Calcitriol ameliorates motor deficits and prolongs survival of Chrne-deficient mouse, a model for congenital myasthenic syndrome, by inducing Rspo2

Signal transduction at the neuromuscular junction (NMJ) is compromised in a diverse array of diseases including congenital myasthenic syndromes (CMS). Germline mutations in CHRNE encoding the acetylcholine receptor (AChR) ε subunit are the most common cause of CMS. An active form of vitamin D, calcitriol, binds to vitamin D receptor (VDR) and regulates gene expressions. We found that calcitriol enhanced MuSK phosphorylation, AChR clustering, and myotube twitching in co-cultured C2C12 myotubes and NSC34 motor neurons. RNA-seq analysis of co-cultured cells showed that calcitriol increased the expressions of Rspo2, Rapsn, and Dusp6. ChIP-seq of VDR revealed that VDR binds to a region approximately 15 ​kbp upstream to Rspo2. Biallelic deletion of the VDR-binding site of Rspo2 by CRISPR/Cas9 in C2C12 myoblasts/myotubes nullified the calcitriol-mediated induction of Rspo2 expression and MuSK phosphorylation. We generated Chrne knockout (Chrne KO) mouse by CRISPR/Cas9. Intraperitoneal administration of calcitriol markedly increased the number of AChR clusters, as well as the area, the intensity, and the number of synaptophysin-positive synaptic vesicles, in Chrne KO mice. In addition, calcitriol ameliorated motor deficits and prolonged survival of Chrne KO mice. In the skeletal muscle, calcitriol increased the gene expressions of Rspo2, Rapsn, and Dusp6. We propose that calcitriol is a potential therapeutic agent for CMS and other diseases with defective neuromuscular signal transmission.

A nationwide multicenter study of the cost effectiveness of five leading drugs for pharmacological management of cervicobrachial symptoms

BACKGROUND

Cervicobrachial pain frequently affects the quality of life (QOL) of the general public and has a significant economic impact on the health care systems of various countries. There are a number of treatment options for this disease, including widely-used drug therapy, but the effectiveness of each option is indeterminate, and there have been no published cost-effectiveness analysis studies so far. This prospective observational study aimed to examine the cost-effectiveness of drug treatment for cervicobrachial symptoms.

METHODS

A 6-month medication regimen for each of five frequently-prescribed drugs for cervicobrachial symptoms was administered to 322 patients at 24 centers in Japan. Outcome measures, including of the EuroQol Group 5D, Short Form-8, and Visual Analog Scale (VAS), were investigated at baseline and every month thereafter. Incremental cost-effectiveness ratios (ICERs) of the drug cost to quality-adjusted life years (QALYs) were calculated. A stratified analysis of patient characteristics was also performed to identify baseline factors potentially affecting cost-effectiveness.

RESULTS

The ICER of entire drug treatment for cervicobrachial symptoms was 7,491,640 yen. Compared with the reference willingness-to-pay, the ICER was assumed to not be cost-effective. A certain number of QALYs were gained during the first 3 months after the treatment intervention, but almost no QALYs were gained during the following 3 months. Stratified analysis showed that cost-effectiveness was extremely low for patients with high baseline VAS and high QOL.

CONCLUSIONS

The available medications for cervicobrachial symptoms did not have excellent cost-effectiveness. Although a certain number of QALYs were gained during the first 3 months after medication, no QALYs were gained in the latter half of the study period, suggesting that it is not advisable to continue the medication needlessly.

LEVEL OF EVIDENCE

II, prospective cohort study.

Patient factors influencing a delay in diagnosis in pediatric spinal cord tumors

The diagnosis of pediatric spinal cord tumor is frequently delayed due to the presence of non-specific symptoms. We investigated the factors influencing the delay between the first symptom presentation and the diagnosis for pediatric spinal cord tumor. We retrospectively analyzed 31 patients of age <20 years (18 men, 13 women) who underwent surgery for spinal cord tumor at a single center during 1998-2018. We extracted the relevant data on patients' symptoms, affected spinal location (cervical: C1-7, thoracic: T1-T12, and lumbosacral: L1-S), and tumor anatomical location (extradural, intradural extramedullary, and intramedullary tumor) that could potentially affect the duration of symptom presentation prior to the diagnosis. The most common symptom presented in the patients was pain (n = 22, 71.0 %). Motor symptoms such as paralysis was associated with early diagnosis (P = 0.039). The duration of symptoms prior to diagnosis was found to be significantly longer in patients with spinal tumor in the lumbar-sacral region than in those with the involvement of the cervical and thoracic regions (2.1 ± 1.7 months vs 13.6 ± 12.1 months; P = 0.006 and 2.9 ± 2.2 months vs 13.6 ± 12.1 months; P = 0.012, respectively). Our study results demonstrated that pain was the most common symptom in the examined patients, although it did not affect the delay in diagnosis, whereas the presentation of motor symptoms was helpful in the diagnosis of pediatric spinal cord tumor and the diagnosis could be delayed in lumbar-sacral spinal tumors.

Factors contributing to neck pain in patients with degenerative cervical myelopathy: A prospective multicenter study

PURPOSE

Although the understanding of the mechanisms of low back pain due to spinopelvic sagittal imbalance has strengthened, the understanding of the mechanisms of neck pain remains insufficient. Thus, this study aimed to identify the factors associated with preoperative and postoperative neck pain in patients with degenerative cervical myelopathy who underwent laminoplasty.

METHODS

In this prospective multicenter study, we prospectively enrolled patients who were scheduled for laminoplasty for degenerative cervical myelopathy. The associations between different variables and the Numerical Pain Rating Scale (NRS) scores for neck pain were investigated using univariate and multiple linear regression models.

RESULTS

In total, 92 patients were included in the current study. The univariate analysis showed that age, sex, cervical lordosis in neutral and extension, and thoracic kyphosis were significantly associated with the preoperative NRS score for neck pain; moreover, preoperative cervical lordosis in extension and range of motion and postoperative cervical lordosis in neutral, flexion, and extension were significantly associated with the postoperative NRS Scale score for neck pain. Stepwise multiple regression analysis showed that the independent factors contributing to preoperative neck pain were preoperative cervical lordosis in extension, sex, and age. The independent preoperative predictor and contributor to postoperative neck pain were preoperative cervical lordosis in extension and postoperative cervical lordosis in extension, respectively.

CONCLUSIONS

Cervical lordosis in extension showed significant association with neck pain in patients with degenerative cervical myelopathy. Therefore, when performing laminoplasty for patients with a low cervical lordosis in extension, attention should be paid to residual postoperative neck pain.

Factors Negatively Influencing Postoperative Improvement After Laminoplasty in Degenerative Cervical Myelopathy

STUDY DESIGN

This was a retrospective study of prospectively collected data.

OBJECTIVE

In this study, we aimed to characterize a population of patients with degenerative cervical myelopathy (DCM) and a history of poor postoperative neurological recovery and to identify risk factors associated with poor neurological recovery after laminoplasty.

SUMMARY OF BACKGROUND DATA

Kyphotic cervical alignment has been considered a relative contraindication to laminoplasty in recent years; hence, laminoplasty has been decreasingly performed for the treatment of DCM in patients with cervical kyphosis. However, the effect of global spinal alignment on postoperative outcomes has not been extensively investigated.

MATERIALS AND METHODS

We prospectively enrolled patients who were scheduled for laminoplasty for DCM. Outcome (at enrollment and 1 y after surgery) and risk factor analyses were performed by comparing the good recovery and poor recovery groups. The Spearman correlation coefficient was used to evaluate the relationships between the recovery rate and the preoperative radiographic factors.

RESULTS

In total, 101 patients completed the 1-year follow-up. Regarding clinical outcomes, the Japanese Orthopedic Association score for the assessment of cervical myelopathy, European Quality of Life-5 Dimensions, and Neck Disability Index scores improved postoperatively. The recovery rate was significantly correlated with the preoperative sagittal vertical axis (SVA). The patients in the poor recovery group were older than those in the good recovery group. Univariate analyses showed that the SVA and T1 pelvic angle were significantly higher in the poor recovery group. Lastly, stepwise logistic regression analysis showed that a higher SVA was an independent predictor of poor recovery after laminoplasty.

CONCLUSIONS

The SVA and T1 pelvic angle were significantly higher in the poor recovery group. A high preoperative SVA is an independent predictor for poor recovery after laminoplasty. Therefore, indications for laminoplasty in elderly DCM patients with a high preoperative SVA should be carefully considered.

LEVEL OF EVIDENCE

Level III.

Differences in the prevalence of locomotive syndrome and osteoporosis in Japanese urban and rural regions: The Kashiwara and Yakumo studies

OBJECTIVES

To clarify whether the prevalence of locomotive syndrome (LS) and osteoporosis differed according to region, gender, and physical functions in Japan.

