Lumbar Decompression with and without Fusion for Lumbar Stenosis with Spondylolisthesis: A Cost Utility Analysis

STUDY DESIGN

Markov model.

OBJECTIVE

To compare the cost-effectiveness of lumbar decompression alone (DA) with lumbar decompression with fusion (DF) for the management of adults undergoing surgery for lumbar stenosis with associated degenerative spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Rates of lumbar fusion have increased for all indications in the United States over the last 20 years. Recent randomized controlled trial data, however, have suggested comparable functional outcomes and lower reoperation rates for lumbar decompression and fusion as compared to lumbar decompression alone in the treatment of lumbar stenosis with degenerative spondylolisthesis.

MATERIALS AND METHODS

A multi-state Markov model was constructed from the U.S. payer perspective of a hypothetical cohort of patients with LSS requiring surgery. Data regarding clinical improvement, costs, and reoperation were generated from contemporary randomized trial evidence, meta-analyses of recent prospective studies, and large retrospective cohorts. Base case, one-way sensitivity analysis, and probabilistic sensitivity analyses were conducted and results were compared to a willingness to pay threshold of $100,000 (in 2022 USD) over a 2-year time horizon. A discount rate of 3% was utilized.

RESULTS

The incremental cost and utility of decompression with fusion relative to decompression alone were $12,778 and 0.00529 QALYs. The corresponding ICER of $2,416,281 far exceeded a willingness to pay threshold of $100,000. In sensitivity analysis, the results varied the most with respect to rate of improvement after lumbar decompression alone, rate of improvement after lumbar decompression and fusion, and odds ratio of reoperation between the two groups. 0% of one-way and probabilistic sensitivity analyses achieved cost-effectiveness at the willingness to pay threshold.

CONCLUSIONS

Within the context of contemporary surgical data, DF is not cost effective compared with DA in the surgical management of LSS over a 2-year time horizon.

Performance of ChatGPT and GPT-4 on Neurosurgery Written Board Examinations

BACKGROUND AND OBJECTIVES

Interest surrounding generative large language models (LLMs) has rapidly grown. Although ChatGPT (GPT-3.5), a general LLM, has shown near-passing performance on medical student board examinations, the performance of ChatGPT or its successor GPT-4 on specialized examinations and the factors affecting accuracy remain unclear. This study aims to assess the performance of ChatGPT and GPT-4 on a 500-question mock neurosurgical written board examination.

METHODS

The Self-Assessment Neurosurgery Examinations (SANS) American Board of Neurological Surgery Self-Assessment Examination 1 was used to evaluate ChatGPT and GPT-4. Questions were in single best answer, multiple-choice format. χ 2 , Fisher exact, and univariable logistic regression tests were used to assess performance differences in relation to question characteristics.

RESULTS

ChatGPT (GPT-3.5) and GPT-4 achieved scores of 73.4% (95% CI: 69.3%-77.2%) and 83.4% (95% CI: 79.8%-86.5%), respectively, relative to the user average of 72.8% (95% CI: 68.6%-76.6%). Both LLMs exceeded last year's passing threshold of 69%. Although scores between ChatGPT and question bank users were equivalent ( P = .963), GPT-4 outperformed both (both P < .001). GPT-4 answered every question answered correctly by ChatGPT and 37.6% (50/133) of remaining incorrect questions correctly. Among 12 question categories, GPT-4 significantly outperformed users in each but performed comparably with ChatGPT in 3 (functional, other general, and spine) and outperformed both users and ChatGPT for tumor questions. Increased word count (odds ratio = 0.89 of answering a question correctly per +10 words) and higher-order problem-solving (odds ratio = 0.40, P = .009) were associated with lower accuracy for ChatGPT, but not for GPT-4 (both P > .005). Multimodal input was not available at the time of this study; hence, on questions with image content, ChatGPT and GPT-4 answered 49.5% and 56.8% of questions correctly based on contextual context clues alone.

CONCLUSION

LLMs achieved passing scores on a mock 500-question neurosurgical written board examination, with GPT-4 significantly outperforming ChatGPT.

Optimizing surgical management of facet cysts of the lumbar spine: systematic review, meta-analysis, and local case series of 1251 patients

OBJECTIVE

Lumbar facet cysts (LFCs) can cause neurological dysfunction and intractable pain. Surgery is the current standard of care for patients in whom conservative therapy fails, those with neurological deficits, and those with evidence of spinal instability. No study to date has comprehensively examined surgical outcomes comparing the multiple surgical treatment options for LFCs. Therefore, the authors aimed to perform a combined analysis of cases both in the literature and of patients at a single institution to compare the outcomes of various surgical treatment options for LFC.

METHODS

The authors performed a literature review in accordance with PRISMA guidelines and meta-analysis of the PubMed, Embase, and Cochrane Library databases and reviewed all studies from database inception published until February 3, 2023. Studies that did not contain 3 or more cases, clearly specify follow-up durations longer than 6 months, or present new cases were excluded. Bias was evaluated using Cochrane Collaboration's Risk of Bias in Nonrandomised Studies-of Interventions (ROBINS-I). The authors also reviewed their own local institutional case series from 2015 to 2020. Primary outcomes were same-level cyst recurrence, same-level revision surgery, and perioperative complications. ANOVA, common and random-effects modeling, and Wald testing were used to compare treatment groups.

RESULTS

A total of 1251 patients were identified from both the published literature (29 articles, n = 1143) and the authors' institution (n = 108). Patients were sorted into 5 treatment groups: open cyst resection (OCR; n = 720), tubular cyst resection (TCR; n = 166), cyst resection with arthrodesis (CRA; n = 165), endoscopic cyst resection (ECR; n = 113), and percutaneous cyst rupture (PCR; n = 87), with OCR being the analysis reference group. The PCR group had significantly lower complication rates (p = 0.004), higher recurrence rates (p < 0.001), and higher revision surgery rates (p = 0.001) compared with the OCR group. Patients receiving TCR (3.01%, p = 0.021) and CRA (0.0%, p < 0.001) had significantly lower recurrence rates compared with those undergoing OCR (6.36%). The CRA group (6.67%) also had significantly lower rates of revision surgery compared with the OCR group (11.3%, p = 0.037).

CONCLUSIONS

While PCR is less invasive, it may have high rates of same-level recurrence and revision surgery. Recurrence and revision rates for modalities such as ECR were not significantly different from those of OCR. While concomitant arthrodesis is more invasive, it might lead to lower recurrence rates and lower rates of subsequent revision surgery. Given the limitations of our case series and literature review, prospective, randomized studies are needed.

Early Outcomes of Muscle Flap Closures in Posterior Thoracolumbar Fusions: A Propensity-Matched Cohort Analysis

BACKGROUND

Plastic surgery closure with muscle flaps after complex spinal reconstruction has become increasingly common. Existing evidence for this practice consists of small, uncontrolled, single-center cohort studies. We aimed to compare 30-day postoperative wound-related complication rates between flap closure and traditional closure after posterior thoracolumbar fusions (PTLFs) for non-infectious, non-oncologic pathologies using a national database.

METHODS

We performed a propensity-matched analysis using the 2012-2020 National Surgical Quality Improvement Program dataset to compare 30-day outcomes between PTLFs with flap closure versus traditional closure.

RESULTS

A total of 100,799 PTLFs met our inclusion criteria. The use of flap closure with PTLF remained low but more than doubled from 2012 to 2020 (0.38% vs. 0.97%; P = 0.002). A higher proportion of flap closures had higher American Society of Anesthesiologists classifications and higher number of operated spine levels (all P < 0.001). We included 1907 PTLFs (630 for flap closure; 1257 for traditional closure) in the propensity-matched cohort. Unadjusted 30-day wound complication rates were 1.7% for flap and 2.1% for traditional closure (P = 0.76). After adjusting for operative time, wound complication, readmission, reoperation, mortality, and non-wound complication were not associated flap use (all P > 0.05).

CONCLUSIONS

Plastic surgery closure was performed in patients with a higher comorbidity burden, suggesting consultation in sicker patients. Although higher rates of wound and non-wound complications were expected for the flap cohort, our propensity-matched cohort analysis of flap closure in PTLFs resulted in non-inferior odds of wound complications compared to traditional closure. Further study is needed to assess long-term complications in prophylactic flap closure in complex spine surgeries.

Performance of ChatGPT, GPT-4, and Google Bard on a Neurosurgery Oral Boards Preparation Question Bank

BACKGROUND AND OBJECTIVES

General large language models (LLMs), such as ChatGPT (GPT-3.5), have demonstrated the capability to pass multiple-choice medical board examinations. However, comparative accuracy of different LLMs and LLM performance on assessments of predominantly higher-order management questions is poorly understood. We aimed to assess the performance of 3 LLMs (GPT-3.5, GPT-4, and Google Bard) on a question bank designed specifically for neurosurgery oral boards examination preparation.

