Multidisciplinary surgical considerations for en bloc resection of sacral chordoma: review of recent advances and a contemporary single-center series.

OBJECTIVE: Contemporary management of sacral chordomas requires maximizing the potential for recurrence-free and overall survival while minimizing treatment morbidity. En bloc resection can be performed at various levels of the sacrum, with tumor location and volume ultimately dictating the necessary extent of resection and subsequent tissue reconstruction. Because tumor resection involving the upper sacrum may be quite destabilizing, other pertinent considerations relate to instrumentation and subsequent tissue reconstruction. The primary aim of this study was to survey the surgical approaches used for managing primary sacral chordoma according to location of lumbosacral spine involvement, including a narrative review of the literature and examination of the authors' institutional case series. METHODS: The authors performed a narrative review of pertinent literature regarding reconstruction and complication avoidance techniques following en bloc resection of primary sacral tumors, supplemented by a contemporary series of 11 cases from their cohort. Relevant surgical anatomy, advances in instrumentation and reconstruction techniques, intraoperative imaging and navigation, soft-tissue reconstruction, and wound complication avoidance are also discussed. RESULTS: The review of the literature identified several surgical approaches used for management of primary sacral chordoma localized to low sacral levels (mid-S2 and below), high sacral levels (involving upper S2 and above), and high sacral levels with lumbar involvement. In the contemporary case series, the majority of cases (8/11) presented as low sacral tumors that did not require instrumentation. A minority required more extensive instrumentation and reconstruction, with 2 tumors involving upper S2 and/or S1 levels and 1 tumor extending into the lower lumbar spine. En bloc resection was successfully achieved in 10 of 11 cases, with a colostomy required in 2 cases due to rectal involvement. All 11 cases underwent musculocutaneous flap wound closure by plastic surgery, with none experiencing wound complications requiring revision. CONCLUSIONS: The modern management of sacral chordoma involves a multidisciplinary team of surgeons and intraoperative technologies to minimize surgical morbidity while optimizing oncological outcomes through en bloc resection. Most cases present with lower sacral tumors not requiring instrumentation, but stabilizing instrumentation and lumbosacral reconstruction are often required in upper sacral and lumbosacral cases. Among efforts to minimize wound-related complications, musculocutaneous flap closure stands out as an evidence-based measure that may mitigate risk.

Systematic Review of Prophylactic Plastic Surgery Closure to Prevent Postoperative Wound Complications Following Spine Surgery.

Spinal surgeries are increasingly performed in the United States, but complication rates can be unacceptably high at up to 26%. Consequently, plastic surgeons (PS) are sometimes recruited by spine surgeons (SS) for intraoperative assistance with soft tissue closures. An electronic multidatabase literature search was systematically conducted to determine whether spinal wound closure performed by PS minimizes postoperative wound healing complications when compared to closure by SS (neurosurgical or orthopedic), with the hypothesis that closures by PS minimizes incidence of complications. All published studies involving patients who underwent posterior spinal surgery with closure by PS or SS at index spine surgery were identified. Filtering by exclusion criteria identified 10 studies, 4 of which were comparative in nature and included both closures by PS and SS. Of these 4, none reported significant differences in postoperative outcomes between the groups. Across all studies, PS were involved in cases with higher baseline risk for wound complications and greater comorbidity burden. Closures by PS were significantly more likely to have had prior chemotherapy in 2 of the 4 (50%) studies (P = 0.014, P < 0.001) and radiation in 3 of the 4 (75%) studies (P < 0.001, P < 0.01, P < 0.001). In conclusion, closures by PS are frequently performed in higher risk cases, and use of PS in these closures may normalize the risk of wound complications to that of the normal risk cohort, though the overall level of evidence of the published literature is low.

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.

Disparities in Primary Spinal Osseous Malignant Bone Tumor Survival by Medicaid Status: A National Population-Based Risk Analysis.

