Developing an exercise intervention to minimise hip bone mineral density loss following traumatic lower limb amputation: a Delphi study.

OBJECTIVE: To elicit expert opinion and gain consensus on specific exercise intervention parameters to minimise hip bone mineral density (BMD) loss following traumatic lower limb amputation. METHODS: In three Delphi rounds, statements were presented to a panel of 13 experts from six countries. Experts were identified through publications or clinical expertise. Round 1 involved participants rating their agreement with 22 exercise prescription statements regarding BMD loss post amputation using a 5-point Likert scale. Agreement was deemed as 3-4 on the scale (agree/strongly agree). Statements of <50% agreement were excluded. Round 2 repeated remaining statements alongside round 1 feedback. Round 3 allowed reflection on round 2 responses considering group findings and the chance to change or maintain the resp onse. Round 3 statements reaching ≥70% agreement were defined as consensus. RESULTS: All 13 experts completed rounds 1, 2 and 3 (100% completion). Round 1 excluded 12 statements and added 1 statement (11 statements for rounds 2-3). Round 3 reached consensus on nine statements to guide future exercise interventions. Experts agreed that exercise interventions should be performed at least 2 days per week for a minimum of 6 months, including at least three different resistance exercises at an intensity of 8-12 repetitions. Interventions should include weight-bearing and multiplanar exercises, involve high-impact activities and be supervised initially. CONCLUSION: This expert Delphi process achieved consensus on nine items related to exercise prescription to minimise hip BMD loss following traumatic lower limb amputation. These recommendations should be tested in future interventional trials.

Physical fitness components are bone mineral density predictors in adulthood: cross-sectional study.

BACKGROUND: Health-related physical fitness (HRPF) attributes are considered important markers beneficial to various health outcomes. However, the literature is divergent regarding HRPF and bone health in adulthood, especially due to the end of the second and beginning of the third decades of life when the peak bone mass period occurs. OBJECTIVE: To analyze which HRPF variables are areal bone mineral density (aBMD) predictors in adult males and females. METHODS: This study evaluated 137 healthy young adults aged 18-25 years (50% males). Dual-energy X-ray absorptiometry (DXA) was used to estimate fat mass and lean mass and aBMD, hand grip strength test, sit-ups test, flexibility test, lower limb muscle strength and 20-meter run were used to evaluate physical fitness. Multiple linear regression using the backward method was used to analyze bone mineral density predictors by sex. RESULTS: HRPF indicators showed correlations from R = 0.28 in the right femoral neck aBMD to R = 0.61 in the upper limbs aBMD in males; in females, correlations from R = 0.27 in total body aBMD to R = 0.68 in the lower limbs aBMD were found. In males, body mass and HRPF indicators were aBMD predictors with HRPF indicators explaining variance from R²=0.214 in the lumbar spine to R²=0.497 in the upper limbs, and in females, with the exception of the lumbar spine, variance from R²=0.237 in the right femoral neck aBMD to R²=0.442 in the lower limbs aBMD was found. CONCLUSION: Health-related physical fitness components were able to predict aBMD in different anatomical regions in young adults, especially muscle strength and cardiorespiratory fitness indicators for males, while only lean mass and fat mass for females.

Diagnostic Accuracy of Dual-Energy CT-Derived Metrics for the Prediction of Osteoporosis-Associated Fractures.