METHODS

The 149-question Self-Assessment Neurosurgery Examination Indications Examination was used to query LLM accuracy. Questions were inputted in a single best answer, multiple-choice format. χ 2 , Fisher exact, and univariable logistic regression tests assessed differences in performance by question characteristics.

RESULTS

On a question bank with predominantly higher-order questions (85.2%), ChatGPT (GPT-3.5) and GPT-4 answered 62.4% (95% CI: 54.1%-70.1%) and 82.6% (95% CI: 75.2%-88.1%) of questions correctly, respectively. By contrast, Bard scored 44.2% (66/149, 95% CI: 36.2%-52.6%). GPT-3.5 and GPT-4 demonstrated significantly higher scores than Bard (both P < .01), and GPT-4 outperformed GPT-3.5 ( P = .023). Among 6 subspecialties, GPT-4 had significantly higher accuracy in the Spine category relative to GPT-3.5 and in 4 categories relative to Bard (all P < .01). Incorporation of higher-order problem solving was associated with lower question accuracy for GPT-3.5 (odds ratio [OR] = 0.80, P = .042) and Bard (OR = 0.76, P = .014), but not GPT-4 (OR = 0.86, P = .085). GPT-4's performance on imaging-related questions surpassed GPT-3.5's (68.6% vs 47.1%, P = .044) and was comparable with Bard's (68.6% vs 66.7%, P = 1.000). However, GPT-4 demonstrated significantly lower rates of "hallucination" on imaging-related questions than both GPT-3.5 (2.3% vs 57.1%, P < .001) and Bard (2.3% vs 27.3%, P = .002). Lack of question text description for questions predicted significantly higher odds of hallucination for GPT-3.5 (OR = 1.45, P = .012) and Bard (OR = 2.09, P < .001).

CONCLUSION

On a question bank of predominantly higher-order management case scenarios for neurosurgery oral boards preparation, GPT-4 achieved a score of 82.6%, outperforming ChatGPT and Google Bard.

Patterns in Decompression and Fusion Procedures for Patients With Lumbar Stenosis After Major Clinical Trial Results, 2016 to 2019

Importance

Use of lumbar fusion has increased substantially over the last 2 decades. For patients with lumbar stenosis and degenerative spondylolisthesis, 2 landmark prospective randomized clinical trials (RCTs) published in the New England Journal of Medicine in 2016 did not find clear evidence in favor of decompression with fusion over decompression alone in this population.

Objective

To assess the national use of decompression with fusion vs decompression alone for the surgical treatment of lumbar stenosis and degenerative spondylolisthesis from 2016 to 2019.

Design, Setting, and Participants

This retrospective cohort study included 121 745 hospitalized adult patients (aged ≥18 years) undergoing 1-level decompression alone or decompression with fusion for the management of lumbar stenosis and degenerative spondylolisthesis from January 1, 2016, to December 31, 2019. All data were obtained from the National Inpatient Sample (NIS). Analyses were conducted, reviewed, or updated on June 9, 2023.

Main Outcome and Measure

The primary outcome of this study was the use of decompression with fusion vs decompression alone. For the secondary outcome, multivariable logistic regression analysis was used to evaluate factors associated with the decision to perform decompression with fusion vs decompression alone.

Results

Among 121 745 eligible hospitalized patients (mean age, 65.2 years [95% CI, 65.0-65.4 years]; 96 645 of 117 640 [82.2%] non-Hispanic White) with lumbar stenosis and degenerative spondylolisthesis, 21 230 (17.4%) underwent decompression alone, and 100 515 (82.6%) underwent decompression with fusion. The proportion of patients undergoing decompression alone decreased from 2016 (7625 of 23 405 [32.6%]) to 2019 (3560 of 37 215 [9.6%]), whereas the proportion of patients undergoing decompression with fusion increased over the same period (from 15 780 of 23 405 [67.4%] in 2016 to 33 655 of 37 215 [90.4%] in 2019). In univariable analysis, patients undergoing decompression alone differed significantly from those undergoing decompression with fusion with regard to age (mean, 68.6 years [95% CI, 68.2-68.9 years] vs 64.5 years [95% CI, 64.3-64.7 years]; P < .001), insurance status (eg, Medicare: 13 725 of 21 205 [64.7%] vs 53 320 of 100 420 [53.1%]; P < .001), All Patient Refined Diagnosis Related Group risk of death (eg, minor risk: 16 900 [79.6%] vs 83 730 [83.3%]; P < .001), and hospital region of the country (eg, South: 7030 [33.1%] vs 38 905 [38.7%]; Midwest: 4470 [21.1%] vs 23 360 [23.2%]; P < .001 for both comparisons). In multivariable logistic regression analysis, older age (adjusted odds ratio [AOR], 0.96 per year; 95% CI, 0.95-0.96 per year), year after 2016 (AOR, 1.76 per year; 95% CI, 1.69-1.85 per year), self-pay insurance status (AOR, 0.59; 95% CI, 0.36-0.95), medium hospital size (AOR, 0.77; 95% CI, 0.67-0.89), large hospital size (AOR, 0.76; 95% CI, 0.67-0.86), and highest median income quartile by patient residence zip code (AOR, 0.79; 95% CI, 0.70-0.89) were associated with lower odds of undergoing decompression with fusion. Conversely, hospital region in the Midwest (AOR, 1.34; 95% CI, 1.14-1.57) or South (AOR, 1.32; 95% CI, 1.14-1.54) was associated with higher odds of undergoing decompression with fusion. Decompression with fusion vs decompression alone was associated with longer length of stay (mean, 2.96 days [95% CI, 2.92-3.01 days] vs 2.55 days [95% CI, 2.49-2.62 days]; P < .001), higher total admission costs (mean, $30 288 [95% CI, $29 386-$31 189] vs $16 190 [95% CI, $15 189-$17 191]; P < .001), and higher total admission charges (mean, $121 892 [95% CI, $119 566-$124 219] vs $82 197 [95% CI, $79 745-$84 648]; P < .001).

Conclusions and Relevance

In this cohort study, despite 2 prospective RCTs that demonstrated the noninferiority of decompression alone compared with decompression with fusion, use of decompression with fusion relative to decompression alone increased from 2016 to 2019. A variety of patient- and hospital-level factors were associated with surgical procedure choice. These results suggest the findings of 2 major RCTs have not yet produced changes in surgical practice patterns and deserve renewed focus.

Time of Discharge and 30-Day Re-Presentation to an Acute Care Setting After Elective Lumbar Decompression Surgery

BACKGROUND

Evidence regarding the consequence of efforts to increase patient throughput and decrease length of stay in the context of elective spine surgery is limited.

OBJECTIVE

To evaluate whether early time of discharge results in increased rates of hospital readmission or return to emergency department for patients admitted after elective, posterior, lumbar decompression surgery.

METHODS

We conducted a retrospective cohort study of 779 patients admitted to hospital after undergoing elective, posterior, lumbar decompression surgery. Multiple logistic regression evaluated the relationship between time of discharge and the primary outcome of return to acute care within 30 days, while controlling for sociodemographic, procedural, and discharge characteristics.

RESULTS

In multiple logistic regression, time of discharge earlier in the day was not associated with increased odds of return to acute care within 30 days (odds ratio [OR] 1.18, 95% CI 0.92-1.52, P = .19). Weekend discharge (OR 1.99, 95% CI 1.04-3.79, P = .04) increased the likelihood of return to acute care. Surgeon experience (<1 year of attending practice, OR 0.43, 95% CI 0.19-1.00, P = .05 and 2-5 years of attending practice, OR 0.50, 95% CI 0.25-1.01, P = .054), weekend discharge (OR 0.49, 95% CI 0.27-0.89, P = .02), and physical therapy evaluation (OR 0.20, 95% CI 0.12-0.33, P < .001) decreased the likelihood of discharge before noon.

CONCLUSION

Time of discharge is not associated with risk of readmission or presentation to the emergency department after elective lumbar decompression. Weekend discharge is independently associated with increased risk of readmission and decreased likelihood of prenoon discharge.

Long-Term Motor versus Sensory Lumbar Plexopathy After Lateral Lumbar Interbody Fusion: Single-Center Experience, Intraoperative Neuromonitoring Results, and Multivariate Analysis of Patient-Level Predictors

BACKGROUND

Although lateral lumbar interbody fusion (LLIF) is an effective surgical option for lumbar arthrodesis, postoperative plexopathies are a common complication. We characterized post-LLIF plexopathies in a large cohort and analyzed potential risk factors for each.

