Background and Objectives: Bone metastasis cancer boards (BMCBs) focusing on the management of bone metastases have been gathering much attention. However, the association of BMCBs with spinal surgery in patients with spinal metastases remains unclear. In this retrospective single-center observational study, we aimed to clarify the effect of a BMCB on spinal metastasis treatment. Materials and Methods: We reviewed consecutive cases of posterior decompression and/or instrumentation surgery for metastatic spinal tumors from 2008 to 2019. The BMCB involved a team of specialists in orthopedics, rehabilitation medicine, radiation oncology, radiology, palliative supportive care, oncology, and hematology. We compared demographics, eastern cooperative oncology group performance status (ECOGPS), Barthel index (BI), number of overall versus emergency surgeries, and primary tumors between patients before (2008–2012) and after (2013–2019) BMCB establishment. Results: A total of 226 patients including 33 patients before BMCB started were enrolled; lung cancer was the most common primary tumor. After BMCB establishment, the mean patient age was 5 years older (p = 0.028), the mean operating time was 34 min shorter (p = 0.025), the mean hospital stay was 34.5 days shorter (p < 0.001), and the mean BI before surgery was 12 points higher (p = 0.049) than before. Moreover, the mean number of surgeries per year increased more than fourfold to 27.6 per year (p < 0.01) and emergency surgery rates decreased from 48.5% to 29.0% (p = 0.041). Patients with an unknown primary tumor before surgery decreased from 24.2% to 9.3% (p = 0.033). Postoperative deterioration rates from 1 to 6 months after surgery of ECOGPS and BI after BMCB started were lower than before (p = 0.045 and p = 0.027, respectively). Conclusion: The BMCB decreased the emergency surgery and unknown primary tumor rate despite an increase in the overall number of spinal surgeries. The BMCB also contributed to shorter operation times, shorter hospital stays, and lower postoperative deterioration rates of ECOGPS and BI.

Aims: Continuous local antibiotic perfusion (CLAP) has recently attracted attention as a new drug delivery system for orthopaedic infections. CLAP is a direct continuous infusion of high-concentration gentamicin (1,200 μg/ml) into the bone marrow. As it is a new system, its influence on the bone marrow is unknown. This study aimed to examine the effects of high-concentration antibiotics on human bone tissue-derived cells.Methods: Cells were isolated from the bone tissue grafts collected from six patients using the Reamer-Irrigator-Aspirator system, and exposed to different gentamicin concentrations. Live cells rate, apoptosis rate, alkaline phosphatase (ALP) activity, expression of osteoblast-related genes, mineralization potential, and restoration of cell viability and ALP activity were examined by in vitro studies.Results: The live cells rate (the ratio of total number of cells in the well plate to the absorbance-measured number of live cells) was significantly decreased at ≥ 500 μg/ml of gentamicin on day 14; apoptosis rate was significantly increased at ≥ 750 μg/ml, and ALP activity was significantly decreased at ≥ 750 μg/ml. Real-time reverse transcription-polymerase chain reaction results showed no significant decrease in the ALP and activating transcription factor 4 transcript levels at ≥ 1,000 μg/ml on day 7. Mineralization potential was significantly decreased at all concentrations. Restoration of cell viability was significantly decreased at 750 and 1,000 μg/ml on day 21 and at 500 μg/ml on day 28, and ALP activity was significantly decreased at 500 μg/ml on day 28.Conclusion: Our findings suggest that the exposure concentration and duration of antibiotic administration during CLAP could affect cell functions. However, further in vivo studies are needed to determine the optimal dose in a clinical setting.Cite this article: Bone Joint Res 2024;13(3):91–100.

The Masquelet technique is a relatively new method for large bone defect treatment. In this technique, grafted bone tissue is used, and after the cement is removed, the induced membrane (IM; that form around the cement spacers placed in the bone defect region) is thought to play an important role in promoting bone formation. On the other hand, low-intensity pulsed ultrasound (LIPUS) is known to promote fracture healing and angiogenesis through mechanical stimulation. This study aimed to investigate the in vitro effects of LIPUS on the osteogenic differentiation of human induced membrane-derived cells (IMCs). Seven patients who had been treated using the Masquelet technique were enrolled. The IM was harvested during the second stage of the technique. IMCs were isolated, cultured in growth medium, and then divided into two groups: (1) control group, IMCs cultured in osteogenic medium without LIPUS, and (2) LIPUS group, IMCs cultured in osteogenic medium with LIPUS treatment. Adherent cells from the IM samples were harvested after the first passage and evaluated for cell surface protein expression using immunostaining. A cell proliferation assay was used to count the number of IMCs using a hemocytometer. Osteogenic differentiation capability was assessed using an alkaline phosphatase (ALP) activity assay, Alizarin Red S staining, and real-time reverse transcription-polymerase chain reaction. Cell surface antigen profiling revealed that the IMCs contained cells positive for the mesenchymal stem cell-related markers CD73, CD90, and CD105. No significant difference in cell numbers was found between the control and LIPUS groups. The ALP activity of IMCs in the LIPUS group was significantly higher than that in the control group on days 7 and 14. Alizarin red S staining intensity was significantly higher in the LIPUS group than in the control group on day 21. Runx2 and VEGF expression was significantly upregulated on days 7 and 14, respectively, compared with levels in the control group. We demonstrated the significant effect of LIPUS on the osteogenic differentiation of human IMCs. This study indicates that LIPUS can be used as an additional tool for the enhancement of the healing process of the Masquelet technique.

