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The Japanese Society for Spine Surgery and Related Research previously developed a diagnostic support tool for lumbar spinal stenosis (LSS-DST). Using the LSS-DST, general physicians can identify potential cases of LSS. However, in the LSS-DST, measurement of the ankle brachial pressure index (ABI) is required to exclude peripheral artery lesions in the lower limbs. We can expect further application of the LSS-DST if we can identify a simpler and easier method than ABI measurement. Therefore, in this large-scale, multicenter, cross-sectional study, we verified whether palpation of the posterior tibial (PT) artery could be used instead of ABI in the LSS-DST.This survey was conducted at 2177 hospitals and included 28,883 participants. The sensitivity and specificity of the original LSS-DST method using the ABI and that of the LSS-DST ver2.0 with PT artery palpation were assessed to screen their ability for diagnosing LSS, using the physicians' final diagnosis based on the patients' history, physical examination and radiographic findings as the gold standard.The sensitivity and specificity [95%CI] of the LSS-DST were 88.2% [87.5, 88.8] and 83.9% [83.4, 84.5], respectively, whereas the sensitivity and specificity of the LSS-DST ver2.0 were 87.7% [87.0, 88.3] and 78.3% [77.7, 78.9], respectively, indicating that LSS-DST ver2.0 is a useful screening tool for LSS with good sensitivity.When the item of ABI in the LSS-DST is replaced by palpation of the PT artery (LSS-DST ver2.0), its sensitivity is maintained as a screening tool for LSS.Level 3.

Surgery for dumbbell-type posterior mediastinal tumors (D-PMTs) is difficult because surgeons should confirm the tumor’s extension into the spinal cord and pay attention to the Adamkiewicz artery. We describe two patients of D-PMTs who underwent lateral- or prone-position video-assisted thoracic surgery (VATS). In patient 1 (a 70-year-old woman), the tumor extended to the spinal canal through the fourth thoracic intervertebral foramen. After hemi-laminectomies, she was moved to the lateral position, and the tumor was resected. In patient 2 (a 16-year-old boy), the tumor extended to the spinal canal through the seventh thoracic intervertebral foramen. Additionally, 320-row high-resolution computed tomography showed Adamkiewicz arteries running through the sixth and eighth thoracic intervertebral foramina. After laminectomy, the tumor was resected without repositioning. Prone-position VATS is a useful approach for D-PMTs because it provides a better view of the vertebrae compared with the lateral position. We discuss the advantages and disadvantages of both approaches.

Background The latest clinical guidelines are mandatory for physicians to follow when practicing evidence-based medicine in the treatment of low back pain. Those guidelines should target not only Japanese board-certified orthopaedic surgeons, but also primary physicians, and they should be prepared based entirely on evidence-based medicine. The Japanese Orthopaedic Association Low Back Pain guideline committee decided to update the guideline and launched the formulation committee. The purpose of this study was to describe the formulation we implemented for the revision of the guideline with the latest data of evidence-based medicine. Methods The Japanese Orthopaedic Association Low Back Pain guideline formulation committee revised the previous guideline based on a method for preparing clinical guidelines in Japan proposed by Medical Information Network Distribution Service Handbook for Clinical Practice Guideline Development 2014. Two key phrases, "body of evidence" and "benefit and harm balance" were focused on in the revised version. Background and clinical questions were determined, followed by literature search related to each question. Appropriate articles were selected from all the searched literature. Structured abstracts were prepared, and then meta-analyses were performed. The strength of both the body of evidence and the recommendation was decided by the committee members. Results Nine background and nine clinical qvuestions were determined. For each clinical question, outcomes from the literature were collected and meta-analysis was performed. Answers and explanations were described for each clinical question, and the strength of the recommendation was decided. For background questions, the recommendations were described based on previous literature. Conclusions The 2019 clinical practice guideline for the management of low back pain was completed according to the latest evidence-based medicine. We strongly hope that this guideline serves as a benchmark for all physicians, as well as patients, in the management of low back pain.