METHODS

A single-institutional cohort who underwent LLIF between May 2015 and December 2019 was retrospectively reviewed for postoperative lumbar plexopathies. Plexopathies were divided based on sensory and motor symptoms and duration, as well as by laterality relative to the surgical approach. We assessed these subgroups for associations with patient and surgical characteristics as well as psoas dimensions. We then evaluated risk of developing plexopathies after intraoperative neuromonitoring observations.

RESULTS

A total of 127 patients were included. The overall rate of LLIF-induced sensory or motor lumbar plexopathy was 37.8% (48/127). Of all cases, 42 were ipsilateral to the surgical approach (33.1%); conversely, 6 patients developed contralateral plexopathies (4.7%). Most (31/48; 64.6%) resolved with a follow-up interval of 402 days in the plexopathy group. Of ipsilateral cases, 24 patients experienced persistent (>90 days) postoperative sensory symptoms (18.9%), whereas 20 experienced persistent weakness (15.7%). More levels fused predicted persistent sensory symptoms (odds ratio, 1.714 [1.246-2.359]; P = 0.0085), whereas surgical duration predicted persistent weakness (odds ratio, 1.004 [1.002-1.006]; P = 0.0382). Psoas anatomic variables were not significantly associated with plexopathy. Nonresolution of intraoperative evoked motor potential alerts was a significant risk factor for developing plexopathies (relative risk, 2.29 [1.17-4.45]).

CONCLUSIONS

Post-LLIF plexopathies are common but usually resolve. Surgical complexity and unresolved neuromonitoring alerts are possible risk factors for persistent plexopathy.

The New England Neurosurgical Society: growth and evolution over 70 years

The New England Neurosurgical Society (NENS) was founded in 1951 under the leadership of its first President (Dr. William Beecher Scoville) and Secretary-Treasurer (Dr. Henry Thomas Ballantine). The purpose of creating the NENS was to unite local neurosurgeons in the New England area; it was one of the first regional neurosurgical societies in America. Although regional neurosurgical societies are important supplements to national organizations, they have often been overshadowed in the available literature. Now in its 70th year, the NENS continues to serve as a platform to represent the needs of New England neurosurgeons, foster connections and networks with colleagues, and provide research and educational opportunities for trainees. Additionally, regional societies enable discussion of issues uniquely relevant to the region, improve referral patterns, and allow for easier attendance with geographic proximity. In this paper, the authors describe the history of the NENS and provide a roadmap for its future. The first section portrays the founders who led the first meetings and establishment of the NENS. The second section describes the early years of the NENS and profiles key leaders. The third section discusses subsequent neurosurgeons who steered the NENS and partnerships with other societies. In the fourth section, the modern era of the NENS and its current activities are highlighted.

Influence of socioeconomic factors on discharge disposition following traumatic cervicothoracic spinal cord injury at level I and II trauma centers in the United States

BACKGROUND

Discharge to acute rehabilitation is strongly correlated with functional recovery after traumatic injury, including spinal cord injury (SCI). However, services such as acute care rehabilitation and Skilled Nursing Facilities (SNF) are expensive. Our objective was to understand if high-cost, resource-intensive post-discharge rehabilitation or alternative care facilities are utilized at disparate rates across socioeconomic groups after SCI.

METHODS

We performed a cohort analysis using the National Trauma Data Bank® tabulated from 2012-2016. Eligible patients had a diagnosis of cervical or thoracic spine fracture with spinal cord injury (SCI) and were treated surgically. We evaluated associations of sociodemographic and psychosocial variables with non-home discharge (e.g., discharge to SNF, other healthcare facility, or intermediate care facility) via multivariable logistic regression while correcting for injury severity and hospital characteristics.

RESULTS

We identified 3933 eligible patients. Patients who were older, male (OR=1.29 95% Confidence Interval [1.07-1.56], p=.007), insured by Medicare (OR=1.45 [1.08-1.96], p=.015), diagnosed with a major psychiatric disorder (OR=1.40 [1.03-1.90], p=.034), had a higher Injury Severity Score (OR=5.21 [2.96-9.18], p<.001) or a lower Glasgow Coma Score (3-8 points, OR=2.78 [1.81-4.27], p<.001) had a higher chance of a non-home discharge. The only sociodemographic variable associated with lower likelihood of utilizing additional healthcare facilities following discharge was uninsured status (OR=0.47 [0.37-0.60], p<.001).

CONCLUSIONS

Uninsured patients are less likely to be discharged to acute rehabilitation or alternative healthcare facilities following surgical management of SCI. High out-of-pocket costs for uninsured patients in the United States may deter utilization of these services.

Continued underrepresentation of historically excluded groups in the neurosurgery pipeline: an analysis of racial and ethnic trends across stages of medical training from 2012 to 2020

OBJECTIVE

US allopathic medical schools have experienced improvements in racial and ethnic diversity among matriculants in the past decade. It is not clear, however, whether better representation of historically excluded racial and ethnic groups at medical school entry impacts subsequent stages of the medical training pipeline leading into a specific field. The aim of this study was to examine these trends as they relate to the neurosurgical medical education pipeline and consider the drivers that sustain barriers for underrepresented groups.

METHODS

Race and ethnicity reports from the American Association of Medical Colleges were obtained on allopathic medical school applicants, acceptees, and graduates and applicants to US neurosurgical residency programs from 2012 to 2020. The representation of groups categorized by self-reported race and ethnicity was compared with their US population counterparts to determine the representation quotient (RQ) for each group. Annual racial composition differences and changes in representation over time at each stage of medical training were evaluated by estimating incidence rate ratios (IRRs) and 95% confidence intervals (CIs) using non-Hispanic Whites as the reference group.

RESULTS

On average, Asian and White individuals most frequently applied and were accepted to medical school, had the highest graduation rates, and applied to neurosurgery residency programs more often than other racial groups. The medical school application and acceptance rates for Black individuals increased from 2012 to 2020 relative to Whites by 30% (95% CI 1.23-1.36) and 42% (95% CI 1.31-1.53), respectively. During this same period, however, inequities in neurosurgical residency applications grew across all non-Asian racialized groups relative to Whites. While the incidence of active Black neurosurgery residents increased from 2012 to 2020 (0.6 to 0.7/100,000 Black US inhabitants), the prevalence of White neurosurgery residents grew in the active neurosurgery resident population by 16% more.

CONCLUSIONS

The increased racial diversity of medical school students in recent years is not yet reflected in racial representation among neurosurgery applicants. Disproportionately fewer Black relative to White US medical students apply to neurosurgery residency, which contributes to declining racial representation among all active neurosurgery resident physicians. Hispanic individuals are becoming increasingly represented in neurosurgery residency but continue to remain underrepresented relative to the US population. Ongoing efforts to recruit medical students into neurosurgery who more accurately reflect the diversity of the general US population are necessary to ensure equitable patient care.

Frailty independently predicts unfavorable discharge in non-operative traumatic brain injury: A retrospective single-institution cohort study

BACKGROUND

Frailty is associated with adverse outcomes in traumatically injured geriatric patients but has not been well-studied in geriatric Traumatic Brain Injury (TBI).

OBJECTIVE

To assess relationships between frailty and outcomes after TBI.

METHODS

The records of all patients aged 70 or older admitted from home to the neurosurgical service of a single institution for non-operative TBI between January 2020 and July 2021 were retrospectively reviewed. The primary outcome was adverse discharge disposition (either in-hospital expiration or discharge to skilled nursing facility (SNF), hospice, or home with hospice). Secondary outcomes included major inpatient complication, 30-day readmission, and length of stay.

RESULTS

100 patients were included, 90% of whom presented with Glasgow Coma Score (GCS) 14-15. The mean length of stay was 3.78 days. 7% had an in-hospital complication, and 44% had an unfavorable discharge destination. 49% of patients attended follow-up within 3 months. The rate of readmission within 30 days was 13%. Patients were characterized as low frailty (FRAIL score 0-1, n = 35, 35%) or high frailty (FRAIL score 2-5, n = 65, 65%). In multivariate analysis controlling for age and other factors, frailty category (aOR 2.63, 95CI [1.02, 7.14], p = 0.005) was significantly associated with unfavorable discharge. Frailty was not associated with increased readmission rate, LOS, or rate of complications on uncontrolled univariate analyses.

CONCLUSION

Frailty is associated with increased odds of unfavorable discharge disposition for geriatric patients admitted with TBI.

