Impact of east Japan earthquake disaster with massive tsunami for prevalence of Takotsubo syndrome – a multicenter regional registry before and after east Japan earthquake disaster

Background

Previous studies demonstrated Takotsubo syndrome (TS) was easy provoked by earthquake disaster. However, a previous other regional report demonstrated TS was not increased after 2011 east Japan earthquake disaster. The purpose of this study was to clarify incidence of TS after the earthquake disaster in Iwate prefecture during long term period.

Method

Consecutive hospitalized TS patients were registered during 8 years between 2009 and 2016 in our medical university and five Iwate prefecture hospitals. Moreover, patients were divided into two groups, i.e., those with the inland and those with tsunami-stricken area groups. Prevalence of TS were calculated by standard incidence ratio (SIR) before and after the earthquake disaster. Moreover, long-term prognosis in the both groups was compared using Kaplan-Meier analysis.

Results

A total of 112 TS (male 25 and female 87) were registered from acute coronary syndrome registry in each hospital (n=4,163). Averaged age was 75.3 year-old. A total number of TS just after the two months of the earthquake (March and April 2011) was nine and significance monthly variation was observed comparing with the other months (p=0.029). SIR before and after the disaster is as following Figure. There were no significant differences for long-term prognosis between the two groups (p=0.20).

Conclusion

Incidence of TS was increased in acute phase after east Japan earthquake disaster. However, significance increases were maintained during long-term period, although number of TS was decreased after acute phase. TS is increased not only acute but also chronic phase after the serious earthquake disaster.

Standard incidence ratio

Funding Acknowledgement

Type of funding source: None

Dynamic nuclear polarization and ESR hole burning in As doped silicon

We present an experimental study of the Dynamic Nuclear Polarization (DNP) of ²⁹Si nuclei in silicon crystals of natural abundance doped with As in the temperature range 0.1-1 K and in a strong magnetic field of 4.6 T. This ensures a very high degree of electron spin polarization, extremely slow nuclear relaxation and optimal conditions for realization of Overhauser and resolved solid effects. We found that the solid effect DNP leads to the appearance of a pattern of holes and peaks in the ESR line, separated by the super-hyperfine interaction between the donor electron and ²⁹Si nuclei closest to the donor. On the contrary, the Overhauser effect DNP mainly affects the remote ²⁹Si nuclei having the weakest interaction with the donor electron. This leads to the appearance of a very narrow (≈3 mG wide) hole in the ESR line. We studied relaxation of the holes after burning, which is caused by the nuclear spin diffusion. Analyzing the dynamics of the hole in the spectrum with a simple one-dimensional diffusion model leads to a value of the diffusion coefficient D = 8(3) × 10^-9 G² s^-1. Our data indicate that the spin diffusion is not completely prevented even in the frozen core near the donors. The emergence of the narrow hole after the Overhauser DNP may be explained by a partial "softening" of the frozen core caused by decoupling of the donor electron and remote ²⁹Si nuclei.

Neurological function following early versus delayed decompression surgery for drop foot caused by lumbar degenerative diseases

The purpose of this study was to investigate the effectiveness of early (<72 h) versus late (≥72 h) decompression surgery after the onset of drop foot caused by root disorder in lumbar degenerative diseases (LDDs). Data were included from 60 patients who underwent decompression surgery for drop foot caused by LDDs, including lumbar disk herniation or lumbar spinal stenosis. The primary outcome was ordinal change in the manual muscle test (MMT) at 2 years follow-up. Secondary outcomes included changes in the Japanese Orthopedic Association's (JOA) score. The early- and late-stage surgery groups included 20 and 40 patients with mean durations from the onset of drop foot to operation of 0.8 days (range, 0-3 days) and 117.1 days (range, 10-891 days), respectively. There was no significant difference (p = 0.33) between the early- and late-stage surgery groups in the improvement of MMT scores to >4 (90% versus 80%, respectively). However, more patients in the early-stage group achieved an MMT score >5 compared with those in the late-stage surgery group (80% versus 45%; p = 0.03). Furthermore, the recovery rate of JOA scores was significantly higher in the early-stage (89.1%) compared with the late-stage surgery group (68.6%; p < 0.001). Early decompression surgery produced better neurological recovery; however, an improvement of >4 in the MMT score was achieved in 80% of cases with late decompression.

Indirect Decompression Using Lateral Lumbar Interbody Fusion for Restenosis after an Initial Decompression Surgery

Study Design

Retrospective comparative study.