RATIONALE AND OBJECTIVES: This study aimed to compare the diagnostic value of dual-energy CT (DECT)-based volumetric material decomposition with that of Hounsfield units (HU)-based values and cortical thickness ratio for predicting the 2-year risk of osteoporosis-associated fractures. METHODS: The L1 vertebrae of 111 patients (55 men, 56 women; median age, 62 years) who underwent DECT between 01/2015 and 12/2018 were retrospectively analyzed. For phantomless bone mineral density (BMD) assessment, a specialized DECT postprocessing software employing material decomposition was utilized. The digital records of all patients were monitored for two years after the DECT scans to track the incidence of osteoporotic fractures. Diagnostic accuracy parameters were calculated for all metrics using receiver-operating characteristic (ROC) and precision-recall (PR) curves. Logistic regression models were used to determine associations of various predictive metrics with the occurrence of osteoporotic fractures. RESULTS: Patients who sustained one or more osteoporosis-associated fractures in a 2-year interval were significantly older (median age 74.5 years [IQR 57-83 years]) compared those without such fractures (median age 50.5 years [IQR 38.5-69.5 years]). According to logistic regression models, DECT-derived BMD was the sole predictive parameter significantly associated with osteoporotic fracture occurrence across all age groups. ROC and PR curve analyses confirmed the highest diagnostic accuracy for DECT-based BMD, with an area under the curve (AUC) of 0.95 [95% CI: 0.89-0.98] for the ROC curve and an AUC of 0.96 [95% CI: 0.85-0.99] for the PR curve. CONCLUSION: The diagnostic performance of DECT-based BMD in predicting the 2-year risk of osteoporotic fractures is greater than that of HU-based metrics and the cortical thickness ratio. DECT-based BMD values are highly valuable in identifying patients at risk for osteoporotic fractures.

Influence of Crown Height and Width on Marginal Bone Loss and Long-Term Stability of Dental Implants: A Systematic Review.

Still, a major focus of research in implantology is how crown height and width affect marginal bone loss (MBL) and the long-term durability of dental implants. Maximizing the success of implants and lowering problems depends on an awareness of these elements. Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, this systematic review searched pertinent studies across several databases using keywords unique to databases. Studies on MBL and long-term implant stability evaluated in the review included those on crown height and width, horizontal and vertical cantilevers, and prosthesis dimensions. In the chosen studies, we found that both implant success and crestal bone loss were greatly influenced by crown height and width. Particularly in the posterior sections, horizontal cantilevers were connected to both increasing MBL and mechanical problems. Vertical cantilevers also affected MBL; however, their impacts were more obvious in circumstances with greater crown heights. Greater prosthesis widths, especially in the mandibular molar area, were linked to higher MBL. Bone density and insertion torque (IT) were the main determinants of MBL, more than the primary implant stability quotient. Early MBL was influenced by abutment height, mucosal thickness, and implant insertion depth; bone levels stabilized six months later. Short implants allow single crowns to be supported, but in some cases, a higher failure rate was seen. The success and stability of dental implants were found to be mostly dependent on crown height, width, and cantilever design. MBL and long-term stability are greatly influenced by horizontal and vertical cantilevers, which calls for careful design and planning. With specific care for bone density, IT, and early MBL stabilization, both short and standard implants can produce equivalent results. These results highlight the need for customized treatment plans to maximize implant success and lifetime.

Diagnostic accuracy of artificial intelligence models in detecting osteoporosis using dental images: a systematic review and meta-analysis.

The current study aimed to systematically review the literature on the accuracy of artificial intelligence (AI) models for osteoporosis (OP) diagnosis using dental images. A thorough literature search was executed in October 2022 and updated in November 2023 across multiple databases, including PubMed, Scopus, Web of Science, and Google Scholar. The research targeted studies using AI models for OP diagnosis from dental radiographs. The main outcomes were the sensitivity and specificity of AI models regarding OP diagnosis. The "meta" package from the R Foundation was selected for statistical analysis. A random-effects model, along with 95% confidence intervals, was utilized to estimate pooled values. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was employed for risk of bias and applicability assessment. Among 640 records, 22 studies were included in the qualitative analysis and 12 in the meta-analysis. The overall sensitivity for AI-assisted OP diagnosis was 0.85 (95% CI, 0.70-0.93), while the pooled specificity equaled 0.95 (95% CI, 0.91-0.97). Conventional algorithms led to a pooled sensitivity of 0.82 (95% CI, 0.57-0.94) and a pooled specificity of 0.96 (95% CI, 0.93-0.97). Deep convolutional neural networks exhibited a pooled sensitivity of 0.87 (95% CI, 0.68-0.95) and a pooled specificity of 0.92 (95% CI, 0.83-0.96). This systematic review corroborates the accuracy of AI in OP diagnosis using dental images. Future research should expand sample sizes in test and training datasets and standardize imaging techniques to establish the reliability of AI-assisted methods in OP diagnosis through dental images.

Significant decrease of osteoporosis and osteoporotic fractures in rheumatoid arthritis within a period of 24 years: experiences of a single centre.