Abdominal oblique muscle injury is characterized by acute pain and localized tenderness over the lateral trunk. This injury is particularly common among throwing athletes, and usually presents as anterolateral abdominal wall pain. Imaging evidence is scarce in regard to whether oblique muscle injury at its junction with the thoracolumbar fascia can instead present with low back pain. A high school baseball player with unilateral low back pain was referred to us with a different diagnosis. Careful palpation and magnetic resonance imaging guided our care, and the patient returned to high-level competition after 7 weeks of conservative treatment, with no report of recurrence in the subsequent 12 months. Oblique muscle injury at its junction with the thoracolumbar fascia should be added to the differential diagnosis for throwing athletes with unilateral low back pain following a torque movement.

Thoracic ossification of the ligamentum flavum (OLF) is a pathological condition that causes myelopathy, with unilateral lower extremity pain rarely a feature in the presenting complaint. Moreover, most symptomatic cases of thoracic OLF occur in middle-aged men, with younger individuals rarely affected. We present a rare case of severe and chronic unilateral buttock and leg pain mimicking sciatica due to thoracic OLF in a professional baseball pitcher. A 28-year-old, right-handed, Japanese professional baseball pitcher experienced intractable left leg pain with numbness and spasticity. After the initial presentation, extensive testing focusing on lumbar, hip, and pelvis lesions failed to identify a cause for the pain. One year after onset, careful neurological examination showed signs of upper motor neuron disturbance, and thoracic computed tomography and magnetic resonance imaging revealed thoracic OLF at the level of the thoracolumbar junction. After resection of the thoracic OLF, the pain, numbness, and spasticity completely resolved. He resumed full training and was pitching in top condition within four months after surgery. Though rare, thoracic OLF should be considered in the differential diagnosis of lower extremity pain in young athletes, especially amongst high-level baseball pitchers.

Background: Our previous report described the development of a self-administered questionnaire to screen patients for cervical myelopathy (SQC). For clinical application, the characteristics of the SQC should be verified. Methods: Participants comprised 129 patients (94 men, 35 women) with cervical myelopathy who underwent operative treatment. SQC score was calculated before surgery and patients were divided into a positive group (score ≥6) and negative group (score

It remains unclear whether musculoskeletal diseases are risk factors for dementia development. This prospective cohort study of community-dwelling residents aimed to clarify the impact of lumbar spinal stenosis (LSS) on dementia development.We included participants aged ≥ 65 years from the Locomotive Syndrome and Health Outcomes in the Aizu cohort study. LSS was diagnosed using the validated LSS diagnostic support tool. Dementia development between 2008 and 2015 was investigated using official long-term care insurance certification data. We analysed the effects of LSS on dementia development after adjusting for potential confounders, like age, sex, diabetes, depressive symptoms, hip and knee joint osteoarthritis, daily activity, and smoking habit.We included 1220 patients in the final analysis. The incidence of dementia was significantly higher in the LSS group [48 of 444 (10.8%)] than in the control group [34 of 776 (4.4%)]. Multivariable analysis using multiple imputations revealed that the confidence interval for the adjusted odds ratio of LSS for dementia development was 1.87 (95% confidence interval; 1.14-3.07).We clarified that LSS is an independent risk factor for dementia development. Our findings suggest the importance of considering the risk of dementia in the decision-making process for the treatment of LSS.