METHODS

Data were collected in Kashiwara City (urban region) and Yakumo Town (rural region). Totally, 208 participants from the urban region and 782 participants from the rural region were included in this study. LS was assessed using the 25-item Geriatric Locomotive Function Scale and osteoporosis was assessed using a quantitative ultrasound. Physical functions were measured using grip strength and the 3-m timed up-and-go test. Differences between urban and rural regions were investigated using standardized incidence ratio and multivariate analysis.

RESULTS

The prevalence of LS and osteoporosis was 24.5% and 42.8% in the urban region and 10.9% and 28.8% in the rural region, respectively. The standardized incidence ratio of the urban region versus the rural region was 1.80 (95% confidence intervals [CI] = 1.35-2.39) for LS and 1.21 (95% CI = 1.32-2.43) for osteoporosis, showing that the prevalence of LS was significantly higher in the urban region. Multivariate analysis indicated that LS was significantly associated with the urban sample and timed up-and-go was significantly longer in the urban sample.

CONCLUSION

Regional differences may be considered when evaluating LS in health checkups. Understanding the results of this study may help reduce LS prevalence.

Relationship of frequency of participation in a physical checkup and physical fitness in middle-aged and elderly people: the Yakumo study

An annual physical checkup is provided as part of the long-term Yakumo study. The checkup is voluntary and there is variation in the frequency of participation. The aim of this study was to examine relationship of physical fitness with frequency of participation in this checkup. The subjects had all attended at least one annual physical checkup from 2006 to 2018. Data from 1,804 initial checkups were used for analysis. At the checkups, age, gender, height, weight, body mass index (BMI), and bone mineral density (BMD) were recorded, and physical activity was measured. The average number of physical checkups per participant for 13 years was 2.4 (1-13). Daily exercise habits were found to be significantly associated with higher participation in physical checkups. Furthermore, between groups with low (1-5 times; <90th percentile of participants) and high (≥6 times) participation, weight and BMI were significantly higher, and BMD, grip strength, 10-m gait time, back muscle strength, and two-step test were all significantly lower in the group with lower frequency of participation in the checkup. In conclusions, our results show that frequency of participation in a voluntary annual physical checkup is significantly associated with physical fitness in middle-aged and elderly people.

The 5-question Geriatric Locomotive Function Scale predicts postoperative fall risk in patients undergoing surgery for degenerative cervical myelopathy

BACKGROUND

Falling is one of the main reasons for which older adults require nursing care. Locomotive syndrome (LS) predicts the need for nursing care; however, the relationship between falling and LS remains unclarified. This study aimed to determine whether the 5-question Geriatric Locomotive Function Scale (GLFS-5) predicts postoperative fall risk in patients with degenerative cervical myelopathy (DCM).

METHODS

This study is a post hoc analysis of the data from a prospective cohort of patients undergoing surgery for DCM. Participants recorded their falls in a fall diary from the time of study enrollment (baseline) to 1 year postoperatively. Functional assessments were conducted at baseline, hospital admission for surgery, and 1 year postoperatively. Outcome measures included the GLFS-5, Japanese Orthopaedic Association score, Neck Disability Index, EuroQol 5 Dimensions, and 12-Item Short Form Health Survey. Risk factors for falls were investigated, including previous falls, number of medications, and grip strength. Fallers were divided into two categories: all fallers (≥1 falls), and recurrent fallers (≥2 falls). Variables that were significant in univariate analyses were applied in multiple logistic regression models to adjust for confounders.

RESULTS

From the initial group of 168 participants, 159 attended the 1-year follow-up, and 132 fall diaries were retrieved and analyzed. Of these 132 patients, 42 (32%) reported at least one fall, while 25 (19%) reported recurrent falls during the postoperative observation period. The GLFS-5 significantly increased from baseline to admission, and significantly decreased from admission to 1 year postoperatively. In multiple logistic regression analysis, the independent predictors of postoperative recurrent falls were previous falls and a higher baseline GLFS-5. The optimal cut-off value of GLFS-5 for predicting all falls/recurrent falls was 12.

CONCLUSIONS

The GLFS-5 reflected time-dependent functional changes in patients undergoing surgery for DCM. Previous falls and a higher baseline GLFS-5 were independent predictors of postoperative recurrent falls.

Superficial Siderosis With Verrucous Vegetation Around a Dural Defect Confirmed by Intraoperative Ultrasonography

Superficial siderosis (SS) of the central nervous system (CNS) is a rare disease caused by repeated hemorrhages in the subarachnoid space. We describe surgical treatment of an SS case in which a dural defect with verrucous vegetation in the spinal canal was detected by intraoperative ultrasonography (US). After laminectomy, intraoperative US imaging confirmed verrucous vegetation and epidural fluid collection around the ventral dural defect before incision of the posterior dura mater. As intraoperative US also showed a dural defect at the ventral and right sides of the spinal cord, the posterior dural incision was made in a manner that was slightly more right lateral than standard midline. The ventral dural defect was repaired by direct sutures. After repair, intraoperative US imaging confirmed dural hole closure, removal of vegetation and resolution of the collected fluid. Dural closure was successful and symptoms partially improved despite the patient’s long history of SS. Intraoperative US can help surgeons make decisions about precise dural incision before repair. Intraoperative US is useful for detecting the level of dural defect and verrucous vegetation before repair and confirming closure of the dural defect, successful removal of vegetation and resolution of fluid collection after repair.

Sagittal alignment at 3 years old determines future thoracolumbar kyphosis in achondroplasia: A prospective study with minimum 5-year follow-up from infancy

Background

Little is known about the progression of Thoracolumbar kyphosis (TLK) in achondroplasia. The aim of the study was to evaluate natural progression of TLK and establish risk factors for progression.

Methods

We reviewed 21 patients (11 males, 10 females) diagnosed clinically and radiographically with achondroplasia as infants and followed for a minimum of 5 years from infancy, and analyzed to compare differences between data at 0, 1, 3, 5, 7-10, and 11-18 years old. Subjects (n=21) were divided into two groups with and without TLK >20° at the thoracolumbar junction on lateral standing radiographs at age 3.

Results

TLK >20° occurs in 76.2% of infants in the first 7 months of life. Sagittal parameters at 0, 1, 3, 5, 7-10, and 11-18 years old differed significantly for cervical lordosis (CL), thoracic kyphosis (TK), TLK, lumbar lordosis (LL), pelvic tilt (PT), and sacral slope (SS). TK, LL, and SS increased significantly with increasing age, whereas CL, TLK, and PT were significantly lower in older age groups (P < 0.05). In 6 of 7 patients with TLK >20° at age 3, TLK had progressed or was still >20° at age 5. The prevalence of TLK >20° at age 3 was 33.3% (7/21). There was a significant difference in age at independent walking among subjects with and without TLK at age 3 (31.4±17.1 vs. 16.1±3.4 months, P < 0.01). Radiologic parameters associated with TLK showed significant differences between subjects with and without TLK at age 3, including TLK, TK, TLK, LL, and SVA at age 5; and TLK at ages 7-10 and 11-18.

Conclusions

These results suggest that sagittal alignment at 3 years old determines future TLK in achondroplasia. Progression of deformity and neurological impairments require consideration in treatment planning.

Predictors for quality of life improvement after surgery for degenerative cervical myelopathy: a prospective multi-center study

BACKGROUND

Degenerative cervical myelopathy (DCM) can significantly impair a patient's quality of life (QOL). In this study, we aimed to identify predictors associated with QOL improvement after surgery for DCM.

METHODS

This study included 148 patients who underwent surgery for DCM. The European QOL-5 Dimension (EQ-5D) score, the Japanese Orthopedic Association for the assessment of cervical myelopathy (C-JOA) score, and the Nurick grade were used as outcome measures. Radiographic examinations were performed at enrollment. The associations of baseline variables with changes in EQ-5D scores from preoperative to 1-year postoperative assessment were investigated using a multivariable linear regression model.

RESULTS

The EQ-5D and C-JOA scores and the Nurick grade improved after surgery (P < 0.001, P < 0.001, and P < 0.001, respectively). Univariable analysis revealed that preoperative EQ-5D and C-JOA scores were significantly associated with increased EQ-5D scores from preoperative assessment to 1 year after surgery (P < 0.0001 and P = 0.045). Multivariable regression analysis showed that the independent preoperative predictors of change in QOL were lumbar lordosis (LL), sacral slope (SS), and T1 pelvic angle (TPA). According to the prediction model, the increased EQ-5D score from preoperatively to 1 year after surgery = 0.308 - 0.493 × EQ-5D + 0.006 × LL - 0.008 × SS + 0.004 × TPA.

CONCLUSIONS

Preoperative LL, SS, and TPA significantly impacted the QOL of patients who underwent surgery for DCM. Less improvement in QOL after surgery was achieved in patients with smaller LL and TPA and larger SS values. Patients with these risk factors may therefore require additional support to experience adequate improvement in QOL.