OBJECTIVES: Rheumatoid arthritis (RA) is associated with an increased risk for osteoporosis and osteoporotic fractures. Since the treatment of RA has improved significantly in recent years, we can expect RA-associated osteoporosis to decrease with good disease control. Therefore, we conducted a retrospective study to investigate whether the frequency of osteoporosis and osteoporotic fractures has changed during 24 years in RA. METHODS: We analysed the data of 1.086 RA patients from the time of the first osteological assessment with bone mineral density (BMD) measurement and collection of osteologically important data during the years 1996 and 2019 at our clinic. According to the treatment period, the patients were divided into cohort 1 (investigation between 1996 and 2004; n=539) and cohort 2 (investigation between 2005 and 2019; n=547). The data of the two cohorts were compared, and predictors of BMD were analysed by linear regression analysis. RESULTS: Prevalence of osteoporosis (28.3% vs 48.4%; p<0.001) as well as osteoporotic peripheral fractures (11.5% vs 21%; p<0.001) and vertebral fractures (6.6% vs 10.9%; p=0.011) were significantly lower and treatment with biologicals (19.7% vs 5.0%; p<0.001) significantly more common and glucocorticoid use was significantly less common (p=0.005) in cohort 2. In RA patients with a disease duration of more than 2 years, BMD was significantly higher under treatment with biologicals (p<0.001) despite increased cumulative glucocorticoid dosages (p<0.001). CONCLUSION: Our study showed a significant decline in osteoporosis and osteoporotic fractures in RA for 24 years. This positive effect is associated with the more frequent use of biologicals in the years between 2005 and 2019.

A cost-free approach to evaluating vertebral body bone density and height loss in lung transplant recipients using routine chest CT.

BACKGROUND: To assess changes in bone density and vertebral body height of patients undergoing lung transplant surgery using computed tomography (CT). METHODS: This institutional review board (IRB) approved retrospective observational study enrolled patients with a history of lung transplant who had at least two chest CT scans. Vertebral body bone density (superior, middle, and inferior sections) and height (anterior, middle, and posterior sections) were measured at T1-T12 at baseline and follow up CT scans. Changes in the mean bone density, mean vertebral height, vertebral compression ratio (VBCR), percentage of anterior height compression (PAHC), and percentage of middle height compression (PMHC) were calculated and analyzed. RESULTS: A total of 93 participants with mean age of 58 ± 12.3 years were enrolled. The most common underlying disease that led to lung transplants was interstitial lung diseases (57 %). The inter-scan interval was 34.06 ± 24.8 months. There were significant changes (p-value < 0.05) in bone density at all levels from T3 to T12, with the greatest decline at the T10 level from 163.06 HU to 141.84 HU (p-value < 0.05). The average VBCR decreased from 96.91 to 96.15 (p-value < 0.05). CONCLUSION: Routine chest CT scans demonstrate a gradual decrease in vertebral body bone density over time in lung transplant recipients, along with evident anatomic changes such as vertebral body bone compression. This study shows that utilizing routine chest CT for lung transplant recipients can be regarded as a cost-free tool for assessing the vertebral body bone changes in these patients and potentially aiding in the prevention of complications related to osteoporosis.

Reproducibility of CT-based opportunistic vertebral volumetric bone mineral density measurements from an automated segmentation framework.