Purpose With spinal deformities, mental health can deteriorate due to sagittal imbalance of the spine. The purpose of this study was to clarify the relationship between sagittal imbalance and symptoms of depression among local residents in the community. Methods This study used data from the Locomotive Syndrome and Health Outcomes in Aizu Cohort Study (LOHAS) in 2010. The sagittal vertical axis (SVA) was identified as an indicator of sagittal imbalance. Symptoms of depression were assessed using the 5-item version of the Mental Health Inventory. Participants were classified into three categories based on the SVA balance as normal ( 95 mm). To evaluate the relationship between sagittal imbalance of the spine and symptoms of depression, the adjusted risk ratio (RR) and the 95% confidence interval (CI) were calculated using a generalized linear model with Poisson link. Results There were 786 participants included in the statistical analysis. Overall, the mean age was 68.1 y (standard deviation, 8.8 y), and 39.4% were men. The prevalence of symptoms of depression by SVA category was 18.6% for normal, 23.8% for moderate, and 40.6% for severe. On multivariate analysis, the RR of SVA for symptoms of depression compared to the normal category was 1.12 (95% CI 0.7–1.70) for the moderate category and 2.29 (95% CI 1.01–5.17) for the severe category. Conclusion In local community residents, sagittal imbalance had a significant association with symptoms of depression.

Aim The Fukushima Daiichi Nuclear Power Plant accident dramatically changed the lifestyle of residents who lived near the plant. We evaluated the association of metabolic syndrome (MetS) with specific lifestyle- and disaster-related factors in residents following the accident. Methods This cross-sectional study included 20,920 residents who underwent both the Comprehensive Health Check and the Mental Health and Lifestyle Survey from June 2011 to March 2012. Associations between MetS and lifestyle- and disaster-related factors, including psychological distress (post-traumatic stress disorder [PTSD]), were estimated using logistic regression analysis, adjusted for demographic and lifestyle factors, in 2019. Results MetS was present in 30.4% of men and 11.5% of women. There were significant differences in smoking, drinking status, and PTSD prevalence between subjects with and without MetS. Multivariable logistic regression analysis showed that age, quitting smoking, and low physical activity were significantly associated with MetS. Moreover, PTSD and light to moderate drinking were also significantly associated with MetS in women. Conclusions Lifestyle- and disaster-related factors, including PTSD, were associated with MetS among subjects who lived near the Fukushima Daiichi Nuclear Power Plant accident.

Observations of electron-hole asymmetry in transport through graphene devices at high magnetic field challenge prevalent models of the graphene quantum Hall effect. Here, we study this asymmetry both in conventional magnetotransport and in scanning gate microscopy maps measured in an encapsulated graphene constriction. We reveal that the presence of upstream modes and local doping in the vicinity of electrical contacts leads to a totally different picture of topological breakdown for electrons and holes, explaining the observed asymmetry., 5 pages, 5 figures

BackgroundThe Great East Japan Earthquake and the Fukushima Daiichi nuclear disaster forced the evacuation of residents and led to many changes in lifestyle for the evacuees. The Comprehensive Health Check was implemented to support the prevention of lifestyle-related disease and we analyzed the effect of prolonged evacuation (average of 3.0 years) on the new onset of hyper-LDL cholesterolemia.MethodsThe study participants were Japanese adults living near the Fukushima Daiichi nuclear power plant in Fukushima Prefecture. Annual health checkups focusing on metabolic syndromes were conducted for persons ≥ 40 years by the Specific Health Checkup. Based on data from annual checkups from 2011 or 2012, we followed 18,670 non-hyper-LDL cholesterolemia who underwent at least one other annual checkup during 2013-2015.ResultsWe found that the new onset of hyper-LDL cholesterolemia was significantly by 31% higher in evacuees than in non-evacuees. Evacuees had a significantly higher prevalence of obesity, hypertension, and diabetes, and higher frequency of weight change. Furthermore, logistic regression model analysis showed that the evacuation was significantly associated with the new onset of hyper-LDL cholesterolemia after adjusting age, gender, body mass index (BMI), smoking habit, alcohol consumption, diabetes, weight change, sleep deprivation, and exercise.ConclusionsThe findings of the present study suggest that prolonged evacuation after a disaster is a risk factor for the new onset of hyper-LDL cholesterolemia, and lead to an increase in cardiovascular disease. It is therefore important to follow-up evacuees and recommend lifestyle changes where necessary.

