Is Orthotic Treatment Beneficial for Fresh Osteoporotic Vertebral Fractures? A Propensity Score Matching Study.

BACKGROUND CONTEXT: Orthotic treatment is a common option for the conservative treatment of osteoporotic vertebral fractures (OVF). However, there is insufficient evidence of its clinical benefit. PURPOSE: To investigate the effectiveness of orthotic treatment for OVF. STUDY DESIGN/SETTING: Retrospective cohort study with data from two prospective studies. PATIENT SAMPLE: This study included 160 patients with fresh OVF enrolled in 2012 and 2020 prospective cohort studies. OUTCOME MEASURES: The visual analog scale (VAS) score for low back pain was used for clinical outcomes, and radiographic parameters included the percent height of the vertebra and angular change of the vertebral body. Moreover, the occurrence of secondary vertebral fractures was followed-up over time. METHODS: The patients were divided into brace and no-brace groups and were matched according to propensity score for age, sex, anterior percent height at the initial examination, and presence of old OVFs. Hazard ratio for the cumulative incidence of secondary vertebral fractures with and without bracing were calculated and analyzed using the generalized Wilcoxon test. In addition, the brace group was divided into soft and rigid brace groups and compared with the no-brace group. RESULTS: Each group had 61 cases after propensity score matching. There were no significant differences in the VAS improvement for low back pain and the change in percent height of the anterior and posterior walls from initial examination to 6 months after injury (p = 0.87, p = 0.39 and p = 0.14, respectively, mixed-effect models). Meanwhile, the mean angular change of fractured vertebrae was 4.3° / 3.2° initially and 1.2° / 2.5° at 6 months (the brace group / no-brace group, respectively; p = 0.007, mixed-effect models). A significant difference was also observed between the rigid brace group and the no-brace group (p = 0.008, mixed effect models). The incidence of secondary vertebral fractures was 1.6% / 11.4% at 1 month, indicating a significant difference (the brace group / no-brace group, respectively; p = 0.028). The hazard ratio for the cumulative incidence of secondary fractures due to orthotic treatment was 0.47 (95% confidence interval 0.20-1.09, p = 0.054). CONCLUSIONS: Although orthotic treatment for fresh OVF did not relieve pain, it might contribute to the stabilization of the fractured vertebra, especially using a rigid brace. Moreover, it might influence a reduction of the imminent vertebral fracture risk immediately after the onset of OVF. CLASSIFICATIONS: Clinical study.

Clinical Comparison of Combined Cortical Bone Trajectory and Transarticular Surface Screw Versus Standard Pedicle Screw Insertion by Wiltse Approach for L5 Isthmic Spondylolisthesis.

STUDY DESIGN: This was a retrospective cohort study. OBJECTIVE: The objective of this study was to assess the effectiveness and invasiveness of a combined screw insertion technique [using cortical bone trajectory (CBT) screw and transarticular surface screw (TASS)] for patients with L5 isthmic spondylolisthesis. SUMMARY OF BACKGROUND DATA: Lumbosacral posterior fixation using TASS is safe, with high biomechanical strength. However, data regarding its clinical outcomes, effectiveness, and invasiveness, are lacking. MATERIALS AND METHODS: This study included 111 patients who underwent single-level L5-S1 posterior lumbar interbody fusion (PLIF) for L5 isthmic spondylolisthesis. The cohort was stratified into 2 groups: the Wiltse group included patients who underwent PLIF between 2008 and 2013 with standard pedicle screw fixation via Wiltse approach and the CBT/TASS group included those who underwent PLIF from 2014 onward with CBT/TASS fixation. After propensity score matching of the CBT/TASS and Wiltse groups, the surgical times, estimated blood loss (EBL), length of in-hospital stays, clinical scores, serum creatine kinase concentration, radiographic parameters, and bone union rate were compared using the χ2 test or Mann-Whitney U test. In addition, multivariate linear regression analyses, with surgical time and EBL as objective variables applied after Box-Cox transformation, were performed. RESULTS: The matched CBT/TASS group showed significantly shorter surgical times (P<0.001), lower EBL (P=0.032), shorter in-hospital stays (P=0.005), and lower 3-day postoperative serum creatine kinase concentrations (P=0.014) than the matched Wiltse group. However, neither the postoperative grade of spondylolisthesis, the L5-S1 lordotic angle, nor the clinical scores were significantly different between matched groups. The bone union rates were 94.7% and 96.2% in the matched CBT/TASS and Wiltse groups, respectively (P=1.000). Regression analysis showed that CBT/TASS was an independent factor significantly related to shorter surgical times and lower EBL (P<0.001 and P=0.001, respectively). CONCLUSION: Compared with Wiltse approach, CBT/TASS is a less invasive technique, with a shorter surgical time and sufficient clinical outcomes for patients with L5 isthmic spondylolisthesis. LEVEL OF EVIDENCE: Level III-treatment benefits.

