Abstract Study design A retrospective case control study Objective To predict proximal junctional kyphosis (PJK) risk by normalizing individual vertebral bone strength using the ratio of vertebral Hounsfield unit (HU) values around the upper instrumented vertebrae (UIV). Summary of background data PJK poses a significant challenge in treating patients after adult spinal deformity (ASD) surgery. While the vertebral body HU value is associated with PJK risk, the optimal threshold remains unclear, and a relative assessment of HU values within individuals has not been conducted. Methods Data on patients who underwent corrective fusion of the middle to lower thoracic region of the pelvis for ASD were assessed. The 126 patients were categorized into PJK and non-PJK groups. We compared the patients’ backgrounds, vertebral body HU, and junctional HU ratio, defined as the HU value of UIV+1 divided by the HU value of UIV (HU UIV+1 /HU UIV ). The UIV+2/UIV+1 HU ratio was calculated similarly. Results The PJK and non-PJK groups included 30 and 96 patients, respectively. After propensity score matching, 28 patients from each group were analyzed. HU values at UIV+2 and UIV+1 (117.0 ± 46.6 vs 145.1 ± 45.9, p=0.018, and 105.5 ± 36.2 vs 147.3 ± 44.9, p<0.001, respectively) were lower in the PJK group. Junctional HU ratio was significantly lower in the PJK group (0.88 ± 0.18 vs 1.13 ± 0.25, p<0.001), and receiver operating characteristic analysis showed that the junctional HU ratio had the highest discriminative ability (area under the curve 0.812). At the optimal cutoff value (HU ratio of 0.905), the sensitivity and specificity for PJK were 64.3% and 89.3%, respectively. Conclusions A low junctional HU ratio was strongly associated with PJK after ASD surgery. This parameter reflects the bone strength mismatch at the proximal junction and may help improve preoperative risk assessment and UIV selection.
Study DesignRetrospective cohort study.ObjectivesSurgery for adult spinal deformity (ASD) is associated with postoperative mechanical complications (MCs), such as proximal junctional kyphosis (PJK). The applicability of the Global Alignment and Proportion (GAP) score for predicting MCs in older Asians remains unclear. This study aimed to evaluate the validity of the GAP score in Asians patients by stratifying them into younger and older groups.MethodsWe studied 274 patients who had undergone multi-level spinal fusion and were followed up for at least 2 years. Patients were divided into a younger group (Under-69, n = 122) and an older group (Over-70, n = 152). MCs were assessed at 2 years postoperatively. Propensity score matching was performed to compare the incidence of MCs across groups. Logistic regression models were used to examine the interaction between GAP score and age.ResultsMC occurred in 93 patients (34%), with no significant differences between groups. In the Under-69 group, GAP scores did not correlate with MC occurrence. In contrast, the in the Over-70 group patients with MCs had significantly lower GAP scores (6.6 ± 3.4 vs. 8.0 ± 3.2, P = 0.022). The interaction between GAP score and age was not significant in the logistic regression models.ConclusionsThe GAP score demonstrated limited predictive ability for MCs in this Asian ASD cohort, particularly in older patients. These findings suggest that alignment-based prediction models alone may be insufficient for MC risk stratification in aging populations.
Abnormal pulmonary hemodynamics during exercise may persist even after balloon pulmonary angioplasty (BPA) for inoperable chronic thromboembolic pulmonary hypertension (CTEPH). We report two female patients who underwent long-term supervised outpatient cardiac rehabilitation (CR) after BPA with continuous pulmonary vasodilators. In Case 1, training was performed at an intensity close to the anaerobic threshold. In Case 2, high-intensity interval training (HIIT) was gradually introduced. Exercise right heart catheterization was used for serial assessment of the mean pulmonary arterial pressure/cardiac output slope (mPAP/CO slope). Functional outcomes were also evaluated by cardiopulmonary exercise testing. No adverse events occurred during follow-up. The mPAP/CO slope improved from 6.28 to 4.06 mmHg/L/min at 12 months in Case 1 and from 8.40 to 6.71 mmHg/L/min at 18 months in Case 2. Peak VO2 also increased from 16.2 to 20.2 mL/kg/min in Case 1 and from 18.3 to 24.9 mL/kg/min in Case 2. Long-term supervised outpatient CR after BPA appears to be feasible and may improve exercise pulmonary hemodynamics and exercise capacity.
Lumbosacral fusion (LSF) is the standard approach in adult spinal deformity (ASD) surgery but is frequently associated with proximal junctional kyphosis. Floating fusion (FF) has been proposed as an alternative approach. This study examined factors influencing the selection of FF and identified postoperative adverse factors associated with each surgical approach. This multicenter study retrospectively reviewed the records of patients who underwent surgery for ASD. They were divided into FF and LSF groups and compared by baseline patient characteristics and radiological parameters. Each group was further divided and compared according to mechanical complications (MC). The number of fusion levels (odds ratio [OR] = 0.50, 95
PURPOSE:Coronavirus disease 2019 (COVID-19) mRNA vaccines have reduced the severity and mortality of severe acute respiratory syndrome coronavirus 2 infection. However, several reports of asthma exacerbations following COVID-19 mRNA vaccination have raised safety concerns for patients with obstructive airway diseases. This study aimed to evaluate the risk of mRNA vaccine-associated exacerbations and identify associated clinical factors among patients with asthma and chronic obstructive pulmonary disease (COPD). METHODS:This multicenter historical cohort study enrolled 455 patients (387 with asthma, including 30 with COPD overlap and 68 with COPD) from 13 Japanese institutions between September 2022 and September 2024. Demographic data, pulmonary function, biomarkers, and questionnaire responses were collected. Exacerbation was defined as worsening of respiratory symptoms occurring within 1 week after vaccination. Independent risk factors were identified by multivariate logistic regression. RESULTS:Patients with asthma had a higher COVID-19 mRNA vaccine-associated exacerbation rate than those with COPD (14.5% vs. 0%, P < 0.001). Among patients with asthma, exacerbations were more frequent after COVID-19 mRNA vaccination than after influenza vaccination (14.5% vs. 1.8%, P < 0.001). Younger age, atopic predisposition, lower fractional exhaled nitric oxide levels (< 25 ppb), and poor asthma control (asthma control test < 20 and/or frequent exacerbations ≥ 2/year) were identified as independent risk factors (all P < 0.05). Most exacerbations were mild, with no severe outcomes. CONCLUSIONS:Poorly controlled atopic asthma in younger individuals was associated with increased risk of COVID-19 mRNA vaccine-associated exacerbation. Despite this, the overall benefits of COVID-19 mRNA vaccination support its continued use, with an emphasis on optimizing asthma control beforehand in high-risk patients. TRIAL REGISTRATION:UMIN Clinical Trials Registry Identifier: UMIN000049011.