Purpose

We compared clinical and radiographical outcomes after lumbar decompression revision surgery for restenosis by lateral lumbar interbody fusion (LLIF) and posterior lumbar interbody fusion (PLIF).

Overview of Literature

Indirect lumbar decompression with LLIF was used to treat degenerative lumbar diseases requiring neural decompression. However, only a few studies have focused on the effectiveness of this technique for restenosis after lumbar decompression.

Methods

We retrospectively investigated 52 cases involving lumbar interbody fusions for restenosis with spondylolisthesis after lumbar decompressions; these cases consisted of 15 patients who underwent indirect decompression with LLIF and posterior fixation and 37 patients who underwent the same procedure with PLIF. We compared Japanese Orthopaedic Association (JOA) scores and perioperative complications between groups. The cross-sectional areas of the thecal sac on magnetic resonance imaging were measured before, immediately after, and 2 years after surgery. We conducted statistical analyses using unpaired t -test and Fisher’s exact tests, and a p-value <0.05 was considered statistically significant.

Results

The operative time was significantly shorter in the LLIF group than in the PLIF group (115.3±33.6 min vs. 186.2±34.2 min, respectively; p<0.001). In addition, the intraoperative blood loss was significantly lower in the LLIF group than in the PLIF group (58.2±32.7 mL vs. 303.2±140.1 mL, respectively; p<0.001). We found two cases of transient lateral thigh weakness (13.3%) in the LLIF group and five cases of incidental durotomy, one case of deep infection, and one case of neurological deterioration in the PLIF group—resulting in a higher complication incidence (18.9%), although it did not reach (p=0.63). The JOA scores improved significantly in both groups.

Conclusions

Indirect decompression using LLIF provided acceptable clinical and radiographical outcomes in patients with restenosis with spondylolisthesis after lumbar decompression; no revision-surgery-specific complications were found. Our results suggest that LLIF is a safe and minimally invasive procedure for revision surgery.

The Prevalence and Risk Factors for S2 Alar-Iliac Screw Loosening with a Minimum 2-Year Follow-up

STUDY DESIGN

A retrospective cohort study.

PURPOSE

The purpose of this study was to investigate the prevalence and risk factors for S2 alar-iliac (SAI) screw loosening following lumbosacral fixation, with a minimum 2-year follow-up.

OVERVIEW OF LITERATURE

Although SAI screws allow surgeons to perform lumbosacral fixation with a low profile and enhanced biomechanical strength, screw loosening following surgery can occur in some cases. However, few studies have investigated the prevalence and risk factors for SAI screw loosening.

METHODS

This retrospective study included 35 patients (mean age, 72.8±8.0 years; male, 10; female, 25) who underwent lumbosacral fixation using SAI screws with at least 2 years of follow-up. SAI screw loosening and L5-S bony fusion were assessed using computed tomography. The period for which the screws appeared loose and the risk factors for SAI screw loosening were investigated 2 years after surgery.

RESULTS

A total of 70 SAI screws and 70 S1 pedicle screws were inserted. Loosening was observed 0.5, 1, and 2 years after surgery in 17 (24.3%), 35 (50.0%), and 35 (50.0%) SAI screws, respectively. Bony fusion rate at L5-S was significantly lower in patients with SAI screw loosening than in those without screw loosening (65.0% vs. 93.3%, p =0.048). The score for SAI screw contact with the iliac cortical bone and the bony fusion rate at L5-S were significantly lower in the loosening group than in the non-loosening group (1.8±0.5 vs. 2.2±0.3, p <0.001, respectively). Postoperative pelvic incidence-lumbar lordosis was significantly higher in the loosening group than in the non-loosening group (7.9°±15.4° vs. 0.5°±8.7°, p =0.02, respectively).

CONCLUSIONS

SAI screw loosening is closely correlated with pseudoarthrosis at L5-S. Appropriate screw insertion and optimal lumbar lordosis restoration are important to prevent postoperative complications related to SAI screws.