Risk Factors for Neuropathic Pain in Middle-Aged and Elderly People: A Five-Year Longitudinal Cohort in the Yakumo Study

OBJECTIVE

To determine the risk factors for new neuropathic pain (NeP) after five years in healthy middle-aged and elderly volunteers.

DESIGN

Prospective longitudinal cohort study (Yakumo study).

SETTING

Clinical evaluation in a health checkup.

SUBJECTS

A total of 366 people (male N = 146, female N = 220, average age = 63.5 years) who did not have NeP in 2013 were examined.

METHODS

NeP was diagnosed based on a painDETECT questionnaire score ≥13. Body mass index (BMI), comorbidity, low back pain (LBP), sciatica, physical ability, grip and back muscle strength, osteoporosis, sarcopenia, frailty, spinal alignment, and quality of life (QOL) with the SF36 in 2013 were compared between NeP(+) and NeP(-) subjects in 2018 using multivariate logistic regression analysis.

RESULTS

The NeP(+) rate in 2018 was 5.2%, with no significant differences in age and gender. NeP(+) subjects had significantly lower BMI, severe sciatica, poor gait ability, higher rates of osteoporosis and sarcopenia, greater lumbar kyphosis and spinal inclination, and poorer mental health in 2013. Poor gait ability (odds ratio [OR] = 8.05), low BMI (OR = 2.31), lumbar kyphosis (OR = 1.38), low percentage of the young adult mean (OR = 1.15), and low mental QOL (OR = 1.06) were identified as significant and independent risk factors for new NeP after five years.

CONCLUSIONS

This longitudinal cohort study identified five independent risk factors for development of new NeP after five years, with related factors of spinal inclination, sarcopenia, and sciatica. New NeP may be prevented by intervention or treatment of these factors at an early stage in relatively healthy middle-aged and elderly people.

Predictors associated with neurological recovery after anterior decompression with fusion for degenerative cervical myelopathy

BACKGROUND

Anterior decompression with fusion (ADF) has often been performed for degenerative cervical myelopathy (DCM) in patients with poor cervical spine alignment and/or anterior cord compression. We aimed to identify clinical and radiological predictors associated with neurological recovery after ADF.

METHODS

This post-hoc analysis from a prospective multicenter study included patients who were scheduled for ADF for DCM. The patients who received other surgeries (laminoplasty, posterior decompression and fusion) were excluded. The associations between baseline clinical and radiographic variables (age, sex, body mass index, etiology, cervical lordosis, range of motion, C7 slope, C2-7 sagittal vertical axis [SVA], thoracic kyphosis [TK], lumbar lordosis, sacral slope, SVA, pelvic tilt, T1 pelvic angle [TPA], the Japanese Orthopedic Association score for the assessment of cervical myelopathy [C-JOA], European Quality of Life Five Dimensions Scale [EQ-5D], Neck Disability Index [NDI], Physical Component Summary of the SF-36 [PCS], and Mental Component Summary of the SF-36) and the recovery rates as the outcome variables were investigated in the univariate regression analysis. Then, the independent predictors for increased recovery rates were evaluated using a stepwise multiple regression analysis.

RESULTS

In total, 37 patients completed the 1 year follow-up. The recovery rate was significantly correlated with SVA (p = 0.001) and TPA (p = 0.03). Univariate regression analyses showed that age (Regression coefficient = - 0.92, p = 0.049), SVA (Regression coefficient  = - 0.57, p = 0.004) and PCS (Regression coefficient = 0.80, p = 0.03) score were significantly associated with recovery rate. Then, a stepwise multiple regression analysis identified the independent predictors of recovery rate after ADF as TK (p = 0.01), PCS (p = 0.03), and SVA (p = 0.03). According to this prediction model, the following equation was obtained: recovery rate = - 8.26 + 1.17 × (TK) - 0.45 × (SVA) + 0.85 × (PCS) (p = 0.002, R² = 0.44).

CONCLUSION

Patients with lower TK, lower PCS score, and higher SVA were more likely to have poor neurological recovery after ADF. Therefore, patients with DCM and these predictors who undergo ADF should be warned about poor recovery and be required to provide adequate informed consent.

Kinetic changes in the spinal cord occupation rate of dural sac in cervical spondylotic myelopathy

Objective

The study aimed to establish the spinal cord occupation rate of the dural sac during flexion and extension.

Methods

We measured the cross-sectional area of the dural sac and the spinal cord between C2/C3 and C7/T1 disc levels in 100 patients with cervical spondylotic myelopathy and 1211 asymptomatic subjects.

Results

The spinal cord occupation rate of the dural sac in the cross-sectional area was higher on extension than on flexion at the mid-lower cervical spine.

Conclusions

The spinal cord occupation rate of the dural sac in the cross-sectional area was highest at the C4/C5 and C5/C6 levels on extension.

Postoperative Syrinx Shrinkage in Spinal Ependymoma of WHO Grade II

STUDY DESIGN

A retrospective study of preoperative and postoperative magnetic resonance imaging (MRI) findings in spinal ependymoma.

OBJECTIVE

The goal of the study was to examine MRI features, including the syrinx component volume, after surgical resection of spinal ependymoma, and to relate these features to extent of resection and improvement of postoperative neurological status.

SUMMARY OF BACKGROUND DATA

Spinal ependymomas have a variety of MRI findings preoperatively, including a hemorrhage cap sign, gadolinium enhancement, and a spinal tumor cyst. However, little is known about these features on postoperative MRI after tumor resection.

MATERIALS AND METHODS

The subjects were 38 patients treated for spinal cord ependymoma of World Health Organization grade II at our hospital. All had a spinal tumor cyst on preoperative MRI. All cases were followed with MRI for >1 year after surgery, including imaging at postoperative months (POM) 1 and 12. The maximum diameter of the syrinx was measured on mid-sagittal MRI. The extent of tumor resection was categorized as gross total resection (GTR) and subtotal resection (STR).

RESULTS

The mean age of the 38 patients (22 male and 16 female individuals) was 50.9 years (range, 21-71 y) at the time of surgery. The mean preoperative duration from disease onset was 14.9 months (range, 2-47 mo). GTR was achieved in 28 patients (74%) and STR in 10 (26%). The mean syrinx sizes preoperatively and at POM 1 and POM 12 were 7.5±2.3, 4.1±1.9, and 2.5±1.8 mm, respectively, with significant differences among the time points (P<0.01). The syrinx size shrunk over time after GTR and STR. The shrinkage rate was significantly higher in GTR cases (P<0.05) and in cases with the improvement of McCormick grade for neurological status after both GTR and STR (P<0.05).

CONCLUSIONS

These findings suggest that MRI can be used to evaluate the improvement of neurological status after surgery for spinal ependymoma.

Risk Factors for Poor Outcome of Cervical Laminoplasty: Multivariate Analysis in 505 Patients with Cervical Spondylotic Myelopathy

The risk factors for poor outcome after cervical laminoplasty in patients with cervical spondylotic myelopathy (CSM) were demonstrated. These findings suggest that advanced age, long-term CSM symptoms, and lower score of preoperative 10-second step test are risk factors for poor cervical laminoplasty outcomes in patients with CSM.

Study Design..

A prospective study.

Objective..

The aim of this study was to characterize the risk factors for poor outcome following cervical laminoplasty in patients with cervical spondylotic myelopathy (CSM).

Summary of Background Data..

Previous research has identified a variety of potential predictive factors that might affect outcomes after cervical laminoplasty. However, no study till date has assessed the effects of such risk factors, including internal medicine comorbidity and quantitative performance tests, on the outcome of laminoplasty in a large series of patients with CSM.

Methods..

A total of 505 consecutive patients with CSM (311 males; 194 females; mean age, 66.6 years; age range, 41–91 years) who underwent double-door laminoplasty were prospectively included. The average postoperative follow-up period was 26.5 months (range, 12–66 months). We evaluated the recovery rate (RR) on the basis of the Japanese Orthopaedic Association score. Logistic regression analysis was performed to identify the risk factors for poor outcome, which was defined as a postoperative RR of <50%. Relationship between outcome and various clinical and imaging predictors was examined.

Results..

Two hundred ninety-five patients had good outcomes with RR >50%, whereas 210 patients had poor outcomes with RR <50%. Compared with the good-outcome group, the poor-outcome group had a significantly higher prevalence of diabetes and hypertension and use of anticoagulant/antiplatelet agent and smoking history (P < 0.05). Multivariate logistic regression analysis showed independent risks associated with increased age (odds ratio [ORs]  = 1.029, 95% confidence interval [CI] = 1.004–1054, P = 0.023). Logistic regression analysis determined that symptom duration of CSM (OR = 1.017, 95% CI = 1.008–1.026, P < 0.001) and preoperative 10-second step test (OR = 0.922, 95% CI = 0.865–0.983, P = 0.013) were significant risk factors for poor outcome.

Conclusion..

These findings suggest that advanced age, long-term CSM symptoms, and lower score of preoperative 10-second step test are risk factors for poor outcome in patients with CSM.