Influence of Sociodemographic and Psychosocial Factors on Length of Stay After Surgical Management of Traumatic Spine Fracture with Spinal Cord Injury

OBJECTIVE

Identifying patients at risk of increased health care resource utilization is a valuable opportunity to develop targeted preoperative and perioperative interventions. In the present investigation, we sought to examine patient sociodemographic factors that predict prolonged length of stay (LOS) after traumatic spine fracture.

METHODS

We performed a cohort analysis using the National Trauma Data Bank tabulated during 2012-2016. Eligible patients were those who were diagnosed with cervical or thoracic spine fracture with spinal cord injury and who were treated surgically. We evaluated the effects of sociodemographic as well as psychosocial variables on LOS by negative binomial regression and adjusted for injury severity, injury mechanism, and hospital characteristics.

RESULTS

We identified 3856 eligible patients with a median LOS of 9 days (interquartile range, 6-15 days). Patients in older age categories, who were male (incidence rate ratio (IRR), 1.05; 95% confidence interval [CI], 1.01-1.09), black (IRR, 1.12; CI, 1.05-1.19) or Hispanic (IRR, 1.09; CI, 1.03-1.16), insured by Medicaid (IRR, 1.24; CI, 1.17-1.31), or had a diagnosis of alcohol use disorder (IRR, 1.12; CI, 1.06-1.18) were significantly more likely to have a longer LOS. In addition, patients with severe injury on Injury Severity Score (IRR, 1.32; CI, 1.14-1.53) and lower Glasgow Coma Scale (GCS) scores (GCS score 3-8, IRR, 1.44; CI, 1.35-1.55; GCS score 9-11, IRR, 1.40; CI, 1.25-1.58) on admission had a significantly lengthier LOS. Patients admitted to a hospital in the Southern United States (IRR, 1.09; CI, 1.05-1.14) had longer LOS.

CONCLUSIONS

Socioeconomic factors such as race, insurance status, and alcohol use disorder were associated with a prolonged LOS after surgical management of traumatic spine fracture with spinal cord injury.

Radiographic analysis of neuroforaminal and central canal decompression following lateral lumbar interbody fusion

Background

Lateral lumbar interbody fusion (LLIF) is a minimally invasive surgical option for treating symptomatic degenerative lumbar spinal stenosis (DLSS) in select patients. However, the efficacy of LLIF for indirectly decompressing the lumbar spine in DLSS, as well as the best radiographic metrics for evaluating such changes, are incompletely understood.

Methods

A single-institutional cohort of patients who underwent LLIF for DLSS between 5/2015 – 12/2019 was retrospectively reviewed. Diameter, area, and stenosis grades were measured for the central canal (CC) and neural foramina (NF) at each LLIF level based on preoperative and postoperative T2-weighted MRI. Baseline facet joint (FJ) space, degree of FJ osteoarthritis, presence of spondylolisthesis, interbody graft position, and posterior disc height were analyzed as potential predictors of radiographic outcomes. Changes to all metrics after LLIF were analyzed and compared across lumbar levels. Preoperative and intraoperative predictors of decompression were then assessed using multivariate linear regression.

Results

A total of 102 patients comprising 153 fused levels were analyzed. Pairwise linear regression of stenosis grade to diameter and area revealed significant correlations for both the CC and NF. All metrics except CC area were significantly improved after LLIF (p < 0.05, 2-tailed t-test). Worse FJ osteoarthritis ipsilateral to the surgical approach was predictive of greater post-operative CC and NF stenosis grade (p < 0.05, univariate and multivariate ordinary least squares linear regression). Lumbar levels L3-5 had significantly higher absolute postoperative CC stenosis grades while relative change in CC stenosis at the L2-3 was significantly greater than other lumbar levels (p < 0.05, one-way ANOVA). There were no baseline or postoperative differences in NF stenosis grade across lumbar levels.

Conclusions

Radiographically, LLIF is effective at indirect compression of the CC and NF at all lumbar levels, though worse FJ osteoarthritis predicted higher degrees of post-operative stenosis.

Influence of Time of Discharge and Length of Stay on 30-Day Outcomes After Elective Anterior Cervical Spine Surgery

BACKGROUND

Encouraging early time of discharge (TOD) for medical inpatients is commonplace and may potentially improve patient throughput. It is unclear, however, whether early TOD after elective spine surgery achieves this goal without a consequent increase in re-presentations to the hospital.

OBJECTIVE

To evaluate whether early TOD results in increased rates of hospital readmission or return to the emergency department after elective anterior cervical spine surgery.

METHODS

We analyzed 686 patients who underwent elective uncomplicated anterior cervical spine surgery at a single institution. Logistic regression was used to evaluate the relationship between sociodemographic, procedural, and discharge characteristics, and the outcomes of readmission or return to the emergency department and TOD.

RESULTS

In multiple logistic regression, TOD was not associated with increased risk of readmission or return to the emergency department within 30 days of surgery. Weekend discharge (odds ratio [OR] 0.33, 95% CI 0.21-0.53), physical therapy evaluation (OR 0.44, 95% CI 0.28-0.71), and occupational therapy evaluation (OR 0.32, 95% CI 0.17-0.63) were all significantly associated with decreased odds of discharge before noon. Disadvantaged status, as measured by area of deprivation index, was associated with increased odds of readmission or re-presentation (OR 1.86, 95% CI 0.95-3.66), although this result did not achieve statistical significance.

CONCLUSION

There does not appear to be an association between readmission or return to the emergency department and early TOD after elective spine surgery. Overuse of inpatient physical and occupational therapy consultations may contribute to decreased patient throughput in surgical admissions.

Pedicle Screw Placement Using Intraoperative Computed Tomography and Computer-Aided Spinal Navigation Improves Screw Accuracy and Avoids Postoperative Revisions: Single-Center Analysis of 1400 Pedicle Screws

OBJECTIVE

Intraoperative computed tomography and navigation (iCT-Nav) is increasingly used to aid spinal instrumentation. We aimed to document the accuracy and revision rate of pedicle screw placement across many screws placed using iCT-Nav. We also assess patient-level factors predictive of high-grade pedicle breach.

METHODS

Medical records of patients who underwent iCT-Nav pedicle screw placement between 2015 and 2017 at a single center were retrospectively reviewed. Screw placement accuracy was individually assessed for each screw using the 2-mm incremental grading system for pedicle breach. Predictors of high-grade (>2 mm) breach were identified using multiple logistic regression.

RESULTS

In total, 1400 pedicle screws were placed in 208 patients undergoing cervicothoracic (29; 13.9%), thoracic (30; 14.4), thoracolumbar (19; 9.1%) and lumbar (130; 62.5%) surgeries. iCT-Nav afforded high-accuracy screw placement, with 1356 of 1400 screws (96.9%) being placed accurately. In total, 37 pedicle screws (2.64%) were revised intraoperatively during the index surgery across 31 patients, with no subsequent returns to the operating room because of screw malpositioning. After correcting for potential confounders, males were less likely to have a high-grade breach (odds ratio [OR] 0.21; 95% confidence interval [CI] 0.10-0.59, P = 0.003) whereas lateral (OR 6.21; 95% CI 2.47-15.52, P < 0.001) or anterior (OR 5.79; 95% CI2.11-15.88, P = 0.001) breach location were predictive of a high-grade breach.

CONCLUSIONS

iCT-Nav with postinstrumentation intraoperative imaging is associated with a reduced need for costly postoperative return to the operating room for screw revision. In comparison with studies of navigation without iCT where 1.5%-1.7% of patients returned for a second surgery, we report 0 revision surgeries due to screw malpositioning.

Influence of psychosocial and sociodemographic factors in the surgical management of traumatic cervicothoracic spinal cord injury at level I and II trauma centers in the United States

Background

Socioeconomic factors can bias clinician decision-making in many areas of medicine. Psychosocial characteristics such as diagnosis of alcoholism, substance abuse, and major psychiatric disorder are emerging as potential sources of conscious and unconscious bias. We hypothesized that these psychosocial factors, in addition to socioeconomic factors, may impact the decision to operate on patients with a traumatic cervicothoracic fracture and associated spinal cord injury (SCI).

Methods

We performed a cohort analysis using clinical data from 2012-2016 in the American College of Surgeons (ACS) National Trauma Data Bank at academic level I and II trauma centers. Patients were eligible if they had a diagnosis of cervicothoracic fracture with SCI. Using ICD codes, we evaluated baseline characteristics including race; insurance status; diagnosis of alcoholism, substance abuse, or major psychiatric disorder; admission drug screen and blood alcohol level; injury characteristics and severity; and hospital characteristics including geographic region, non-profit status, university affiliation, and trauma level. Factors significantly associated with surgical intervention in univariate analysis were eligible for inclusion in multivariate logistic regression.

