oligoastrocytoma Patients: An Analysis of the National Cancer Database

Purpose

A chromosomal 1p/19q codeletion was included as a required diagnostic component of oligodendrogliomas in the 2016 World Health Organization (WHO) classification of central nervous system tumors. We sought to evaluate disparities in reported testing for 1p/19q codeletion among oligodendroglioma and oligoastrocytoma patients before and after the guidelines.

Methods

The National Cancer Database (NCDB) was queried for patients with histologically-confirmed WHO grade II/III oligodendroglioma or oligoastrocytoma from 2011-2017. Adjusted odds of having a reported 1p/19q codeletion test for patient- and hospital-level factors were calculated before (2011-2015) and after (2017) the guidelines. The adjusted likelihood of receiving adjuvant treatment (chemotherapy and/or radiotherapy) based on reported testing was also evaluated.

Results

Overall, 6,404 patients were identified. The reported 1p/19q codeletion testing rate increased from 45.8% in 2011 to 59.8% in 2017. From 2011-2015, lack of insurance (OR 0.77; 95% CI 0.62-0.97;p=0.025), lower zip code-level educational attainment (OR 0.62; 95% CI 0.49-0.78;p<0.001), and Northeast (OR 0.68; 95% CI 0.57-0.82;p<0.001) or Southern (OR 0.62; 95% CI 0.49-0.79;p<0.001) facility geographic region were negatively associated with reported testing. In 2017, Black race (OR 0.49; 95% CI 0.26-0.91;p=0.024) and Northeast (OR 0.50; 95% CI 0.30-0.84;p=0.009) or Southern (OR 0.42; 95% CI 0.22-0.78;p=0.007) region were negatively associated with reported testing. Patients with a reported test were more likely to receive adjuvant treatment (OR 1.73; 95% CI 1.46-2.04;p<0.001).

Conclusion

Despite the 2016 WHO guidelines, disparities in reported 1p/19q codeletion testing by geographic region persisted while new disparities in race/ethnicity were identified, which may influence oligodendroglioma and oligoastrocytoma patient management.

Disparities in the Use of Mechanical Thrombectomy Alone Compared with Adjunctive Intravenous Thrombolysis in Acute Ischemic Stroke in the United States

BACKGROUND AND PURPOSE

For patients with large-vessel occlusion, mechanical thrombectomy (MT) without IV-tPA is a proved strategy. The relative benefit of direct MT versus MT+IV-tPA for patients with indications for IV-tPA is being actively investigated. We used a national inpatient database to assess trends in use and patient profiles after MT+IV-tPA versus mechanical thrombectomy alone.

MATERIALS AND METHODS

The National Inpatient Sample was queried between 2013 and 2018 for patients undergoing mechanical thrombectomy for acute ischemic stroke. Patients who received mechanical thrombectomy alone were compared with those who underwent MT+IV-tPA. The Cochran-Armitage test was conducted to assess the linear trend of use of mechanical thrombectomy alone among the entire cohort and between admissions involving non-White and White patients. All estimates were nationalized using discharge weights.

RESULTS

A total of 89,645 weighted admissions were identified pertaining to mechanical thrombectomy for acute ischemic stroke from 2013 to 2018. Of these, 59,935 (66.9%) admissions involved mechanical thrombectomy alone. There was an increase in the trend toward the use of mechanical thrombectomy alone (trend: 3.26%; P < .001) per year. Multivariable regression analysis regarding patient profiles indicated that patients who identified as Black (OR = 0.83, P = .001) or Hispanic (OR = 0.79; P < .001) were more likely to undergo mechanical thrombectomy alone compared with those who identified as White. There was no statistically significant difference in the slope between non-White and White populations receiving mechanical thrombectomy alone (trend: +0.93% in favor of non-White; P = .096).

CONCLUSIONS

Our results indicated that mechanical thrombectomy alone was used more frequently than MT+IV-tPA among patients with acute ischemic stroke. The disparity between those who identify as White and non-White persisted across the years, though it is closing.