A candidate-SNP retrospective cohort study for fracture risk in Japanese Thoroughbred racehorses

Fractures are medical conditions that compromise the athletic potential of horses and/or the safety of jockeys. Therefore, the reduction of fracture risk is an important horse and human welfare issue. The present study used molecular genetic approaches to determine the effect of genetic risk for fracture at four candidate SNPs spanning the myostatin (MSTN) gene on horse chromosome 18. Among the 3706 Japanese Thoroughbred racehorses, 1089 (29.4%) had experienced fractures in their athletic life, indicating the common occurrence of this injury in Thoroughbreds. In the case/control association study, fractures of the carpus (carpal bones and distal radius) were statistically associated with g.65809482T/C (P = 1.17 x 10^-8 ), g.65868604G/T (P = 2.66 x 10^-9 ), and g.66493737C/T (P = 6.41 x 10^-8 ). In the retrospective cohort study using 1710 racehorses born in 2000, the relative risk (RR) was highest for male horses at g.65868604G/T, based on the dominant allele risk model (RR = 2.251, 95% confidence interval 1.407-3.604, P = 0.00041), and for female horses at g.65868604G/T, based on the recessive allele risk model (RR = 2.313, 95% confidence interval 1.380-3.877, P = 0.00163). Considering the association of these SNPs with racing performance traits such as speed, these genotypes may affect the occurrence of carpus fractures in Japanese Thoroughbred racehorses as a consequence of the non-genetic influence of the genotype on the distance and/or intensity of racing and training. The genetic information presented here may contribute to the development of strategic training programs and racing plans for racehorses that improve their health and welfare.

Changes in Sagittal Alignment Following Short-Level Lumbar Interbody Fusion: Comparison between Posterior and Lateral Lumbar Interbody Fusions

Study Design

Retrospective case-control study.

Purpose

We aimed to compare radiologic outcomes between posterior (PLIF) and lateral lumbar interbody fusion (LLIF) in short-level spinal fusion surgeries.

Overview of Literature

Although LLIF enables surgeons to insert large lordotic cages, it is unknown whether LLIF more effectively corrects local and global sagittal alignments compared with PLIF in short-level spinal fusion surgeries.

Methods

Radiographic data acquired from patients with lumbar interbody fusion (≤3 levels) using PLIF or LLIF for degenerative lumbar diseases were analyzed. The following radiographic parameters were evaluated preoperatively and at 2 years postoperatively: segmental lordotic angle, disk height, lumbar lordosis (LL), pelvic tilt (PT), C7 sagittal vertical axis, and thoracic kyphosis (TK).

Results

In total, 144 patients with PLIF (193 fused levels) and 101 with LLIF (159 fused levels) were included. Patients’ backgrounds and preoperative radiographic parameters for any level of fusion did not differ significantly between PLIF and LLIF procedures. The LLIF group exhibited significantly greater changes at 1-level fusion compared to the PLIF group in the parameters of segmental lordotic angle (5.1°±5.8° vs. 2.1°±5.0°, p<0.001), disk height (4.2±2.3 mm vs. 2.2±2.0 mm, p<0.001), LL (7.8°±7.6° vs. 3.9°±8.6°, p=0.004), and PI–LL (−6.9°±6.8° vs. −3.6°±10.1°, p=0.03). While, a similar trend was observed regarding 2-level fusion, significantly greater changes were only observed in LL (12.1°±11.1° vs. 4.2°±9.1°, p=0.047) and PI–LL (−11.2°±11.3° vs. −3.0°±9.3°, p=0.043), PT (−6.4°±4.9° vs. −2.5°±5.3°, p=0.049) and TK (7.8°±11.8° vs. −0.3°±9.7°, p=0.047) in the LLIF group at 3-level fusion.

Conclusions

LLIF provides significantly better local sagittal alignment than PLIF in 1- or 2-level fusion cases and improves spinopelvic alignment and local alignment for 3-level fusion cases. Thus, LLIF was demonstrated to be a useful lumbar interbody fusion technique, constituting a powerful tool for achieving sagittal realignment with minimal surgical invasiveness.

Factors Affecting Postoperative Sagittal Alignment after Lateral Lumbar Interbody Fusion in Adult Spinal Deformity: Posterior Osteotomy, Anterior Longitudinal Ligament Rupture, and Endplate Injury

Study Design

Prospective cohort study.

Purpose

To identify factors that affect sagittal alignment correction in lateral lumbar interbody fusion (LIF) surgery for adult spinal deformity (ASD) and to investigate the degree of correction in each condition.

Overview of Literature

LIF is a useful procedure for ASD, but the degree of correction can be affected by posterior osteotomy, intraoperative endplate injury, or anterior longitudinal ligament (ALL) rupture.

Methods

Radiographical data for 30 patients who underwent LIF for ASD were examined prospectively. All underwent two-stage surgery (LIF followed by posterior fixation). Radiographical parameters were measured preoperatively, after LIF, and after posterior fixation; these included the segmental lordotic angle, lumbar lordosis (LL), and other sagittal alignment factors.