BACKGROUND: To investigate the reproducibility of automated volumetric bone mineral density (vBMD) measurements from routine thoracoabdominal computed tomography (CT) assessed with segmentations by a convolutional neural network and automated correction of contrast phases, on diverse scanners, with scanner-specific asynchronous or scanner-agnostic calibrations. METHODS: We obtained 679 observations from 278 CT scans in 121 patients (77 males, 63.6%) studied from 04/2019 to 06/2020. Observations consisted of two vBMD measurements from Δdifferent reconstruction kernels (n = 169), Δcontrast phases (n = 133), scan Δsessions (n = 123), Δscanners (n = 63), or Δall of the aforementioned (n = 20), and observations lacking scanner-specific calibration (n = 171). Precision was assessed using root-mean-square error (RMSE) and root-mean-square coefficient of variation (RMSCV). Cross-measurement agreement was assessed using Bland-Altman plots; outliers within 95% confidence interval of the limits of agreement were reviewed. RESULTS: Repeated measurements from Δdifferent reconstruction kernels were highly precise (RMSE 3.0 mg/cm3; RMSCV 1.3%), even for consecutive scans with different Δcontrast phases (RMSCV 2.9%). Measurements from different Δscan sessions or Δscanners showed decreased precision (RMSCV 4.7% and 4.9%, respectively). Plot-review identified 12 outliers from different scan Δsessions, with signs of hydropic decompensation. Observations with Δall differences showed decreased precision compared to those lacking scanner-specific calibration (RMSCV 5.9 and 3.7, respectively). CONCLUSION: Automatic vBMD assessment from routine CT is precise across varying setups, when calibrated appropriately. Low precision was found in patients with signs of new or worsening hydropic decompensation, what should be considered an exclusion criterion for both opportunistic and dedicated quantitative CT. RELEVANCE STATEMENT: Automated CT-based vBMD measurements are precise in various scenarios, including cross-session and cross-scanner settings, and may therefore facilitate opportunistic screening for osteoporosis and surveillance of BMD in patients undergoing routine clinical CT scans. KEY POINTS: Artificial intelligence-based tools facilitate BMD measurements in routine clinical CT datasets. Automated BMD measurements are highly reproducible in various settings. Reliable, automated opportunistic osteoporosis diagnostics allow for large-scale application.

Exploring bone density analysis on routine CT scans as a tool for opportunistic osteoporosis screening.

The primary aim of this study was to evaluate computed tomography (CT)-based bone density analysis at the level of thoracic vertebra 12 (Th12) as a screening method for decreased bone density in patients admitted to the intensive care unit (ICU). Interobserver variability was analyzed. Secondary aims were to assess the prevalence of CT-based low bone density upon ICU admission in a cohort of COVID-19 patients and to assess the potential effect of long-term ICU stay on bone density in these patients. Retrospective single-center cohort study. ICU of the Leiden University Medical Center (LUMC), the Netherlands. Patients admitted to the ICU of the LUMC between March 1st, 2020 and February 1st, 2022 with a diagnosis of COVID-19, and a length of ICU stay of ≥ 21 days. In the included patients both baseline chest CT scans (obtained upon ICU admission) and follow-up chest CT scans (obtained ≥ 21 days after ICU admission) were available for analysis. A total of 118 CT scans in 38 patients were analyzed. There was a good interobserver variability, with an overall mean absolute difference (between measurements of three observers) of 9.7 Hounsfield Units (HU) and an intraclass correlation coefficient (ICC) of 0.93 (95% CI 0.88-0.96). The effect of intravenous contrast administration on bone density measurements was small (+ 7.5 HU (95% CI 3.4-11.5 HU)) higher in contrast enhanced CT images compared to non contrast enhanced CT images). Thirty-seven percent of patients had a bone density < 140 HU, suggestive of osteoporosis. No significant difference was found between bone density upon ICU admission and bone density at follow-up (≥ 21 days after ICU admission). Vertebral CT-based bone density analysis using routine CT scans is an easily applicable method to identify ICU patients with decreased bone density, which could enable enrollment in osteoporosis prevention programs. A high prevalence of low bone density was found in our cohort of ICU patients. There were no changes observed in bone density between baseline and follow-up measurements.

Effect of Photobiomodulation on Crestal Bone Density Around Dental Implants: A Case Report.

Dental implants are becoming a necessary component of the dental profession. The first bone resorption at the implant surface has an impact on implant success. Bone alterations surrounding the implant are a significant factor in determining the implant's effectiveness. Reducing the loss of peri-implant crestal bone has been a constant goal. In dental implantology, several procedures are carried out to improve implant stability and the healing of the bone. The ability of photobiomodulation techniques or low-level laser therapy (LLLT) to speed up osseointegration by inducing cellular metabolism and stimulating tissue healing has made them popular. This case study details the implant loading in a patient treated with photobiomodulation to achieve implant stability and who has compromised bone type or D4.

Botulinum toxin type A injection into the masticatory muscles and its effects on mandibular bone resorption and density. A systematic review.

