The Impact of Reduced Skeletal Muscle Mass on Patients with Knee Osteoarthritis.

Although several studies have suggested a possible association between sarcopenia and knee osteoarthritis (OA) in the elderly, there remains no definitive evidence. Recently, however, the serum creatinine/cystatin C ratio (sarcopenia index: SI) was reported to correlate with skeletal muscle mass. The present retrospective study therefore investigated the impact of reduced skeletal muscle mass on advanced knee OA using SI. In 55 individuals scheduled for knee osteotomy or knee arthroplasty, correlations between SI and patient-reported outcomes such as the Knee Society Score (KSS), Knee Injury and Osteoarthritis Outcome Score (KOOS), and Oxford Knee Score (OKS) were explored. Significant associations were found between SI and the KSS functional activity score (ß=0.37; p=0.022), KOOS subscale for activities of daily living (ß=0.42; p=0.0096), and OKS (ß=0.42; p=0.0095). This study underscores the role of reduced muscle mass in functional outcomes and introduces SI as a valuable marker for assessing muscle loss in knee OA patients.

The difficulty of nuclear emergency prevention measures during natural disasters: ongoing challenges in Japan.

It is crucial to anticipate nuclear emergency scenarios and implement effective measures. Japan's climate and topography make it vulnerable to natural disasters; thus, it is necessary to address compounding and cascading disaster scenarios involving the simultaneous occurrence of natural and nuclear disasters. On 1 January 2024, an earthquake hit the Noto region of Ishikawa Prefecture, resulting in damage to the area around the Shika Nuclear Power Plant, located 90 km from the epicenter. This earthquake revealed that, in the event of a complex disaster, it is possible that residents living within 30 km of the Shika Nuclear Power Plant will be completely unprepared for a nuclear disaster. In the event of a complex disaster, it is crucial to implement appropriate countermeasures while balancing responses to both nuclear and natural disasters and optimizing radiation disaster prevention measures.

Successful Treatment of Atypical Femoral Fracture with Bowed Femur Using Contralateral Intramedullary Nail Combined with Early Daily Teriparatide.

We report a case of atypical femoral fracture achieving early fracture union with combination therapy comprising contralateral nail and immediate teriparatide injection. Fracture union of atypical fractures is often delayed due to bowing deformity and bone metabolic disorders. Combination treatment that takes both problems into consideration represents a useful treatment option for atypical femoral fracture.

Enhancement of synaptic responses in ascending interneurones following acquisition of social dominance in crayfish.

When crayfish have attained dominant status after agonistic bouts, their avoidance reaction to mechanical stimulation of the tailfan changes from a dart to a turn response. Ascending interneurones originating in the terminal ganglion receive sensory inputs from the tailfan and they affect spike activity of both uropod and abdominal postural motor neurones, which coordinates the uropod and abdominal postural movements. Despite the varying output effects of ascending interneurones, the synaptic responses of all interneurones to sensory stimulation were enhanced when they acquired a dominant state. The number of spikes increased as did a sustained membrane depolarizations. Regardless of social status, the output effects on the uropod motor neurones of all interneurones except VE-1 remained unchanged. VE-1 mainly inhibited the uropod opener motor neurones in naive animals, but tended to excite them in dominant animals. Synaptic enhancement of the sensory response of ascending interneurones was also observed in naive animals treated with bath-applied serotonin. However, subordinate animals or naive animals treated with octopamine had no noticeable effect on the synaptic response of their ascending interneurones to sensory stimulation. Thus, enhancement of the synaptic response is a specific neural event that occurs when crayfish attain social dominance and it is mediated by serotonin.

Aversive operant conditioning alters the phototactic orientation of the marbled crayfish.

Aversive learning was applied to affect the phototactic behaviour of the marbled crayfish. Animals initially showed negative phototaxis to white light and positive taxis to blue light. Using an aversive learning paradigm, we investigated the plasticity of innate behaviour following operant conditioning. The initial rate of choosing a blue-lit exit was analysed by a dual choice experiment between blue-lit and white-lit exits in pre-test conditions. During training, electrical shocks were applied to the animals when they oriented to the blue-lit exit. Memory tests were given to analyse the orientation rate to the blue-lit exit in trials 1 and 24 h after training and these rates were compared with the pre-test. In general, animals avoided the blue-lit exit in the memory tests. When training was carried out three times, the long-term memory was retained for at least 48 h, although a single bout of training was also enough to form a long-term memory. Cooling animals at 4°C or injection of cycloheximide immediately after training altered the formation of long-term memory, but had no effect on short-term memory formation. Administration of the adenylate cyclase inhibitor SQ22536, the PKA inhibitor H89 or the CREB inhibitor KG-501 immediately after training also blocked the formation of long-term memory, but had no effect on short-term memory formation. Thus, our pharmacological behavioural analyses showed that new protein synthesis was necessary to form long-term memories and that the cAMP/PKA/CREB pathway is the main signal cascade for long-term memory formation in the marbled crayfish.