BACKGROUND: The impact of Medicaid status on survival outcomes of patients with spinal primary malignant bone tumors (sPMBT) has not been investigated. METHODS: Using the SEER-Medicaid database, adults diagnosed between 2006 and 2013 with sPMBT including chordoma, osteosarcoma, chondrosarcoma, Ewing sarcoma, or malignant giant cell tumor (GCT) were studied. Five-year survival analysis was performed using the Kaplan-Meier method. Adjusted survival analysis was performed using Cox proportional-hazards regression controlling for age, sex, marital status, cancer stage, poverty level, vertebral versus sacral location, geography, rurality, tumor diameter, tumor grade, tumor histology, and therapy. RESULTS: A total of 572 patients with sPMBT (Medicaid: 59, non-Medicaid: 513) were identified. Medicaid patients were more likely to be younger (P < 0.001), Black (P < 0.001), live in high poverty neighborhoods (P = 0.006), have distant metastases at diagnosis (P < 0.001), and less likely to receive surgery (P = 0.006). The 5-year survival rate was 65.7% (chondrosarcoma: 70.0%, chordoma: 91.5%, Ewing sarcoma: 44.6%, GCT: 90.0%, osteosarcoma: 34.2%). Medicaid patients had significantly worse 5-year survival than non-Medicaid patients (52.0% vs. 67.2%, P = 0.02). Minority individuals on Medicaid were associated with an increased risk of cancer-specific mortality compared with White non-Medicaid patients (adjusted hazard ratio [aHR] = 2.51, [95% CI 1.18-5.35], P = 0.017). Among Medicaid patients, those who received surgery had significantly better survival than those who did not (64.5% vs. 30.6%, P = 0.001). For all patients, not receiving surgery (aHR = 1.90 [1.23-2.95], P = 0.004) and tumor diameter >50 mm (aHR=1.89 [1.10-3.25], P = 0.023) were associated with an increased risk of mortality. CONCLUSIONS: Medicaid patients may be less likely to receive surgery and suffer from poorer survival. These disparities may be especially prominent among minorities.

The epidemiology of crib-related head injuries: A ten-year nationwide analysis.

INTRODUCTION: Falls from cribs resulting in head injury are understudied and poorly characterized. The purpose of this study was to advance current understanding of the prevalence, descriptive characteristics of injury victims, and the types of crib fall-related head injuries (CFHI) using queried patient cases from the National Electronic Injury Surveillance System (NEISS) database. METHODS: Using the US Consumer Product Safety Commission's System NEISS database, we queried all CFHIs among children from over 100 emergency departments (EDs). Patient information regarding age, race, sex, location of the incident, diagnoses, ED disposition, and sequelae were analyzed. The number of CFHI from all US EDs during each year was also collected from the database. RESULTS: There were an estimated 54,799 (95% CI: 30,228-79,369) total visits to EDs for CFHIs between 2012 and 2021, with a decrease in incidence of approximately 20% during the onset of the COVID-19 pandemic (2019: 5616 cases, 2020: 4459 cases). The annual incidence of injuries showed no significant trend over the 10-year study period. An available subset of 1782 cases of head injuries from approximately 100 EDs was analyzed, and 1442 cases were included in final analysis. Injuries were sorted into three primary categories: unspecified closed head injury (e.g., closed head injury, blunt head trauma, or traumatic brain injury), concussion, or open head injury and skull fracture. Unspecified closed head injuries were the most common of all head injuries (95.4%, 1376/1442). Open head injuries (14/1442, 0.97%) and concussions 3.6% (52/1442, 3.6%) were rare. Most injuries involved children under the age of 1 (42.6%) compared to children who were 1, 2, 3, or 4-years old. About a fourth of patients had other diagnoses in addition to their primary injury including scalp/forehead hematomas, emesis, and contusions. Female patients were more likely to present with other diagnoses in addition to their primary head injury (Difference: 12.3%, 95% CI: 9.87%-15.4%, p < .0001). CONCLUSION: Despite minimum rail height requirements set by the Consumer Safety Product Commission (CPSC), head injuries associated with crib falls are prevalent in the United States. However, most injuries were minor with a vast majority of patients being released following examination and treatment.

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.

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.

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.

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.

Pediatric all-terrain vehicle (ATV) related head injury rates and patterns: A 10-year nationwide analysis.