Background and Objectives: Changes in activities of daily living (ADL) and quality of life (QOL) of patients with bone metastasis who underwent surgical treatment through Bone Metastasis Cancer Boards (BMCBs), a recent multidisciplinary approach for managing bone metastases, have been reported; however, no reports exist on patients who undergo conservative treatment. In this study, we aimed to evaluate these patients’ ADL and QOL and examine the factors influencing changes in these parameters. Materials and Methods: We retrospectively reviewed 200 patients with bone metastases who underwent conservative therapy through BMCBs between 2013 and 2021. A reassessment was conducted within 2–8 weeks after the initial assessment. Patients’ background and changes in performance status (PS), Barthel Index (BI), EuroQol five-dimension (EQ-5D) scores, and Numerical Rating Scale (NRS) scores were initially assessed. Furthermore, we categorized patients into two groups based on improvements or deteriorations in ADL and QOL and performed comparative analyses. Results: Significant improvements in EQ-5D (0.57 ± 0.02 versus [vs.] 0.64 ± 0.02), NRS max (5.21 ± 0.24 vs. 3.56 ± 0.21), and NRS average (2.98 ± 0.18 vs. 1.85 ± 0.13) scores were observed between the initial assessment and reassessment (all p < 0.001). PS (1.84 ± 0.08 vs. 1.72 ± 0.08) and BI (83.15 ± 1.68 vs. 84.42 ± 1.73) also showed improvements (p = 0.06, and 0.054, respectively). In addition, spinal cord paralysis (odds ratio [OR]: 3.69, p = 0.049; OR: 8.42, p < 0.001), chemotherapy (OR: 0.43, p = 0.02; OR: 0.25, p = 0.007), and NRS average scores (OR: 0.38, p = 0.02; OR: 0.14, p < 0.001) were independent factors associated with ADL and QOL. Conclusions: Patients with bone metastases who underwent conservative treatment through BMCBs exhibited an increase in QOL without a decline in ADL. The presence of spinal cord paralysis, absence of chemotherapy, and poor pain control were associated with a higher risk of deterioration in ADL and QOL.

Aims: Phase angle (PhA)—a parameter of bioelectrical impedance analysis—is known to reflect cellular nutritional status and cell membrane integrity and is commonly used as an indicator of muscle quality. This study aimed to explore the association between PhA and exercise capacity and to determine the potential of the former as a novel predictor of the latter in patients undergoing late-recovery phase cardiac rehabilitation (CR). Methods and results: This retrospective study included 107 patients undergoing CR. Phase angle was measured via bioelectrical impedance analysis, and peak oxygen consumption (V̇O2) was determined via cardiopulmonary exercise testing before and after CR. Furthermore, correlation and multiple regression analyses were conducted to identify the associations between PhA, peak V̇O2, and other clinical parameters, such as age, sex, grip strength, skeletal muscle index (SMI), Geriatric Nutritional Risk Index (GNRI), and N-terminal pro-B-type natriuretic peptide (NT-pro-BNP). Phase angle markedly increased after CR in men and women (4.69–4.89 and 4.06–4.47, respectively; P < 0.05 for both). Notably, PhA exhibited a strong correlation with pre- and post-peak V̇O2, with a notably stronger correlation observed after CR (r = 0.603, P < 0.01). Multiple regression analysis revealed that PhA was an independent predictor of peak V̇O2 even after adjusting for confounding factors, such as age, sex, grip strength, SMI, GNRI, and NT-pro-BNP. Conclusion: This study is the first to provide evidence of the significant correlation between PhA and exercise capacity in patients undergoing the late-recovery phase of CR. Phase angle was found to be a reliable predictor of exercise capacity and holds promise as a novel biomarker for optimizing CR interventions and potentially improving patient outcomes.

This study compared the predictive validity of three-dimensional joint space width (3D-JSW) on weight-bearing computed tomography (WBCT) versus two-dimensional joint space width at predetermined mediolateral locations (2D-JSW_x) on radiographs for worsening knee pain and physical function over 24 months. Data from 302 participants (425 knees) in the Multicenter Osteoarthritis Study (MOST) were analyzed. Baseline assessments included bilateral standing radiographs for 2D-JSW_x and WBCT for 3D-JSW. Minimal clinically important worsening (MCIW) of pain (Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale) and function (20-m walk, sit-to-stand, WOMAC function subscale) over 24 months was assessed. Logistic regression with generalized estimating equations (GEE) accounted for within-person correlation, and predictive validity was evaluated by comparing receiver operating characteristic (ROC) areas under the curves (AUC). Participants had a mean age of 63.2±8.9 years and body mass index (BMI) of 28.2±4.8 kg/m². Over 24 months, 38 knees exhibited worsening WOMAC pain, with no significant association for either 3D-JSW or 2D-JSW_x. For WOMAC pain, 3D-JSW (AUC=0.578) was not superior to 2D-JSW_x (AUC=0.511; difference: 0.067 (95% confidence interval (CI): -0.040, 0.175)). Similar results were noted for the 20-m walk (difference: 0.003 (95% CI: -0.049, 0.055)), sit-to-stand test (difference: 0.014 (95% CI: -0.034, 0.062)), and WOMAC function (difference: -0.020 (95% CI: -0.091, 0.050)). 3D-JSW on WBCT did not outperform 2D-JSW_x on radiography for predicting knee pain and functional worsening. However, WBCT offers several advantages, including improved imaging capabilities, that may facilitate assessment of osteoarthritis in clinical practice and research.