Proximal junctional fracture and kyphosis after long spinopelvic corrective fixation for adult spinal deformity.

BACKGROUND: Proximal junctional fractures (PJFx) are the main cause for proximal junctional kyphosis (PJK), a complication of adult spinal deformity surgery. This study investigated risk factors for PJFx when performing long spinopelvic corrective fixation with lateral interbody fusion from T9 to ilium. METHODS: This was a retrospective study of 43 patients with a minimum follow-up of 2 years. Radiographic measurements including thoracic kyphosis (TK), sagittal vertical axis (SVA), T1 pelvic angle (TPA), proximal junctional angle (PJA), lumbar lordosis (LL), lower LL, and pelvic tilt were measured preoperatively, one-month postoperatively, and at final follow up. TK and LL were also measured in a fulcrum backward-bending position preoperatively. RESULTS: At final follow-up, PJK was found in 30/43 patients (69.8%); 20.9% of the cases had PJFx (9 patients). TPA (preoperative, and one-month postoperative) was significantly higher in the PJFx group than in the other groups. The differences in TPA, TK, and PJA between preoperative and one-month postoperative measurements in the PJFx group were significantly higher than those in the other groups. At final follow up, SVA was significantly higher in the PJFx group than in the "PJK without PJFx" group. TPA and TK were significantly higher in the PJFx group than in the other groups. PJA was significantly different between all groups. CONCLUSION: Preoperative large TPA was the only risk factor for PJFx. Preoperative flexibility of the thoracolumbar spine and overcorrection of sagittal deformity were not related to PJFx or PJK.

Activities of daily living and patient satisfaction after long fusion for adult spinal deformity: a retrospective study.

PURPOSE: Spinal instrumented arthrodesis improves health-related quality of life (HRQOL), although mobility is impaired. This study evaluates activities of daily livings after thoracolumbosacroiliac arthrodesis for adult spinal deformity and patient satisfaction. METHODS: Fifty patients who underwent surgery filled self-administered questionnaires (1-year preoperative and postoperative conditions), and 36 patients (3 men and 33 women; mean age 71.4 years) participated in the study. Twenty-five activities, including weeding, snow shoveling, toilet activities, and sleeping postures, were examined. Spinal alignment with Scoliosis Research Society (SRS)-Schwab classification, HRQOL with SRS-22, complications, and patient satisfaction were evaluated. Pre- and postoperative conditions were statistically compared. RESULTS: Spinal alignment improved postoperatively. Comparison data revealed that strenuous activities, such as weeding and farm work, significantly deteriorated postoperatively in 42.1-87.5% patients. Other basic activities, excluding Western toilet usage, sleeping supine, laundry and kitchen chores, and changing jacket/pants, also significantly deteriorated in 21-88% patients. Only activities such as sleeping supine, standing upright, vacuuming, doing laundry, and reaching for objects placed at heights became possible with significant difference postoperatively among activities that could not be performed preoperatively. Light activities were continued, but strenuous activities were restricted. Nevertheless, the patient satisfaction rate was 70%. Six patients exhibited complications; however, none were dissatisfied with surgery outcomes. Instrumentation or proximal junctional failures were associated with at least one strenuous work activity. CONCLUSIONS: Thoracolumbosacroiliac arthrodesis does not always improve activities postoperatively. Therefore, surgical indication for patients who continue activities preoperatively should be carefully decided. LEVEL OF EVIDENCE: Level 3. These slides can be retrieved under Electronic Supplementary Material.

A case report of revision occipital-cervical fusion after atlanto-axial instrumentation failure for neurofibromatosis type I.

BACKGROUND: Neurofibromatosis type 1 is an autosomal dominant genetic disease with characteristic café-au-lait spots, neurofibroma, and dystrophic changes in the bones. However, complications involving atlanto-axial dislocation are rare. CASE PRESENTATION: We report a case of neurofibromatosis with atlanto-axial dislocation. The chief complaints were numbness of the upper limb and gait disturbance. We performed short fusion using the Brooks method. However, recurrence of the dislocation was found after 5 months recovery, and the patient underwent posterior fusion from the occipital bone to C4. Thereafter, she had a good postoperative course. CONCLUSIONS: Neurofibromatosis patients often exhibit a low bone mineral density because of dystrophic changes, and are prone to fragile bones. In the present case, the use of long fusion at the first surgery may have helped to form a strong fusion of fragile bone.