OBJECTIVE: This systematic review aims to summarize and synthesize the evidence that investigates the secondary effects of the application of botulinum toxin (BT) into the masticatory muscles and its effects on bone density. MATERIALS AND METHODS: Database searches were conducted until March 19th, 2024. The quality of the studies was assessed by the Cochrane tool risk of bias for the randomized controlled trials and the ROBINS-I tool for non-randomized studies. The Cochrane Grading of Recommendations Assessment Development and Evaluation (GRADE) was used to evaluate the confidence in the overall evidence. RESULTS: Five studies looking at the effects of botulinum toxin on bone density and resorption when applied to masticatory muscles were found. No significant changes were observed in most of the studies when looking at the effects of botulinum toxin on mandibular condyle volume, density, mandibular angle thickness, and coronoid process volume. The only finding that was statistically and clinically relevant was the difference between patients who received a double application of BT when compared with patients who received a single application (SMD: -0.99 [95%CI: -1.94,-0.05]) on the volume of the mandibular angle. CONCLUSIONS: There is no clear pattern on whether the application of botulinum toxin is associated with bone resorption or not. Although some studies show statistical significance of the findings, the magnitude of the changes in bone density and their clinical significance are not completely clear. CLINICAL RELEVANCE: To understand the effectiveness of the use of botulinum toxin into the masticatory muscles and its possible secondary adverse effects on the density of the mandible.

The reduced cortical bone density in vertebral bodies: risk for osteoporotic fractures? Insights from CT analysis.

BACKGROUND: There is a corresponding increase in the prevalence of osteoporosis and related fractures with the aging population on the rise. Furthermore, osteoporotic vertebral compression fractures (OVCF) may contribute to higher patient mortality rates. It is essential to conduct research on risk factors for OVCF and provide a theoretical basis for preventing such fractures. METHODS: We retrospectively recruited patients who had spine CT for OVCF or back pain. Demographic and CT data were collected. Quantitative computed tomography (QCT) software analyzed the CT data, using subcutaneous fat and paraspinal muscles as reference standards for BMD processing. BMD of cortical and cancellous bones in each patient's vertebral body was determined. RESULTS: In this study, 144 patients were divided into non-OVCF (96) and OVCF (48) groups. Non-OVCF patients had higher cortical BMD of 382.5 ± 52.4 to 444.6 ± 70.1 mg/cm3, with T12 having the lowest BMD (p < 0.001, T12 vs. L2). Cancellous BMD ranged from 128.5 ± 58.4 to 140.9 ± 58.9 mg/cm3, with L3 having the lowest BMD. OVCF patients had lower cortical BMD of 365.0 ± 78.9 to 429.3 ± 156.7 mg/cm3, with a further decrease in T12 BMD. Cancellous BMD ranged from 71.68 ± 52.07 to 123.9 ± 126.2 mg/cm3, with L3 still having the lowest BMD. Fractured vertebrae in OVCF patients (T12, L1, and L2) had lower cortical bone density compared to their corresponding vertebrae without fractures (p < 0.05). CONCLUSIONS: T12 had the lowest cortical BMD and L3 had the lowest cancellous BMD in OVCF patients, with T12 also having the highest incidence of osteoporotic fractures. These findings suggest that reduction in cortical BMD has a greater impact on OVCF than reduction in cancellous BMD, along with biomechanical factors.

Machine Learning Models Can Define Clinically Relevant Bone Density Subgroups based on Patient Specific Calibrated CT Scans in Patients Undergoing Reverse Shoulder Arthroplasty.