Results

We identified 6,655 eligible patients, of whom 62% underwent surgical treatment (n=4,137). Patients treated non-operatively were more likely to be older; be female; be Black or Hispanic; have Medicare, Medicaid, or no insurance; have been assaulted; have been injured by a firearm; have thoracic fracture; have less severe injuries; have severe TBI; be treated at non-profit hospitals; and be in the Northeast or Western U.S. (all P<0.01). After adjusting for confounders in multivariate analysis, only insurance status remained associated with operative treatment. Medicaid patients (OR=0.81; P=0.021) and uninsured patients (OR=0.63; P<0.001) had lower odds of surgery relative to patients with private insurance. Injury severity and facility characteristics also remained significantly associated with surgical management following multivariate regression.

Conclusions

Psychosocial characteristics such as diagnosis of alcoholism, substance abuse, or psychiatric illness do not appear to bias the decision to operate after traumatic cervicothoracic fracture with SCI. Baseline sociodemographic imbalances were explained largely by insurance status, injury, and facility characteristics in multivariate analysis.

Supplementation of Screw-Rod C1-C2 Fixation With Posterior Arch Femoral Head Allograft Strut

BACKGROUND

Numerous C1-C2 fixation techniques exist for the treatment of atlantoaxial instability. Limitations of screw-rod and sublaminar wiring techniques include C2 nerve root sacrifice and dural injury, respectively. We present a novel technique that utilizes a femoral head allograft cut with a keyhole that rests posteriorly on the arches of C1 and C2 and straddles the C2 spinous process, secured by sutures.

OBJECTIVE

To offer increased fusion across C1-C2 without the passage of sublaminar wiring or interarticular arthrodesis.

METHODS

A total of 6 patients with atlantoaxial instability underwent C1-C2 fixation using our method from 2015 to 2016. After placement of a C1-C2 screw/rod construct, a cadaveric frozen femoral head allograft was cut into a half-dome with a keyhole and placed over the already decorticated dorsal C1 arch and C2 spinous process. Notches were created in the graft and sutures were placed in the notches and around the rods to secure it firmly in place.

RESULTS

The femoral head's shape allowed for creation of a graft that provides excellent surface area for fusion across C1-C2. There were no intraoperative complications, including dural tears. Postoperatively, no patients had sensorimotor deficits, pain, or occipital neuralgia. 5 patients demonstrated clinical resolution of symptoms by 3 mo and radiographic (computed tomography) evidence of fusion at 1 yr. One patient had good follow-up at 1 mo but died due to complications of Alzheimer disease.

CONCLUSION

The posterior arch femoral head allograft strut technique with securing sutures is a viable option for supplementing screw-rod fixation in the treatment of complex atlantoaxial instability.

Existing clinical evidence on the use of cellular bone matrix grafts in spinal fusion: updated systematic review of the literature

OBJECTIVE

Spinal fusion surgery is increasingly common; however, pseudarthrosis remains a common complication affecting as much as 15% of some patient populations. Currently, no clear consensus on the best bone graft materials to use exists. Recent advances have led to the development of cell-infused cellular bone matrices (CBMs), which contain living components such as mesenchymal stem cells (MSCs). Relatively few clinical outcome studies on the use of these grafts exist, although the number of such studies has increased in the last 5 years. In this study, the authors aimed to summarize and critically evaluate the existing clinical evidence on commercially available CBMs in spinal fusion and reported clinical outcomes.

METHODS

The authors performed a systematic search of the MEDLINE and PubMed electronic databases for peer-reviewed, English-language original articles (1970-2020) in which the articles' authors studied the clinical outcomes of CBMs in spinal fusion. The US National Library of Medicine electronic clinical trials database (www.ClinicalTrials.gov) was also searched for relevant ongoing clinical trials.

RESULTS

Twelve published studies of 6 different CBM products met inclusion criteria: 5 studies of Osteocel Plus/Osteocel (n = 354 unique patients), 3 of Trinity Evolution (n = 114), 2 of ViviGen (n = 171), 1 of map3 (n = 41), and 1 of VIA Graft (n = 75). All studies reported high radiographic fusion success rates (range 87%-100%) using these CBMs. However, this literature was overwhelmingly limited to single-center, noncomparative studies. Seven studies disclosed industry funding or conflicts of interest (COIs). There are 4 known trials of ViviGen (3 trials) and Bio4 (1 trial) that are ongoing.

CONCLUSIONS

CBMs are a promising technology with the potential of improving outcome after spinal fusion. However, while the number of studies conducted in humans has tripled since 2014, there is still insufficient evidence in the literature to recommend for or against CBMs relative to cheaper alternative materials. Comparative, multicenter trials and outcome registries free from industry COIs are indicated.

A transpedicular approach to complex ventrally situated thoracic intradural extramedullary tumors: technique, indications, and multiinstitutional case series

OBJECTIVE

Ventrally situated thoracic intradural extramedullary tumors are surgically challenging and difficult to access, and they may be complicated by extensive adhesions and calcifications. Selecting an approach for adequate ventral access is key to complete resection and optimization of outcomes. The authors present a case series of patients who underwent resection of ventral thoracic intradural extramedullary tumors and discuss indications and considerations for this technique. Additionally, they describe the use of a posterolateral transpedicular approach for resection of ventral thoracic intradural extramedullary tumors compared with other techniques, and they summarize the literature supporting its application.

METHODS

From May 2017 to August 2020, 5 patients with ventral thoracic intradural extramedullary tumors underwent resection at one of the two academic institutions.

RESULTS

Patient ages ranged from 47 to 75 (mean 63.4) years. All tumors were diagnosed as meningiomas or schwannomas by histological examination. Three of the 5 patients had evidence of partial or extensive tumor calcification. Four of the 5 patients underwent an initial posterolateral transpedicular approach for resection, with positive radiographic and clinical outcomes from surgery. One patient initially underwent an unsuccessful traditional direct posterior approach and required additional resection 2 years later after interval disease progression. There were no postoperative wound infections, CSF leaks, or other complications related to the transpedicular approach.

CONCLUSIONS

Posterolateral transpedicular tumor resection is a safe technique for the treatment of complex ventrally situated thoracic intradural extramedullary tumors compared with the direct posterior approach. Anecdotally, this approach appears to be particularly beneficial in patients with calcified tumors.

Chordoma-Current Understanding and Modern Treatment Paradigms

Chordoma is a low-grade notochordal tumor of the skull base, mobile spine and sacrum which behaves malignantly and confers a poor prognosis despite indolent growth patterns. These tumors often present late in the disease course, tend to encapsulate adjacent neurovascular anatomy, seed resection cavities, recur locally and respond poorly to radiotherapy and conventional chemotherapy, all of which make chordomas challenging to treat. Extent of surgical resection and adequacy of surgical margins are the most important prognostic factors and thus patients with chordoma should be cared for by a highly experienced, multi-disciplinary surgical team in a quaternary center. Ongoing research into the molecular pathophysiology of chordoma has led to the discovery of several pathways that may serve as potential targets for molecular therapy, including a multitude of receptor tyrosine kinases (e.g., platelet-derived growth factor receptor [PDGFR], epidermal growth factor receptor [EGFR]), downstream cascades (e.g., phosphoinositide 3-kinase [PI3K]/protein kinase B [Akt]/mechanistic target of rapamycin [mTOR]), brachyury—a transcription factor expressed ubiquitously in chordoma but not in other tissues—and the fibroblast growth factor [FGF]/mitogen-activated protein kinase kinase [MEK]/extracellular signal-regulated kinase [ERK] pathway. In this review article, the pathophysiology, diagnosis and modern treatment paradigms of chordoma will be discussed with an emphasis on the ongoing research and advances in the field that may lead to improved outcomes for patients with this challenging disease.

A minimally invasive lateral approach with CT navigation for open biopsy and diagnosis of Nocardia nova L4–5 discitis osteomyelitis: illustrative case

BACKGROUND

Lumbar spine osteomyelitis can be refractory to conventional techniques for identifying a causal organism. In cases in which a protracted antibiotic regimen is indicated, obtaining a conclusive yield on biopsy is particularly important. Although lateral transpsoas approaches and intraoperative computed tomography (CT) navigation are well documented as techniques used for spinal arthrodesis, their utility in vertebral biopsy has yet to be reported in any capacity.

OBSERVATIONS

In a 44-year-old male patient with a history of Nocardia bacteremia, CT-guided biopsy failed to confirm the microbiology of an L4–5 discitis osteomyelitis. The patient underwent a minimally invasive open biopsy in which a lateral approach with intraoperative guidance was used to access the infected disc space retroperitoneally. A thin film was obtained and cultured Nocardia nova, and the patient was treated accordingly with a long course of trimethoprim-sulfamethoxazole.