INTRODUCTION: The use of all-terrain vehicles (ATVs) carries significant risk of permanent injury and death, disproportionately affecting children. These injuries commonly affect the head and are especially severe among children as they are often unhelmeted and more likely than adults to experience rollover injuries. Many studies examining patients with ATV-related injuries are single-center cohort studies, with few focusing specifically on head injuries. In the present study, we aimed to characterize the annual incidence of ATV-related head injuries between 2012 and 2021, classify and compare head injury types, and identify descriptive characteristics of ATV-related head injury victims. METHODS: Using the US Consumer Product Safety Commission's National Electronic Injury Surveillance System (NEISS) database, we queried all head injuries associated with operating or riding an ATV in children under 18 years-old from over 100 emergency departments (EDs). Patient information regarding age, race, sex, location of incident, diagnoses, and sequelae were analyzed. We also collected the estimated number of ATV-related head injuries from all US EDs using the NEISS algorithm provided by the database. RESULTS: Using the NEISS algorithm we identified 67,957 (95% CI: 43,608 - 92,305) total pediatric ATV-related head injuries between 2012 and 2021. The annual incidence of ATV-related head injury was similar throughout this study period except for a 20% increase during the COVID-19 pandemic period of 2019-2021 (2019: 6382 injuries, 2020: 6757 injuries, 2021: 7600 injuries). A subset of 1890 cases from approximately 100 EDs were then analyzed. Unspecified closed head injuries were the prevailing type of injury (38%, 900/1890), followed by concussions (27%, 510/1890). More severe injuries included intracranial hemorrhages in 91 children (3.8%, 91/1890). Injuries of all types were predominantly seen in 14-17 year-old's (780/1890, 41%) and in males (64.1%, 1211/1890). In addition, ATV-associated injuries were significantly more common in those coded as white (58.0%, 1096/1890) than any other racial group. ATV-associated accidents among children younger than 9 more commonly occurred at the home compared to accidents involving children older than 9 (57% vs. 32%, p < 0.0001). CONCLUSION: ATV-related head injuries cause a significant annual burden among children, with growing incidence in recent years. Further research may wish to explore potential benefits of helmet use and supervision of younger children in possible prevention of these accidents and their associated economic and non-economic costs.

The burden of unhelmeted motorcycle injury: A nationwide scoring-based analysis of helmet safety legislation.

INTRODUCTION: Motorcycle collisions comprise a large portion of motor vehicle injuries and fatalities with over 80,000 injuries and 5,500 fatalities per year in the United States. Unhelmeted riders have poor medical outcomes and generate billions in costs. Despite helmet use having been shown to lower the risk of neurological injury and death, helmet compliance is not universal, and legislation concerning helmet use also varies widely across the United States. METHODS: In this study, we systematically reviewed helmet-related statutes from all US jurisdictions. We evaluated the stringency of these statutes using a legislative scoring system termed the Helmet Safety Score (HSS) ranging from 0-7 points, with higher scores denoting more stringent statutes. Regression modeling was used to predict unhelmeted mortality using our safety scores. RESULTS: The mean score across all jurisdictions was 4.73. We found jurisdictions with higher HSS's generally had lower percentages of unhelmeted fatalities in terms of total fatalities as well as per 100,000 people and 100,000 registered motorcycles. In contrast, some lower-scoring jurisdictions had over 100 times more unhelmeted fatalities than higher-scoring jurisdictions. Our HSS significantly predicted unhelmeted motorcycle fatalities per 100,000 people (ß = -0.228 per 1-point increase, 95% CI: -0.288 to -0.169, p < .0001) and per 100,000 registered motorcycles (ß = -6.17 per 1-point increase, 95% CI: -8.37 to -3.98, p < .0001) in each state. Aspects of our score concerning helmet exemptions for riders and motorcycle-type vehicles independently predicted higher fatalities (p < .0001). Higher safety scores predicted lower unhelmeted fatalities. CONCLUSION: Stringent helmet laws may be an effective mechanism for decreasing unhelmeted mortality. Therefore, universal helmet laws may be one such mechanism to decrease motorcycle-related neurological injury and fatality burden. In states with existing helmet laws, elimination of exemptions for certain riders and motorcycle-type vehicles may also decrease fatalities.

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.

Spatiotemporal Distribution of Electrically Evoked Spinal Compound Action Potentials During Spinal Cord Stimulation.