Level of Evidence: 2

Overcoming locomotive syndrome: The Yakumo Study

OBJECTIVES

Improvement of life expectancy is increasingly important with the aging of society. The aim of the study was to compare physical performance in elderly people in two 3-year periods (2001-2003) and (2016-2018).

METHODS

The participants were healthy Japanese elderly adults who attended public health check-ups in Yakumo. Results for 10 m gait time, two-step test, back muscle strength, and grip strength were examined prospectively for participants in 2001-2003 (Group A: n = 488) and 2016-2018 (Group B: n = 309) by gender and age (65-74 and 75-84 years).

RESULTS

There were significant differences between Groups A and B for 10 m gait time (age 65-74: male: 5.6 vs. 5.2 s, female: 6.3 vs. 5.5 s; age 75-84: male: 6.1 vs. 5.5 s, female: 6.7 vs. 5.8 s; all p < .05) and two-step test (age 65-74: male: 1.41 vs. 1.48, female: 1.35 vs. 1.44; age 75-84: male: 1.32 vs. 1.41, female: 1.30 vs. 1.38; all p < .05), but not for back muscle strength or grip strength.

CONCLUSION

Our results suggest a phenomenon of 'overcoming locomotive syndrome', in which physical performance changed by aging, including motor functions such as 10 m gait time and two-step test, has improved in the current population compared with a similar population from 15 years ago.

Association between locomotive syndrome and the Japanese version of the EQ-5D-5L in middle-aged and elderly people in Japan

The Japanese version of the EuroQol 5 dimension, 5 level version (EQ-5D-5L) can now be used to quantitatively evaluate the health-related quality of life (QoL) in Japan. Locomotive syndrome (LS) is a concept advocated in Japan to describe a condition requiring care for musculoskeletal disorders. However, no detailed study on the relationship between this index and LS in Japanese health checkup has been reported. We aimed to evaluate the relationship between the Japanese version of the EQ-5D-5L and LS. We enrolled 477 participants who were undergoing health checkups in Japan. All participants were administered the 25-question Geriatric Locomotive Functional Scale for the diagnosis of LS and the Japanese version of the EQ-5D-5L. We performed statistical analysis to compare the non-LS and LS patients; moreover, the risk factors and cut-off values were calculated and verified. The Japanese version of the EQ-5D-5L index was significantly lower in patients with LS than in non-LS patients and was significantly related to LS in logistic regression analysis. In subgroup analysis targeting the five dimensions of the EQ-5D-5L, it was seen that mobility, pain/discomfort, and self-care were significantly involved in LS. The cut-off value of the EQ-5D-5L index for LS was 0.875. The Japanese version of the EQ-5D-5L index was significantly related to LS in Japan. This index will be a useful tool that can easily measure health-related quality of life in middle-aged and elderly Japanese people. Future studies should investigate the relationship of not only LS but also various diseases with the Japanese version of the EuroQol 5 dimension, 5 level version.

Automated Detection of Spinal Schwannomas Utilizing Deep Learning Based on Object Detection From Magnetic Resonance Imaging

STUDY DESIGN

A retrospective analysis of magnetic resonance imaging (MRI) was conducted.

OBJECTIVE

This study aims to develop an automated system for the detection of spinal schwannoma, by employing deep learning based on object detection from MRI. The performance of the proposed system was verified to compare the performances of spine surgeons.

SUMMARY OF BACKGROUND DATA

Several MRI scans were conducted for the diagnoses of patients suspected to suffer from spinal diseases. Typically, spinal diseases do not involve tumors on the spinal cord, although a few tumors may exist at the unexpectable level or without symptom by chance. It is difficult to recognize these tumors; in some cases, these tumors may be overlooked. Hence, a deep learning approach based on object detection can minimize the probability of overlooking these tumors.

METHODS

Data from 50 patients with spinal schwannoma who had undergone MRI were retrospectively reviewed. Sagittal T1- and T2-weighted magnetic resonance imaging (T1WI and T2WI) were used in the object detection training and for validation. You Only Look Once version3 was used to develop the object detection system, and its accuracy was calculated. The performance of the proposed system was compared to that of two doctors.

RESULTS

The accuracies of the proposed object detection based on T1W1, T2W1, and both T1W1 and T2W1 were 80.3%, 91.0%, and 93.5%, respectively. The accuracies of the doctors were 90.2% and 89.3%.

CONCLUSION

Automated object detection of spinal schwannoma was achieved. The proposed system yielded a high accuracy that was comparable to that of the doctors.Level of Evidence: 4.

Primary cervical decompression surgery may improve lumbar symptoms in patients with tandem spinal stenosis

PURPOSE

Tandem spinal stenosis (TSS) refers to coexisting lumbar and cervical canal stenosis. Evidence regarding whether cervical decompression improves lumbar symptoms in TSS is insufficient. Therefore, we determined the effectiveness of cervical decompression surgery for patients with lumbar spinal stenosis (LSS) and cervical spinal stenosis.

METHODS

The records of 64 patients with TSS experiencing lumbar symptoms who underwent cervical decompression surgery between April 2013 and July 2017 at a single institution were retrospectively reviewed. We categorized patients into the Non-improved (n = 20), Relapsed (n = 30), and Maintained-improvement (n = 14) groups according to the presence or absence of improvement and relapse in lower limb symptoms in TSS following cervical decompression surgeries.

RESULTS

Of 64 patients, 44 (69%) showed improved lower limb or low back symptoms, with 14 (22%) patients maintaining improvement. The preoperative cervical myelopathy-Japanese Orthopedic Association score and the preoperative number of steps determined using the 10-s step test were significantly lower in the Non-improved group than in the Maintained-improvement group. Receiver operating characteristic curve of preoperative 10-s step test results revealed 12 steps as a predictor for maintained improvement.

CONCLUSION

The improvement of LSS symptoms following cervical decompression surgeries may be associated with the severity of cervical myelopathy as determined in clinical findings rather than in imaging findings. Patients with TSS having a 10-s step test result of < 12 steps were more likely to experience a relapse of lower limb symptoms following cervical decompression surgeries.

Poor derivation of Tc-MEP baseline waveforms in surgery for ventral thoracic intradural extramedullary tumor: Efficacy of use of the abductor hallucis in cases with a preoperative non-ambulatory status

Most thoracic intradural extramedullary tumors (IDEMT) are benign lesions that are treated by gross total resection and spinal cord decompression. Intraoperative transcranial-motor evoked potential (Tc-MEP) monitoring is important for reducing postoperative neurological complications. The purpose of this study is to examine the characteristics of Tc-MEP waveforms in surgery for thoracic IDEMT resection based on location of the tumor relative to the spinal cord. The subjects were 56 patients who underwent surgery for thoracic IDEMT from 2010 to 2018. The waveform derivation rate for each lower muscle was examined at baseline and intraoperatively. 56 patients had a mean age of 61.7 years, and 21 (38%) were non-ambulatory before surgery. The tumors were schwannoma (n = 28, 50%), meningioma (n = 25, 45%), and neurofibroma (n = 3, 5%); and the lesions were dorsal (n = 29, 53%) and ventral (n = 27, 47%). There was a significantly higher rate of undetectable waveforms in all lower limb muscles in the ventral group compared to the dorsal group (15% vs. 3%, p < 0.05). In non-ambulatory cases, the derivation rate at baseline was significantly lower for ventral thoracic IDMETs (47% vs. 68%, p < 0.05). The abductor hallucis (AH) had the highest waveform derivation rate of all lower limb muscles in non-ambulatory cases with a ventral thoracic IDMET. Spinal cord compression by a ventral lesion may be increased, and this may be reflected in greater waveform deterioration. Of all lower limb muscles, the AH had the highest derivation rate, even in non-ambulatory cases with a ventral IDEMT, which suggests the efficacy of multichannel monitoring including the AH.

Trends in Medical Costs for Adolescent Idiopathic Scoliosis Surgery in Japan

STUDY DESIGN

A retrospective review of clinical data and costs was performed for surgeries for adolescent idiopathic scoliosis (AIS) conducted from 2008 to 2017.

OBJECTIVE

Cost containment and healthcare value have become focal points in Japanese health care policy. The purpose of the study was to investigate trends over time in medical costs for surgery for AIS.

METHODS

A total of 83 patients underwent surgery for AIS from 2008 to 2017 at our hospital. Clinical data and length of stay were collected, and medical costs for surgery, local bone grafting, fees per day, and surgical instruments were evaluated.

RESULTS

There were slight year-by-year decreases in fees per day and decreases in costs of surgical instruments. The average length of stay was 16.4 days and gradually decreased over time. In contrast, scoliosis surgery costs increased about 1.6 times in 10 years from $9515 to $15 130.