Validity and Reproducibility of Various Measurement Methods for Craniocervical Sagittal Balance.

STUDY DESIGN: A cross-sectional study. OBJECTIVE: To identify the best indicator for reproducible representation of craniocervical sagittal balance (CCSB). SUMMARY OF BACKGROUND DATA: Spinal sagittal balance is considered one of the most critical factors affecting the health-related quality of life. Although standard indicators of spinopelvic balance have been established, these do not include the craniocervical balance and there is no standard parameter for evaluating the CCSB. MATERIALS AND METHODS: Six kinds of sagittal vertical axis (SVA) were drawn by a total of 9 spine or orthopedic surgeons, from the anterior margin of the external auditory canal: cranial center of gravity (CCG), C1 (center of the anterior arch), C2 (C2vb: center of the vertebral body, C2e: center of the lower endplate), and C7 (C7vb: center of the vertebral body, C7p: posterosuperior corner). Eight SVA distances were measured by using 30 radiographs; CCG-C7vb, C1-C7vb, C2e-C7vb, C2vb-C7vb, CCG-C7p, C1-C7p, C2e-C7p, and C2bv-C7p.The interobserver and intraobserver reliabilities, and the correlations between CCG and C1, C2e, or C2bv were calculated among the main groups or subgroups. RESULTS: In the overall analysis, although the intraclass correlation coefficients (ICC) (1, 1) of all parameters were >0.900, the ICC (2, 1) of CCG-C7p and CCG-C7vb were <0.900. The same trends were noted in the subgroups based on observer's experience. Comparing C7p-related and C7vb-related parameters, ICC (2, 1) showed 0.901 in C7p-related and 0.849 in C7bv-related parameters. In the analysis of the correlation between cranial SVAs, C1-C7p and C2vb-C7p SVAs correlated highly with CCG-C7p SVA (0.905, 0.805, respectively). CONCLUSIONS: Although the CCG SVA represents the center of the head, the current results revealed its low reproducibility. The low values were notable in those unfamiliar with craniocervical anatomy. The correlation analysis indicated that C1-C7p and C2vb-C7p SVA parameters are suitable for CCG-C7p SVA. Therefore, these 2 are considered as possible standard parameters in evaluating CCSB. LEVEL OF EVIDENCE: Level III.

Tumor accumulation of ε-poly-lysines-based polyamines conjugated with boron clusters.

Boron Neutron Capture Therapy (BNCT) is one of the potent cancer radiotherapies using nuclear reaction between (10)B atoms and the neutron. Whether BNCT will succeed or not depends on tumor selective delivery of (10)B compounds. ε-Poly-L-lysine is a naturally occurring polyamine characterized by the peptide linkages between the carboxyl and ε-amino groups of L-lysine. Because of high safety ε-PLL is applied practically as a food additive due to its strong antimicrobial activity. In this study, we focus on a development of a novel polymeric delivery system for BNCT using biodegradable ε-PLL conjugated with (10)B-containing clusters (BSH). This polymeric boron carrier will be expected to deliver safely and efficiently into tumor tissues based on Enhanced Permeability and Retention (EPR) effect.