Results

LL was corrected from 16.5°±16.7° preoperatively to 33.4°±13.8° after LIF (p <0.001) and then to 52.1°±7.9° following posterior fixation (p <0.001). At levels where Schwab grade 2 osteotomy was performed, the acquired segmental lordotic angles from the preoperative value to after posterior fixation and from after LIF to after posterior fixation were 19.5°±9.2° and 9.9°±3.9°, respectively. On average, 12.4° more was added than in cases without osteotomy. Endplate injury was identified at 21 levels (19.4%) after LIF, with a mean loss of 3.4° in the acquired segmental lordotic angle (5.3°±8.4° and 1.9°±5.9° without and with endplate injury, respectively). ALL rupture was identified at seven levels (6.5%), and on average 19.3° more was added in these cases between the preoperative and postoperative values than in cases without ALL rupture.

Conclusions

LIF provides adequate sagittal alignment restoration for ASD, but the degree of correction is affected by grade 2 osteotomy, intraoperative endplate injury, and ALL rupture.

Comparative Radiographic Outcomes of Lateral and Posterior Lumbar Interbody Fusion in the Treatment of Degenerative Lumbar Kyphosis

STUDY DESIGN

Retrospective case-control study.

PURPOSE

To compare surgical invasiveness and radiological outcomes between posterior lumbar interbody fusion (PLIF) and lateral lumbar interbody fusion (LLIF) for degenerative lumbar kyphosis.

OVERVIEW OF LITERATURE

LLIF is a minimally invasive interbody fusion technique; however, few reports compared the clinical outcomes of conventional PLIF and LLIF for degenerative lumbar kyphosis.

METHODS

Radiographic data for patients who have undergone lumbar interbody fusion (≥3 levels) using PLIF or LLIF for degenerative lumbar kyphosis (lumbar lordosis [LL] <20°) were retrospectively examined. The following radiographic parameters were retrospectively evaluated preoperatively and 2 years postoperatively: segmental lordotic angle, LL, pelvic tilt (PT), pelvic incidence (PI), C7 sagittal vertical axis, and T1 pelvic angle.

RESULTS

Nineteen consecutive cases with PLIF and 27 cases with LLIF were included. There were no significant differences in patients' backgrounds or preoperative radiographic parameters between the PLIF and the LLIF groups. The mean fusion level was 5.5±2.5 levels and 5.8±2.5 levels in the PLIF and LLIF groups, respectively (p=0.69). Although there was no significant difference in surgical times (p=0.58), the estimated blood loss was significantly greater in the PLIF group (p<0.001). Two years postoperatively, comparing the PLIF and LLIF groups, the segmental lordotic angle achieved (7.4°±7.6° and 10.6°±9.4°, respectively; p=0.03), LL (27.8°±13.9° and 39.2°±12.7°, respectively; p=0.006), PI-LL (19.8°±14.8° and 3.1°±17.5°, respectively; p=0.002), and PT (22.6°±7.1° and 14.2°±13.9°, respectively; p=0.02) were significantly better in the LLIF group.

CONCLUSIONS

LLIF provided significantly better sagittal alignment restoration in the context of degenerative lumbar kyphosis, with less blood loss.

Glycan sulfation patterns define autophagy flux at axon tip via PTPRσ-cortactin axis

Chondroitin sulfate (CS) and heparan sulfate (HS) are glycosaminoglycans that both bind the receptor-type protein tyrosine phosphatase PTPRσ, affecting axonal regeneration. CS inhibits axonal growth, while HS promotes it. Here, we have prepared a library of HS octasaccharides and, together with synthetic CS oligomers, we found that PTPRσ preferentially interacts with CS-E-a rare sulfation pattern in natural CS-and most HS oligomers bearing sulfate and sulfamate groups. Consequently, short and long stretches of natural CS and HS, respectively, bind to PTPRσ. CS activates PTPRσ, which dephosphorylates cortactin-herein identified as a new PTPRσ substrate-and disrupts autophagy flux at the autophagosome-lysosome fusion step. Such disruption is required and sufficient for dystrophic endball formation and inhibition of axonal regeneration. Therefore, sulfation patterns determine the length of the glycosaminoglycan segment that bind to PTPRσ and define the fate of axonal regeneration through a mechanism involving PTPRσ, cortactin and autophagy.

Unplanned Second-Stage Decompression for Neurological Deterioration Caused by Central Canal Stenosis after Indirect Lumbar Decompression Surgery

Study Design

Prospective cohort study.

