Multicenter comparison of Chiari malformation type I presentation in children versus adults.

OBJECTIVE: Treatment for Chiari malformation type I (CM-I) often includes surgical intervention in both pediatric and adult patients. The authors sought to investigate fundamental differences between these populations by analyzing data from pediatric and adult patients who required CM-I decompression. METHODS: To better understand the presentation and surgical outcomes of both groups of patients, retrospective data from 170 adults and 153 pediatric patients (2000-2019) at six institutions were analyzed. RESULTS: The adult CM-I patient population requiring surgical intervention had a greater proportion of female patients than the pediatric population (p < 0.0001). Radiographic findings at initial clinical presentation showed a significantly greater incidence of syringomyelia (p < 0.0001) and scoliosis (p < 0.0001) in pediatric patients compared with adult patients with CM-I. However, presenting signs and symptoms such as headaches (p < 0.0001), ocular findings (p = 0.0147), and bulbar symptoms (p = 0.0057) were more common in the adult group. After suboccipital decompression procedures, 94.4% of pediatric patients reported symptomatic relief compared with 75% of adults with CM-I (p < 0.0001). CONCLUSIONS: Here, the authors present the first retrospective evaluation comparing adult and pediatric patients who underwent CM-I decompression. Their analysis reveals that pediatric and adult patients significantly differ in terms of demographics, radiographic findings, presentation of symptoms, surgical indications, and outcomes. These findings may indicate different clinical conditions or a distinct progression of the natural history of this complex disease process within each population, which will require prospective studies to better elucidate.

The Ultrasonic Bone Scalpel does not Outperform the High-Speed Drill: A Single Academic Experience.

BACKGROUND: Spinal decompression and osteotomies are conventionally performed using high-speed drills (HSDs) and rongeurs. The ultrasonic bone scalpel (UBS) is a tissue-specific osteotome that preferentially cuts bone while sparing the surrounding soft tissues. There is ongoing investigation into its ability to optimize peri- and postoperative outcomes in spine surgery. The purpose of this study was to compare the intraoperative metrics and complications during a transition period from HSD to UBS. METHODS: A single-institution, single-surgeon retrospective analysis was conducted of patients undergoing spine surgery from January 2020 to December 2021. Statistical analyses were performed to detect associations between the surgical technique and outcomes of interest. A P value < 0.05 was considered statistically significant. RESULTS: A total of 193 patients met the inclusion criteria (HSD, n = 100; UBS, n = 93). Multivariate logistic regression revealed similar durotomy (P = 0.10), nerve injury (P = 0.20), and reoperation (P = 0.68) rates. Although the estimated blood loss (EBL) and length of stay were similar, the operative time was significantly longer with the UBS (192.81 vs. 204.72 minutes; P = 0.03). Each subsequent surgery using the UBS revealed a 3.1% decrease in the probability of nerve injury (P = 0.026) but had no significant effects on the operative time, EBL, or probability of durotomy or reoperation. CONCLUSIONS: The UBS achieves outcomes on par with conventional tools, with a trend toward a lower incidence of neurologic injury. The expected reductions in EBL and durotomy were not realized in our cohort, perhaps because of a high proportion of revision surgeries, although these might be dependent on surgeon familiarity, among other operative factors. Future prospective studies are needed to validate our results and further refine the optimal application of this device in spine surgery.

Narrow and Ultranarrow Transitions in Highly Charged Xe Ions as Probes of Fifth Forces.

Optical frequency metrology in atoms and ions can probe hypothetical fifth forces between electrons and neutrons by sensing minute perturbations of the electronic wave function induced by them. A generalized King plot has been proposed to distinguish them from possible standard model effects arising from, e.g., finite nuclear size and electronic correlations. Additional isotopes and transitions are required for this approach. Xenon is an excellent candidate, with seven stable isotopes with zero nuclear spin, however it has no known visible ground-state transitions for high resolution spectroscopy. To address this, we have found and measured twelve magnetic-dipole lines in its highly charged ions and theoretically studied their sensitivity to fifth forces as well as the suppression of spurious higher-order standard model effects. Moreover, we identified at 764.8753(16) nm a E2-type ground-state transition with 500 s excited state lifetime as a potential clock candidate further enhancing our proposed scheme.