Comparison of Outcomes Between Cage Materials Used for Patients Undergoing Anterior Cervical Discectomy and Fusion with Standalone Cages: A Systematic Review and Meta-Analysis

INTRODUCTION

Interbody cages are currently being used to address diseases of the vertebra requiring surgical stabilization. Titanium cages were first introduced in 1988. Polyetheretherketone (PEEK) cages are used frequently as one of the alternatives to titanium cages in current practice. This study aimed to compare available cage materials by reviewing the surgical and radiographic outcomes following anterior cervical discectomy and fusion.

METHODS

A comprehensive search of several electronic databases was conducted following the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. Baseline characteristics, operative outcomes, arthrodesis rates, subsidence rates, and complications were collected from included studies. Collected outcomes were further stratified according to the procedure type, the number of levels operated, and graft used to compare cage materials.

RESULTS

Following the screening for inclusion criteria, a total of 37 studies with 2363 patients were included. The median age was 49.5 years and the median follow-up was 26 months. Overall, no significant differences were found between PEEK and titanium cages regarding fusion, neurologic deficit, subsidence rates, or "good and excellent" outcome according to Odom criteria. However, the standalone comparison between PEEK, titanium, and poly-methyl-methacrylate (PMMA) cages showed a significantly lower fusion rate for PMMA (PEEK: 94%, PMMA: 56%, titanium: 95%, P < 0.01).

CONCLUSIONS

In the present systematic review and meta-analysis, a comparison of the long-term patient-reported and the radiographic outcomes associated with the use of titanium and PEEK, intervertebral body cages showed similar findings. However, there were significantly lower fusion rates for PMMA cages when using a standalone cage without graft material.

Association of ≥ 12 months of delayed surgical treatment for cervical myelopathy with worsened postoperative outcomes: a multicenter analysis of the Quality Outcomes Database

OBJECTIVE

Degenerative cervical myelopathy (DCM) results in significant morbidity. The duration of symptoms prior to surgical intervention may be associated with postoperative surgical outcomes and functional recovery. The authors' objective was to investigate whether delayed surgical treatment for DCM is associated with worsened postoperative outcomes.

METHODS

Data from 1036 patients across 14 surgical centers in the Quality Outcomes Database were analyzed. Baseline demographic characteristics and findings of preoperative and postoperative symptom evaluations, including duration of symptoms, were assessed. Postoperative functional outcomes were measured using the Neck Disability Index (NDI) and modified Japanese Orthopaedic Association (mJOA) scale. Symptom duration was classified as either less than 12 months or 12 months or greater. Univariable and multivariable regression were used to evaluate for the associations between symptom duration and postoperative outcomes.

RESULTS

In this study, 513 patients (49.5%) presented with symptom duration < 12 months, and 523 (50.5%) had symptoms for 12 months or longer. Patients with longer symptom duration had higher BMI and higher prevalence of anxiety and diabetes (all p < 0.05). Symptom duration ≥ 12 months was associated with higher average baseline NDI score (41 vs 36, p < 0.01). However, improvements in NDI scores from baseline were not significantly different between groups at 3 months (p = 0.77) or 12 months (p = 0.51). Likewise, the authors found no significant differences between groups in changes in mJOA scores from baseline to 3 months or 12 months (both p > 0.05).

CONCLUSIONS

Surgical intervention resulted in improved mJOA and NDI scores at 3 months, and this improvement was sustained in both patients with short and longer initial symptom duration. Patients with DCM can still undergo successful surgical management despite delayed presentation.

Hybrid surgery: a comparison of early postoperative outcomes between anterior cervical discectomy and fusion and cervical disc arthroplasty

OBJECTIVE

Hybrid surgery (HS) is the combination of anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) at different levels in the same operation. The aim of this study was to investigate perioperative variables, 30-day postoperative outcomes, and complications of HS in comparison with those of CDA and ACDF.

METHODS

The authors queried the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) registry for patients who underwent multilevel primary HS, CDA, and ACDF for degenerative disc disease from 2015 to 2019. The authors compared these three operations in terms of 30-day postoperative outcomes, specifically readmission and reoperation rates, discharge destination, and complications.

RESULTS

This analysis included 439 patients who underwent HS, 976 patients who underwent CDA, and 27,460 patients who underwent ACDF. Patients in the HS and CDA groups were younger, had fewer comorbidities, and myelopathy was less often the indication for surgery compared with patients who underwent ACDF. For the HS group, the unplanned readmission rate was 0.7%, index surgery-related reoperation rate was 0.3%, and nonroutine discharge rate was 2.1%. Major and minor complications were also rare, with rates of 0.2% for each. The mean length of stay in the HS group was 1.5 days. The association of HS with better outcomes in univariate analysis was not evident after adjustment for confounding factors.