Comparison of patients with diagnosed and suspected sacral insufficiency fractures.

BACKGROUND: Patients with sacral insufficiency fractures can have a range of symptoms, and because these fractures are difficult to detect using plain radiographs, it can be tough to make a definitive diagnosis of fracture early after injury. The aim of this study was to compare the diagnosis and treatment of patients with known sacral insufficiency fractures to those with suspected insufficiency fractures to clarify the features of sacral insufficiency fractures. METHODS: We compared patients with sacral insufficiency fractures (S group) to those with suspected insufficiency fractures (N group) using demographic data, symptoms, time to definitive diagnosis, radiological methods, and treatments. RESULTS: Patients in the S group were older than those in the N group (p = 0.0042) and showed less localized sacral pain (p = 0.0042). Almost all of the patients in the S group (74%) required magnetic resonance imaging for definitive diagnosis. CONCLUSIONS: Sacral insufficiency fractures should not be diagnosed based on the site of pain or using plain radiographs. Patient age and magnetic resonance imaging are more informative to obtain a definitive diagnosis of sacral insufficiency fractures.

Limaprost or Pregabalin: Preoperative and Postoperative Medication for Pain due to Lumbar Spinal Stenosis.

PURPOSE: We aimed to evaluate the incidence of (and risk factors for) postoperative pregabalin and/or limaprost to treat persistent numbness and/or pain of the lower extremities after lumbar spinal stenosis (LSS) surgery. METHODS: Medical records of 329 patients (168 men, 161 women; average age 70 years) were retrospectively reviewed for data on the duration of LSS diagnosis; LSS disease; preoperative medication (limaprost, pregabalin, or combined limaprost/pregabalin; duration); symptoms; preoperative/postoperative intermittent claudication (IC); operation type; and postoperative medication and period. RESULTS: Limaprost, pregabalin, and combined limaprost/pregabalin were prescribed preoperatively for 43%, 7%, and 5% of patients, respectively. At an average of 21 months postoperatively, limaprost, pregabalin, and combined therapy were prescribed in 11%, 8%, 4% of patients, respectively. Medication requirement was significantly lower postoperatively than preoperatively (P < 0.0001). Significant risk factors for required postoperative medication were required preoperative medication (odds ratio [OR] 3.088, 95% confidence interval [CI] 1.679 to 5.681]; postoperative period (OR 1.063, 95% CI 1.031 to 1.096); and postoperative IC (OR 3.868, 95% CI 1.481 to 10.103). A negative impact from postoperative medication was seen in patients who had undergone decompression surgery (OR 0.589, 95% CI 0.377 to 0.918). CONCLUSIONS: Overall, 23% of LSS patients required medication for pain and/or numbness at 21 months postoperatively. Significant factors portending required postoperative medication were preoperative medication, longer postoperative period, and postoperative IC. A negative influence from postoperative medication was seen in patients who had undergone decompression surgery without fusion.

Diminished neutralizing activity against the XBB1.5 strain in 55.9% of individuals post 6 months COVID-19 mRNA booster vaccination: insights from a pseudovirus assay on 1,353 participants in the Fukushima vaccination community survey, Japan.

This study investigates the neutralizing activity against the XBB1.5 variant and the ancestral strain in a population post-bivalent vaccination using a pseudo virus assay validated with authentic virus assay. While bivalent booster vaccination and past infections enhanced neutralization against the XBB 1.5 strain, individuals with comorbidities showed reduced responses. The study suggests the need for continuous vaccine updates to address emerging SARS-CoV-2 variants and highlights the importance of monitoring real-world immune responses.

Categorization of disaster-related deaths in Minamisoma city after the Fukushima nuclear disaster using clustering analysis.

The medical situation during disasters often differs from that at usual times. Disasters can lead to significant mortality that can be difficult to monitor. The types of disaster-related deaths are largely unknown. In this study, we conducted a survey to categorize the disaster-related deaths caused by a radiation disaster. A total of 520 people living in Minamisoma City, Fukushima Prefecture, at the time of the Fukushima Daiichi Nuclear Power Plant accident, who were certified to have died due to disaster-related causes were surveyed. We divided the participants into those who were at home at the time of the earthquake and those who were in hospitals or facilities when the disaster struck and conducted a hierarchical cluster analysis of the two groups. Disaster-related deaths could be divided into seven groups for those who were at home at the time of the disaster and five groups for those who were in hospitals or facilities at the time of the disaster. Each group showed different characteristics, such as "the group with disabilities," "the group receiving care," and "the group with depression," and it became evident that not only uniform post-disaster support, but support tailored to the characteristics of each group is necessary.