Sugammadex and blood loss during cervical spine fusion surgery.

Background and Aims: Sugammadex (SUG) has been associated with changes in coagulation studies. Most reports have concluded a lack of clinical significance based on surgical blood loss with SUG use at the end of surgery. Previous reports have not measured its use intraoperatively during ongoing blood loss. Our hypothesis was that the use of SUG intraoperatively may increase bleeding. Material and Methods: This was a single site retrospective study. Inclusion criteria were patients undergoing a primary posterior cervical spine fusion, aged over 18 years, between July 2015 and June 2021. The primary outcomes compared were intraoperative estimated blood loss (EBL) and postoperative drain output (PDO) between patients receiving SUG, neostigmine (NEO) and no NMB reversal agent. The objective was to determine if there was a difference in primary endpoints between patients administered SUG, NEO or no paralytic reversal agent. Primary endpoints were compared using analysis of variance with a P value of 0.05 used to determine statistical significance. Groups were compared using the Chi-squared test, rank sum or student's t test. A logistic regression model was constructed to account for differences between the groups. Results: There was no difference in median EBL or PDO between groups. The use of SUG was not associated with an increase in odds for >500 milliliters (ml) of EBL. Increasing duration of surgery and chronic kidney disease were both associated with an increased risk for EBL >500 ml. Conclusion: Intraoperative use of SUG was not associated with increased bleeding. Any coagulation laboratory abnormalities previously noted did not appear to have an associated clinical significance.

Comparison of Perioperative and Long-term Outcomes Following PEEK and Autologous Cranioplasty: A Single Institution Experience and Review of the Literature.

OBJECTIVE: Three-dimensionally (3D) printed polyether-ether-ketone (PEEK) implants are a relatively novel option for cranioplasty that have recently gained popularity. However, there is ongoing debate with respect to material efficacy and safety compared to autologous bone grafts. The purpose of this study was to offer our institution's experience and add to the growing body of literature. METHODS: A single-institution retrospective analysis of patients undergoing cranioplasties between 2016 and 2021. Patients were divided into PEEK and autologous cranioplasty cohorts. Parameters of interest included patient demographics as well as perioperative (<3 months postoperative) and long-term outcomes (>3 months postoperative). A P value < 0.05 was considered statistically significant. RESULTS: A total of 31 patients met inclusion criteria (PEEK: 15, Autologous: 16). Mean age of total cohort was 48.9 years (range 19-82 years). Modified Frailty Index (mFI) revealed greater rate of comorbidities among the Autologous group (P = 0.073), which was accounted for in statistical analyses. Multiple logistic regression model revealed significantly higher rate of surgical site infection in the Autologous cohort (31.3% vs. 0%, P = 0.011). Minor complications were similar between groups, while the Autologous group experienced significantly more major postoperative complications (50%) versus PEEK (13.3%) (P = 0.0291). Otherwise perioperative and long term complication profiles were similar between groups. Additionally, generalized linear model demonstrated both cohorts had similar mean hospital length of stay (LoS) (Autologous: 16.1 vs. PEEK: 10.7 days). CONCLUSIONS: PEEK cranioplasty implants may offer more favorable perioperative complication profiles with similar long-term complication rates and hospital LoS compared to autologous bone implants. Future studies are warranted to confirm our findings in larger series, and further examine the utility of PEEK in cranioplasty.

An Unusual Case of Neurenteric Cyst in a Patient with Split Cord Malformation.

Neurenteric cyst in a split cord malformation is a rare finding. We report an adult female becoming acutely symptomatic secondary to an expanding neurenteric cyst, though previous imaging had demonstrated stability. We discuss our workup and management with surgical resection and possible etiologies of her acute decline.

Impact of extent of resection and adjuvant therapy in diffuse gliomas of the spine.