STUDY DESIGN Retrospective cohort study. OBJECTIVE To clarify the poor patient satisfaction after lumbar spinal surgery in elderly patients. SUMMARY OF BACKGROUND DATA As the global population continues to age, it is important to consider the surgical outcome and patient satisfaction in the elderly. No studies have assessed patient satisfaction in elderly patients undergoing surgical treatment and risk factors for poor satisfaction in elderly patients after lumbar spinal surgery. MATERIALS AND METHODS A retrospective multicenter survey was performed in 169 patients aged above 80 years who underwent lumbar spinal surgery. Patients were followed up for at least 1 year after surgery. We assessed patient satisfaction from the results of surgery by using a newly developed patient questionnaire. Patients were assessed by demographic data, surgical procedures, complications, reoperation rate, pain improvement, and risk factors for poor patient satisfaction with surgery for lumbar spinal disease. RESULTS In total, 131 patients (77.5%, G-group) were satisfied and 38 patients (22.5%, P-group) were dissatisfied with surgery. The 2 groups did not differ significantly in baseline characteristics and surgical data. Postoperative visual analog scale score for low back pain and leg pain were significantly higher in the P-group than in the G-group (low back pain: G-group, 1.7±1.9 vs. P-group, 5.2±2.5, P

Time-dependent density functional theory (TDDFT) has been applied to the calculation of absorption spectra for two-dimensional atomic layer materials: mono-layer and bi-layer hexagonal boron nitride (h-BN) and mono-layer transition metal dichalcogenides, MoS2 and MoSe2. We reveal that the character of the first bright exciton state of bi-layer h-BN is dependent on the layer stacking type through the use of many-body perturbation theory (MBPT) calculations, i.e., the electron and hole in the AA' stacking are present in the same layer (an intralayer exciton) while the A'B stacking exhibits an interlayer exciton. We demonstrate that the TDDFT approach with the meta-generalized gradient approximation to the exchange-correlation (XC) potential and the Bootstrap XC kernel can capture the characteristics of the absorption peaks that correspond to these excitons without computationally heavy GW and Bethe-Salpeter equation calculations. We also show that the TDDFT method can capture the qualitative features of the absorption spectra for mono-layer transition metal dichalcogenides, MoS2 and MoSe2, although the exciton binding energies are underestimated. This study elucidates the usefulness of the TDDFT approach for the qualitative investigation of the optical properties of two-dimensional atomic layer materials.

International audience; Graphene is a very promising test bed for the field of electron quantum optics. However, a fully tunable and coherent electronic beam splitter is still missing. We report the demonstration of electronic beam splitters in graphene that couple quantum Hall edge channels having opposite valley polarizations. The electronic transmission of our beam splitters can be tuned from zero to near unity. By independently setting the beam splitters at the two corners of a graphene p−n junction to intermediate transmissions, we realize a fully tunable electronic Mach-Zehnder interferometer. This tunability allows us to unambiguously identify the quantum interferences due to the Mach-Zehnder interferometer, and to study their dependence with the beam-splitter transmission and the interferometer bias voltage. The comparison with conventional semiconductor interferometers points toward universal processes driving the quantum decoherence in those two different 2D systems, with graphene being much more robust to their effect.

Study DesignObservational cohort study.PurposeTo assess the surgical outcomes of posterior decompression and fusion for cervical myelopathy in patients with athetoid cerebral palsy.Overview of LiteraturePatients with athetoid cerebral palsy demonstrate involuntary movements and develop severe cervical spondylosis with kyphosis. In these patients, surgery is often performed at an early age because of myelopathy. A few studies have reported about the long-term outcomes of surgical treatment; however, they contain insufficient information.MethodsFrom 2003 to 2008, 13 patients with cervical myelopathy due to athetoid cerebral palsy underwent posterior fusion surgery and were included in this study. The Japanese Orthopaedic Association (JOA) score, neck disability index (NDI), C2–7 angle on radiography, and need for additional surgical treatment were examined at 1 and 5 years postoperatively.ResultsThe mean C2–7 angle was −10.5°±21.1° preoperatively and was corrected to −2.9°±13.5° immediately postoperatively. This improvement was maintained for 5 years. The JOA score was 9.5±2.5 preoperatively and 12.2±1.7 at the 5-year follow-up. NDI was 17±6.9 preoperatively and 16±7.5 at the 5-year follow-up. Patient satisfaction with surgery on a 100-point scale was 62.2±22.5 at the 5-year follow-up. Three patients needed additional surgery for loosening of screws. These results demonstrate good surgical outcomes for posterior fusion at 5 years.ConclusionsPosterior decompression and fusion should be considered a viable option for cervical myelopathy in patients with athetoid cerebral palsy.

