Masatoshi Hoshino

... Asian Spine Journal 2026;20(4):821-822.

Retrospective cohort study. To evaluate whether intraoperative changes in T1 tilt can predict the development of postoperative shoulder imbalance (PSI) in patients with Lenke type 2 adolescent idiopathic scoliosis (AIS). Multiple factors have been associated with PSI, but few studies have specifically investigated intraoperative radiographic predictors, such as changes in T1 tilt, in patients with Lenke type 2 AIS. Fifty patients (45 females, five males) who underwent posterior corrective fusion surgery for Lenke type 2 AIS with at least 2 years of follow-up were included. Radiographic parameters and health-related quality of life were evaluated preoperatively, 1 week postoperatively, and at final follow-up. Intraoperative T1 tilt and upper instrumented vertebra (UIV) tilt were measured in the prone position before and after correction. PSI was defined as radiographic shoulder height (RSH) greater than 15 mm at 1 week postoperatively. Patients were classified into PSI and non-PSI groups. Intergroup comparisons were conducted using the Mann-Whitney U test or chisquare test. Correlations of intraoperative changes in T1 tilt (ΔT1) and UIV tilt (ΔUIV) with changes in RSH (ΔRSH) and clavicle angle (ΔCA) were analyzed. Twelve patients (24.0%) had PSI at 1 week postoperatively, which persisted in five patients (10.0%) at final follow-up. Intraoperative ΔT1 and ΔUIV were significantly correlated with ΔRSH (R =0.613, p <0.001; R =0.435, p =0.002) and ΔCA (R =0.453, p =0.002; R =0.383, p =0.007). In the PSI group, ΔRSH was strongly correlated with ΔT1 (R =0.678, p =0.015). Minimizing intraoperative changes in T1 tilt may help reduce the risk of PSI in Lenke type 2 AIS.

Objective Osteoporosis is a well-known risk factor for incident vertebral fractures (VFs) and postoperative mechanical complications. However, the specific Hounsfield unit (HU) and vertebral bone quality (VBQ) cutoff values for predicting these complications, as well as the diagnostic and clinical significance of the differences between these two measurements, remain unclear. This study sought to evaluate the predictive value of HU and VBQ scores and to establish specific cutoff points for osteoporosis-related complications in lumbar spine surgery. Additionally, we analyzed whether combining HU and VBQ scores enhanced their predictive usefulness and whether the differences between them were clinically significant using principal component analysis (PCA). Methods We examined 189 patients with lumbar spinal stenosis who underwent microscopic bilateral decompression using a unilateral approach or short segmental fixation between 2010 and 2016. Patients who underwent prior lumbar surgery were excluded, and a minimum 5-year follow-up was conducted. Surgical indications were based on preoperative evaluation of segmental instability. HU values and VBQ scores were measured using computed tomography and magnetic resonance imaging, respectively. Osteoporosis-related complications, including incident VFs, and mechanical complications, such as proximal junctional fractures, cage subsidence, and screw loosening, were assessed. Results For predicting osteoporosis-related complications, cutoff points of HU < 95.5 and VBQ > 3.49 were identified, both demonstrating good predictive accuracy without a significant difference in the area under the curve. Multivariate logistic regression confirmed low HU and high VBQ as independent risk factors (adjusted odds ratio = 5.57 and 3.42, respectively; p < 0.001). Additionally, PCA revealed that the concordance of these scores significantly distinguished patients with complications from those without complications (odds ratio, 3.77; p < 0.001), while the differences between these scores lacked clinical significance. Conclusion This study demonstrated that both HU and VBQ scores effectively predicted postoperative osteoporosis-related complications, with no significant difference in predictive ability. Optimal cutoff values were identified at approximately ≤ 100 for HU and ≥ 3.5 for VBQ, and the difference between these two scores lacked clinical significance. These cut-offs for HU and VBQ can serve as practical thresholds for risk assessment, enabling spinal surgeons to use these scores as opportunistic tools for identifying patients at an elevated risk of osteoporosis-related complications after lumbar spine surgery.