BACKGROUND CONTENT: Diffuse gliomas of the spine (DGS)-consisting of intradural intramedullary glioblastoma, astrocytoma, and oligodendroglioma-are exceedingly rare tumors that account for about 2% of primary spinal cord tumors. Much is unknown about their optimal treatment regimen due to a relative lack of clinical outcome data. PURPOSE: To provide an updated analysis on treatment and outcomes in DGS. STUDY DESIGN/SETTING: Observational cohort study using The National Cancer Database (NCDB), a multicenter prospectively collected oncology outcomes database. A systematic literature review was also performed to compare the resulting data to previous series. PATIENT SAMPLE: Patients with histologically confirmed DGS from 2004 to 2018. OUTCOME MEASURES: Long-term overall survival and short-term 30/90-day postsurgical mortality, 30-day readmission, and prolonged hospital length of stay. METHODS: Impact of extent of resection and adjuvant therapy on overall survival was evaluated using Kaplan-Meier estimates and multivariable Cox proportional hazards regression. Univariate and multivariate logistic regression was used to analyze covariables and their prognostic impact on short-term surgical outcomes. RESULTS: Of the 747 cases that met inclusion criteria, there were 439 astrocytomas, 14 oligodendrogliomas, and 208 glioblastomas. Sixty percent (n=442) of patients received radiation, and 45% (n=324) received chemotherapy. Tumor histology significantly impacted survival; glioblastoma had the poorest survival (median survival time [MS]: 12.3 months), followed by astrocytoma (MS: 70.8 months) and oligodendroglioma (MS: 71.6 months) (p<.001). Gross total resection (GTR) independently conferred a survival benefit in patients with glioblastoma (hazard ratio [HR]: 0.194, p<0.001) and other WHO grade four tumors (HR: 0.223, p=.003). Adjuvant chemotherapy also improved survival in patients with glioblastoma (HR: 0.244, p=.007) and WHO grade four tumors (HR: 0.252, p<.001). Systematic literature review identified 14 prior studies with a combined DGS mortality rate of 1.3%, which is lower than the 4% real-world outcomes calculated from the NCDB. This difference may be explained by selection biases in previously published literature in which only centers with favorable outcomes publish their results. CONCLUSIONS: There remains a paucity of data regarding treatment paradigms and outcomes for DGS. Our analysis, the largest to date, demonstrates that GTR and adjuvant therapy independently improve survival for certain high-grade subgroups of DGS. This best-available data informs optimal management for such patients.

Practical Use of Augmented Reality Modeling to Guide Revision Spine Surgery: An Illustrative Case of Hardware Failure and Overriding Spondyloptosis.

BACKGROUND AND IMPORTANCE: Augmented reality (AR) is a novel technology with broadening applications to neurosurgery. In deformity spine surgery, it has been primarily directed to the more precise placement of pedicle screws. However, AR may also be used to generate high fidelity three-dimensional (3D) spine models for cases of advanced deformity with existing instrumentation. We present a case in which an AR-generated 3D model was used to facilitate and expedite the removal of embedded instrumentation and guide the reduction of an overriding spondyloptotic deformity. CLINICAL PRESENTATION: A young adult with a remote history of a motor vehicle accident treated with long-segment posterior spinal stabilization presented with increasing back pain and difficulty sitting upright in a wheelchair. Imaging revealed pseudoarthrosis with multiple rod fractures resulting in an overriding spondyloptosis of T6 on T9. An AR-generated 3D model was useful in the intraoperative localization of rod breaks and other extensively embedded instrumentation. Real-time model thresholding expedited the safe explanation of the defunct system and correction of the spondyloptosis deformity. CONCLUSION: An AR-generated 3D model proved instrumental in a revision case of hardware failure and high-grade spinal deformity.

Comparison of One-day Combined versus Staged Anterior and Posterior Cervical Decompression, Fixation, and Fusion.

AIM: To compare the perioperative outcomes between single-day combined or separate-day staged surgeries for cervical spinal stenosis. MATERIAL AND METHODS: A retrospective cohort analysis was conducted on consecutive patients admitted at a single institution between July 2015 and April 2019, who underwent either single-day combined or separate-day staged surgeries during the same hospitalization period. Demographics, comorbidities, hospital length of stay, and perioperative complications were compared between the patient groups. RESULTS: Eighty patients (combined surgery: n=68, staged surgery: n=12) were included. Dysphagia was the most commonly reported postoperative complication in 44/80 patients (55%). There were no significant differences in the baseline demographics between the two groups. The staged surgery group had significantly longer total time in the operating room (7.2 vs. 8.5 hours, p=0.002), longer duration of general anesthesia (6.7 vs. 7.6 hours, p=0.006), and higher incidence of postoperative delirium (12.1% vs. 50% p=0.005) than the combined surgery group. The mean hospital length of stay was similar in the two groups (combined surgery: 7.5 days vs. staged surgery: 15.1 days, p=0.09). CONCLUSION: Staged anterior and posterior cervical decompressions, stabilizations, and fusions are associated with longer total time in the operating room, longer duration of general anesthesia, and higher incidence of postoperative delirium than combined surgeries.