CONCLUSION

The trends for decreases in fees per day and prices for surgical instruments reflect recent government medical cost control policies. The cost for scoliosis surgery is also defined by the government, and the increase over 10 years may reflect the perspective of valuing effective and advanced surgeries. This study of cost trends of operative spinal intervention provides an assessment of surgical benefit and is likely to influence health care costs.

Prediction of outcome following laminoplasty of cervical spondylotic myelopathy: Focus on the minimum clinically important difference

The minimum clinically important difference (MCID) of the Japanese Orthopaedic Association (JOA) score has been reported to be around 2.5 points in cervical myelopathy. This study sought to define significant predictive factors on achieving the MCID following laminoplasty in a large series of patients with cervical spondylotic myelopathy (CSM). A total of 485 consecutive patients with CSM (295 males and 190 females; mean age: 67.0 years; age range: 42-91 years) who underwent laminoplasty were prospectively enrolled. The average postoperative follow-up period was 26.6 months (range: 12-66 months). We calculated the achieved JOA score. The relationships between outcomes and various clinical and imaging predictors including comorbidity and quantitative performance tests were examined. Logistic regression analysis was conducted to identify the predictors correlated with a JOA score of 2.5 points or more. Clinically meaningful gains were exhibited in 299 patients (61.6%) with a JOA score of ≥2.5 points, whereas 186 patients (38.4%) achieved a JOA score of <2.5 points. Univariate logistic regression analysis showed the predictive factors with a shorter duration of CSM symptoms, lower preoperative JOA scores, absence of hypertension, no use of anticoagulant/antiplatelet agents, and nonsmoking status. Multivariate logistic regression analysis determined that the duration of CSM symptoms (odds ratio: 0.771, 95% confidence interval: 0.705-0.844; p < 0.01) was the only significant predictive factor for achieving JOA scores of ≥2.5 points. An important predictor of MCID achievement following laminoplasty was shorter duration of CSM symptoms.

Surgical outcomes and factors related to postoperative motor and sensory deficits in resection for 244 cases of spinal schwannoma

In a large cohort the clinical presentation, management and outcomes of spinal schwannoma and factors related to postoperative motor and sensory deficits were invesgtigated. In 244 patients (males: 126, females: 118, average age 51.8 y) at one center, significant factors related to postoperative motor and sensory deficits were identified. Tumors were in the cervical (n = 79, 32.4%), lumbar (n = 66), thoracolumbar (T11-L1) (n = 55), and thoracic (n = 39) regions, and 5 patients had sacrum tumors. The rates of postoperative motor and sensory deterioration were 13.1% and 20.5%, respectively. The risk factors for motor deterioration were preoperative motor weakness, preoperative gait disturbance, dumbbell Eden type II, subtotal resection, and operative time, and those for postoperative sensory deficit were preoperative gait disturbance and subtotal resection. Of 12 patients with significant TcMEP changes, 11 had a new motor deficit after surgery; and of 216 patients with stable TcMEP data, 196 were neurologically intact after surgery (true negative) and 20 (11.0%) had deficits in the immediate postoperative stage (false negative). These deficits resolved during hospitalization for most patients. Of 15 patients with TcMEP deterioration and recovery, 11 (93.3%) had no motor deficits after surgery (p < 0.01).

Larger muscle mass of the upper limb correlates with lower amplitudes of deltoid MEPs following transcranial stimulation

To perform spinal surgery safely, it is important to understand the risk factors, including factors that negatively influence intraoperative neuromonitoring (IONM). Transcranial motor evoked potentials (TcMEPs) are important in IONM. Therefore, we aimed to investigate whether muscle mass affects the waveforms of TcMEPs to understand the risk factors influencing TcMEPs. We enrolled 48 patients with thoracolumbar spinal diseases who underwent surgery at our facility between April 2015 and March 2018. Before surgery, the body composition, including muscle mass and fat mass, of all patients was measured using bioelectrical impedance analysis (BIA). During surgery, cranial stimulation under general anesthesia was used to derive TcMEPs, enabling us to measure the amplitude, using the control wave of the TcMEPs of the deltoid muscles and the abductor digiti minimi (ADM) muscles. We found a negative correlation between the amplitude of deltoid-muscle TcMEPs and muscle mass of the upper limb. The amplitude of deltoid-muscle TcMEPs did not correlate with the skeletal muscle index (SMI), muscle mass of the lower limb, or body fat mass. The amplitude of ADM-muscle TcMEPs did not correlate with SMI, muscle mass of any limb, or body fat mass. In conclusion, a larger muscle mass of the upper limb correlated with a lower amplitude of deltoid-muscle TcMEPs. By contrast, there was no correlation between the muscle mass of the upper limb and the amplitude of ADM-muscle TcMEPs. These findings suggest that TcMEPs of the ADM are less influenced by muscle mass and are more stable than those of the deltoid.

Impact of Rigid Fixation of the Pubic Symphysis for Spinopelvic Fixation in Two Cases of Lumbosacral Agenesis

Introduction

In patients with lumbosacral agenesis (SA), Renshaw type III or IV, lumbosacral instability is the primary cause of major clinical complications. Although they are usually treated with spinopelvic fusion, nonunion at the spinopelvic junction is a major complication due to the congenital sacropelvic abnormalities. The purpose of this study was to evaluate whether a combination of lumbosacral fixation and rigid fixation at the pubic symphysis could lead to postoperative bone union in patients with SA (Renshaw type III).

Methods

Retrospective case series study. We present the cases of two patients with SA, Renshaw type III, who were surgically treated by lumbosacral fusion using a posterior approach, and they exhibited nonunion at the lumbosacral junction.

Results

Case 1. A 10-year-old male underwent T8-S posterior fixation followed by multiple augmentations using allografts at the lumbosacral junction for delayed union. All additional procedures with bone graft using a posterior approach failed to achieve bone union; however, additional rigid fixation at the pubic symphysis resulted in a successful lumbosacral bone union.

Case 2. A 6-year-old male underwent vertical expandable prosthetic titanium rib (VEPTR) surgery with multiple rod extension procedures. Subsequently, at the age of 10 years, a combined two-stage anterior (L1-3) and posterior (T8-iliac) fixation with T9 hemivertebrectomy was performed. As a result of subsequent nonunion with screw loosening, additional rigid fixation at the pubic symphysis was performed 1 month after posterior fixation. Bone union was finally achieved 1 year after all the surgical interventions.

Conclusions

Rigid fixation at the pubic symphysis may play a significant role in achieving rigid bone union for unstable lumbopelvic connection, such as SA, Renshaw type III or IV.

Dynapenia and physical performance in community-dwelling elderly people in Japan

Aging of society has increased the incidence of physical disability. The goal of this study was to examine the physical ability of elderly people classified as having sarcopenia, presarcopenia, or dynapenia (a low muscle function without low muscle mass) in a community in Japan. The subjects were volunteers aged >60 years who were participants in a health checkup in Yakumo, Hokkaido and were in good general health. Demographic data were collected and physical performance tests were performed to measure grip strength, walking speed, back muscle strength, maximum stride length, and 3-m timed-up-and-go (3m TUG) time. A measurement of skeletal muscle mass was used as a basis for calculating the appendicular skeletal muscle index (aSMI). The rates of sarcopenia, presarcopenia, and dynapenia were 10%, 22%, and 8% in males (n=101, age 69.7±5.4 years), and 19%, 23%, and 13% in females (n=112, 68.5±5.9 years). Body mass index in subjects with dynapenia was significantly higher compared to that in subjects with sarcopenia and presarcopenia (p<0.01). Back muscle strength, maximum stride length and 3m TUG were similar in dynapenia and sarcopenia, but differed significantly with those in presarcopenia in both males and females without the influence of age (p<0.05). Further studies are needed to evaluate the benefits of dynapenia intervention programs and to explore the underlying pathophysiology of dynapenia.

Postoperative changes in spinal cord signal intensity in patients with spinal cord injury without major bone injury: comparison between preoperative and postoperative magnetic resonance images

OBJECTIVE

Although increased signal intensity (ISI) on MRI is observed in patients with cervical spinal cord injury (SCI) without major bone injury, alterations in ISI have not been evaluated. The association between postoperative ISI and surgical outcomes remains unclear. This study elucidated whether or not the postoperative classification and alterations in MRI-based ISI of the spinal cord reflected the postoperative symptom severity and surgical outcomes in patients with SCI without major bone injury.

METHODS

One hundred consecutive patients with SCI without major bone injury (79 male and 21 female) with a mean age of 55 years (range 20-87 years) were included. All patients were treated with laminoplasty and underwent MRI pre- and postoperatively (mean 12.5 ± 0.8 months). ISI was classified into three groups on the basis of sagittal T2-weighted MRI: grade 0, none; grade 1, light (obscure); and grade 2, intense (bright). The neurological statuses were evaluated according to the Japanese Orthopaedic Association (JOA) scoring system and the American Spinal Injury Association Impairment Scale (AIS).

