Methods: This study included 138 patients who underwent PLIF, with a mean age of 67 years and a follow-up period of 12 months. At 12 months postoperatively, lumbar computed tomography (CT) was performed to assess SL, and patients were categorized into SL and nonloosening (NL) groups accordingly. A propensity score-matched model was used to adjust for age, sex, and body mass index (BMI). Propensity score matching was performed to compare outcomes between the SL and NL groups. Results: Among the 138 patients, 29 (21%) developed SL following PLIF. Preliminary analysis revealed that the patients in the SL group were older and exhibited decreased femoral neck bone mineral density, preoperative pelvic retroversion, poor whole spine alignment, and lesser improvement in HRQOL compared with the NL group. Using propensity score matching, 22 patients were selected from each group (mean age, 72 years) (C-statistic=0.78). The propensity score-matched analysis demonstrated significant differences in the preoperative pelvic tilt (25.9° vs. 17.8°, p=0.010) between the matched SL and NL groups. Furthermore, the Oswestry Disability Index scores indicated poorer improvements in the matched SL group than in the matched NL group at 9 months postoperatively (p=0.025). Conclusions After matching, pre- and postoperative pelvic retroversion were significantly associated with SL. Patients with SL experienced significantly poorer improvement in HRQOL at 9 months postoperatively. Therefore, implementing strategies for preventing SL may enhance early postoperative HRQOL.

Objective: This study compared the mechanical properties of two self-expanding nitinol tracheal stents with different braided patterns—a conventional cross-braided design and a cross-and-hook braided design—to assess their mechanical characteristics and potential suitability for use in dogs. Methods: Mechanical testing was performed on two commercial veterinary tracheal stents: a cross-braided stent and a cross-and-hook braided stent (Fauna stent; M.I.TECH. Co. Ltd, Korea).The flexural stiffness was assessed using a three-point bending test, while the radial and axial mechanical strengths were evaluated using compression and tensile tests, respectively. Results: The cross-and-hook braided stent showed greater bending flexibility and slightly higher radial stiffness than the cross-braided stent. Both stents showed comparable tensile resistance within the physiological deformation ranges. The cross-and-hook structure also retained its cell geometry under compression and resisted permanent deformation more effectively. Conclusions and Relevance: The cross-and-hook braided stent showed trends toward improved mechanical properties relevant to the clinical performance in dogs, with possible benefits in reducing stent fatigue and rupture. These findings highlight its potential suitability for managing tracheal collapse in dogs and may help guide future development of veterinary and human stents.

Methods: We included 237 participants from a 2-yearly resident health checkup conducted in Toei, Aichi, Japan. Participants underwent blood tests and whole-spine standing radiography, and were stratified based on age (60s, 70s, and 80s) and sex to determine age-specific normative PNI values. Additionally, participants were categorized into a lower PNI (PNI <50) or higher PNI (PNI ≥50) group to compare spinal alignment. Results: The average PNI values for different age groups were: 60s: males (n=13): 50.7, females (n=31): 50.9; 70s: males (n=55): 50.3, females (n=57): 50.1; 80s: males (n=28): 49.1, females (n=53): 48.3. For females, the radiographic spinal alignment parameters were comparable between the lower and higher PNI groups; however, in males, significant differences were noted for pelvic tilt (20° vs. 16°, p=0.020), lumbar lordosis (35° vs. 44°, p<0.001), and pelvic incidence minus lumbar lordosis (10° vs. 4°, p=0.013). Conclusions Malnutrition in males negatively impacts their lumbar-pelvic alignment. While the normative PNI value decreases with age, the two variables show a very weak correlation.

Methods: Radiological parameters were extracted from the whole lateral radiographs. Patients were divided into two groups: the ASD group (segmental kyphosis of ≥10º, and/or a ≥50% loss of disc height, and/or ≥3 mm of anteroposterior translation) and the non-ASD group. Results: All 112 included patients underwent PLIF for lumbar degenerative diseases. The minimum follow-up period was 2 years, with an average follow-up time of 63.6 months. Fifty-two patients (46.4%) were classified into the ASD group and of these, 13 required reoperation due to failure of conservative treatment. Patients with ASD exhibited significantly more caudal and posterior inflection vertebrae (IV), while the lumbar apical vertebra was significantly more caudal immediately after surgery. The IV position was identified as a significant risk factor for ASD, and the ASD incidence was significantly higher in the group where IV ≤5 (L1 vertebral body) than in the group where IV ≥5.5 (T12–L1 disc) (69.0% vs. 38.6%). Conclusions The IV position is a significant risk factor for ASD development. Although it is difficult to control intraoperative IV levels, we note a high risk of ASD in patients with IV lower than T12–L1.

Objectives: Locomotive syndrome stage 3 (LS3), which has been established recently, may imply a greater need for care than LS stage 0 (LS0), LS stage 1 (LS1), and LS stage 2 (LS2). The relationship between LS3 and long-term care in Japan is unclear. Therefore, this study aimed to examine this relationship. Methods: A total of 531 patients (314 women and 217 men; mean age, 75 years) who were not classified as requiring long-term care and underwent musculoskeletal examinations in 2012 were grouped according to their LS stage. Group L comprised patients with LS3 and Group N comprised those with LS0, LS1, and LS2. We compared these groups according to their epidemiology results and long-term care requirements from 2013 to 2018. Results: Fifty-nine patients (11.1%) were diagnosed with LS3. Group L comprised more patients (50.8%) who required long-term care than Group N (17.8%) (P < 0.001). Group L also comprised more patients with vertebral fractures and knee osteoarthritis than Group N (33.9% vs 19.5% [P = 0.011] and 78% vs 56.4% [P < 0.001], respectively). A Cox proportional hazards model and Kaplan–Meier analysis revealed a significant difference in the need for nursing care between Groups L and N (log-rank test, P < 0.001; hazard ratio, 2.236; 95% confidence interval, 1.451–3.447). Conclusions Between 2012 and 2018, 50% of patients with LS3 required nursing care. Therefore, LS3 is a highrisk condition that necessitates interventions. Approaches to vertebral fractures and osteoarthritis of the knee could be key.