Background and Objectives: The high prevalence of lumbar spinal stenosis (LSS) and its negative impact on quality of life in the elderly is well known. However, the longitudinal time course of LSS symptoms remains unclear. The purpose of this study was to clarify the longitudinal time course and associated factors of LSS symptoms over a period of six years in a community. Materials and Methods: This study was conducted with data prospectively collected in 2004 and 2010 under a retrospective design. In 2004, 1578 subjects (age range: 40 to 79 years) were interviewed on LSS symptoms using a specially designed and validated questionnaire. In 2010, a follow-up study was performed by mail, to which 789 subjects of the 2004 study population responded. Considering that the presence of osteoarthritis (OA) of the knee or hip may influence the participants’ answers in the questionnaire, analysis was performed in all 789 subjects with and 513 subjects without either knee or hip OA. Changes in LSS symptoms between the initial and the 6-year survey were investigated. Multiple logistic regression analysis was used for detecting the risk factors for LSS symptom presence at the six-year follow-up. Results: 1. At the six-year follow-up, more than half of the subjects who showed LSS symptoms at the initial analysis became LSS-negative, and 12–15% of those who were LSS-negative became LSS-positive. 2. From the multiple logistic regression analysis, a lower Roland-Morris Disability Questionnaire (RDQ) score and a positive LSS symptom at the initial analysis were detected as predictive factors of the presence of LSS symptoms at the six-year follow-up in the total number of subjects, as well as just in those who did not have either knee or hip OA. Conclusions: More than half of the subjects who were LSS-positive at their initial assessment still experienced improvement in their symptoms even after 6 years. This means that both LSS symptoms and their time course vary from person to person. Predictive factors for the presence of LSS symptoms during the six-year follow-up period were RDQ score and positive LSS symptoms.

Introduction: With an aging population, the proportion of patients aged 80 years requiring cervical surgery is increasing. Surgeons are concerned with the high incidence of complications in this population, because “age” itself has been reported as a strong risk factor for complications. However, it is still unknown which factors represent higher risk among these elderly patients. Therefore, this study was conducted to identify the risk factors related to surgical complications specific to elderly patients by analyzing the registry data of patients aged 80 years who underwent cervical surgery. Methods: We retrospectively studied multicenter collected registry data using multivariate analysis. Sixty-six patients aged 80 years who underwent cervical surgery and were followed up for more than one year were included in this study. Preoperative patient demographic data, including comorbidities and postoperative complications, were collected from multicenter registry data. Complications were considered as major if they required invasive intervention, caused prolonged morbidity, or resulted in prolongation of hospital stay. Logistic regression analysis was performed to analyze the risk factors for complications. A p-value of