RESULTS

Preoperatively, 8 patients had grade 0 ISI, 49 had grade 1, and 43 had grade 2; and postoperatively, 20 patients had grade 0, 24 had grade 1, and 56 had grade 2. The postoperative JOA scores and recovery rate (RR) decreased significantly with increasing postoperative ISI grade. The postoperative ISI grade tended to increase with the postoperative AIS grade. Postoperative grade 2 ISI was observed in severely paralyzed patients. The postoperative ISI grade improved in 23 patients (23%), worsened in 25 (25%), and remained unchanged in 52 (52%). Patients with an improved ISI grade had a better RR than those with a worsened ISI grade.

CONCLUSIONS

Postoperative ISI reflected postoperative symptom severity and surgical outcomes. Alterations in ISI were seen postoperatively in 48 patients (48%) and were associated with surgical outcomes.

Dynamic changes in longitudinal stretching of the spinal cord in thoracic spine: Focus on the spinal cord occupation rate of dural sac

OBJECTIVES

This study aimed to evaluate the anteroposterior diameters and cross-sectional areas of the dural sac and spinal cord in the thoracic spine, to elucidate the spinal cord occupation rate of the dural sac in these dynamic changes for each level using multidetector-row computed tomography (MDCT).

PATIENTS AND METHODS

Fifty patients with cervical or lumbar spinal disease were prospectively enrolled. After preoperative myelography, MDCT was performed at maximum passive flexion and extension. The anteroposterior diameter and cross-sectional area of the dural sac and spinal cord in the axial plane and the thoracic spinal cord length in the sagittal plane were measured. The spinal cord occupation rate in the dural sac was calculated.

RESULTS

The spinal cord occupation rate of the dural sac in anteroposterior diameter was lower on flexion than on extension, with significant differences from the T1/T2 to T11/T12 levels (p < 0.0001). The spinal cord occupation rate of the dural sac in cross-sectional area was lower on flexion than on extension, with significant differences except from T3/T4 to T6/T7 levels (p < 0.01). There was a bimodal increase in the occupation rate with elevations at the cervicothoracic junction and thoracolumbar junction. The thoracic spinal cord length on flexion was significantly longer than that on extension (p < 0.0001).

CONCLUSIONS

The spinal cord occupation rate of the dural sac was lower on flexion than on extension, despite thoracic spine being considered a rigid region. The dynamic changes in longitudinal stretching and shrinkage of the spinal cord affected the occupation rate.

Poor spinal alignment in females with obesity: The Yakumo study

Objective

The goal of this prospective study was prospectively to investigate the relationship between obesity and spinal sagittal alignment.

Methods

286 were referred for orthopedic evaluation. Differences in spinal parameters among these groups and between males and females were evaluated.

Results

Obese subjects had significantly higher C2S, CPA, CTPA, PI-LL, and lower cervical lordosis, L4S1, lumbar lordosis, and sacral slope. In multivariate logistic regression analysis adjusted for age in females, CTPA was identified as the only independent and significant factor associated with obesity.

Conclusions

Obesity in females has significant relationships with spinal sagittal alignment and results in poorer physical QOL.

Relationship between lumbopelvic discordance and locomotive syndrome in a middle-aged community-living population: The Yakumo study

BACKGROUND

Locomotive syndrome (LS) affects the quality and activities of daily living. Although spinal sagittal balance influences LS, no report elucidated the relationship between LS risk and lumbopelvic discordance. This study aimed to investigate the relationship between lumbopelvic discordance and LS in a middle-aged community.

METHODS

The subjects (n = 135) were divided into three groups based on the LS risk stage, which was evaluated through spinopelvic sagittal alignment and lumbopelvic mismatch prevalence (Pelvic incidence-Lumbar lordosis >10°:PI-LL mismatch).Then, the subjects were divided into two groups (lumbopelvic matched and mismatched groups) and analyzed based on the demographic data, physical test, stabilometry, and body pain using the visual analog scale.

RESULTS

There were 76, 37 and 22 subjects in stages 0, 1, and 2, respectively. The pelvic incidence-lumbar lordosis (PI-LL) mismatched group had a higher prevalence in LS risk stage 2 than in LS risk stage 0. The prevalence of PI-LL mismatch was significantly different among the groups. Post hoc test revealed the differences in spinopelvic alignment among the stages. In each LS risk stage, the degree of PI-LL was significantly higher in stage 2 than that in stages 0 and 1. On comparing the PI-LL matched (n = 67) and mismatched groups (n = 68) with a stabilometer, the envelopment area tracing by the movement of the center of pressure and locus length/second was greater in the PI-LL mismatched group than that in the PI-LL matched group with/without eyes opened.

CONCLUSIONS

The prevalence of LS risk stage 2 was more frequently observed in the PI-LL mismatched group. The degree of PI-LL was evaluated through the LS risk stages. Physical dysfunction in the PI-LL mismatched group was related to trunk imbalance based on stabilometry. These findings will help manage LS and PI-LL mismatched subjects.

CTGF/CCN2 facilitates LRP4-mediated formation of the embryonic neuromuscular junction

At the neuromuscular junction (NMJ), lipoprotein-related receptor 4 (LRP4) mediates agrin-induced MuSK phosphorylation that leads to clustering of acetylcholine receptors (AChRs) in the postsynaptic region of the skeletal muscle. Additionally, the ectodomain of LRP4 is necessary for differentiation of the presynaptic nerve terminal. However, the molecules regulating LRP4 have not been fully elucidated yet. Here, we show that the CT domain of connective tissue growth factor (CTGF/CCN2) directly binds to the third beta-propeller domain of LRP4. CTGF/CCN2 enhances the binding of LRP4 to MuSK and facilitates the localization of LRP4 on the plasma membrane. CTGF/CCN2 enhances agrin-induced MuSK phosphorylation and AChR clustering in cultured myotubes. Ctgf-deficient mouse embryos (Ctgf^-/- ) have small AChR clusters and abnormal dispersion of synaptic vesicles along the motor axon. Ultrastructurally, the presynaptic nerve terminals have reduced numbers of active zones and mitochondria. Functionally, Ctgf^-/- embryos exhibit impaired NMJ signal transmission. These results indicate that CTGF/CCN2 interacts with LRP4 to facilitate clustering of AChRs at the motor endplate and the maturation of the nerve terminal.

Locomotive syndrome and the power spectral characteristics of body sway

AIM

In Japan, nursing care is advised for patients with locomotive syndrome (LS) because of musculoskeletal disorders. Balance tests have indicated an association between LS risk and sway size related to center of pressure (COP) movement. Here, the power spectrum represents the energy contained in each frequency of COP sway. Although balance tests are often performed during health checkups, no studies have investigated the relationship between the power spectrum and LS. This study investigated this relationship.

METHODS

In total, 605 recipients of health checkups were evaluated for LS using the 25-item Geriatric Locomotive Function Scale. Power spectrums were calculated by applying fast Fourier transform to COP sway time-series data. These were classified into three sections (0.02-0.2 Hz [low-frequency band; LFB], 0.2-2 Hz [mid-frequency band], and 2-10 Hz [high-frequency band; HFB]). Power spectrums were evaluated in left-right and front-back directions.

RESULTS

LS was associated with significantly lower ratios for both the HFB (P = 0.001) in the left-right direction and LFB (P = 0.007) in the front-back direction. In addition, men had significantly lower HFB ratios in the left-right direction (P = 0.032) and LFB ratios in the front-back (P = 0.013), whereas women had significantly lower HFB ratios in the left-right direction (P = 0.007).

CONCLUSIONS

LS was associated with significantly lower ratios for both the HFB in the left-right direction and LFB in the front-back direction. This understanding of the power spectral characteristics of LS may be useful in the context of pathology and therapeutic intervention. Geriatr Gerontol Int ••; ••: ••-•• Geriatr Gerontol Int 2020; ••: ••-••.

Scoliosis Caused by Limb-Length Discrepancy in Children

STUDY DESIGN

Single-center retrospective study in pediatric patients.

PURPOSE

The purpose of the study was to investigate the effects of the presence and severity of leg-length discrepancy (LLD) on scoliosis in children.

OVERVIEW OF LITERATURE

LLD is a common orthopedic problem that can result in standing imbalance, low back pain, and stress fractures. It may cause structural changes in the spine over time, but the exact effect of LLD on scoliosis is unknown.

METHODS

The subjects were 23 children with LLD ≥20 mm (range, 27-65 mm) treated at Nagoya University Hospital between 2007 and 2017. Whole spine posteroanterior standing radiographs and whole lower limb radiographs in a supine position were recorded. Data were collected for demographics, LLD, Cobb angle, pelvic obliquity, and Nash/Moe index. Scoliosis was defined as a Cobb angle ≥10°. Leg length was measured from the top of the femoral head to the middle of the tibial plafond, and LLD was defined as the difference between the left and right leg lengths.