High Resolution Photoexcitation Measurements Exacerbate the Long-Standing Fe XVII Oscillator Strength Problem.

For more than 40 years, most astrophysical observations and laboratory studies of two key soft x-ray diagnostic 2p-3d transitions, 3C and 3D, in Fe XVII ions found oscillator strength ratios f(3C)/f(3D) disagreeing with theory, but uncertainties had precluded definitive statements on this much studied conundrum. Here, we resonantly excite these lines using synchrotron radiation at PETRA III, and reach, at a millionfold lower photon intensities, a 10 times higher spectral resolution, and 3 times smaller uncertainty than earlier work. Our final result of f(3C)/f(3D)=3.09(8)(6) supports many of the earlier clean astrophysical and laboratory observations, while departing by five sigmas from our own newest large-scale ab initio calculations, and excluding all proposed explanations, including those invoking nonlinear effects and population transfers.

Surgical management of a complex case of Charcot arthropathy of the spine: a case report.

Introduction: The authors present a case of a 55-year-old male with T10 complete paraplegia diagnosed with Charcot arthropathy of the spine (CAS). Case presentation: He presented to an outside institution with vomiting and productive cough with subsequent computed tomography (CT) and MRI imaging revealing L5 osteomyelitis and a paraspinal abscess. Given the patient's inability to remain in good posture in his wheelchair he underwent a multilevel vertebrectomy and thoracolumbar fusion. Due to multiple co-morbidities, surgical recovery was complex, ultimately requiring revision circumferential fixation. Discussion: CAS is an uncommon, long-term complication of traumatic spinal cord injury (SCI). Surgical management is often complex and associated with significant complications. Currently, a consensus on CAS prevention, specific surgical fixation techniques and post-surgical nursing care management is lacking. In this case report we provide our experience in the management of a complex case of CAS to aid in decision making for future neurosurgeons who encounter this sequela of traumatic SCI.

Early Experience with Electric Scooter Injuries Requiring Neurosurgical Evaluation in District of Columbia: A Case Series.

BACKGROUND: To decrease vehicular traffic in major metropolitan cities throughout the United States, multiple ridesharing companies have launched dockless electric scooters and bicycles throughout cities. From September 2017 through November 2018, Washington, DC, launched a 15-month dockless vehicle pilot program to allow for the rapid entry and growth of electric scooters within the metropolitan area. This rapid growth resulted in a number of minor and significant injuries. CASE DESCRIPTION: We reviewed the electronic medical record of The George Washington University Hospital to investigate and characterize the types of electric scooter-related injuries resulting in neurosurgical consultation in the 15-month period of the Washington, DC, scooter pilot program. Thirteen patients sustained injuries serious enough to merit neurosurgical consultation, including 1 patient whose symptoms required procedural intervention by a neurointerventional radiologist and another patient who was pronounced dead soon after arrival to the hospital. CONCLUSIONS: In this case series, we highlight more severe injuries that resulted in hospitalization or intervention, including skull fracture, central cord syndrome, and vertebral compression fracture. This case series aims to illustrate the potential severity of injuries related to electric scooters, raise awareness on the issues of safety and public health, and call for further investigation into injuries relating to electric scooters.

Return-to-active-duty rates after anterior cervical spine surgery in military pilots.