CONCLUSIONS

The authors found that HS was noninferior to ACDF and CDA in terms of early postoperative outcomes among patients treated for degenerative disc disease.

Do all outpatient spine surgeries cost the same? Comparison of economic outcomes data from a state-level database for outpatient lumbar decompression performed in an ambulatory surgery center or hospital outpatient setting

OBJECTIVE

Spinal procedures are increasingly conducted as outpatient procedures, with a growing proportion conducted in ambulatory surgery centers (ASCs). To date, studies reporting outcomes and cost analyses for outpatient spinal procedures in the US have not distinguished the various outpatient settings from each other. In this study, the authors used a state-level administrative database to compare rates of overnight stays and nonroutine discharges as well as index admission charges and cumulative 7-, 30-, and 90-day charges for patients undergoing outpatient lumbar decompression in freestanding ASCs and hospital outpatient (HO) settings.

METHODS

For this project, the authors used the Florida State Ambulatory Surgery Database (SASD), offered by the Healthcare Cost and Utilization Project (HCUP), for the years 2013 and 2014. Patients undergoing outpatient lumbar decompression for degenerative diseases were identified using CPT (Current Procedural Terminology) and ICD-9 codes. Outcomes of interest included rates of overnight stays, rate of nonroutine discharges, index admission charges, and subsequent admission cumulative charges at 7, 30, and 90 days. Multivariable analysis was performed to assess the impact of outpatient type on index admission charges. Marginal effect analysis was employed to study the difference in predicted dollar margins between ASCs and HOs for each insurance type.

RESULTS

A total of 25,486 patients were identified; of these, 7067 patients (27.7%) underwent lumbar decompression in a freestanding ASC and 18,419 (72.3%) in an HO. No patient in the ASC group required an overnight stay compared to 9.2% (n = 1691) in the HO group (p < 0.001). No clinically significant difference in the rate of nonroutine discharge was observed between the two groups. The mean index admission charge for the ASC group was found to be significantly higher than that for the HO group ($35,017.28 ± $14,335.60 vs $33,881.50 ± $15,023.70; p < 0.001). Patients in ASCs were also found to have higher mean 7-day (p < 0.001), 30-day (p < 0.001), and 90-day (p = 0.001) readmission charges. ASC procedures were associated with increased charges compared to HO procedures for patients on Medicare or Medicaid (mean index admission charge increase $4049.27, 95% CI $2577.87-$5520.67, p < 0.001) and for patients on private insurance ($4775.72, 95% CI $4171.06-$5380.38, p < 0.001). For patients on self-pay or no charge, a lumbar decompression procedure at an ASC was associated with a decrease in index admission charge of -$10,995.38 (95% CI -$12124.76 to -$9866.01, p < 0.001) compared to a lumbar decompression procedure at an HO.

CONCLUSIONS

These "real-world" results from an all-payer statewide database indicate that for outpatient spine surgery, ASCs may be associated with higher index admission and subsequent 7-, 30-, and 90-day charges. Given that ASCs are touted to have lower overall costs for patients and better profit margins for physicians, these analyses warrant further investigation into whether this cost benefit is applicable to outpatient spine procedures.

Launching the Quality Outcomes Database Tumor Registry: rationale, development, and pilot data

OBJECTIVE

Neurosurgeons generate an enormous amount of data daily. Within these data lie rigorous, valid, and reproducible evidence. Such evidence can facilitate healthcare reform and improve quality of care. To measure the quality of care provided objectively, evaluating the safety and efficacy of clinical activities should occur in real time. Registries must be constructed and collected data analyzed with the precision akin to that of randomized clinical trials to accomplish this goal.

METHODS

The Quality Outcomes Database (QOD) Tumor Registry was launched in February 2019 with 8 sites in its initial 1-year pilot phase. The Tumor Registry was proposed by the AANS/CNS Tumor Section and approved by the QOD Scientific Committee in the fall of 2018. The initial pilot phase aimed to assess the feasibility of collecting outcomes data from 8 academic practices across the United States; these outcomes included length of stay, discharge disposition, and inpatient complications.