BACKGROUND: Reduced bone density is recognized as a predictor for potential complications in reverse shoulder arthroplasty (RSA). While humeral and glenoid planning based on preoperative computed tomography (CT) scans assist in implant selection and position, reproducible methods for quantifying the patients' bone density are currently not available. The purpose of this study was to perform bone density analyses including patient specific calibration in an RSA cohort based on preoperative CT imaging. It was hypothesized that preoperative CT bone density measures would provide objective quantification of the patients' humeral bone quality. METHODS: This study consisted of three parts, (1) analysis of a patient-specific calibration method in cadaveric CT scans, (2) retrospective application in a clinical RSA cohort, and (3) clustering and classification with machine learning models. Forty cadaveric shoulders were scanned in a clinical CT and compared regarding calibration with density phantoms, air muscle, and fat (patient-specific) or standard Hounsfield unit. Post-scan patient-specific calibration was used to improve the extraction of three-dimensional regions of interest for retrospective bone density analysis in a clinical RSA cohort (n=345). Machine learning models were used to improve the clustering (Hierarchical Ward) and classification (Support Vector Machine (SVM)) of low bone densities in the respective patients. RESULTS: The patient-specific calibration method demonstrated improved accuracy with excellent intraclass correlation coefficients (ICC) for cylindrical cancellous bone densities (ICC>0.75). Clustering partitioned the training data set into a high-density subgroup consisting of 96 patients and a low-density subgroup consisting of 146 patients, showing significant differences between these groups. The SVM showed optimized prediction accuracy of low and high bone densities compared to conventional statistics in the training (accuracy=91.2%; AUC=0.967) and testing (accuracy=90.5 %; AUC=0.958) data set. CONCLUSION: Preoperative CT scans can be used to quantify the proximal humeral bone quality in patients undergoing RSA. The use of machine learning models and patient-specific calibration on bone mineral density demonstrated that multiple 3D bone density scores improved the accuracy of objective preoperative bone quality assessment. The trained model could provide preoperative information to surgeons treating patients with potentially poor bone quality.

Fragility Fractures and Cortisol Secretion in Patients With Nonfunctioning Adrenal Incidentalomas.

Context: The risk of vertebral fractures (VFx) in patients with nonfunctioning adrenal incidentalomas (NFAI) is unknown. Objective: This work aimed to assess in NFAI patients the prevalence and incidence of VFx and a hormonal marker to identify patients at risk. Methods: A retrospective, cross-sectional, and longitudinal study of outpatients was conducted. A total of 306 NFAI patients (cross-sectional arm) and 213 controls were evaluated for VFx prevalence; 85 NFAI patients (longitudinal arm, follow-up 30.3 ± 17.5 months) were evaluated for VFx incidence. Main outcome measures included serum cortisol after 1 mg-dexamethasone test (F-1mgDST), lumbar spinal (LS), and femoral neck (FN) bone mineral density (BMD) and VFx presence, by radiograph of the spine. Results: Cross-sectional arm: prevalent VFx associated with F-1mgDST with a cutoff of 1.2 µg/dL (33 nmol/L, area under the curve 0.620 ± 0.39; P = .002). Compared with controls and NFAI patients with F-1mgDST less than 1.2 µg/dL (group A), NFAI patients with F-1mgDST greater than or equal to 1.2 µg/dL (group B) showed a higher VFx prevalence (10.8%, 12.6%, and 29.5%, respectively; P < .001 all comparisons), which was associated with F-1mgDST greater than or equal to 1.2 µg/dL (odds ratio 3.02; 95% CI, 1.63-5.58; P < .001) accounting to confounders. Longitudinal arm: the VFx incidence was higher in group B than in group A (19.3% vs 3.6%; P = .05). In group B, all incident VFx occurred in patients without low BMD. The F-1mgDST cutoff for predicting an incident VFx was 1.2 µg/dL, although statistical significance was not reached after adjustment for confounders (P = .061). Conclusion: In NFAI patients, F-1mgDST levels greater than or equal to 1.2 µg/L (33 nmol/L) are associated with prevalent VFx and may identify patients at risk of incident VFx.

Effectiveness of using implant fixture as a ridge expander.

OBJECTIVES: Adequate bone thickness around dental implants is vital for their stability and to reduce resorption. This study evaluated the ability of implant fixtures to serve as ridge expanders by measuring width changes pre- and post-implantation. MATERIALS AND METHODS: Measurements including initial alveolar bone width, post-osteotomy width, post-expansion width, and buccal bone thickness were recorded for patients undergoing implant placement. Bone quality was assessed using established criteria. RESULTS: Of the 102 subjects (52% male, 48% female), significant ridge width increases at 0 mm and 2 mm levels were noted (p < 0.05). Larger implant diameters resulted in greater ridge expansion. Absence of prior augmentation was linked to higher bone quality (B = -1.684, p = 0.001), explaining 15% of bone quality variance. Ridge expansion effects also correlated with the site, implant diameter, and design. CONCLUSIONS: Dental implant fixtures can effectively expand the ridge, with expansion influenced by implant diameter, anatomical location, prior augmentation, and implant design. These factors must be considered for tailored treatment planning in implant dentistry. CLINICAL RELEVANCE: This study's clinical relevance lies in its exploration of the potential benefits of dental implant fixtures can effectively to expand the ridge taking into consideration implant diameter, anatomical location, prior augmentation, and implant design.

