Mer tyrosine kinase regulates bone metabolism, and its deficiency partially ameliorates periodontitis- and ovariectomy-induced bone loss in mice.

Bone homeostasis is maintained by tightly coordinated activities of bone-forming osteoblasts and bone-resorbing osteoclasts. In the present report, the role of Mer tyrosine kinase (MerTK) in bone metabolism was investigated. The expression of MerTK decreased upon BMP2 stimulation of osteoblast precursors. The femurs of Mertk-deficient mice showed significantly increased bone volume with concomitant increase of bone formation and reduction in bone resorption. These bone phenotypes were attributed to the increased osteoblast differentiation and mineralization accounted by the enhanced ß-catenin and Smad signaling in the absence of MerTK in osteoblast precursors. Although the Mertk-deficient bone marrow macrophages were predisposed to enhanced osteoclast differentiation via augmented Ca2+-NFATc1 signaling, the dramatic increase of Tnfsf11b/Tnfsf11 (Opg/Rankl) ratio in Mertk knockout bones and osteoblast precursors corroborated the reduction of osteoclastogenesis in Mertk deficiency. In ligature-induced periodontitis and ovariectomy models, the bone resorption was significantly attenuated in Mertk-deficient mice compared with wild-type control. Taken together, these data indicate novel role of MerTK in bone metabolism and suggest a potential strategy targeting MerTK in treating bone-lytic diseases including periodontitis and osteoporosis.

Treatment of Osteoporosis after Hip Fracture: Survey of the Korean Hip Society.

Purpose: To assess current practice in the treatment of osteoporosis in patients who underwent treatment for hip fracture in South Korea. Materials and Methods: A survey of 97 members of the Korean Hip Society, orthopedic hip surgeons who administer treatment for hip fractures in South Korea, was conducted. The survey was conducted for assessment of demographic data and perceptions regarding the management of osteoporosis in patients who have undergone treatment for hip fracture. Analysis of the data was performed using descriptive statistical methods. Results: The majority of participants were between the age of 41 and 50 years, and 74% were practicing in tertiary hospitals. Testing for serum vitamin D levels (82%) was the most commonly performed laboratory test. Calcium and vitamin D were prescribed for more than 80% of patients by 47% and 52% of participants, respectively. Denosumab was the most commonly used first-line treatment option for osteoporosis in hip fracture patients. Bisphosphonate was most often perceived as the cause of atypical femoral fractures, and the most appropriate time for reoperation was postoperative 12 months. Teriparatide was most preferred after cessation of bisphosphonate and only prescribing calcium and vitamin D was most common in high-risk patients for prevention of atypical femoral fracture. Conclusion: The results of this study that surveyed orthopedic hip surgeons showed that most participants followed the current strategy for management of osteoporosis. Because the end result of osteoporosis is a bone fracture, active involvement of orthopedic surgeons is important in treating this condition.

Optimization of Acetabular Cup Abduction by Adjusting Pelvic Pitch.

Background: The purposes of this study were to determine the accuracy of our cup positioning method and to evaluate the dislocation rate after total hip arthroplasty (THA). Methods: After positioning the patient in the lateral decubitus position on the operation table, an anteroposterior view of the hip was taken. The pelvic pitch was measured on the X-ray. A positive pitch was defined as the caudal rotation of the upper hemipelvis. Our target abduction of the cup was 43°. We used the cup holder to guesstimate the cup abduction. In a preliminary study, we found that the weight of the cup holder increased the pelvic pitch by 5°. Thus, the target abduction of the cup holder was calculated by a formula: 43° - pelvic pitch - 5°. During the cup insertion, the cup holder was anteverted to the calculated target according to the concept of combined anteversion. We evaluated 478 THAs (429 patients), which were done with the use of the method. Results: The mean cup abduction was 43.9° (range, 32.0°-53.0°) and the mean error of cup abduction was 2.4° (standard deviation [SD], 2.0°; range, 0.0°-11.0°). The mean cup anteversion was 28.5° (range, 10.0°-42.0°) and the mean error of cup anteversion was 6.7° (SD, 5.2°; range, 0.0°-27.6°). Of all, 82.4% of the cups (394 / 478) were within the safe zone: 30°-50° abduction and 10°-35° anteversion. During 2- to 5-year follow-up, no hip dislocated. Conclusions: Our adjusting method according to the pelvic pitch can be a reliable option for optimizing the cup abduction in THA.