Study Design: Retrospective study of registry data. Objectives: Aging of society and recent advances in surgical techniques and general anesthesia have increased the demand for spinal surgery in elderly patients. Many complications have been described in elderly patients, but a multicenter study of perioperative complications in spinal surgery in patients aged 80 years or older has not been reported. Therefore, the goal of the study was to analyze complications associated with spine surgery in patients aged 80 years or older with cervical, thoracic, or lumbar lesions. Methods: A multicenter study was performed in patients aged 80 years or older who underwent 262 spinal surgeries at 35 facilities. The frequency and severity of complications were examined for perioperative complications, including intraoperative and postoperative complications, and for major postoperative complications that were potentially life threatening, required reoperation in the perioperative period, or left a permanent injury. Results: Perioperative complications occurred in 75 of the 262 surgeries (29%) and 33 were major complications (13%). In multivariate logistic regression, age over 85 years (hazard ratio [HR] = 1.007, P = 0.025) and estimated blood loss ≥500 g (HR = 3.076, P = .004) were significantly associated with perioperative complications, and an operative time ≥180 min (HR = 2.78, P = .007) was significantly associated with major complications. Conclusions: Elderly patients aged 80 years or older with comorbidities are at higher risk for complications. Increased surgical invasion, and particularly a long operative time, can cause serious complications that may be life threatening. Therefore, careful decisions are required with regard to the surgical indication and procedure in elderly patients.

Study Design:Retrospective database analysis.Objective:Spine surgeries in elderly patients have increased in recent years due to aging of society and recent advances in surgical techniques, and postoperative complications have become more of a concern. Postoperative delirium is a common complication in elderly patients that impairs recovery and increases morbidity and mortality. The objective of the study was to analyze postoperative delirium associated with spine surgery in patients aged 80 years or older with cervical, thoracic, and lumbar lesions.Methods:A retrospective multicenter study was performed in 262 patients 80 years of age or older who underwent spine surgeries at 35 facilities. Postoperative complications, incidence of postoperative delirium, and hazard ratios of patient-specific and surgical risk factors were examined.Results:Postoperative complications occurred in 59 of the 262 spine surgeries (23%). Postoperative delirium was the most frequent complication, occurring in 15 of 262 patients (5.7%), and was significantly associated with hypertension, cerebrovascular disease, cervical lesion surgery, and greater estimated blood loss ( P < .05). In multivariate logistic regression using perioperative factors, cervical lesion surgery (odds ratio = 4.27, P < .05) and estimated blood loss ≥300 mL (odds ratio = 4.52, P < .05) were significantly associated with postoperative delirium.Conclusions:Cervical lesion surgery and greater blood loss were perioperative risk factors for delirium in extremely elderly patients after spine surgery. Hypertension and cerebrovascular disease were significant risk factors for postoperative delirium, and careful management is required for patients with such risk factors.

Background Numbness in the soles of both feet at rest or bowel/bladder dysfunction can occur in patients with lumbar spinal stenosis (LSS), especially in patients with cauda equina lesions. The purpose of this study was to clarify the relationship between cauda equina symptoms at rest and quality of life (QOL) in LSS patients using standardized questionnaires developed for the Japanese population. Methods A survey was conducted in 564 hospitals and general practice clinics nationwide from December 1, 2011 to December 31, 2012. All patients who visited hospital or clinic because of low back pain were included. Patients were diagnosed with LSS using the LSS-Diagnostic Support Tool (LSS-DST), and the severity of the disease was measured using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) for quality of life. Presence of both sole numbness and/or bowel/bladder dysfunction were determined by medical interview. 3647 patients were diagnosed with LSS according to the results of the LSS-DST. 1294 of these patients (35.5%) had symptoms at rest. Of these patients, 359 patients with sole numbness, 135 patients with bowel/bladder dysfunction, and 52 patients with both numbness and bowel/bladder dysfunction were compared to the patients without rest symptoms (n = 2182). Comparisons between groups with or without sole numbness and bowel/bladder dysfunction were performed using statistical analysis of JOABPEQ responses in the categories of pain-related disorder, lumbar spine disorder, gait disturbance, social life disturbance, and psychological disorder. Results All groups with sole numbness and/or bowel/bladder dysfunction had statistically lower (worse) scores in all categories of the JOABPEQ compared to the group without these symptoms at rest. Conclusion LSS patients having numbness in the soles of both feet at rest or bowel/bladder dysfunction had lower measurements of QOL and activities of daily living than those patients without symptoms at rest. These symptoms appear to be related to QOL of LSS patients.