Association of dorsal malunion in distal radius fractures with wrist osteoarthritis: Alterations of bone density and stress-distribution patterns in relation to deformation angles.

OBJECTIVE: Distal radius fractures (DRFs) with dorsal malunion increase the risk of osteoarthritis (OA), although the cause of post-DRF OA is yet to be elucidated. To clarify the abnormal effects of a post-DRF dorsal radius deformity, we evaluated the bone density (BD) and stress-distribution patterns of the articular surface in dorsally malunited DRFs. DESIGN: In 36 cases of dorsally malunited DRFs following extra-articular fractures, we generated three-dimensional computerized models of the malunited distal radius from computed tomography data and extracted the subchondral bones of the radiocarpal joint (RCJ) and distal radioulnar joint (DRUJ). Both BD and stress distribution in the subchondral bones were quantitatively evaluated by comparing the affected and normal sides. Correlations of alterations in high-BD distribution and deformation angles were analyzed. RESULTS: The center of high-BD distribution from the center of the RCJ in the volar(-)-dorsal(+) direction was dorsal (0.56 ± 0.72 mm) on the affected side compared with the normal side (-0.15 ± 0.63 mm) [95% CI: 0.43, 1.00, P < 0.0001]. The maximum stress distribution was also dorsal on the affected side (2.34 ± 3.52 mm) compared with the normal side (-2.49 ± 1.62 mm) [95% CI: 0.89, 1.79, P < 0.0001]. The alterations in BD and stress distribution correlated with the dorsiflexion and radial deviation angles. In the DRUJ, there was no significant difference in BD between the affected and normal sides. CONCLUSIONS: In dorsally malunited DRFs, the alignment change of the RCJ resulted in high BD-concentration areas and stress distribution on the dorsal side of the radius, which may constitute a precursor for OA.

Idiopathic juvenile osteoporosis-a polygenic disorder?

Idiopathic juvenile osteoporosis (IJO) is a rare condition presenting with vertebral and metaphyseal fractures that affects otherwise healthy prepubertal children. Bone mineral density (BMD) measurements are very low. The primary problem appears to be deficient bone formation, with a failure to accrue bone normally during growth. The onset in childhood suggests IJO is a genetic disorder, and a number of reports indicate that some children carry heterozygous pathogenic variants in genes known to be associated with defective osteoblast function and low bone mass, most commonly LRP5 or PLS3. However, a positive family history is unusual in IJO, suggesting the genetic background can be complex. We describe a young man with classical IJO who was investigated with a bone fragility gene panel and whole genome sequencing. The proband was found to carry four variants in three different genes potentially affecting osteoblast function. From his mother he had inherited mutations in ALPL (p.Asn417Ser) and LRP5 (p.Arg1036Gln), and from his father mutations in LRP5 (p.Asp1551Alsfs*13) and activating transcription factor 4 (ATF4) (p.Leu306Ile). His sister had also inherited the LRP5 (p.Asp1551Alsfs*13) from her father, but not the ATF4 mutation. Their spinal BMD z-scores differed substantially (sister -1.6, father -3.2) pointing to the potential importance of the ATF4 mutation. Activating transcription factor 4 acts downstream from RUNX2 and osterix and plays an important role in osteoblast differentiation and function. This case, together with others recently published, supports the view that IJO can result from clustering of mutations in genes related to osteoblast development and function. Novel genes in these pathways may be involved. Our case also emphasizes the value of detailed study of other family members. After a bone biopsy had excluded a mineralization defect due to hypophosphatasia, the proband was treated with zoledronate infusions with good clinical effect.

Sex-specific association of chronic proton pump inhibitor use with reduced bone density and quality.