A CT-based Deep Learning Model for Predicting Subsequent Fracture Risk in Patients with Hip Fracture.

Background Patients have the highest risk of subsequent fractures in the first few years after an initial fracture, yet models to predict short-term subsequent risk have not been developed. Purpose To develop and validate a deep learning prediction model for subsequent fracture risk using digitally reconstructed radiographs from hip CT in patients with recent hip fractures. Materials and Methods This retrospective study included adult patients who underwent three-dimensional hip CT due to a fracture from January 2004 to December 2020. Two-dimensional frontal, lateral, and axial digitally reconstructed radiographs were generated and assembled to construct an ensemble model. DenseNet modules were used to calculate risk probability based on extracted image features and fracture-free probability plots were output. Model performance was assessed using the C index and area under the receiver operating characteristic curve (AUC) and compared with other models using the paired t test. Results The training and validation set included 1012 patients (mean age, 74.5 years ± 13.3 [SD]; 706 female, 113 subsequent fracture) and the test set included 468 patients (mean age, 75.9 years ± 14.0; 335 female, 22 subsequent fractures). In the test set, the ensemble model had a higher C index (0.73) for predicting subsequent fractures than that of other image-based models (C index range, 0.59-0.70 for five of six models; P value range, < .001 to < .05). The ensemble model achieved AUCs of 0.74, 0.74, and 0.73 at the 2-, 3-, and 5-year follow-ups, respectively; higher than that of most other image-based models at 2 years (AUC range, 0.57-0.71 for five of six models; P value range, < .001 to < .05) and 3 years (AUC range, 0.55-0.72 for four of six models; P value range, < .001 to < .05). Moreover, the AUCs achieved by the ensemble model were higher than that of a clinical model that included known risk factors (2-, 3-, and 5-year AUCs of 0.58, 0.64, and 0.70, respectively; P < .001 for all). Conclusion In patients with recent hip fractures, the ensemble deep learning model using digital reconstructed radiographs from hip CT showed good performance for predicting subsequent fractures in the short term. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Li and Jaremko in this issue.

PINK1 restrains periodontitis-induced bone loss by preventing osteoclast mitophagy impairment.

The oral colonization of periodontal pathogens onto gingival tissues establishes hypoxic microenvironment, often disrupting periodontal homeostasis in conjunction with oxidative stress. The association between reactive oxygen species (ROS) and osteolytic periodontitis have been suggested by recent studies. PTEN-induced kinase 1 (PINK1), a mitochondrial serine/threonine kinase, is an essential protein for mitochondrial quality control as it protects cells from oxidative stress by promoting degradation of damaged mitochondria through mitophagy. However, the pathophysiological roles of PINK1 in osteoclast-mediated bone loss have not been explored. Here we aimed to determine whether PINK1 plays a role in the regulation of osteoclastogenesis and alveolar bone resorption associated with periodontitis. C57BL/6 wild type (WT) and Pink1 knockout (KO) mice were subjected to ligature-induced periodontitis (LIP), and alveolar bones were evaluated by µCT-analysis and tartrate-resistant acid phosphatase (TRAP) staining. The µCT-analysis showed that bone volume fraction and travecular thickness were lower in Pink1 KO compared to WT mice. The number of TRAP-positive osteoclasts was markedly increased in the periodontal tissues of Pink1 KO mice with LIP. The genetic silencing or deletion of Pink1 promoted excessive osteoclast differentiation and bone resorption in vitro, as respectively indicated by TRAP staining and resorption pits on dentin slices. PINK1 deficiency led to mitochondrial instabilities as indicated by confocal microscopy of mitochondrial ROS, mitochondrial oxygen consumption rate (OCR) analysis, and transmission electron microscopy (TEM). Consequently, a significant increase in Ca2+-nuclear factor of activated T cells 1 (NFATc1) signaling was also found. On the other hand, restoration of mitophagy and autophagy by spermidine (SPD) treatment and the resolution of oxidative stress by N-acetyl-l-cysteine (NAC) treatment protected PINK1 deficiency-induced excessive generation of osteoclasts. Taken together, our findings demonstrate that PINK1 is essential for maintaining mitochondrial homeostasis during osteoclast differentiation. Therefore, targeting PINK1 may provide a novel therapeutic strategy for severe periodontitis with fulminant osteolysis.