OBJECTIVES: Recent studies using epidural spinal cord stimulation (SCS) have demonstrated restoration of motor function in individuals previously diagnosed with chronic spinal cord injury (SCI). In parallel, the spinal evoked compound action potentials (ECAPs) induced by SCS have been used to gain insight into the mechanisms of SCS-based chronic pain therapy and to titrate closed-loop delivery of stimulation. However, the previous characterization of ECAPs recorded during SCS was performed with one-dimensional, cylindrical electrode leads. Herein, we describe the unique spatiotemporal distribution of ECAPs induced by SCS across the medial-lateral and rostral-caudal axes of the spinal cord, and their relationship to polysynaptic lower-extremity motor activation. MATERIALS AND METHODS: In each of four sheep, two 24-contact epidural SCS arrays were placed on the lumbosacral spinal cord, spanning the L3 to L6 vertebrae. Spinal ECAPs were recorded during SCS from nonstimulating contacts of the epidural arrays, which were synchronized to bilateral electromyography (EMG) recordings from six back and lower-extremity muscles. RESULTS: We observed a triphasic P1, N1, P2 peak morphology and propagation in the ECAPs during midline and lateral stimulation. Distinct regions of lateral stimulation resulted in simultaneously increased ECAP and EMG responses compared with stimulation at adjacent lateral contacts. Although EMG responses decreased during repetitive stimulation bursts, spinal ECAP amplitude did not significantly change. Both spinal ECAP responses and EMG responses demonstrated preferential ipsilateral recruitment during lateral stimulation compared with midline stimulation. Furthermore, EMG responses were correlated with stimulation that resulted in increased ECAP amplitude on the ipsilateral side of the electrode array. CONCLUSIONS: These results suggest that ECAPs can be used to investigate the effects of SCS on spinal sensorimotor networks and to inform stimulation strategies that optimize the clinical benefit of SCS in the context of managing chronic pain and the restoration of sensorimotor function after SCI.

Neighborhood-level socioeconomic status, extended length of stay, and discharge disposition following elective lumbar spine surgery.

Background: In the context of increased attention afforded to hospital efficiency and improved but safe patient throughput, decreasing unnecessary hospital length of stay (LOS) is imperative. Given that lumbar spine procedures may be among a hospital's most profitable services, identifying patients at risk of increased healthcare resource utilization prior to surgery is a valuable opportunity to develop targeted pre- and peri-operative intervention and quality improvement initiatives. The purpose of the present investigation was to examine patient factors that predict prolonged LOS as well as discharge disposition following elective, posterior, lumbar spine surgery. Methods: We employed a retrospective cohort analysis on 779 consecutive patients treated with lumbar surgery without fusion. Our primary outcome measures were extended LOS (three or more midnights) and discharge disposition. Patient sociodemographic, procedural, and discharge characteristics were adjusted for in our analysis. Sociodemographic variables included Area of Deprivation Index (ADI), a comprehensive metric of socioeconomic status, utilizing income, education, employment, and housing quality based on patient zip code. Multivariable logistic regression and ordinal logistic regression analyses were performed to assess whether covariates were independently predictive of extended LOS and discharge disposition, respectively. Results: 779 patients were studied, with a median age of 66 years (±15) and a median LOS of 1 midnight (range, 1-10 midnights). Patients in the most disadvantaged ADI quintile (adjusted odds ratio, aOR 2.48 95% CI 1.15-5.47), those who underwent a minimally-invasive or tubular retractor surgery (aOR 3.03 95% CI 1.02-8.56), those who had an intra-operative drain placed (aOR 4.46 95% CI 2.53-7.26), who had a cerebrospinal fluid leak (aOR 3.46 95% CI 1.55-7.58), who were discharged anywhere but home (aOR 17.11 95% CI 9.24-33.00), and those who were evaluated by physical therapy (aOR 7.23 95% CI 2.13-45.30) or OT (aOR 2.20 95% CI 1.13-4.22) had a significantly increased chance of an extended LOS. Preoperative opioid use was not associated with an increased LOS following surgery (aOR 1.12 95% CI 0.56-1.46). Extended LOS was not associated with post-discharge emergency department representation or unplanned readmission within 90 days following discharge (p=0.148). Patients who were older (aOR 1.99 95% CI 1.62-2.48), in higher quintiles on ADI (3rd quintile; aOR 1.90 95% CI 1.12-3.23, 4th quintile; aOR 1.79, 95% CI 1.05-3.05, 5th quintile; aOR 2.16 95% CI 1.26-3.75), who had a CSF leak (aOR 2.18 95% CI 1.22-3.86), or who had a longer procedure duration (aOR 1.38 95% CI 1.17-1.62) were more likely to require additional services or be sent to a subacute facility upon discharge. Conclusions: Patient sociodemographics, along with procedural factors, and discharge disposition were all associated with an increased likelihood of prolonged LOS and resource intensive discharges following elective lumbar spine surgery. Several of these factors could be reliably identified pre-operatively and may be amenable to targeted preoperative intervention. Improving discharge disposition planning in the peri-operative period may allow for more efficient use of hospitalization and inpatient and post-acute resources.