This paper reports the clinical findings and surgical treatment of feline right patent ductus arteriosus (RPDA) with a left aortic arch. A two-month-old female Maine Coon was referred for an investigation of regurgitation after weaning. RPDA with a left aortic arch was diagnosed based on the echocardiographic and computed tomography (CT) findings.A right-fourth intercostal thoracotomy was found to be an appropriate approach to the duct. Preoperative diagnosis is crucial and diagnostic imaging, including radiography, echocardiography, and cardiac CT examination, is essential for determining if the aortic arch is right or left.

Methods: This retrospective study includes 295 corrective surgery patients with ASD. Subjects were divided into two groups after propensity age matching analysis: cranial malalignment (McGS <−8 or >13) and normal cranial alignment (−8≤ McGS ≤13). Lumbar lordosis (LL), pelvic tilt (PT), TK, cervical lordosis (CL), and sagittal vertical axis (SVA) were evaluated between the two groups. Results: SVA (95–56 mm) and PT (34°–25°) decreased and LL (19°–41°) increased 2 years after surgery (p <0.05), but McGS (−1.1° to −0.5°) and CL (21°–19°) did not change. Conversely, in the group with cranial malalignment, SVA (120–64 mm), PT (35°–26°), and LL (12°–41°) showed similar results to the normal cranial parameter group 2 years after surgery, but in contrast, McGS (−13° to −2°) and CL (24°–18°) improved significantly. Conclusions Severe ASD adversely affects to maintain horizontal gaze but can be improved by spinal corrective surgery.

Methods: Adult volunteers aged over 50 years were included in the study after participating in the screening program. Characteristic data and standing radiographic parameters were assessed. A propensity score model was established with adjustments for age and sex after a preliminary analysis, and cases were divided into DLS (Cobb angle >10°) and non-DLS (Cobb angle ≤10°) groups. Results: There were significant differences in age, sex, C2 sagittal vertical axis (C2-SVA), C7-SVA, T1 pelvic angle (TPA), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), PI minus LL (PI–LL), knee angle, ankle angle, pelvic shift, C7-center sacral vertical line, L4 tilt, femur-tibia angle, and hip-knee-ankle angle (all p <0.05) using a preliminary analysis of 261 cases (75 DLS and 186 non-DLS). A one-to-one propensity score-matched analysis was used after 70 pairs of cases were selected. There were no significant differences in the characteristic data for lower extremity parameters. There were still significantly higher values of C2-SVA, TPA, PI, PT, and PI–LL in DLS group than in non-DLS group (all p <0.05). Conclusions This study showed an important relationship between DLS and sagittal spinal deformity. However, DLS was not associated with the sagittal and coronal lower extremity alignments.

Methods: We examined the data of AIS patients with Lenke type 1 curves who underwent posterior fusion surgery in a retrospective manner. PSI was defined as a 2-year postoperative absolute radiographic shoulder height (RSH) of ≥2 cm. Patients were divided into two groups based on the presence of PSI and the level of their upper instrumented vertebra (UIV) (UIV at T2 or T3 [U-UIV] or UIV below T3 [L-UIV]). The radiographic parameters and clinical outcomes were compared, and the cutoff values of risk factors were identified by multivariate analysis. Results: Of 104 patients, 21 (20.2%) had left shoulder elevation PSI. The PSI group had a significantly greater preoperative RSH (−5.1 mm vs. −14.3 mm) and main thoracic (MT) curve correction rate (77.3% vs. 69.1%) than the non-PSI group. The PSI incidence did not differ between the U-UIV and L-UIV groups. Multivariate analysis identified preoperative RSH and the MT curve correction rate as independent risk factors for PSI. The receiver operating characteristic curve analysis identified the preoperative RSH cutoff value as −6.5 mm and MT curve correction rate cutoff value as 76.9%. Conclusions Even in AIS patients with Lenke type 1 curves, the incidence of PSI was relatively high (20.2%). Patients with preoperative lower right shoulder elevation (i.e., RSH >−6.5 mm) had a higher risk of PSI regardless of UIV level when the MT curve showed a higher correction rate (i.e., correction rate >76.9%).

Methods: This study prospectively examined nine T-OPLL patients who underwent posterior thoracic decompression with kyphosis correction and instrumented fusion at Hamamatsu University School of Medicine between 2017 and 2019. All underwent preoperative selective angiography to detect and evaluate the Adamkiewicz artery and ASA. Intraoperative neuromonitoring and Doppler ultrasonography were performed to analyze neurological complications and spinal cord blood flow. Results: All nine patients showed ASA stenosis in the area of T-OPLL. In all patients, the Adamkiewicz artery was located between T7 and L2 and the area of ASA stenosis corresponded to the level of T-OPLL and greatest spinal cord compression; intraoperative Doppler ultrasonography confirmed the ASA defect at the same spinal level. The number of spinal levels from the Adamkiewicz artery to the most compressive OPLL lesion was greater in the two patients who developed postoperative neurological deficit compared to those who did not (5.5 vs. 2.3, p=0.014). Conclusions This is the first study to report detection of ASA stenosis in patients with T-OPLL. Maintaining spinal cord blood flow is important in these patients to avoid neurological deterioration.