Developmental roles of glomerular epithelial protein-1 in mice molar morphogenesis.

Glomerular epithelial protein-1 (Glepp1), a R3 subtype family of receptor-type protein tyrosine phosphatases, plays important role in the activation of Src family kinases and regulates cellular processes such as cell proliferation, differentiation, and apoptosis. In this study, we firstly examined the functional evaluation of Glepp1 in tooth development and morphogenesis. The precise expression level and developmental function of Glepp1 were examined by RT-qPCR, in situ hybridization, and loss and gain of functional study using a range of in vitro organ cultivation methods. Expression of Glepp1 was detected in the developing tooth germs in cap and bell stage of tooth development. Knocking down Glepp1 at E13 for 2 days showed the altered expression levels of tooth development-related signaling molecules, including Bmps, Dspp, Fgf4, Lef1, and Shh. Moreover, transient knock down of Glepp1 revealed alterations in cellular physiology, examined by the localization patterns of Ki67 and E-cadherin. Similarly, knocking down of Glepp1 showed disrupted enamel rod and interrod formation in 3-week renal transplanted teeth. In addition, due to attrition of odontoblastic layers, the expression signals of Dspp and the localization of NESTIN were almost not detected after knock down of Glepp1; however, their expressions were increased after Glepp1 overexpression. Thus, our results suggested that Glepp1 plays modulating roles during odontogenesis by regulating the expression levels of signaling molecules and cellular events to achieve the proper structural formation of hard tissue matrices in mice molar development.

Functional modulation of lysophosphatidic acid type 2 G-protein coupled receptor facilitates alveolar bone formation.

Lipid biosynthesis is recently studied its functions in a range of cellular physiology including differentiation and regeneration. However, it still remains to be elucidated in its precise function. To reveal this, we evaluated the roles of lysophosphatidic acid (LPA) signaling in alveolar bone formation using the LPA type 2 receptor (LPAR2) antagonist AMG-35 (Amgen Compound 35) using tooth loss without periodontal disease model which would be caused by trauma and usually requires a dental implant to restore masticatory function. In this study, in vitro cell culture experiments in osteoblasts and periodontal ligament fibroblasts revealed cell type-specific responses, with AMG-35 modulating osteogenic differentiation in osteoblasts in vitro. To confirm the in vivo results, we employed a mouse model of tooth loss without periodontal disease. Five to 10 days after tooth extraction, AMG-35 facilitated bone formation in the tooth root socket as measured by immunohistochemistry for differentiation markers KI67, Osteocalcin, Periostin, RUNX2, transforming growth factor beta 1 (TGF-ß1) and SMAD2/3. The increased expression and the localization of these proteins suggest that AMG-35 elicits osteoblast differentiation through TGF-ß1 and SMAD2/3 signaling. These results indicate that LPAR2/TGF-ß1/SMAD2/3 represents a new signaling pathway in alveolar bone formation and that local application of AMG-35 in traumatic tooth loss can be used to facilitate bone regeneration and healing for further clinical treatment.