LESSONS

The combination of a lateral transpsoas approach with intraoperative navigation is a valuable technique for obtaining positive yield in cases of discitis osteomyelitis of the lumbar spine refractory to CT-guided biopsy.

A modern multidisciplinary approach to a large cervicothoracic chordoma using staged en bloc resection with intraoperative image-guided navigation and 3D-printed modeling: illustrative case

BACKGROUND

Cervicothoracic junction chordomas are uncommon primary spinal tumors optimally treated with en bloc resection. Although en bloc resection is the gold standard for treatment of mobile spinal chordoma, tumor location, size, and extent of involvement frequently complicate the achievement of negative margins. In particular, chordoma involving the thoracic region can require a challenging anterior access, and en bloc resection can lead to a highly destabilized spine.

OBSERVATIONS

Modern technological advances make en bloc resection more technically feasible than ever before. In this case, the successful en bloc resection of a particularly complex cervicothoracic junction chordoma was facilitated by a multidisciplinary surgical approach that maximized the use of intraoperative computed tomography–guided spinal navigation and patient-specific three-dimensional–printed modeling.

LESSONS

The authors review the surgical planning and specific techniques that facilitated the successful en bloc resection of this right-sided chordoma via image-guided parasagittal osteotomy across 2 stages. The integration of emerging visualization technologies into complex spinal column tumor management may help to provide optimal oncological care for patients with challenging primary tumors of the mobile spine.

A Novel Endoscopic Technique for Biopsy and Tissue Diagnosis for a Paraspinal Thoracic Tumor in a Pediatric Patient: A Case Report

BACKGROUND

Conventional approaches to the thoracic spine can require extensive tissue dissection, bony disruption, and instability that may warrant the need for instrumentation and fusion. Furthermore, anterior approaches may require the involvement of various surgeons from multiple disciplines to ensure a successful operation and mitigate complications. Currently, available minimally invasive approaches still require bony removal and usually rely heavily on computed tomography (CT)-guided imaging without direct gross visualization. Endoscopic spinal procedures have provided an ultra-minimally invasive alternative to access many areas in and around the spinal column.

METHODS

We present a 12-year-old boy with a right-sided 2.0 × 3.2-cm paravertebral lesion at the level of T5. The patient successfully underwent an endoscopic approach to the lesion with minimal tissue and bony disruption for tissue diagnosis and tumor resection.

RESULTS

At initial and 6-month follow-up, the patient remained asymptomatic and without issues.

CONCLUSIONS

We demonstrate here the feasibility and suggest the safety of a posterior ultra-minimally invasive endoscopic spinal approach to obtain a tissue biopsy of an incidentally found ventrolateral paraspinal tumor in the thoracic region in a pediatric patient. This minimal approach can prove to achieve similar results as other approaches that may otherwise necessitate more extensive or transthoracic procedures.

Three-Dimensional Printed Anatomic Modeling for Surgical Planning and Real-Time Operative Guidance in Complex Primary Spinal Column Tumors: Single-Center Experience and Case Series

OBJECTIVE

Three-dimensional (3D) printing has emerged as a visualization tool for clinicians and patients. We sought to use patient-specific 3D-printed anatomic modeling for preoperative planning and live intraoperative guidance in a series of complex primary spine tumors.

METHODS

Over 9 months, patients referred to a single neurosurgical provider for complex primary spinal column tumors were included. Most recent spinal magnetic resonance and computed tomography (CT) imaging were semiautomatically segmented for relevant anatomy and models were printed using polyjet multicolor printing technology. Models were available to surgical teams before and during the operative procedure. Patients also viewed the models preoperatively during surgeon explanation of disease and surgical plan to aid in their understanding.

RESULTS

Tumor models were prepared for 9 patients, including 4 with chordomas, 2 with schwannomas, 1 with osteosarcoma, 1 with chondrosarcoma, and 1 with Ewing-like sarcoma. Mean age was 50.7 years (range, 15-82 years), including 6 males and 3 females. Mean tumor volume was 129.6 cm³ (range, 3.3-250.0 cm³). Lesions were located at cervical, thoracic, and sacral levels and were treated by various surgical approaches. Models were intraoperatively used as patient-specific anatomic references throughout 7 cases and were found to be technically useful by the surgical teams.

CONCLUSIONS

We present the largest case series of 3D-printed spine tumor models reported to date. 3D-printed models are broadly useful for operative planning and intraoperative guidance in spinal oncology surgery.

Traumatic unilateral jumped facet joint in the upper thoracic spine: Case presentation and literature review

Background:

A jumped facet joint is defined by when the inferior articular process of the superior vertebra becomes locked anterior to the superior articular process of the inferior vertebra. These typically traumatic lesions are exceedingly rare in the thoracic spine. Here, we present a patient with a unilateral jumped facet joint in the upper thoracic spine treated with open reduction and an instrumented fusion.

Case Description:

A 45-year-old male presented after a significant motor vehicle accident. In the emergency room, he had a Glasgow Coma Score of 13 without any neurologic deficit. The thoracic computed tomography (CT) showed a significant jumped left facet at the T2-T3 level. Two days later, utilizing intraoperative CT-guided navigation and neuromonitoring, he underwent open reduction of the T2-T3 jumped facet plus an instrumented T1-T5 fusion. X-rays taken 3-month postoperatively showed a stable construct. Six months postoperatively, he remained neurologically intact.

Conclusion:

A unilateral jumped thoracic facet may be present in patients with fractured ribs. The mechanism of injury is most likely axial rotation. Both CT and magnetic resonance imaging studies allow for early detection of these very rare lesions and warrant open reduction and instrumented fusion.

Complex wound closure by plastic surgery following resection of spinal neoplasms minimizes postoperative wound complications in high-risk patients

OBJECTIVE

Wound breakdown and infection are common postoperative complications following resection of spinal neoplasms. Accordingly, it has become common practice at some centers for plastic surgeons to assist with closure of large posterior defects after spine tumor resection. In this study, the authors tested the hypothesis that plastic surgery closure of complex spinal defects improves wound outcomes following resection of spinal neoplastic disease.

METHODS

Electronic medical records of consecutive patients who underwent resection of a spinal neoplasm between June 2015 and January 2019 were retrospectively reviewed. Patients were separated into two subpopulations based on whether the surgical wound was closed by plastic surgery or neurosurgery. Patient demographics, preoperative risk factors, surgical details, and postoperative outcomes were collected in a central database and summarized using descriptive statistics. Outcomes of interest included rates of wound complication, reoperation, and mortality. Known preoperative risk factors for wound complication in spinal oncology were identified based on literature review and grouped categorically. The presence of each category of risk factors was then compared between groups. Univariate and multivariate linear regressions were applied to define associations between individual risk factors and wound complications.

RESULTS

One hundred six patients met inclusion criteria, including 60 wounds primarily closed by plastic surgery and 46 by neurosurgery. The plastic surgery population included more patients with systemic metastases (58% vs 37%, p = 0.029), prior radiation (53% vs 17%, p < 0.001), prior chemotherapy (37% vs 15%, p = 0.014), and sacral region tumors (25% vs 7%, p = 0.012), and more patients who underwent procedures requiring larger incisions (7.2 ± 3.6 vs 4.5 ± 2.6 levels, p < 0.001), prolonged operative time (413 ± 161 vs 301 ± 181 minutes, p = 0.001), and greater blood loss (906 ± 1106 vs 283 ± 373 ml, p < 0.001). The average number of risk factor categories present was significantly greater in the plastic surgery group (2.57 vs 1.74, p < 0.001). Despite the higher relative risk, the plastic surgery group did not experience a significantly higher rate of wound complication (28% vs 17%, p = 0.145), reoperation (17% vs 9%, p = 0.234), or all-cause mortality (30% vs 13%, p = 0.076). One patient died from wound-related complications in each group (p = 0.851). Regression analyses identified diabetes, multilevel instrumentation, and BMI as the factors associated with the greatest wound complications.

CONCLUSIONS

Involving plastic surgery in the closure of spinal wounds after resection of neoplasms may ameliorate expected increases in wound complications among higher-risk patients.

Objective Indirect Assessment of Transverse Ligament Competence Using Quantitative Analysis of 3-Dimensional Segmented Flexion-Extension Computed Tomography Scan

OBJECTIVE

Assessment of transverse ligament (TL) competence in patients with suspected atlantoaxial instability is performed via indirect radiograph measurements or direct TL visualization on magnetic resonance imaging (MRI). Interpretation of these images can be limited by unique patient anatomy or imaging technique variability. We report a novel technique for evaluating TL competence using flexion-extension computed tomography (feCT) scan with 3-dimensional (3D) segmentation and quantitative analysis.