Purpose

This study aimed to identify risk factors for unplanned second-stage decompression for postoperative neurological deficit after indirect decompression using lateral lumbar interbody fusion (LLIF) with posterior fixation.

Overview of Literature

Indirect lumbar decompression with LLIF has been used as a minimally invasive alternative to direct decompression to treat degenerative lumbar diseases requiring neural decompression. However, evidence on the prevalence of neurological deficits caused by spinal canal stenosis after indirect decompression is limited.

Methods

This study included 158 patients (mean age, 71.13±7.98 years; male/female ratio, 67/91) who underwent indirect decompression with LLIF and posterior fixation. Indirect decompression was performed at 271 levels (mean level, 1.71±0.97). Logistic regression analysis was used to identify the risk factors for postoperative neurological deficits. The variables included were age, sex, body mass index, presence of primary diseases, diabetes mellitus, preoperative motor deficit, levels operated on, preoperative severity of lumbar stenosis, and preoperative Japanese Orthopedic Association (JOA) score.

Results

Postoperative neurological deficit due to spinal canal stenosis occurred in three patients (1.9%). Spinal stenosis due to hemodialysis (p<0.001), ligament ossification (p<0.001), presence of preoperative motor paralysis (p<0.001), low JOA score (p=0.004), and severe canal stenosis (p=0.02) were significantly more frequent in the paralysis group.

Conclusions

Severe preoperative canal stenosis and neurological deficit were identified as risk factors for postoperative neurological deterioration caused by spinal canal stenosis. Additionally, uncommon diseases, such as spinal stenosis due to hemodialysis and ligament ossification, increased the risk of postoperative neurological deficit; therefore, in such cases, indirect decompression is contraindicated.

Development of a tracer-containing compact-toroid injection system

The accumulation and behavior of impurities is one of the most important subjects in the development of magnetically confined fusion reactors because impurities can potentially cause cooling and worsen the confinement of the hot core plasma. Tracer-encapsulated solid pellets (TESPELs) have demonstrated some results for impurity injection for fusion-reactor plasma studies [N. Tamura et al., J. Phys. Conf. Ser. 823, 012003 (2017)]. However, the TESPEL technique has several shortcomings, for example, the penetration depth and the amounts of tracer impurities. In the present study, we have developed a tracer-containing, compact-toroid (TCCT) injection system that utilizes a magnetized coaxial plasma gun (MCPG). The discharge current through the MCPG sputters and ionizes the electrode material, and the Lorenz self-force accelerates it as a plasmoid. The MCPG easily accelerates a magnetized plasmoid to speeds greater than the ion thermal velocity of several tens of kilometers per second. The accelerated and ejected plasmoid that contains the tracer ions is itself a warm, ionized plasma. Therefore, a TCCT can potentially be injected into the core region of a target plasma with less adverse effect.

Nonunion of Transpsoas Lateral Lumbar Interbody Fusion Using an Allograft: Clinical Assessment and Risk Factors

Introduction

This retrospective study was performed to evaluate the clinical influence of - and to identify the risk factors for nonunion of transpsoas lateral lumbar interbody fusion (LLIF) with use of allograft.

Methods

Sixty-three patients who underwent transpsoas LLIF (69.8 ± 8.9 years, 21 males and 42 females, 125 segments) were followed for a minimum 2 years postoperatively. For all LLIF segments, polyetheretherketone (PEEK) cages packed with allogenic bone were applied with supplemental bilateral pedicle screws (PSs). Bone bridge formation was evaluated by computed tomography (CT) 2 years postoperative, and a segment without any bridge formation was determined to be a nonunion. Sixty-one participants (96.8%) were classified into two groups for clinical evacuation: Group N that contained one or more nonunion segments and Group F that contained no nonunion segment. Visual analogue scales (VAS) scores and the effective rates of the five domains of the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) were compared between Groups N and F. The risk factors for nonunion were determined by univariate and multivariate analyses.

Results

Twenty segments (16%) were diagnosed as nonunion. There were no significant differences in all VAS scores, and the ratio of effective cases in all domains of JOABPEQ between Group N (n = 14) and F (n = 47). Multivariate analysis identified percutaneous PS (PPS) usage (odds ratio [OR]: 3.14, 95% confidence interval: 1.13-8.68, p = 0.028) as a positive risk factor for nonunion.

Conclusions

We should be aware of the higher nonunion rate in the LLIF segments supplemented with PPS, though nonunion does not affect significantly clinical outcomes at 2 years postoperative.