Hip Fractures in Centenarians: Functional Outcomes, Mortality, and Risk Factors from a Multicenter Cohort Study.

Background: Increasing longevity has caused the very old population to become the fastest-growing segment. The number of centenarians (over 100 years old) is increasing rapidly. Fractures in the elderly lead to excessive medical costs and decreased quality of life with socioeconomic burdens. However, little research has thoroughly examined the functional outcomes and mortality of hip fractures in centenarians. Methods: This is a retrospective observational study. Sixty-eight centenarian hip fracture patients were admitted to the 10 institutions from February 2004 to December 2019. Fifty-six patients with 1-year follow-up were finally included. The following data were obtained: sex, age, body mass index, Charlson comorbidity index value on the operation day, Koval's classification for ambulatory ability, type of fracture, the time interval from trauma to surgery, American Society of Anesthesiologists grade, surgery-related complications, and duration of hospital stay. Postoperative Koval's classification (at 1 year after surgery) and information about death were also collected. Multivariate analysis was performed to analyze the risk factors affecting mortality 1 year after surgery. Results: Mortality rates were 26.8% at 6 months and 39.3% at 1 year. The 90-day mortality was 19.6%, and one of them (2.1%) died in the hospital. The 1-year mortality rates for the community ambulatory and non-community ambulatory groups were 29% and 52%, respectively. Only 9 (16.1%) were able to walk outdoors 1 year after surgery. The remaining 47 patients (83.9%) had to stay indoors after surgery. Multivariate analysis demonstrated that the pre-injury ambulatory level (adjusted hazard ratio, 2.884; p = 0.034) was associated with the risk of mortality. Conclusions: We report a 1-year mortality rate of 39.3% in centenarian patients with hip fractures. The risk factor for mortality was the pre-injury ambulatory status. This could be an important consideration in the planning of treatment for centenarian hip fracture patients.

Position Statement: Postmenopausal Osteoporosis Treatment Strategies in Korea.

Classifying patients with osteoporosis according to fracture risk and establishing adequate treatment strategies is crucial to effectively treat osteoporosis. The Korean Society for Bone and Mineral Research has issued a position statement regarding appropriate treatment strategies for postmenopausal osteoporosis. According to previous fragility fracture history, bone mineral density (BMD) test results, fracture risk assessment tool, and several clinical risk factors, fracture risk groups are classified into low, moderate, high, and very-high-risk groups. In high-risk groups, bisphosphonates (BPs) and denosumab are recommended as first-line therapies. Sequential BP treatment after denosumab discontinuation is required to prevent the rebound phenomenon. In the very high-risk group, anabolic drugs (teriparatide or romosozumab) are recommended as a first-line therapy; sequential therapy with antiresorptive agents is required to maintain BMD gain and reduce fracture risk. Fracture risk was reassessed annually, and the treatment plan was determined based on the results, according to the osteoporosis treatment algorithm for fracture risk.

Effectiveness and Usefulness of Bone Turnover Marker in Osteoporosis Patients: A Multicenter Study in Korea.

BACKGROUND: This study aimed to investigate real-world data of C-terminal telopeptide (CTX), propeptide of type I collagen (P1NP), and osteocalcin through present multicenter clinical study, and retrospectively analyze the usefulness of bone turnover markers (BTMs) in Koreans. METHODS: The study focused on pre- and post-menopausal patients diagnosed with osteoporosis and excluded patients without certain test results or with test intervals of over 1 year. The demographic data and 3 BTMs (CTX, P1NP, and osteocalcin) were collected. The patients were classified by demographic characteristics and the BTM concentrations were analyzed by the group. RESULTS: Among women with no history of fractures, the levels of P1NP (N=2,100) were 43.544±36.902, CTX (N=1,855) were 0.373 ±0.927, and osteocalcin (N=219) were 10.81 ±20.631. Among men with no history of fractures, the levels of P1NP (N=221) were 48.498±52.892, CTX (N=201) were 0.370±0.351, and osteocalcin (N=15) were 7.868 ±10.674. Treatment with teriparatide increased the P1NP levels after 3 months in both men and women, with a 50% increase observed in women. Similarly, treatment with denosumab decreased the CTX levels after 3 months in both men and women, with a reduction of 50% observed in women. CONCLUSIONS: The results of this study can contribute to the accurate assessment of bone replacement status in Koreans. We also provide the P1NP level in the Korean population for future comparative studies with other populations.