We investigated positron states at Li-adsorbed Al(100) surfaces using \textit{ab-initio} two-component density functional theory. The results thus obtained by using semi-local electron-positron (e-p) correlation functionals with the generalized gradient approximation well reproduce the experimental results, showing that reliable e-p correlation functionals are needed to properly describe the various properties of positron surface state.

The patient was an 86-year-old woman with back pain after a fall. She had no neurological findings at the initial visit. Plain radiographs and magnetic resonance imaging (MRI) showed diffuse idiopathic skeletal hyperostosis (DISH) and a Th10 fracture. Two weeks later, she started gait exercise with immobilization by a rigid orthosis. Twenty-five days later, she presented with paralysis and numbness of her legs. Computed tomography (CT) showed anterior expansion in the vertebral body of Th10. MRI showed an intramedullary high-intensity area on T2-weighted images at the same level. She was diagnosed as having delayed paraplegia after a Th10 fracture and transferred to our hospital for surgery. Laminectomy of Th10, posterior fusion from Th7 to L1 with pedicle screws and hooks to Th6 and L1 laminae, anterior fusion from Th9 to Th11 with a plate, and autologous bone grafting were performed simultaneously. The patient's paralysis improved, and she started gait exercise with no limitation of bed rest and without an orthosis after surgery. At 8 days after surgery, she again presented with low back pain and paralysis in her legs. CT revealed an L1 fracture, which was the caudal end of the surgical fusion. The decreased kyphosis after surgery compared to that at pre-injury might have caused a subsequent horizontal shear force to L1 when the patient sat on the bed and when she walked. In conclusion, to avoid postoperative adjacent vertebral fracture after fusion, appropriate correction of spinal alignment to that at pre-injury is needed for vertebral fractures in patients with DISH.

The time-dependent variational principle is used to optimize the linear and nonlinear parameters of Gaussian basis functions to solve the time-dependent Schrodinger equation in 1 and 3 dimensions for a one-body soft Coulomb potential in a laser field. The accuracy is tested comparing the solution to finite difference grid calculations using several examples. The approach is not limited to one particle systems and the example presented for two electrons demonstrates the potential to tackle larger systems using correlated basis functions., Comment: 12 pages, 10 figures, submitted to Physical Review E

Background: Cauda equina syndrome (CES) is a severe neurologic condition marked by progressive loss of function of the neurologic elements in the spinal canal below the termination of the spinal cord. This article reports an instructive case of CES with acute aggravation of neuropathy after catheter ablation for atrial fibrillation. Patient concerns: A 63-year-old Japanese man underwent catheter ablation for atrial fibrillation. Because he complained of severe low back pain and numbness in the posterior of both lower limbs while in the supine position, he was given analgesia with pentazocine and sedated with propofol, and the procedure continued. He was then forced to maintain lumbar extension while in the supine position for 13 hours. After the treatment, he noticed urination disor-der, numbness, and paralysis of both lower limbs. Diagnosis: Neurological findings included sensory impairment and motor deficit of L5 and below, including bowel/bladder dysfunction. Lumbar magnetic resonance imaging showed severe lumbar spinal stenosis at L4-L5. He was diagnosed with CES due to lumbar spinal stenosis. Interventions: The patient received emergency surgery for L4-L5 decompression. Decompression of the spinal canal was achieved 33 hours after the start of catheterization. Outcomes: The patient’s leg symptoms improved immediately after surgery, and he was able to walk with a walker. On postoperative day 6, the urinary catheter was removed. However, he experienced urinary retention and needed intermittent self-directed urination. Five months after surgery, he was able to urinate on his own, and completed the intermittent self-directed urination. Nine months after surgery, his muscle strength had recovered almost completely, and he was able to walk with a cane. However, bladder dysfunction such as frequent urination and residual urination remained 4 years after surgery. Lessons: If the supine position elicits low back pain and leg numbness, the presence of lumbar spinal stenosis should be considered. Forcing patients with such symptoms into a sustained posture can lead to CES.