Modeling and predicting individual variation in COVID-19 vaccine-elicited antibody response in the general population.

As we learned during the COVID-19 pandemic, vaccines are one of the most important tools in infectious disease control. To date, an unprecedentedly large volume of high-quality data on COVID-19 vaccinations have been accumulated. For preparedness in future pandemics beyond COVID-19, these valuable datasets should be analyzed to best shape an effective vaccination strategy. We are collecting longitudinal data from a community-based cohort in Fukushima, Japan, that consists of 2,407 individuals who underwent serum sampling two or three times after a two-dose vaccination with either BNT162b2 or mRNA-1273. Using the individually reconstructed time courses of the vaccine-elicited antibody response based on mathematical modeling, we first identified basic demographic and health information that contributed to the main features of the antibody dynamics, i.e., the peak, the duration, and the area under the curve. We showed that these three features of antibody dynamics were partially explained by underlying medical conditions, adverse reactions to vaccinations, and medications, consistent with the findings of previous studies. We then applied to these factors a recently proposed computational method to optimally fit an "antibody score", which resulted in an integer-based score that can be used as a basis for identifying individuals with higher or lower antibody titers from basic demographic and health information. The score can be easily calculated by individuals themselves or by medical practitioners. Although the sensitivity of this score is currently not very high, in the future, as more data become available, it has the potential to identify vulnerable populations and encourage them to get booster vaccinations. Our mathematical model can be extended to any kind of vaccination and therefore can form a basis for policy decisions regarding the distribution of booster vaccines to strengthen immunity in future pandemics.

Posterior-approach vertebral replacement with rectangular parallelepiped cages (PAVREC) for the treatment of osteoporotic vertebral collapse with neurological deficits.

STUDY DESIGN: A retrospective clinical study. OBJECTIVE: To assess the efficacy of a new spinal reconstruction technique (posterior-approach vertebral replacement with rectangular parallelepiped cages: PAVREC) for the treatment of osteoporotic late vertebral collapse with neurological deficits. SUMMARY OF BACKGROUND DATA: Poor bone quality and medically complicated situations obfuscate precise treatment for paraplegia caused by osteoporotic vertebral collapse. Recently, posterior-approach corpectomy and replacement with a cylindrical cage have been proposed. However, postoperative cage subsidence and kyphosis progression frequently occurs. METHODS: Surgical invasiveness, perioperative complications, and clinical and radiographic outcomes in a total of 19 consecutive patients with osteoporosis (7 men and 12 women; mean age, 75 y) who underwent PAVREC with a mean follow-up period of 45.6 months (range, 16-79 mo) were reviewed. The affected vertebral levels ranged from T12-L4. The mean bone mineral density of the femoral neck was 0.611±0.077 g/cm(2) (mean±SD). RESULTS: Mean operative time was 261 minutes (range, 155-326 min). Mean blood loss was 664 mL (range, 197-1595 mL). There were no reported surgical complications. Neurological deficits evaluated with the Frankel grading score improved >1 grade after surgery in all patients. Mean preoperative visual analog scale scores for back or leg pain (7.2; range, 6-9) significantly improved after surgery (1.4; range, 0-2) (P<0.05). Local kyphosis improved from a mean of 24.6 degrees before surgery to a mean of 1.5 degrees after surgery (P< 0.05), and it was maintained at a mean of 2.5 degrees at the final follow-up. Although screw loosening, cage subsidence, and subsequent vertebral fracture were seen in several cases, no additional surgeries were needed. Solid bony fusion was confirmed in all cases. CONCLUSIONS: PAVREC provided a satisfactory clinical and radiologic outcome without severe complications. This procedure can be a treatment option for osteoporotic vertebral collapse and an alternative to an anterior-approach or single posterior-approach reconstruction with a cylindrical cage.

Surgical technique of spine-shortening vertebral osteotomy for adult tethered cord syndrome: a case report and review of the literature.