Comparison between osteonecrosis of the humeral and femoral heads - epidemiological analysis of the surgical trend using the nationwide claims database of the republic of Korea.

BACKGROUNDS: The humeral head is the second most common site of osteonecrosis, after the femoral head. However, compared to osteonecrosis of the femoral head (ONFH), epidemiological information on osteonecrosis of the humeral head (ONHH) is scarce. We hypothesised that different biomechanical properties of the shoulder from the hip joint might present different epidemiological characteristics of ONHH from those of the ONFH. To evaluate epidemiological differences, we compared trends in the surgical treatment of ONHH and ONFH using the nationwide medical claims database of the Republic of Korea (ROK). METHODS: We analysed epidemiological data from the Health Insurance Review and Assessment (HIRA) database of the ROK between 2008 and 2018. HIRA database contains almost all medical information in an anonymised form, including demographics, diagnoses, and types of surgical procedures, generated through healthcare practices in ROK. The annual incidence rates of ONHH and ONFH were calculated based on the total number of the general population. Demographics, annual incidence, and the proportion of post-traumatic osteonecrosis and surgical procedures were compared according to the anatomical site and the affected year. RESULTS: The total number of patients treated for ONHH and ONFH during the study period was 1,028 and 66,260, respectively. Although the incidence of ONHH increased, it is a relatively rare disease compared to ONFH. ONHH occurred more frequently in females, while ONFH occurred predominantly in male patients (p < 0.001). Surgical treatment for ONHH was most frequently performed in older patients (63.7%), whereas middle-aged patients had the largest proportion of ONFH (48.9%, p < 0.001). The proportion of post-traumatic osteonecrosis was significantly higher in the ONHH (5.1%) than in the ONFH (1.9%, p < 0.001). Arthroplasty was performed more frequently in the ONHH (96.0%) than in the ONFH (92.9%, p < 0.001). CONCLUSION: Despite the anatomical similarities between the hip and shoulder joints, the different biomechanical properties, such as weight-bearing functions, might cause epidemiological differences between ONHH and ONFH.

Effects of Thrombin-Based Hemostatic Agent in Total Knee Arthroplasty: Meta-Analysis.

The effectiveness of Floseal, a thrombin-based hemostatic matrix, in total knee arthroplasty (TKA) in minimizing blood loss and transfusion requirements remains a topic of debate. This meta-analysis aims to evaluate the up-to-date randomized controlled trials (RCTs) on the efficacy and safety of Floseal in TKA. A comprehensive search was conducted in electronic databases to identify relevant RCTs. The methodological quality of the included studies was assessed, and data extraction was performed. The pooled effect sizes were calculated using standardized mean difference (SMD) or odds ratios (OR) with 95% confidence intervals (CIs). Eight studies involving 904 patients were included in the meta-analysis. The use of a thrombin-based hemostatic agent significantly reduced hemoglobin decline (SMD = -0.49, 95% CI: -0.92 to -0.07) and the risk of allogenic transfusion (OR = 0.45, 95% CI: 0.25 to 0.81) but showed no significant difference in the volume of drainage or total blood loss. Funnel plots showed no evidence of publication bias. This meta-analysis provides robust evidence supporting the effectiveness of Floseal in reducing hemoglobin decline and transfusion in TKA. Further well-designed RCTs with longer follow-up periods are warranted to assess long-term efficacy and safety.