METHODS

feCT scans of 11 patients were segmented to create 3D surface models. Six patients with atlantoaxial pathology were evaluated for possible instability based on clinical examination and imaging findings. The other 5 patients had no clinical or imaging evidence of atlantoaxial injury. Dynamic atlantodental interval (ADI) was calculated using point-to-point voxel changes between flexion and extension 3D models. Magnitude and direction of ADI changes were quantified and compared with available cervical spine flexion-extension radiograph and/or MRI findings.

RESULTS

In the 5 patients without evidence of atlantoaxial injury, 94.3% of ADI vector changes were <3.0 mm. In the 3 patients with atlantoaxial pathology but TL competence, 92.4% of ADI vector changes were <3.0 mm. In the 3 patients with atlantoaxial pathology and TL incompetence, only 49.1% of ADI vector changes were <3.0 mm. In addition to the significant atlantoaxial subluxation in these 3 patients, there was significant rotational motion compared with the patients with an intact TL.

CONCLUSIONS

3D segmentation and quantitative analysis of feCT scan allow objective indirect assessment of TL integrity. Results are consistent with MRI findings and offer additional biomechanical information regarding the direction and distribution of atlantoaxial motion.

Oncologic benefits of dural resection in spinal meningiomas: a meta-analysis of Simpson grades and recurrence rates

OBJECTIVE

While resection of the dural attachment has been shown by Simpson and others to reduce recurrence rates for intracranial meningiomas, the oncological benefit of dural resection for spinal meningiomas is less clear. The authors performed a systematic analysis of the literature, comparing recurrence rates for patients undergoing various Simpson grade resections of spinal meningiomas to better understand the role of dural resection on outcomes after resection of spinal meningiomas.

METHODS

The PubMed/Medline database was systematically searched to identify studies describing oncological and clinical outcomes after Simpson grade I, II, III, or IV resections of spinal meningiomas.

RESULTS

Thirty-two studies describing the outcomes of 896 patients were included in the analysis. Simpson grade I, grade II, and grade III/IV resections were performed in 27.5%, 64.6%, and 7.9% of cases, respectively. The risk of procedure-related complications (OR 4.75, 95% CI 1.27-17.8, p = 0.021) and new, unexpected postoperative neurological deficits (OR ∞, 95% CI NaN-∞, p = 0.009) were both significantly greater for patients undergoing Simpson grade I resections when compared with those undergoing Simpson grade II resections. Tumor recurrence was seen in 2.8%, 4.1%, and 39.4% of patients undergoing Simpson grade I, grade II, and grade III/IV resections over a mean radiographic follow-up period of 99.3 ± 46.4 months, 95.4 ± 57.1 months, and 82.4 ± 49.3 months, respectively. No significant difference was detected between the recurrence rates for Simpson grade I versus Simpson grade II resections (OR 1.43, 95% CI 0.61-3.39, p = 0.43). A meta-analysis of 7 studies directly comparing recurrence rates for Simpson grade I and II resections demonstrated a trend toward a decreased likelihood of recurrence after Simpson grade I resection when compared with Simpson grade II resection, although this trend did not reach statistical significance (OR 0.56, 95% CI 0.23-1.36, p = 0.20).

CONCLUSIONS

The results of this analysis suggest with a low level of confidence that the rates of complications and new, unexpected neurological deficits after Simpson grade I resection of spinal meningiomas are greater than those seen with Simpson grade II resections, and that the recurrence rates for Simpson grade I and grade II resections are equivalent, although additional, long-term studies are needed before reliable conclusions may be drawn.

Spinal dural resection for oncological purposes: a systematic analysis of risks and outcomes in patients with malignant spinal tumors

OBJECTIVE

Oncological outcomes for many malignant primary spinal tumors and isolated spinal metastases have been shown to correlate with extent of resection. For tumors with dural involvement, some authors have described spinal dural resection at the time of tumor resection in the interest of improving oncological outcomes. The complication profile associated with resection of the spinal dura for oncological purposes, however, and the relative influence of resecting tumor-involved dura on progression-free survival are not well defined. The authors performed a systematic review of the literature and identified cases in which the spinal dura was resected for oncological purposes in the interest of better understanding the associated risks and outcomes of this technique.

METHODS

Electronic databases (PubMed/MEDLINE, Scopus) were systematically searched to identify studies that reported clinical and/or oncological outcomes of patients with malignant spinal neoplasms undergoing resection of tumor-involved dura at the time of surgical intervention.

RESULTS

Ten articles describing 15 patients were included in the analysis. The most common tumor histologies were chordoma (3/15, 20%), giant cell tumor (3/15, 20%), epithelioid sarcoma (2/15, 13.3%), osteosarcoma (2/15, 13.3%), and metastasis (2/15, 13.3%). Procedure-related complications were reported in 40% of patients. A trend was seen toward an increased complication rate in redo (66.7%) versus index (16.7%) operations, but this trend did not reach statistical significance (p = 0.24). New, unexpected postoperative neurological deficits were seen in 3 patients (of 14 reporting, 21.4%). A single patient experienced a profound, unexpected neurological deterioration (paraparesis/paraplegia) after surgery, which reportedly improved considerably at latest follow-up. Tumor recurrence was seen in 3 cases (of 12 reporting, 25%) at a mean of 28.34 ± 21.1 months postoperatively. The overall mean radiographic follow-up period was 49.6 ± 36.5 months.

CONCLUSIONS

Resection of the spinal dura for oncological purposes is rarely performed, although a limited number of reports and small series have demonstrated that it is feasible. Spinal dural resection is primarily performed in patients with isolated, primary spinal neoplasms with an intent to cure. The risk associated with spinal dura resection is nontrivial and the complication profile is significant. The influence of dural resection on oncological outcomes is not well defined, and further study is needed before definitive conclusions may be drawn regarding the oncological benefit of dural resection for any particular patient or pathology.

Outcomes of endoscopic discectomy compared with open microdiscectomy and tubular microdiscectomy for lumbar disc herniations: a meta-analysis

OBJECTIVE

Endoscopic discectomy (ED) has been advocated as a less-invasive alternative to open microdiscectomy (OM) and tubular microdiscectomy (TM) for lumbar disc herniations, with the potential to decrease postoperative pain and shorten recovery times. Large-scale, objective comparisons of outcomes between ED, OM, and TM, however, are lacking. The authors' objective in this study was to conduct a meta-analysis comparing outcomes of ED, OM, and TM.

METHODS

The PubMed database was searched for articles published as of February 1, 2019, for comparative studies reporting outcomes of some combination of ED, OM, and TM. A meta-analysis of outcome parameters was performed assuming random effects.

RESULTS

Twenty-six studies describing the outcomes of 2577 patients were included. Estimated blood loss was significantly higher with OM than with both TM (p = 0.01) and ED (p < 0.00001). Length of stay was significantly longer with OM than with ED (p < 0.00001). Return to work time was significantly longer in OM than with ED (p = 0.001). Postoperative leg (p = 0.02) and back (p = 0.01) VAS scores, and Oswestry Disability Index scores (p = 0.006) at latest follow-up were significantly higher for OM than for ED. Serum creatine phosphokinase (p = 0.02) and C-reactive protein (p < 0.00001) levels on postoperative day 1 were significantly higher with OM than with ED.

CONCLUSIONS

Outcomes of TM and OM for lumbar disc herniations are largely equivalent. While this analysis demonstrated that several clinical variables were significantly improved in patients undergoing ED when compared with OM, the magnitude of many of these differences was small and of uncertain clinical relevance, and several of the included studies were retrospective and subject to a high risk of bias. Further high-quality prospective studies are needed before definitive conclusions can be drawn regarding the comparative efficacy of the various surgical treatments for lumbar disc herniations.

Minimally invasive approach to non-missile penetrating spinal injury with resultant retained foreign body: A case report and review of the literature

Non- missile penetrating spinal injury (NMPSI) is a rare entity in North America and as a result there is no clear treatment paradigm. According to the literature, NMPSI causes serious acute neurological deficits and can also lead to devastating delayed complications in cases of untreated retained foreign bodies (RFB). In this report we present an acute case of NMPSI to the thoracic spine resulting in RFB treated by operative removal using minimally invasive fluoroscopic technique. While in prior published cases of NMPSI operative intervention was accomplished through laminectomy, our case presents an alternative, less invasive approach which may results in shorter recovery time. We also review the literature on NMPSI, including reports on both acute cases and chronic presentation due to RFBs. Based on this review, we conclude that NMPSI associated with RFB should be managed with operative intervention.