BACKGROUND: Miyakoshi et al. reported three cases of tethered cord syndrome treated by spine-shortening vertebral osteotomy, which provided relief of the patients' symptoms with no complications. Although the details of these cases were described in a previous report, the surgical technique was not thoroughly explained. In the present report, we describe the details of our procedure with reference to a fourth case. CASE PRESENTATION: A 47-year-old Asian woman was admitted to our hospital with a 1-year history of worsening leg numbness and urinary dysfunction. Magnetic resonance imaging revealed a low-lying conus medullaris extending to the level of S2 and surrounded by fat tissue at that level. We diagnosed her condition as adult tethered cord syndrome, and spine-shortening vertebral osteotomy was planned. The target level for the osteotomy was L2. Bilateral pedicle screw implants were placed at L1 and L3 using an anterior-posterior image intensifier. In this procedure, it is essential to use monoaxial screws inserted exactly parallel to the rostral endplates of each vertebral body; this ensures appropriate alignment between the L1 caudal endplate and the L2 osteotomy surface. The upper one-third of the lamina of L2 was resected, and the bilateral two-thirds of the pedicle of L2 was removed with a surgical air drill. After exposure of the lateral side of the L1-2 disc, discectomy was performed with a knife and curette. Following complete discectomy of L1-2, the upper vertebral body of L2 was removed with a surgical air drill. After complete removal of the vertebral body, a straight rod was connected to two screws and applied pressure between the screws. Two polyethylene tapes were applied to the L2 lamina and bilateral rods. CONCLUSION: Spine-shortening osteotomy that preserves the caudal one-third of the pedicle and lamina with one-above and one-below instrumentation successfully reduced the spinal cord tension without causing neural damage.

Why Do They Not Come Home? Three Cases of Fukushima Nuclear Accident Evacuees.

Many people wish to return to where they used to live after evacuation due to disaster. After the Fukushima nuclear accident in 2011, many residents were forced to evacuate due to concerns about radiation. Subsequently, the evacuation order was lifted, and the government promoted a return policy. However, it has been reported that a considerable number of residents living in evacuation sites or other areas wish to return but are unable to do so. Here, we report three cases of Japanese men and one woman who evacuated after the 2011 nuclear accident in Fukushima. These cases reveal the rapid aging of residents and their health issues. These issues suggest that enhancing medical supply systems and access to medical care can aid in post-disaster reconstruction and residents' returning.

Idobata-Nagaya: a community housing solution for socially isolated older adults following the great East Japan earthquake.

Introduction: Following the Great East Japan Earthquake, the living environment of socially isolated older adults has become a pressing concern. In response, Nagaya, a collective housing program, was established in Soma City, Fukushima, Japan to address social isolation among older adults and support their long-term health. This study aimed to identify characteristics of individuals in Nagaya and examine the sustainability of this initiative. Methods: We conducted a retrospective analysis of residents who were relocated to Nagaya, emphasizing their characteristics, the continuity of their stay in Nagaya, and their care certification levels, using data up to December 31, 2022. We employed Kaplan-Meier curves to analyze the duration for which residents continued to reside in Nagaya and the time leading up to the requiring care-level certification. Results: Of 65 people who moved to Nagaya after the disaster, 30 people (46.2%) continued to live there, 21 (32.3%) died during their stay, and 14 (21.5%) moved out. The overall duration of occupancy averaged 6.39 years (SD 3.83 years). The proportion of requiring care-level certification occurrences per person-year was 0.0577 for those without care certification and 0.3358 for those with requiring support level at the time of moving in. Conclusion: In summary, Nagaya-style communal housing may offer suitable living environments for older adults with diverse needs during disasters and serve as a valuable tool for developing public policies in aging societies.

Multisite Lifestyle for Older People after the Fukushima Nuclear Disaster.

After the Fukushima nuclear power plant disaster in 2011, the Japanese government implemented a return policy, lifting most evacuation orders in former evacuation areas. Consequently, the return of residents is currently underway. However, it has become common for a large number of residents to carry out multisite living, a lifestyle involving returning to their hometown while maintaining their house at the evacuation site, or living at more than two sites. This report focuses on one aspect of the secondary effects of the nuclear incident, which forced affected residents to adopt a multisite lifestyle. Disasters always have a strong impact, via displacement, on those who are socially vulnerable, such as older people in an ageing society. They need intense support to resume their daily life as it was before the incident. For this report, we interviewed an elderly lady in her 90s, who is executing "multisite living" at evacuation sites, in order to obtain reassurance from neighbours and the local community. Our findings may provide valuable suggestions on how older people can restart their lives with the local community in an ageing society after disasters, which could apply to any kind of disaster preparedness.