Purpose The prevalence of adult spinal deformity (ASD) is expected to exceed 60 million by 2050 due to an aging population and increased life expectancy. Despite advances in surgery, high complication rates and the economic burden highlight the need for effective non-surgical treatments. This study assesses the “Koshimagari Exercise,” a self-exercise program for ASD patients, and aims to develop a classification system to identify those who would benefit most. Methods A prospective cohort study was conducted across 13 facilities, enrolling 144 participants from December 2020 to June 2022. The inclusion criteria were adults aged 50–80 years with chronic low back pain due to spinal deformities. Participants attended weekly physiotherapist-led exercise sessions and performed self-exercises at home three times a week, focusing on flexibility, functional improvement, trunk and back muscle strengthening, motor learning, and pain control. The primary outcome was the change in the Oswestry Disability Index (ODI) from baseline to 6 months post-intervention, with a 12-month follow-up. Clinical evaluations included health-related quality of life (HRQOL) assessments with ODI and EuroQol-5 Dimensions (EQ-5D), spinal alignment radiography, and magnetic resonance imaging of the paravertebral muscle (PVM) cross-sectional area. Results Of the 130 participants who provided written informed consent, 98 completed the 6-month follow-up. The study found that 42% of patients achieved a minimum clinically important difference (MCID) in ODI, with significant improvements in EQ-5D scores and LBP from baseline. Patients who achieved MCID had lower baseline body mass index and EQ-5D scores, and higher baseline ODI scores compared to those who did not. Logistic regression identified three significant predictors of MCID achievement: L4/S1 angle, the difference between standing and supine thoracolumbar kyphosis (ΔTLK), and the relative cross-sectional area (rCSA) of the PVM at L4/5. Based on these findings, a classification system was developed, dividing patients into Self-Exercise-Friendly and Self-Exercise-Limited groups, with a significant difference in ODI improvement observed between these groups at 6 months post-intervention. Conclusion The “Koshimagari Exercise,” a novel self-exercise program for ASD, achieved an MCID in the ODI for 42% of patients. The classification system, incorporating L4/S1 angle, ΔTLK, and L4/5 rCSA, is associated with improvements in HRQOL and may help identify patients who are more likely to benefit from this home-based exercise program.

Study Design: A retrospective study.Purpose: This study aimed to determine the impact of increased Hounsfield unit (HU) values for metastatic spinal lesions measured via computed tomography on the overall survival of patients with non-small-cell lung cancer (NSCLC) and identify factors associated with increased HU values in metastatic spinal lesions.Overview of Literature: Previous studies have underscored the utility of the HU as a marker of treatment response in metastatic bone lesions. However, no prior studies have explored the relationship between HU changes in response to treatment and overall survival in patients with NSCLC.Methods: This study included a total of 85 patients between 2016 and 2021. Nonsurgical treatments were provided by the respiratory medicine department. HU values for metastatic spinal lesions were evaluated upon diagnosis of spinal metastasis (baseline) and at 3, 6, and 12 months thereafter. Patients were then divided into two groups based on the median HU increase from baseline to 3 months. Overall survival was assessed using the Kaplan-Meier method.Results: Based on the median change in HU value (124), 42 and 43 patients were categorized into the HU responder and non-responder groups, respectively. The median overall survival was significantly longer in the HU responder group than in the HU non-responder group (13.7 months vs. 6.4 months, p <0.001). Multiple linear regression analysis revealed that the use of antiresorptive agents and molecularly targeted therapies were factors significantly associated with an increase in HU.Conclusions: An increase in HU values for metastatic spinal lesions after 3 months of treatment was correlated with a significantly longer overall survival in patients with NSCLC. Thus, HU measurements may not only serve as an easy and quantitative approach for evaluating treatment response in metastatic spinal lesions but also predict overall survival.