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.

A Review of Functional Restoration From Spinal Cord Stimulation in Patients With Spinal Cord Injury.

Traumatic spinal cord injury often leads to loss of sensory, motor, and autonomic function below the level of injury. Recent advancements in spinal cord electrical stimulation (SCS) for spinal cord injury have provided potential avenues for restoration of neurologic function in affected patients. This review aims to assess the efficacy of spinal cord stimulation, both epidural (eSCS) and transcutaneous (tSCS), on the return of function in individuals with chronic spinal cord injury. The current literature on human clinical eSCS and tSCS for spinal cord injury was reviewed. Seventy-one relevant studies were included for review, specifically examining changes in volitional movement, changes in muscle activity or spasticity, or return of cardiovascular pulmonary, or genitourinary autonomic function. The total participant sample comprised of 327 patients with spinal cord injury, each evaluated using different stimulation protocols, some for sensorimotor function and others for various autonomic functions. One hundred eight of 127 patients saw improvement in sensorimotor function, 51 of 70 patients saw improvement in autonomic genitourinary function, 32 of 32 patients saw improvement in autonomic pulmonary function, and 32 of 36 patients saw improvement in autonomic cardiovascular function. Although this review highlights SCS as a promising therapeutic neuromodulatory technique to improve rehabilitation in patients with SCI, further mechanistic studies and stimulus parameter optimization are necessary before clinical translation.

Instrumentation choice and early radiographic outcome following lateral lumbar interbody fusion (LLIF): Lateral instrumentation versus posterior pedicle screw fixation.

Background: Lateral lumbar interbody fusion (LLIF) is a minimally invasive fusion procedure that may be performed with or without supplemental instrumentation. However, there is a paucity of evidence on the effect of supplemental instrumentation technique on perioperative morbidity and fusion rate in LLIF. Methods: A single-institutional retrospective review of patients who underwent LLIF for lumbar spondylosis was conducted. Patients were grouped according to supplemental instrumentation technique: stand-alone LLIF, LLIF with laterally placed instrumentation, or LLIF with posterior percutaneous pedicle screw fixation (PPSF). Outcomes included fusion rates, peri-operative complication, and reoperation; estimated blood loss (EBL); surgery duration; length of stay; and length of follow-up. Results: 82 patients underwent LLIF at 114 levels. 35 patients (42.7%) received supplemental lateral instrumentation, 30 (36.6%) received supplemental PPSF, and 17 (20.7%) underwent stand-alone LLIF. More patients in the lateral instrumentation group had prior lumbar fusion at adjacent levels (23/35, 65.71%) versus stand-alone (3/17, 17.6%) or PPSF (2/30, 6.67%) groups (p = 0.003). 4/17 patients (23.5%) with stand-alone LLIF and 4/35 patients (11.42%) with lateral instrumentation underwent reoperation, versus 0/30 with PPSF (p = 0.030). There was no difference in fusion rates between groups (p = 0.717). Operation duration was longer in patients with PPSF (p < 0.005) and length of follow-up was longer for PPSF than lateral instrumentation (p = 0.001). Choice of instrumentation group was a statistically significant predictor of reoperation. Conclusions: While rates of complete radiographic fusion on imaging follow-up didn't differ, patients receiving PPSF were less likely than stand-alone or lateral instrumentation groups to require reoperation, though operative time was significantly longer. Further study of choice of supplemental instrumentation with LLIF is indicated.

Navigation Techniques in Endoscopic Spine Surgery.

Endoscopic spine surgery (ESS) advances the principles of minimally invasive surgery, including minor collateral tissue damage, reduced blood loss, and faster recovery times. ESS allows for direct access to the spine through small incisions and direct visualization of spinal pathology via an endoscope. While this technique has many applications, there is a steep learning curve when adopting ESS into a surgeon's practice. Two types of navigation, optical and electromagnetic, may allow for widespread utilization of ESS by engendering improved orientation to surgical anatomy and reduced complication rates. The present review discusses these two available navigation technologies and their application in endoscopic procedures by providing case examples. Furthermore, we report on the future directions of navigation within the discipline of ESS.