Periodontitis promotes bacterial extracellular vesicle-induced neuroinflammation in the brain and trigeminal ganglion.

Gram-negative bacteria derived extracellular vesicles (EVs), also known as outer membrane vesicles, have attracted significant attention due to their pathogenic roles in various inflammatory diseases. We recently demonstrated that EVs secreted by the periodontopathogen Aggregatibacter actinomycetemcomitans (Aa) can cross the blood-brain barrier (BBB) and that their extracellular RNA cargo can promote the secretion of proinflammatory cytokines, such as IL-6 and TNF-α, in the brain. To gain more insight into the relationship between periodontal disease (PD) and neuroinflammatory diseases, we investigated the effect of Aa EVs in a mouse model of ligature-induced PD. When EVs were administered through intragingival injection or EV-soaked gel, proinflammatory cytokines were strongly induced in the brains of PD mice. The use of TLR (Toll-like receptor)-reporter cell lines and MyD88 knockout mice confirmed that the increased release of cytokines was triggered by Aa EVs via TLR4 and TLR8 signaling pathways and their downstream MyD88 pathway. Furthermore, the injection of EVs through the epidermis and gingiva resulted in the direct retrograde transfer of Aa EVs from axon terminals to the cell bodies of trigeminal ganglion (TG) neurons and the subsequent activation of TG neurons. We also found that the Aa EVs changed the action potential of TG neurons. These findings suggest that EVs derived from periodontopathogens such as Aa might be involved in pathogenic pathways for neuroinflammatory diseases, neuropathic pain, and other systemic inflammatory symptoms as a comorbidity of periodontitis.

Position Statement: Atypical Femoral Fracture from the Korean Society for Bone and Mineral Research in 2023.

As the aging population increases, the number of patients with osteoporosis is gradually rising. Osteoporosis is a metabolic bone disease characterized by low bone mass and the microarchitectural deterioration of bone tissue, resulting in reduced bone strength and an increased risk of low-energy or fragility fractures. Thus, the use of anti-resorptive agents, such as bisphosphonates (BPs), to prevent osteoporotic fractures is growing annually. BPs are effective in reducing hip and other fractures. However, the longer a patient takes BPs, the higher the risk of an atypical femoral fracture (AFF). The exact mechanism by which long-term BP use affects the development of AFFs has not yet been clarified. However, several theories have been suggested to explain the pathogenesis of AFFs, such as suppressed bone remodeling, impaired bone healing, altered bone quality, and femoral morphology. The management of AFFs requires both medical and surgical approaches. BPs therapy should be discontinued immediately, and calcium and vitamin D levels should be evaluated and supplemented if insufficient. Teriparatide can be used for AFFs. Intramedullary nailing is the primary treatment for complete AFFs, and prophylactic femoral nailing is recommended if signs of an impending fracture are detected.

Prevention of Venous Thromboembolism in Patients Undergoing Hip Fracture Surgery: A Survey of the Korean Hip Society.

Purpose: The aim of this study was to assess the current status of venous thromboembolism (VTE) prevention in Korean patients with hip fractures. Materials and Methods: A survey using a questionnaire on the experiences and protocols of VTE prevention was conducted among 570 members of the Korean Hip Society. Results: A total of 97 surgeons responded, with a response rate of 17.0%. Of the 97 participants, 61.9% answered that they had encountered one or more cases of symptomatic VTE in the past year. Mechanical prophylaxis was applied most often (30.9%) until the point of ambulation in standard-risk patients and most often (34.0%) extended until discharge in high-risk patients. Chemical prophylaxis was most often prescribed for a particular period of time rather than for recovery of walking ability (24.7% in standard-risk patients and 26.8% in high-risk patients). Dual prophylaxis was administered in the standard-risk group by 58.8% of the participants and in the high-risk group by 83.5%. Among the participants, 73.2% answered that they had been attentive to wound complications during chemical prophylaxis. More than half of the participants (59.8%) reported that they did not perform routine screening for VTE after surgery. Conclusion: The results of our survey provided information regarding the current status of VTE prevention for patients undergoing surgery for treatment of hip fractures in Korea as well as a baseline for establishment of educational programs and guidelines in the future.