OBJECTIVESymptomatic cervical spondylosis with or without radiculopathy can ground an active-duty military pilot if left untreated. Surgically treated cervical spondylosis may be a waiverable condition and allow return to flying status, but a waiver is based on expert opinion and not on recent published data. Previous studies on rates of return to active duty status following anterior cervical spine surgery have not differentiated these rates among military specialty occupations. No studies to date have documented the successful return of US military active-duty pilots who have undergone anterior cervical spine surgery with cervical fusion, disc replacement, or a combination of the two. The aim of this study was to identify the rate of return to an active duty flight status among US military pilots who had undergone anterior cervical discectomy and fusion (ACDF) or total disc replacement (TDR) for symptomatic cervical spondylosis.METHODSThe authors performed a single-center retrospective review of all active duty pilots who had undergone either ACDF or TDR at a military hospital between January 2010 and June 2017. Descriptive statistics were calculated for both groups to evaluate demographics with specific attention to preoperative flight stats, days to recommended clearance by neurosurgery, and days to return to active duty flight status.RESULTSAuthors identified a total of 812 cases of anterior cervical surgery performed between January 1, 2010, and June 1, 2017, among active duty, reserves, dependents, and Department of Defense/Veterans Affairs patients. There were 581 ACDFs and 231 TDRs. After screening for military occupation and active duty status, there were a total of 22 active duty pilots, among whom were 4 ACDFs, 17 TDRs, and 2 hybrid constructs. One patient required a second surgery. Six (27.3%) of the 22 pilots were nearing the end of their career and electively retired within a year of surgery. Of the remaining 16 pilots, 11 (68.8%) returned to active duty flying status. The average time to be released by the neurosurgeon was 128 days, and the time to return to flying was 287 days. The average follow-up period was 12.3 months.CONCLUSIONSAdhering to military service-specific waiver guidelines, military pilots may return to active duty flight status after undergoing ACDF or TDR for symptomatic cervical spondylosis.

Cost-effectiveness of adult spinal deformity surgery in a military healthcare system.

OBJECTIVEAdult spinal deformity surgery is an effective way of treating pain and disability, but little research has been done to evaluate the costs associated with changes in health outcome measures. This study determined the change in quality-adjusted life years (QALYs) and the cost per QALY in patients undergoing spinal deformity surgery in the unique environment of a military healthcare system (MHS).METHODSPatients were enrolled between 2011 and 2017. Patients were eligible to participate if they were undergoing a thoracolumbar spinal fusion spanning more than 6 levels to treat an underlying deformity. Patients completed the 36-Item Short Form Health Survey (SF-36) prior to surgery and 6 and 12 months after surgery. The authors used paired t-tests to compare SF-36 Physical Component Summary (PCS) scores between baseline and postsurgery. To estimate the cost per QALY of complex spine surgery in this population, the authors extended the change in health-related quality of life (HRQOL) between baseline and follow-up over 5 years. Data on the cost of surgery were obtained from the MHS and include all facility and physician costs.RESULTSHRQOL and surgical data were available for 49 of 91 eligible patients. Thirty-one patients met additional criteria allowing for cost-effectiveness analysis. Over 12 months, patients demonstrated significant improvement (p < 0.01) in SF-36 PCS scores. A majority of patients met the minimum clinically important difference (MCID; 83.7%) and substantive clinical benefit threshold (SCBT; 83.7%). The average change in QALY was an increase of 0.08. Extended across 5 years, including the 3.5% discounting per year, study participants increased their QALYs by 0.39, resulting in an average cost per QALY of $181,649.20. Nineteen percent of patients met the < $100,000/QALY threshold with half of the patients meeting the < $100,000/QALY mark by 10 years. A sensitivity analysis showed that patients who scored below 60 on their preoperative SF-36 PCS had an average increase in QALYs of 0.10 per year or 0.47 over 5 years.CONCLUSIONSWith a 5-year extended analysis, patients who receive spinal deformity surgery in the MHS increased their QALYs by 0.39, with 19% of patients meeting the $100,000/QALY threshold. The majority of patients met the threshold for MCID and SCBT at 1 year postoperatively. Consideration of preoperative functional status (SF-36 PCS score < 60) may be an important factor in determining which patients benefit the most from spinal deformity surgery.

Cervical and Thoracolumbar Spine Injury Evaluation, Transport, and Surgery in the Deployed Setting.

This Cervical and Thoracolumbar Spine Injury Evaluation, Transport, and Surgery Clinical Practice Guideline (CPG) is designed to provide guidance to the deployed provider when they are treating a combat casualty who has sustained a spine or spinal cord injury. The CPG objective for the treatment and the movement of these patients is to maintain spinal stability through transport, perform decompression when urgently needed, achieve definitive stabilization when appropriate, avoid secondary injury, and prevent deterioration of the patient's neurological condition. Thorough and accurate documentation of the patient's neurological examination is crucial to ensure appropriate management decisions are made as the patient transits through the evacuation system. The use of this CPG should be in conjunction with good clinical judgment.