RESULTS

The patients (nine males and 14 females) had a mean age of 14.0 years (range, 5-18 years). The average LLD was 44.3±17.2 mm, with LLDs of 20 to 39 mm, 40 to 59 mm, and ≥60 mm in 13, five, and five subjects, respectively. The average Cobb angle was 13.0°±7.0°, and 15 subjects (65%) had scoliosis. Convexity of the scoliosis was to the short leg side in all cases. The Cobb angle was significantly related to the severity of the LLD (R=0.736, p<0.01), pelvic obliquity (R=0.966, p<0.01), and Nash/Moe index (p<0.05).

CONCLUSIONS

LLD is a common pediatric condition that can cause scoliosis of the spine. Severe scoliosis may develop if the LLD is ≥30 mm. Long-term studies are needed to examine the effect of LLD resolution on the elimination of scoliosis.

Multivariate analysis of factors related to the absence of musculoskeletal degenerative disease in middle-aged and older people

AIM

Musculoskeletal degenerative disease (MSD; osteoporosis, knee arthritis and lumbar spondylosis) decreases the quality of life (QOL) of older people. The objective of the present study was to identify the factors related to the absence of MSD in multivariate logistic regression analysis.

METHODS

The participants were 1034 volunteers (444 men, 590 women, mean age 63.5 years) in the Yakumo study. Osteoporosis (percentage of young adult mean ≤70%), knee arthritis (Kellgren-Lawrence grade ≥2), and lumbar spondylosis (Nathan class ≥3) were prospectively examined. Participants were divided into those with and without MSD. Age, sex, body mass index, muscle strength, gait ability, pain, body balance, spinal sagittal alignment, geriatric syndrome (locomotive syndrome, frailty and sarcopenia) and QOL (Short Form Health Survey) were compared between these groups to identify the factors associated with the absence of MSD.

RESULTS

Significantly lower age, body mass index and pain; higher gait speed, grip and back muscle strength; more stable body balance; better sagittal spinal alignment; and lower rates of locomotive syndrome, frailty and sarcopenia were observed in the group without MSD (n = 445, 43%), with significantly better QOL (P < 0.0001). In multivariate logistic regression analysis adjusted for age and sex, lower body mass index (odds ratio [OR] 1.10, P < 0.001), lower spinal inclination (OR 1.08, P < 0.01), higher back muscle strength (OR 1.01, P < 0.05), no locomotive syndrome (OR 1.80, P < 0.05) and good body balance (OR: 1.12, P < 0.05) were significant factors for the absence of MSD.

CONCLUSIONS

Factors related to an absence of MSD are also related to good QOL, and should be a focus of health interventions in healthy middle-aged and older people. Geriatr Gerontol Int 2019; 19: 1141-1146.

Higher extracellular water-to-total body water ratio more strongly reflects the locomotive syndrome risk and frailty than sarcopenia

OBJECTIVE

Among body composition parameters measured by bioelectrical impedance analysis, the extracellular water-to-total body water (ECW/TBW) ratio is a known prognostic or related factor for various diseases. While concepts such as locomotive syndrome risk, frailty, and sarcopenia are gaining popularity in Japan, their relationship with the ECW/TBW ratio has not been examined in detail. This study aimed to investigate the relationships between them.

METHODS

Of 1081 individuals who underwent health checkups, 550 were included in this study. The evaluations included a two-step test, stand-up test, and a 25-question geriatric locomotive function scale questionnaire. Frailty was diagnosed based on the Japanese version of the Cardiovascular Health Study criteria. Sarcopenia was evaluated according to the Asian Working Group for Sarcopenia criteria. The aforementioned ratio was measured using bioelectrical impedance analysis.

RESULTS

The ECW/TBW ratio significantly increased with locomotive syndrome risk, frailty, and sarcopenia (p < 0.001 each). Nevertheless, no significant difference was found between robust and pre-frailty groups (p = 0.71) and normal and pre-sarcopenia groups (p = 0.93). Furthermore, after correcting for age, sex, and body mass index, multiple regression analysis revealed that locomotive syndrome risk (p < 0.001) and frailty (p = 0.001) were significantly associated with an increase in the ECW/TBW ratio, whereas sarcopenia was not (p = 0.97).

CONCLUSIONS

An increase in the ECW/TBW ratio may reflect locomotive syndrome risk and frailty, but not sarcopenia. In bioelectric impedance analysis, this ratio is an important indicator; if it is high, it is necessary to consider locomotive syndrome risk and frailty.

Impact of pelvic incidence on lumbar osteophyte formation and disc degeneration in middle-aged and elderly people in a prospective cross-sectional cohort

PURPOSE

Pelvic incidence (PI) is unique to each individual and does not change throughout life. High PI is related to lumbar spondylolisthesis, but associations of PI with lumbar osteophyte formation and disc degeneration are unclear. The objective was to evaluate relationships of PI with lumbar osteophyte formation and disc degeneration, as well as spinal sagittal alignment and geriatric diseases, in middle-aged and elderly people.

METHODS

A total of 1002 volunteers (male: 434, female: 568, average age: 63.5) were prospectively examined for lumbar osteophyte formation (Nathan class ≥ 2) and disc degeneration (disc score ≥ 3). High (PI > 51, n = 501) and low (PI ≤ 51, n = 501) PI groups were defined. Clinical factors, frailty, sarcopenia, and physical quality of life (QOL) were compared between these groups, and risk factors for lumbar osteophyte formation and disc degeneration were identified in multivariate logistic regression analysis.

RESULTS

Physical QOL was poorer in people with lumbar osteophyte formation (54.8%) and disc degeneration (33.6%). Age, male gender, spinal parameters including PI, bone mineral density, back muscle strength, and gait ability differed significantly between the groups, whereas frailty and sarcopenia were not significantly different. Low PI, low lumbar lordosis, elder age, male gender, high BMI, and weak back muscle strength were significant risk factors for lumbar osteophyte formation and disc degeneration.

CONCLUSIONS

Low PI was identified as a risk factor for lumbar osteophyte formation and disc degeneration, both of which reduce physical QOL in middle-aged and elderly people. These slides can be retrieved under Electronic Supplementary Material.

Connection of discontinuous segments in early functional recovery from thoracic ossification of the posterior longitudinal ligament treated with posterior instrumented surgery

OBJECTIVE

The objective of this study was to investigate the relationship between morphological changes in thoracic ossification of the posterior longitudinal ligament (T-OPLL) and postoperative neurological recovery after thoracic posterior fusion surgery. Changes of OPLL morphology and postoperative recovery in cases with T-OPLL have not been examined.

METHODS

In this prospective study, the authors evaluated data from 44 patients (23 male and 21 female) who underwent posterior decompression and fusion surgery with instrumentation for the treatment of T-OPLL at our hospital. The patients’ mean age at surgery was 50.7 years (range 38–68 years). The minimum duration of follow-up was 2 years. The location of thoracic ossification of the ligamentum flavum (T-OLF), T-OLF at the OPLL level, OPLL morphology, fusion range, estimated blood loss, operative time, pre- and postoperative Japanese Orthopaedic Association (JOA) scores, and JOA recovery rate were investigated. Reconstructed sagittal multislice CT images were obtained before and at 3 and 6 months and 1 and 2 years after surgery. The basic fusion area was 3 vertebrae above and below the OPLL lesion. All parameters were compared between patients with and without continuity across the disc space at the OPLL at 3 and 6 months after surgery.

RESULTS

The preoperative morphology of OPLL was discontinuous across the disc space between the rostral and caudal ossification regions on sagittal CT images in all but one of the patients. Postoperatively, these segments became continuous in 42 patients (97.7%; occurring by 6.6 months on average) without progression of OPLL thickness. Patients with continuity at 3 months had significantly lower rates of diabetes mellitus (p < 0.05) and motor palsy in the lower extremities (p < 0.01). The group with continuity also had significantly higher mean postoperative JOA scores at 3 (p < 0.01) and 6 (p < 0.05) months and mean JOA recovery rates at 3 and 6 months (both p < 0.01) after surgery.

CONCLUSIONS

Preoperatively, discontinuity of rostral and caudal ossified lesions was found on CT in all patients but one of this group of 44 patients who needed surgery for T-OPLL. Rigid fixation with instrumentation may have allowed these segments to connect at the OPLL. Such OPLL continuity at an early stage after surgery may accelerate spinal cord recovery.

A Study of Risk Factors for Early-Onset Adjacent Vertebral Fractures After Kyphoplasty

STUDY DESIGN

Retrospective study.

OBJECTIVES

To elucidate risk factors for early-onset (2 months after initial kyphoplasty) adjacent vertebral fracture (EO-AVF) after kyphoplasty.

METHODS

A total of 108 vertebral bodies (95 patients) were included in this study. We examined patient backgrounds, the spinal level of EO-AVFs, surgery-related factors, and imaging findings. We divided the cases into 2 groups: patients with EO-AVF and patients without EO-AVF. Univariate, correlation, and multivariate analyses were conducted to reveal the risks factors for EO-AVFs for these 2 groups.