Treatment of Femoral Neck Fractures in the Elderly: A Survey of the Korean Hip Society Surgeons.

Purpose: This study examined the methods for treatment of femoral neck fracture (FNF) preferred by members of the Korean Hip Society (KHS) and identified factors that influence decisions regarding the surgical intervention of choice. Materials and Methods: A total of 97 members of the KHS responded to the 16-question survey which included questions about the mean number of surgeries performed each month for treatment of femoral neck fractures, the cut-off age for deciding between internal fixation and arthroplasty, the implant used most often, usage of cement, and factors influencing each decision. Results: The mean cut-off age used when deciding between internal fixation and arthroplasty was 64 years old. Hemiarthroplasty (HA) (70%) was the most preferred option for treatment of displaced FNFs in cases where arthroplasty was indicated (total hip arthroplasty [THA] 19% and dual mobility THA 11%). The main reasons for selection of arthroplasty over reduction with internal fixation were age and pre-fracture ambulatory status. Pre-trauma ambulatory status and/or sports activity were the main factors in selection of HA over THA. Cement was used by 33% of responders. Poor bone quality and a broad femoral canal were factors that influenced the usage of cement. Conclusion: Management of FNFs in the elderly is a major health problem worldwide; thus, remaining alert to current trends in treatment is essential for surgeons. The mean cut-off age used in deciding between internal fixation and arthroplasty was 64 years old. HA is the preferred method for treatment of displaced FNFs for members of the KHS.

Updating Osteonecrosis of the Femoral Head.

Osteonecrosis of the femoral head (ONFH), a condition characterized by the presence of a necrotic bone lesion in the femoral head, is caused by a disruption in the blood supply. Its occurrence is more common in young and middle-aged adults and it is the main reason for performance of total hip arthroplasty in this age group. Its incidence is increasing along with increased use of glucocorticoids for management of adjuvant therapy for treatment of leukemia as well as organ transplantation and other myelogenous diseases. Current information on etiology and pathogenesis, as well as natural history, stage system, and treatments is provided in this review. A description of the Association Research Circulation Osseous (ARCO) criteria for classification of glucocorticoids- and alcohol-associated ONFH, 2019 ARCO staging system, and 2021 ARCO classification using computed tomography for the early stages of ONFH is also provided.

Effects of Bazedoxifene/Vitamin D Combination Therapy on Serum Vitamin D Levels and Bone Turnover Markers in Postmenopausal Women with Osteopenia: A Randomized Controlled Trial.

BACKGROUND: This study aimed to evaluate the effectiveness of bazedoxifene/vitamin D combination therapy in preventing osteoporosis in postmenopausal women with osteopenia. METHODS: This was an open-label, multicenter randomized-controlled, phase 4 clinical trial. Women between ages of 55 and 70 years in 9 medical tertiary centers in Korea were enrolled and assigned into 2 groups: an experiment group and a control group. The experimental group received bazedoxifene 20 mg/vitamin D 800 IU tablets for 6 months, and the control group received calcium 100 mg/vitamin D 1,000 IU tablets for 6 months. RESULTS: A total of 142 patients (70 in the experimental group and 72 in the control group) were included. The least-square mean±standard error of change in propeptide of type I collagen after 3 months was -6.87±2.56% in the experimental group and 1.22±2.54% in the control group. After 6 months, it was -21.07±2.75% in the experimental group and 1.26±2.71% in the control group. The difference between the 2 groups was -22.33% (p<0.01). The change of C-terminal telopeptide was -12.55±4.05% in the experimental group and 11.02±4.03% in the control group after 3 months. It was -22.0±3.95% and 10.20±3.89, respectively, after 6 months. The difference between the 2 groups was -32.21% (p<0.01) after 6 months. There was no significant difference in adverse events between the 2 groups. CONCLUSIONS: The osteoporosis preventive effect and safety of administering bazedoxifene/vitamin D combination pill were confirmed in postmenopausal women who needed osteoporosis prevention.