Spine Injuries Sustained by U.S. Military Personnel in Combat are Different From Non-Combat Spine Injuries.

Spine injuries are more prevalent among Iraq and Afghanistan veterans than among veterans of previous conflicts. The purpose of this investigation was to characterize the context, mode, and clinical outcomes of spine injuries sustained by U.S. military personnel in theater. Injury and clinical data from patients who sustained a spine injury in Iraq or Afghanistan between 2003 and 2008 were extracted from the Joint Theater Trauma Registry. Fischer's exact test was used to compare demographic variables between battle and nonbattle spine injuries. Two-sided t tests and univariate analyses were performed to analyze the association between injury context, mechanism, and severity with clinical outcome. A total of 307 patients sustained spine injuries in theater during the study period, and 296 had adequate data for analysis. Most injuries occurred in battle (69.6%), and these injuries were more likely to have an Injury Severity Score considered severe (44.7% vs. 20.0%; p < 0.001) or critical (13.6% vs. 5.6%; p = 0.0458). Blast was the most common mechanism of injury (42.2%) and was more likely to be blunt (81.6%) than penetrating (18.4%; p < 0.0001). Battle-associated spine injuries were most commonly caused by blasts, were more severe, and more likely to involve multiple spinal levels.

Performance of Cervical Arthroplasty at a Pseudarthrosed Level of a MultiLevel Anterior Cervical Discectomy and Fusion: Case Report.

OBJECTIVE: To present a conversion from an anterior cervical discectomy and fusion (ACDF) to cervical arthroplasty in a 40-year-old, active duty member and perform a review of the literature. METHODS: A helicopter pilot in the U.S. Army underwent a three-level ACDF in 2010 at a nonmilitary institution for symptoms of bilateral upper-extremity radiculopathy. His symptoms resolved; however, per regulations, he was grounded. The patient recently presented at our clinic for evaluation of axial neck and intrascapular pain with radiographic evaluation revealing pseudarthrosis at C6-7 with segmental motion without facet joint degeneration. Surgery was performed to remove the existing allograft and replace it with an artificial disc, thus restoring a motion segment. RESULTS: Postoperative imaging reveals appropriate placement of the artificial disc and range of motion at C6-7 with the patient reporting improvement in neck pain. He has since been granted a waiver to return to active flight status. CONCLUSIONS: Revision of ACDF to arthroplasty is an exceedingly rare procedure with only two cases reported in the literature. Here, the authors demonstrate use of the procedure for a military career-specific application. When facet joint degeneration or ankylosis is absent, restoration of motion can successfully, and safely, be achieved.

Military Neurosurgery: A Range of Service Options.

UNLABELLED: The pathway to military neurosurgical practice can include a number of accession options. This article is an objective comparison of fiscal, tangible, and intangible benefits provided through different military neurosurgery career paths. Neurosurgeons may train through active duty, reserve, or civilian pathways. These modalities were evaluated on the basis of economic data during residency and the initial 3 years afterwards. When available, military base pay, basic allowance for housing and subsistence, variable special pay, board certified pay, incentive pay, multiyear special pay, reserve drill pay, civilian salary, income tax, and other tax incentives were analyzed using publically available data. Civilians had lower residency pay, higher starting salaries, increased taxes, malpractice insurance cost, and increased overhead. Active duty service saw higher residency pay, lower starting salary, tax incentives, increased benefits, and almost no associated overhead including malpractice coverage. Reserve service saw a combination of civilian benefits with supplementation of reserve drill pay in return for weekend drill and the possibility of deployment and activation. Being a neurosurgeon in the military is extremely rewarding. From a financial perspective, ignoring intangibles, this article shows most entry pathways with initially modest differences between the cumulative salaries of active duty and civilian career paths and with higher overall compensation available from the reserve service option. These pathways become increasingly discrepant over time as civilian pay greatly exceeds that of military neurosurgeons. We hope that those curious about or considering serving in the United States military benefit from our accounting and review of these comparative paths. ABBREVIATIONS: FAP, Financial Assistance ProgramNADDS, Navy Active Duty Delay for SpecialistsTMS, Training in Medical Specialties.