RESULTS

As of November 2019, 923 eligible patients have been entered, with the following subsets: intracranial metastasis (17.3%, n = 160), high-grade glioma (18.5%, n = 171), low-grade glioma (6%, n = 55), meningioma (20%, n = 184), pituitary tumor (14.3%, n = 132), and other intracranial tumor (24%, n = 221).

CONCLUSIONS

The authors have demonstrated here, as a pilot study, the feasibility of documenting demographic, clinical, operative, and patient-reported outcome characteristics longitudinally for 6 common intracranial tumor types.

Impact of predominant symptom location among patients undergoing cervical spine surgery on 12-month outcomes: an analysis from the Quality Outcomes Database

OBJECTIVE

The impact of the type of pain presentation on outcomes of spine surgery remains elusive. The aim of this study was to assess the impact of predominant symptom location (predominant arm pain vs predominant neck pain vs equal neck and arm pain) on postoperative improvement in patient-reported outcomes.

METHODS

The Quality Outcomes Database cervical spine module was queried for patients undergoing 1- or 2-level anterior cervical discectomy and fusion (ACDF) for degenerative spine disease.

RESULTS

A total of 9277 patients were included in the final analysis. Of these patients, 18.4% presented with predominant arm pain, 32.3% presented with predominant neck pain, and 49.3% presented with equal neck and arm pain. Patients with predominant neck pain were found to have higher (worse) 12-month Neck Disability Index (NDI) scores (coefficient 0.24, 95% CI 0.15-0.33; p < 0.0001). The three groups did not differ significantly in odds of return to work and achieving minimal clinically important difference in NDI score at the 12-month follow-up.

CONCLUSIONS

Analysis from a national spine registry showed significantly lower odds of patient satisfaction and worse NDI score at 1 year after surgery for patients with predominant neck pain when compared with patients with predominant arm pain and those with equal neck and arm pain after 1- or 2-level ACDF. With regard to return to work, all three groups (arm pain, neck pain, and equal arm and neck pain) were found to be similar after multivariable analysis. The authors' results suggest that predominant pain location, especially predominant neck pain, might be a significant determinant of improvement in functional outcomes and patient satisfaction after ACDF for degenerative spine disease. In addition to confirmation of the common experience that patients with predominant neck pain have worse outcomes, the authors' findings provide potential targets for improvement in patient management for these specific populations.

Utilization Trends of Recombinant Human Bone Morphogenetic Protein in the United States

STUDY DESIGN

Retrospective.

OBJECTIVE

The aim of this study was to explore the utilization trends of recombinant human bone morphogenetic protein (rh-BMP) in the United States using the largest inpatient administrative database.

SUMMARY OF BACKGROUND DATA

Since 2002, the rh-BMP has been widely used by the surgical spine community in fusion surgery. In light of the rising evidence regarding the safety and efficacy of this novel and expensive bone biological technology, a comprehensive examination of its utilization in the American population is warranted.

METHODS

We queried the 2002-Q3 2015 National Inpatient Sample for patients that underwent spinal fusion with rh-BMP. We calculated population-level estimates of rh-BMP utilization trends per 100,000 spinal fusions. Trends were estimated for the overall use as well as broken down by primary versus revision fusion, fusion type, number of levels, age category, US region, and hospital type.

RESULTS

A total of 5,563,282 fusions were performed, of which 19.9% (n = 1,108,984) utilized rh-BMP. We detected an increase in rh-BMP use in spinal fusion surgery from 0.7% in 2002 to a peak of 29.5% in 2010, followed by a gradual decline till Q3 2015, where it represented 14.7% of all fusion surgeries. These trends paralleled all fusion types. It was most commonly used in fusions spanning two to three levels. The South remained the most common region, whereas West has recently surpassed the Midwest. Its use is becoming more pervasive among older patients, particularly in the 65- to 74 years' age group.

CONCLUSION

Further studies are needed to provide insights into the correlation of these trends with the technology's safety and efficacy profile in contemporary series.Level of Evidence: 3.