RESULTS

EO-AVFs developed in 28 vertebral bodies; they did not develop in 80 vertebral bodies. The overall EO-AVF incidence rate was 26%. The spinal level was the thoracolumbar junction for 93% of patients and another level for 7%, thus demonstrating the concentration of EO-AVFs in the thoracolumbar junction. For patients without EO-AVF and those with EO-AVF, there were significant differences in age (76 and 80 years, respectively), preoperative vertebral angles (VAs) (17.8° and 23°, respectively), and corrected VAs (7.3° and 12.7°, respectively). Significant differences were not observed for other factors. Pearson's correlation coefficient was 0.661 (P < .000), thereby showing a significantly positive correlation between preoperative VAs and corrected VAs. Logistic regression analysis indicated that age (odds ratio, 1.112; 95% CI, 1.025-1.206) and preoperative VAs (odds ratio, 1.08; 95% CI, 1.026-1.135) were covariates and that the presence of an EO-AVF was a dependent variable. Therefore, both were predictable risk factors for EO-AVFs.

CONCLUSION

Age, preoperative VAs, and corrected VAs are risk factors for EO-AVFs after kyphoplasty.

Persistence of Denosumab Therapy among Patients with Osteoporosis

Study Design

Retrospective study in a single center.

Purpose

To examine denosumab persistence in patients of different ages with severe osteoporosis in Japan.

Overview of Literature

Denosumab is an antibody drug used for the treatment of osteoporosis. It is mainly used in patients with severe osteoporosis who might have high motivation for treatment, and the need for only semi-annual subcutaneous injection might improve the continuation rate. However, no English-language articles have reported on denosumab persistence in the Japanese population, including young people, despite the importance of this issue in a super-aging society.

Methods

The subjects started treatment with subcutaneous denosumab in our department from July 2013 until December 2017. Persistence rates were calculated using Kaplan-Meier curves. Patients were defined as “persistent” or “non-persistent” according to the use of therapy after 60 months.

Results

The study included 101 patients (84 females) with a median follow-up period of 23.6±14.2 months. The persistence rate declined to 85.3%, 78.3%, 74.1%, 71.3%, and 69.3% at 12, 24, 36, 48, and 60 months, respectively. Age at the initiation of denosumab therapy differed significantly between non-persistent (n=31) and persistent (n=70) patients (81.3 vs. 72.8 years, p<0.01). Persistence was significantly lower in patients aged ≥80 years than in those aged <60 and 60–79 years (both p<0.01). The reasons for non-persistence of denosumab therapy were transfer to another hospital (n=13), interruption of outpatient visits (n=11), dental treatment (n=4), adverse events (n=2), and patient request (n=1).

Conclusions

Persistence was significantly lower in patients aged ≥80 years than in patients of other ages, and strategies promoting persistence are needed for these elderly patients.

Differences of lumbopelvic sagittal parameters among community-dwelling middle-age and elderly individuals: Relations with locomotor physical function

This study aims to establish radiographic parameters of lumbopelvic sagittal alignment, gender related differences, and age-related changes in a middle-aged community, to investigate whether age-related changes of lumbopelvic alignment reflect the risk of locomotive syndrome (LS). This study included 448 healthy Japanese volunteers who attended a basic health checkup supported by the local government. The subjects (184 males and 264 females, mean age: 62.7 years) were grouped according to their age by decade. Sagittal lumbopelvic parameters were collected by lateral spine radiographs including lumbar lordosis (L1-S1, LL), lower lumbar lordosis (L4-S1, LLL), pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS). The three tests (stand-up test, two-step test, and 25-question geriatric locomotive function scale [GLFS-25]) composing the LS risk test were performed. LL was significantly lower in males than in the females. A significant decrease of LL and LLL was observed from 60 s to 70 s in the females. PI did not markedly change with aging in either gender but was lower in males. A remarkable increase of PT was seen from 60 s to 70 s in the females. SS did not markedly change with aging and was lower in males in all decades. The prevalence of LS risk in males and females increased gradually with age and was greater in females in any decade. 70 s females with LS risk had significantly lower LL and higher PT compared to them without LS risk. Radiographic parameters of lumbopelvic sagittal alignment were established in community-dwelling middle-age and elderly individuals.

Increase in lumbar kyphosis and spinal inclination, declining back muscle strength, and sarcopenia are risk factors for onset of GERD: a 5-year prospective longitudinal cohort study

PURPOSE

The objective was to identify risk factors for new development of gastroesophageal reflux disease (GERD) 5 years later in a prospective longitudinal cohort study.

METHODS

A total of 178 subjects (male 72, female 106, mean age 68 years) without GERD in 2013 were examined for GERD in 2018. A Frequency Scale for Symptoms of GERD score ≥ 8 was used for diagnosis of GERD. Body mass index, spinal alignment, muscle strength, physical ability, number of oral drugs per day, sarcopenia, and frailty determined in 2013 and 2018 were compared between the GERD(+) and GERD(-) groups in 2018. Aggravation of lumbar kyphosis and spinal inclination from 2013 to 2018 was defined as a change of ≥ 5° or ≥ 10°, and weakening of back muscle strength as a change of ≥ 10 kg. QOL (SF-36) was also examined.

RESULTS

Of the 178 subjects, 38 (21%) were diagnosed as GERD(+) in 2018. Sarcopenia in 2018 was significantly related to a GERD(+) status (p < 0.05). The GERD(+) group had significantly higher rates of changes of lumbar kyphosis ≥ 5° (p < 0.005) and ≥ 10° (p < 0.0001), of spinal inclination ≥ 5° (p < 0.0001), and of decreased back muscle strength ≥ 10 kg (p < 0.05). SF-36 were also significantly worse in the GERD(+) group (p < 0.05).

CONCLUSIONS

This prospective longitudinal study firstly demonstrated that lumbar kyphotic change, aggravation of spinal inclination, decreased back muscle strength, and sarcopenia are significant risk factors for new development of GERD. Management and prevention of these factors may contribute to reduction of GERD symptoms and increased QOL in middle-aged and elderly people. These slides can be retrieved under Electronic Supplementary Material.

The decreasing phase angles of the entire body and trunk during bioelectrical impedance analysis are related to locomotive syndrome

BACKGROUND

The phase angle (measured via bioelectrical impedance analysis [BIA]) is an indicator of cell membrane function and used for prognostic evaluation of diseases. Locomotive syndrome (LS) has been advocated in the evaluation of physical ability. This study aimed to determine the relationship between LS and the phase angle as well as muscle mass, muscular strength, and motor function.

METHODS

In this prospective cohort study, 541 patients undergoing a health checkup participated. All participants were assessed using a 25-question geriatric locomotive function scale for the diagnosis of LS, phase angle, and muscle mass measurements via BIA. Grip strength, back muscle strength, and 3-m timed-up-and-go (TUG) test measurements were used as physical performance tests. Patients were divided into non-LS and LS groups, and their characteristics were compared. We assessed whether the phase angle was related to LS, whether it could be a risk factor in multivariate analysis, and the most important part of the phase angle.

RESULTS

Age, the whole body phase angle, grip strength, back muscle strength, and TUG test result were significantly different between the two groups. Logistic regression analysis revealed that the whole body phase angle and TUG test result were risk factors of LS. Based on the subanalysis targeting specific phase angles, the trunk phase angle was a significant important factor for LS.

CONCLUSION

The phase angle was significantly related to LS, and the decreased phase angle was a significant risk factor of LS together with the TUG test result. Furthermore, in subgroup analysis, the phase angle of the trunk was a significant important factor of LS. BIA can be performed conveniently, and it has been widely used for health checkups and in clinical practice. Focusing on the phase angle in BIA may be additionally helpful for the early detection and early intervention of LS.

Declining neck circumference is an anthropometric marker related to frailty in middle-aged and elderly women

Objectives: Neck circumference (NC) has been associated with cardiovascular disease and metabolic syndrome. However, the association between NC and frailty remains unknown. We aimed to determine the relationship between frailty and NC in middle-aged and elderly women.Methods: Frailty was diagnosed based on the Japanese version of the Cardiovascular Health Study criteria. Of women who underwent health checkup, 295 women with the following measurements were targeted: four trunk circumferences and appendicular skeletal muscle index (aSMI) measured using bioelectrical impedance analysis; albumin, total cholesterol, triglycerides, and C-reactive protein levels measured using a blood test; and physical function measured using back muscle strength and timed up-and-go test (TUG). Normal and frailty group comparisons were conducted using a statistical method.Results: Significant differences were observed between the two groups in terms of age, body mass index, all trunk circumferences, aSMI, back muscle strength, and TUG. Logistic regression analysis showed that NC was more related with frailty among the four trunk circumferences. In multiple regression analysis, declining NC was significantly associated with frailty.Conclusion: In middle-aged and elderly women, NC has a significant association with frailty. Declining NC was shown to be an anthropometric marker of frailty, and may be a frailty risk factor.