Objective Numerous studies have reported that corrective surgery improves postoperative health-related quality of life (HRQOL) in patients with adult spinal deformity (ASD), and postoperative HRQOL is maintained over 5-year follow-up. However, few studies have investigated factors associated with mid-term patient satisfaction. This study aimed to examine the factors contributing to 5-year patient satisfaction in patients with ASD following corrective surgery. Methods This study included 51 patients who underwent corrective surgery and were followed up for > 5 years postoperatively. We investigated radiographic parameters and patient-reported outcomes using the Scoliosis Research Society 22r (SRS-22r) questionnaire and 36-item Short-Form Health Survey (SF-36) preoperatively and at two postoperative time points: two years (PO2Y) and five years (PO5Y). Spearman's rank correlation analysis was used to assess the relationship between patient satisfaction at PO5Y and both radiographic parameters and HRQOL scores at PO2Y and PO5Y. Correlation between patient satisfaction at PO5Y and improvement of both radiographic parameters and HRQOL scores were also assessed. Results Patient satisfaction at PO5Y was significantly correlated with thoracic kyphosis, thoracolumbar kyphosis, and the distance between the C7-plumb line and the center of the sacral vertical line at PO2Y and PO5Y. Notably, the improvement of the function and social function domains of the SRS-22r and the SF-36, respectively, both at PO2Y and PO5Y, demonstrated a significantly weak correlation with patient satisfaction at PO5Y. Conclusion These findings underscore the significance of functional and social function improvements following corrective surgery, as they contribute to higher levels of satisfaction among patients with ASD.

Study Design: Retrospective single-center study.Purpose: This study aimed to examine the factors associated with the self-image domain of the Scoliosis Research Society-22 revised (SRS-22r) in patients who underwent corrective surgery for adult idiopathic scoliosis (AdIS).Overview of Literature: Adult spinal deformity (ASD) can be classified into AdIS and de novo scoliosis. However, no studies have investigated the effect of different ASD pathologies on self-image.Methods: This study enrolled 60 patients who underwent corrective surgery and were followed up for >2 years postoperatively. AdIS was defined as adolescent idiopathic scoliosis in patients who had no history of corrective surgery, had a primary thoracolumbar/lumbar (TL/L) curve, and were ≥30 years old at the time of surgery.Results: The AdIS (n=23; mean age, 53.1 years) and de novo (n=37; mean age, 70.0 years) groups were significantly different in terms of the main thoracic and TL/L curves, sagittal vertical axis, thoracic kyphosis, and thoracolumbar kyphosis preoperatively. The scores in the self-image domain of the SRS-22r (before surgery/2 years after surgery [PO2Y]) were 2.2/4.4 and 2.3/3.7 in the AdIS and de novo groups, respectively, and PO2Y was significantly different between the two groups (p<0.001). Multivariate regression analysis revealed that AdIS was an independent factor associated with self-image at PO2Y (p=0.039).Conclusions: AdIS, a spinal deformity pathology, was identified as a significant factor associated with the self-image domain of SRS-22r in patients who underwent corrective surgery. AdIS is not solely classified based on pathology but also differs in terms of the clinical aspect of self-image improvement following corrective surgery.

Study Design.: Retrospective cohort study. Objective.: To assess the utility of preoperative vertebral bone quality (VBQ) scores in predicting the 5-year clinical outcomes following lumbar spine surgery. Summary of Background Data.: Osteoporosis poses a significant concern in older adults undergoing spinal surgery. The VBQ score, assessed through preoperative magnetic resonance imaging (MRI), is associated with subsequent osteoporotic fractures and postoperative complications. However, previous report on the impact of VBQ score on mid-term clinical outcomes after lumbar spine surgery remains lacking. Methods.: A total of 189 patients who underwent lumbar surgery (≤3-disc levels) for lumbar spinal stenosis between 2010 and 2016 were enrolled. Patients were classified into high (>3.35), middle (2.75 to 3.35), and low (P=0.013), walking ability (P=0.005), social life function (P=0.010) of JOABPEQ, and physical component summary of the SF-36 (P=0.018) following lumbar spine surgery. A higher VBQ score was significantly correlated with worse 5-year postoperative outcomes for all domains except for lumbar function of the JOABPEQ using multiple linear regression analysis, adjusting for age, sex, BMI, hyperlipidemia, surgical procedures, and each preoperative score. Conclusion.: A high preoperative VBQ score is a risk factor for poor 5-year clinical outcomes after lumbar spine surgery. Evaluation of the VBQ score through routine preoperative MRI facilitates osteoporotic screening in lumbar patients without radiation exposure and healthcare costs, while also demonstrating its potential as a prognostic indicator of postoperative clinical outcomes. Level of Evidence.: 3