Economic Burden of Hospitalizations Associated with Opioid Dependence Among Patients Undergoing Spinal Fusion

BACKGROUND

The current study seeks to examine the association between chronic opioid use and postoperative outcomes for patients undergoing anterior cervical discectomy and fusion (ACDF) and posterior lumbar fusion (PLF).

METHODS

The National Inpatient Sample was queried for patients with and without chronic opioid use undergoing ACDF or PLF for degenerative disc disease between 2012 and 2015 using ICD-9 diagnosis and procedure codes. Multivariable conditional logistic regression was performed to assess the association between chronic opioid use and length of stay (LOS), nonhome discharge, and hospital charge.

RESULTS

A total of 391 patients undergoing ACDF and 644 patients undergoing PLF with opioid dependence were identified. On multivariable regression analysis, opioid dependence was significantly associated with an increased LOS (mean, 3.09 days vs. 2.16 days; odds ratio (OR) for prolonged LOS (>3 days), 2.11; 95% confidence interval [CI], 1.43-3.14; P < 0.001). Although on unadjusted analyses, patients with opioid dependence undergoing ACDF were found to have higher hospital charges (mean, U.S. $18,698.42 vs. $11,378.61; P < 0.001) and higher rates of nonroutine discharge (19.18% vs. 10.21%; P < 0.001), the multivariable regression analyses found no significant association between opioid dependence and odds of hospital charges >75th percentile (OR, 1.44; 95% CI, 0.84-2.47; P = 0.188) or nonroutine discharge (OR, 1.48; 95% CI, 0.93-2.34; P = 0.098). For those undergoing PLF, opioid dependence was significantly associated with increased hospital charges (mean, U.S. $37,712.98 vs. $30,475.43, P < 0.001; OR for hospital charge >75th percentile, 1.78, 95% CL, 1.23-2.58, P = 0.002), LOS (mean, 3.42 days vs. 2.30 days; OR for prolonged LOS, 1.53; 95% CI, 1.16-2.00; P = 0.003), and nonroutine discharge (46.89% vs. 36.47%; OR, 1.74; 95% CI, 1.34-2.26; P < 0.001) on both unadjusted and adjusted multivariable regression analyses.

CONCLUSIONS

Our analysis using a national administrative database showed that opioid dependence may be associated with worse economic outcomes for patients undergoing ACDF and PLF.

Assessing the Differences in Measurement of Degree of Spondylolisthesis Between Supine MRI and Erect X-Ray: An Institutional Analysis of 255 Cases

BACKGROUND

Degenerative spondylolisthesis is the displacement of one vertebral body over the adjacent one. While standing and flexion-extension X-rays are preferred for determining listhesis, magnetic resonance imaging (MRI) is often utilized to assess the compression of nerve root or spinal cord.

OBJECTIVE

To investigate the difference in radiographic measurements of spondylolisthesis between X-rays and MRI.

METHODS

We retrospectively reviewed the records and radiographic images of patients with a confirmed diagnosis of spondylolisthesis undergoing operation in 2016. Primary variable of interest was the degree of slippage as per the Meyerding method. Agreement between the 2 reviewers was assessed using the 2-way intraclass correlation coefficient (ICC) for slippage percentage and Cohen's Kappa for grade. Agreement of Meyerding grade between the 2 imaging techniques was assessed using Cohen's Kappa, while the slip percentage measured for each technique was compared using a Bland-Altman (BA) plot, mean difference (MD), and 1-way ICC.

RESULTS

A total of 255 cases were analyzed. ICC between the 2 reviewers was found to be 0.75 (95% confidence interval [CI] = 0.64-0.83, P < .001) for X-ray and 0.76 (95% CI = 0.66-0.83, P < .001) for MRI. Agreement between X-ray and MRI for grading of spondylolisthesis was found to be poor (kappa = 0.32, P < .001). BA plot between X-ray and MRI measurements revealed an MD of 4.4% (95% limits of agreement: -10.3% to 19.3%) with 5.16% observations outside the limits of agreement and 1-way ICC of 0.35 showing poor agreement.

CONCLUSION

Our results demonstrate the discrepancy of spondylolisthesis grade measurements between weight-bearing X-ray and nonweight-bearing MRI. Careful evaluation of both imaging technique is warranted to determine the final severity of pathology and tailoring of management plan.