Association of Androgen Deprivation Therapy with Osteoporotic Fracture in Patients with Prostate Cancer with Low Tumor Burden Using a Retrospective Population-Based Propensity-Score-Matched Cohort.

This study evaluated the effect of androgen deprivation therapy (ADT) on osteoporotic fractures (OF) and its prognostic effect on overall survival in patients with localized or regional prostate cancer (PC) using the Korean National Insurance Dataset. A total of 8883 pairs of 1:1 propensity-score-matched patients with localized or regional PC were retrospectively enrolled between 2007 and 2016. All patients underwent at least 1 year of follow-up to evaluate therapeutic outcomes. Multivariate analysis was performed to determine the prognostic effect of ADT on OF. During a mean follow-up of 47.7 months, 977 (3.43%) patients developed OF, and the incidences of hip, spine, and wrist fractures were significantly different between ADT and non-ADT groups (p < 0.05). The ADT group had a significantly higher incidence of OF (hazard ratio 2.055, 95% confidence interval 1.747-2.417) than the non-ADT group (p < 0.05), and the incidence of spine/hip/wrist OF was significantly higher in the ADT group regardless of the PC stage (p < 0.05). Multivariate analysis failed to show any significant difference in overall survival between the two groups (p > 0.05). ADT resulted in a significantly higher incidence of OF among patients with localized and regional PC, but the overall survival did not differ between ADT and non-ADT groups.

Incidence and Risk Factors of Short Axial Length of the Proximal Femur: A Caution in the Use of Femoral Neck System in Patients with Garden Type I/II Femoral Neck Fractures.

Background: In 2018, Femoral Neck System (FNS), a dedicated fixator for femoral neck fractures, was introduced. This device has been in increasing use because it provides excellent rotational and angular stability. However, the shortest bolt of FNS is 75 mm long. Thus, it is not usable when the axial length of the proximal femur (ALPF), the distance between the innominate tubercle and the surface of the femoral head, is less than 80 mm. In this study, we investigated the incidence and associated factors of small ALPF (< 80 mm) in femoral neck fracture patients. Methods: We measured the ALPF on preoperative computed tomography (CT) scans of 261 patients (166 women and 55 men), who were operated due to nondisplaced or impacted femoral neck fractures. The ALPF was measured on reconstructed oblique coronal images along the femoral neck. We evaluated the distribution of ALPF, calculated the incidence of small ALPF (< 80 mm), and correlated it with patient's height, weight, body mass index, age, bone mineral density (T-score), and caput-column-diaphysis angle. Results: The ALPF ranged from 67.4 mm to 107.1 mm (mean, 88.4 mm; standard deviation, 7.2 mm). In 19 patients (8.6%, 19 / 221), the length was < 80 mm. The ALPF was strongly correlated with height (correlation coefficient = 0.707, R2 = 0.500, p < 0.001) and moderately correlated with weight (correlation coefficient = 0.551, R2 = 0.304, p < 0.001). The T-score was moderately correlated with the ALPF (correlation coefficient = 0.433, R2 = 0.187, p < 0.001). The age was moderately correlated with the ALPF (correlation coefficient =-0.353, R2 = 0.123, p < 0.001). Conclusions: A considerable percentage of femoral neck fracture patients (8.6%) had small proximal femurs (ALPF < 80 mm), which cannot be operated with FNS. We recommend measuring the ALPF using reconstructed oblique coronal CT images or scaled hip radiographs: en face view of the femoral neck prior to surgery in patients with short stature and/or low body weight. If the ALPF is < 80 mm, the surgeon should prepare other fixation devices.