Cerebrospinal fluid leaks after spine tumor resection: avoidance, recognition and management

Post-operative CSF leaks are a known complication of spine surgery in general, and patients undergoing surgical intervention for spinal tumors may be particularly predisposed due to the presence of intradural tumor and a number of other factors. Post-operative CSF leaks increase morbidity, lengthen hospital stays, prolong immobilization and subject patients to a number of associated complications. Intraoperative identification of unintended durotomies and effective primary repair of dural defects is an important first step in the prevention of post-operative CSF leaks, but in patients who develop post-operative pseudomeningoceles, durocutaneous fistulae or other CSF-leak-related sequelae, early recognition and secondary intervention are paramount to preventing further CSF-leak-related complications and achieving the best patient outcomes possible. In this article, the incidence, risk factors and complications of CSF leaks after spine tumor surgery are reviewed, with an emphasis on avoidance of post-operative CSF leaks, early post-operative identification and effective secondary intervention.

Maximizing Sacral Chordoma Resection by Precise 3-Dimensional Tumor Modeling in the Operating Room Using Intraoperative Computed Tomography Registration with Preoperative Magnetic Resonance Imaging Fusion and Intraoperative Neuronavigation: A Case Series

INTRODUCTION

The primary treatment for patients with sacral chordoma is en bloc surgical resection with negative margins, which has been shown to reduce local recurrence and tumor-related morbidity. Here we describe the use of intraoperative neuronavigation using preoperative spine magnetic resonance imaging fused to intraoperative computed tomography (CT) to create 3-dimensional tumor reconstructions in the operating room for intraoperative identification of bone and soft-tissue margins for maximal safe tumor resection.

METHODS

A single-institution retrospective chart review was completed to encompass our experience of 6 consecutive patients who had sacral chordoma resections using our described navigation protocol. We collected data on patient demographics, previous surgeries, radiation therapy, preoperative examination, spinal levels involved, dural involvement, estimated blood loss, surgery time, tissue diagnosis, follow-up, postoperative examination, complications, and recurrence. Primary outcome was en bloc resection with negative margins as planned preoperatively.

RESULTS

Negative surgical margins were achieved in 5 of 5 patients, who were preoperatively planned for en bloc resection with negative margins. The most common levels involved were S4-S5. All patients had a stable or improved neurologic examination after en bloc surgical resection. The average follow-up was 5.4 months ± 84.6 days. No patient had residual or recurrent tumor at last follow-up.

CONCLUSIONS

Magnetic resonance imaging-CT fusion and 3-dimensional reconstruction techniques using an intraoperative CT scanner with image-guided navigation to aid preoperative planning and surgical resection of sacral chordomas are not well represented in the literature. This technique can be used for planning en bloc surgical resections and for more precisely identifying tumor margins intraoperatively.

Minimally invasive direct lateral, retroperitoneal transforaminal approach for large L1-2 disc herniations with intraoperative CT navigational assistance: technical note and report of 3 cases

Upper lumbar (L1-2, L2-3) disc herniations are distinct in their diffuse presenting clinical symptomatology and have poorer outcomes with surgical intervention than those following mid and lower lumbar disc herniations and disc surgery. The authors present the cases of 3 patients with L1-2 disc herniations and significant stenosis of the spinal canal. The surgical approach used here combined the principles of transforaminal percutaneous endoscopic discectomy and the extreme lateral lumbar interbody fusion procedures with intraoperative CT-guided navigational assistance. The approach provides a safe corridor of direct visualization to the ventral thecal sac with minimal bony resection and could, in principle, reduce neurological injury and biomechanical instability, which likely contribute to poor outcomes at this level.

Rhode Island Hospital's Contribution to the Field of Endoscopic Spine Surgery

The first academic program in endoscopic spine surgery in the United States opened its doors at Rhode Island Hospital in 2012. Published advances in the field since its inception have included treatments for a myriad of pathologies including lumbar and thoracic disc herniations, spondylolisthesis, spine tumors as well as treatments for complications of other spinal procedures including spinal fusion, kyphoplasty, and total disc replacement. In this issue of the Rhode Island Medical Journal we summarize the history of the procedure as well as some of the interesting progress going on in this field in Rhode Island. [Full article available at http://rimed.org/rimedicaljournal-2017-06.asp].

Current Treatment of Metastatic Spine Tumors - Surgery and Stereotactic Radiosurgery

There has been significant progress and innovation in the treatment of patients with metastatic spinal tumors over the last two to three decades that has impacted our ability to provide individualized care that improves a patient's quality of life and degree of neurologic impairment. Advances in surgical techniques and radiation delivery modalities have dramatically improved our ability to decrease local tumor recurrence rates, improve pain control, and provide more durable spinal stability. Modern day spine tumor resection and reconstruction techniques have been shown to improve and prolong patients' ability to ambulate, maintain continence, and reduce the need for pain medications. Spinal radiosurgery, the focused delivery of radiation to a target in the spine, has significantly enhanced the ability to provide a high degree of local tumor control in a non-invasive manner, even for tumors that are deemed radioresistant by conventional radiation therapy standards. In most patients, a combination of treatment modalities, including both surgery and radiation, is the mainstay of any comprehensive treatment plan for metastatic spinal tumors. [Full article available at http://rimed.org/rimedicaljournal-2017-06.asp].

A brief history of endoscopic spine surgery

Few neurosurgeons practicing today have had training in the field of endoscopic spine surgery during residency or fellowship. Nevertheless, over the past 40 years individual spine surgeons from around the world have worked to create a subfield of minimally invasive spine surgery that takes the point of visualization away from the surgeon's eye or the lens of a microscope and puts it directly at the point of spine pathology. What follows is an attempt to describe the story of how endoscopic spine surgery developed and to credit some of those who have been the biggest contributors to its development.

Technical considerations in transforaminal endoscopic spine surgery at the thoracolumbar junction: report of 3 cases

OBJECTIVE In this study the authors describe the technical considerations and feasibility of transforaminal discectomy and foraminoplasty for the treatment of lumbar radiculopathy in patients who have herniated discs at the thoracolumbar junction. METHODS After institutional review board approval, charts from 3 consecutive patients with lumbar radiculopathy and T12-L1 herniated discs who underwent endoscopic procedures between 2006 and 2014 were reviewed. RESULTS Consecutive cases (n = 1316) were reviewed to determine the incidence and success of surgery performed at the T12-L1 level. Only 3 patients (0.23%) treated with endoscopic surgery for their herniated discs had T12-L1 herniated discs; the rest were lumbar or lumbosacral herniations. For patients with T12-L1 disc herniations, the average preoperative visual analog scale score was 8.3 (indicated in the questionnaire as describing severe and constant pain). The average 1-year postoperative visual analog scale score was 1.7 (indicated in the questionnaire as mild and intermittent pain). CONCLUSIONS Transforaminal endoscopic discectomy and foraminotomy can be used as a safe yet minimally invasive technique for the treatment of lumbar radiculopathy in the setting of a thoracolumbar disc herniation.

Interdisciplinary Management of Minimally Displaced Orbital Roof Fractures: Delayed Pulsatile Exophthalmos and Orbital Encephalocele

Traumatic orbital roof fractures are rare and are managed nonoperatively in most cases. They are typically associated with severe mechanisms of injury and may be associated with significant neurologic or ophthalmologic compromise including traumatic brain injury and vision loss. Rarely, traumatic encephalocele or pulsatile exophthalmos may be present at the time of injury or develop in delayed fashion, necessitating close observation of these patients. In this article, we describe two patients with minimally displaced blow-in type orbital roof fractures that were later complicated by orbital encephalocele and pulsatile exophthalmos, prompting urgent surgical intervention. We also suggest a management algorithm for adult patients with orbital roof fractures, emphasizing careful observation and interdisciplinary management involving plastic surgery, neurosurgery, and ophthalmology.

Self-inflicted nail-gun injury with cranial penetration and use of intraoperative computed tomography

BACKGROUND

Management of penetrating cranial trauma remains a high acuity and imaging intense neurosurgical disorder. Imaging of vital structures, including angiography, is typically conducted to understand the proximity of vital structures in comparison to a foreign body and prepare for intraoperative complications such as hemorrhage. Preservation of function following initial injury in cases where minimal neurological deficit exists is essential.

CASE DESCRIPTION

Here, we present a case using intraoperative computed tomography to assist in early detection and resolution of hemorrhage in the surgical management of an intact patient with self-inflicted penetrating cranial trauma.

CONCLUSIONS

This method may aid in early detection of hemorrhage and prevention of consequential neurological deterioration or emergent need for secondary surgery.