Impact of Opioid Prescribing Guidelines on Postoperative Opioid Prescriptions Following Elective Spine Surgery: Results From an Institutional Quality Improvement Initiative

BACKGROUND

With a dramatic rise in prescription opioid use, it is imperative to review postsurgical prescribing patterns given their contributions to the opioid epidemic.

OBJECTIVE

To evaluate the impact of departmental postoperative prescribing guidelines on opioid prescriptions following elective spine surgery.

METHODS

Patients undergoing elective cervical or lumbar spine surgery between 2017 and 2018 were identified. Procedure-specific opioid prescribing guidelines to limit postoperative prescribing following neurosurgical procedures were developed in 2017 and implemented in January 2018. Preguideline data were available from July to December 2017, and postguideline data from July to December 2018. Discharge prescriptions in morphine milliequivalents (MMEs), the proportion of patients (i) discharged with an opioid prescription, (ii) needing refills within 30 d, (iii) with guideline compliant prescriptions were compared in the 2 groups. Multivariable (MV) analyses were performed to assess the impact of guideline implementation on refill prescriptions within 30 d.

RESULTS

A total of 1193 patients were identified (cervical: 308; lumbar: 885) with 569 (47.7%) patients from the preguideline period. Following guideline implementation, fewer patients were discharged with a postoperative opioid prescription (92.5% vs 81.7%, P < .001) and median postoperative opioid prescription decreased significantly (300 MMEs vs 225 MMEs, P < .001). The 30-d refill prescription rate was not significantly different between preguideline and postguideline cohorts (pre: 24.4% vs post: 20.2%, P = .079). MV analyses did not demonstrate any impact of guideline implementation on need for 30-d refill prescriptions for both cervical (odds ratio [OR] = 0.68, confidence interval [CI] = 0.37-1.26, P = .22) and lumbar cohorts (OR = 0.95, CI = 0.66-1.36, P = .78).

CONCLUSION

Provider-aimed interventions such as implementation of procedure-specific prescribing guidelines can significantly reduce postoperative opioid prescriptions following spine surgery without increasing the need for refill prescriptions for pain control.

Laser Interstitial Thermal Therapy for Recurrent Glioblastoma: Pooled Analyses of Available Literature

OBJECTIVE/BACKGROUND

The efficacy of laser interstitial thermal therapy (LITT) in recurrent glioblastoma (rGBM) is unknown. The goal of this study was to conduct a systematic review and pooled analysis of the literature for outcomes on patients with rGBM undergoing LITT.

METHODS

A literature search was performed to retrieve all studies investigating overall survival, postprocedure survival, and progression-free survival outcomes of patients with rGBM undergoing LITT. Statistics were pooled together by meta-analysis of mean using a weighted random-effects or fixed-effect model.

RESULTS

Eleven studies were included in the final cohort, representing a total of 134 patients with rGBM. The pooled mean age of the cohort at the time of recurrence was 56.7 ± 4.56 years; 41% of the cohort were female. For delivery of LITT, 2 studies used neodymium-yttrium aluminum-garnet laser (Nd:YAG laser), 3 studies used the Visualase system, 5 studies used the NeuroBlate system, and 1 study used both the NeuroBlate and the Visualase system. A total of 8 studies with 107 patients had available data for overall median survival. The pooled overall survival was found to be 18.6 months (95% confidence interval [CI] 16.2-21.1). A total of 6 studies with 93 patients had available data for post-LITT survival. The pooled post-LITT survival was found to be 10.1 months (95% CI 8.8-11.6). A total of 8 studies with 119 patients had available data for progression-free survival. Pooled progression free survival was found to be 6 months (95% CI 5.3-6.7).

CONCLUSIONS

LITT is a novel minimally invasive procedure which, when used with optimal adjuvant therapy, may confer survival benefit for patients with rGBM.

Clinical characteristics and management differences for grade II and III spinal meningiomas

PURPOSE

The majority of spinal meningiomas are grade I tumors, as defined by World Health Organization (WHO) classification making atypical (grade II) or anaplastic (grade III) tumors extremely rare lesions to encounter in clinical practice. Here, we present our institutional experience of management of grade II and III spinal meningiomas.

METHODS

Following IRB approval, we queried all available institutional electronic medical records for patients undergoing surgical resection of pathology-proven spinal meningiomas, with further review of patients with grade II and III. Variables of interest included age, sex, histological type, tumor size, symptoms at baseline, treatment characteristics, symptom resolution at the last follow-up, recurrence, NF-2 status, concurrent intracranial meningioma, and mortality. Kaplan Meier curves were constructed to study time to progression/recurrence.

RESULTS

A total of 188 patients undergoing surgical resection of spinal meningioma between 1988 and 2018 were identified. Among those, 172 (91.5%) patients had grade I meningioma and 16 (8.5%) patients had high grade meningiomas [grade II (15) and III (1)]. Over a median (IQR) follow-up of 8.0 years (5.1-13.0), mortality and recurrence rates were 18.8% (n = 3) and 47.1% (n = 8), respectively. In univariate analysis, adjuvant radiotherapy and thoracic segment involvement were associated with lower rates of recurrence while male sex was associated with a higher rate of recurrence.

CONCLUSIONS

Results showed variations in clinical outcomes for patients with high grade spinal meningiomas, especially the recurrence. Adjuvant radiotherapy and thoracic segment involvement was associated with lower rates of recurrence while recurrence ocurred at a higher rate in males.

Identifying patients at risk for nonroutine discharge after surgery for cervical myelopathy: an analysis from the Quality Outcomes Database

OBJECTIVE

Optimizing patient discharge after surgery has been shown to impact patient recovery and hospital/physician workflow and to reduce healthcare costs. In the current study, the authors sought to identify risk factors for nonroutine discharge after surgery for cervical myelopathy by using a national spine registry.

METHODS

The Quality Outcomes Database cervical module was queried for patients who had undergone surgery for cervical myelopathy between 2016 and 2018. Nonroutine discharge was defined as discharge to postacute care (rehabilitation), nonacute care, or another acute care hospital. A multivariable logistic regression predictive model was created using an array of demographic, clinical, operative, and patient-reported outcome characteristics.

RESULTS

Of the 1114 patients identified, 11.2% (n = 125) had a nonroutine discharge. On univariate analysis, patients with a nonroutine discharge were more likely to be older (age ≥ 65 years, 70.4% vs 35.8%, p < 0.001), African American (24.8% vs 13.9%, p = 0.007), and on Medicare (75.2% vs 35.1%, p < 0.001). Among the patients younger than 65 years of age, those who had a nonroutine discharge were more likely to be unemployed (70.3% vs 36.9%, p < 0.001). Overall, patients with a nonroutine discharge were more likely to present with a motor deficit (73.6% vs 58.7%, p = 0.001) and more likely to have nonindependent ambulation (50.4% vs 14.0%, p < 0.001) at presentation. On multivariable logistic regression, factors associated with higher odds of a nonroutine discharge included African American race (vs White, OR 2.76, 95% CI 1.38-5.51, p = 0.004), Medicare coverage (vs private insurance, OR 2.14, 95% CI 1.00-4.65, p = 0.04), nonindependent ambulation at presentation (OR 2.17, 95% CI 1.17-4.02, p = 0.01), baseline modified Japanese Orthopaedic Association severe myelopathy score (0-11 vs moderate 12-14, OR 2, 95% CI 1.07-3.73, p = 0.01), and posterior surgical approach (OR 11.6, 95% CI 2.12-48, p = 0.004). Factors associated with lower odds of a nonroutine discharge included fewer operated levels (1 vs 2-3 levels, OR 0.3, 95% CI 0.1-0.96, p = 0.009) and a higher quality of life at baseline (EQ-5D score, OR 0.43, 95% CI 0.25-0.73, p = 0.001). On predictor importance analysis, baseline quality of life (EQ-5D score) was identified as the most important predictor (Wald χ2 = 9.8, p = 0.001) of a nonroutine discharge; however, after grouping variables into distinct categories, socioeconomic and demographic characteristics (age, race, gender, insurance status, employment status) were identified as the most significant drivers of nonroutine discharge (28.4% of total predictor importance).

CONCLUSIONS

The study results indicate that socioeconomic and demographic characteristics including age, race, gender, insurance, and employment may be the most significant drivers of a nonroutine discharge after surgery for cervical myelopathy.