CONTEXT: Chronic use of proton pump inhibitors (PPIs) has been associated with an increase in bone fragility. However, evidence on the effect of chronic PPI use on bone density is conflicting, and data on bone microarchitectural quality are scarce. OBJECTIVE: The primary aim of this study was to evaluate whether trabecular bone microarchitecture, assessed by trabecular bone score (TBS), is altered in chronic PPI users. The association between PPI use and bone density was also evaluated as a secondary endpoint. METHODS: We extracted individual patient data from the 2005-2008 cycles of the population-based National Health and Nutrition Examination Survey (NHANES), in which lumbar spine dual-energy X-ray absorptiometry (DXA) scans were acquired. TBS values were calculated from DXA images using a dedicated software. Multivariable linear regression analyses stratified by sex were performed to evaluate the association of chronic PPI use with TBS and bone mineral density (BMD), adjusting for relevant confounders. RESULTS: A total of 7478 subjects were included (3961 men, 3517 women). After adjustment for relevant confounders, chronic PPI use was associated with a worse bone health profile in men, with lower TBS (-0.039, 95%CI:[-0.058, -0.020], p<0.001), lumbar spine T-score (-0.27, 95%CI:[-0.49, -0.05], p=0.018), total hip T-score (-0.20, 95%CI:[-0.39, -0.01], p=0.038), and femoral neck T-score (-0.21, 95%CI:[-0.42, -0.01], p=0.045). Notably, the association between chronic PPI use and degraded TBS remained statistically significant even after further adjustment for BMD at lumbar spine and femoral neck (-0.026, 95%CI:[-0.039, -0.012], p=0.001). In contrast, no significant association was observed between chronic PPI use and either TBS or BMD in women. CONCLUSIONS: Chronic PPI use is associated with degraded trabecular bone quality in men, even after adjustment for BMD. No association was observed in women.

Somatic Structure and Ultrasound Parameters of the Calcaneus Bone in Combat Sports Athletes in Relation to Vitamin D3 Levels.

Background/Objectives: Physical activity is widely recognized for its beneficial effects on bone density during adolescence, which could lead to enhanced bone density in later life, thus acting as a health-promoting activity with long-lasting implications. However, not all studies are conclusive regarding the type, intensity, duration, and frequency of the most effective physical activities. This study focuses on combat sports athletes and examines the relationship between their somatic build and heel bone parameters using ultrasound (USG) and their vitamin D3 levels. Methods: The study included 40 male athletes specializing in various combat sports. The measurements of body height, body mass, skinfold thickness, and bone widths at multiple sites were performed to estimate the somatic build. The USG parameters of the heel bone and the blood levels of vitamin D3 were also recorded. Statistical significance was determined using one-way ANOVA, with differences among sports disciplines also examined. Results: The study found significant differences in the body composition and USG bone parameters among athletes from different combat sports (p ≤ 0.05). The calcaneus stiffness index (SI) and speed of sound (SOS) were significantly higher in athletes with normal vitamin D3 levels compared to those with below-normal levels (p = 0.0015 and p = 0.001, respectively). These findings suggest that vitamin D3 may influence bone stiffness and density. Conclusions: The study underscores the importance of maintaining adequate vitamin D3 levels to support bone mineralization in athletes, particularly those training indoors with limited exposure to sunlight. It also highlights the potential of using USG as a non-invasive method to assess bone health, aiding in the optimization of training programs to prevent injuries and improve performance.

Imaging bone turnover assessment through volumetric density-adjusted standardized uptake value using quantitative bone SPECT/CT in osteoporosis.

BACKGROUND: Serum bone turnover markers offer limited insight into metabolic activity at the individual vertebra level in osteoporosis. This study introduces a novel image-derived bone turnover marker for individual vertebrae to address this limitation, utilizing volumetric density-adjusted quantitative bone single-photon emission computed tomography/computed tomography (SPECT/CT) with [99mTc]Tc-DPD. This retrospective study included 177 lumbar vertebrae from 55 postmenopausal South Korean women. The mean standardized uptake value (SUVmean, g/cm3) and volumetric bone mineral density (vBMD, mg/cm3) were determined within a 2-cm³ volume of interest in the trabecular portion of each vertebra using quantitative SPECT and CT. The density-adjusted mean standardized uptake value (dSUVmean) was calculated by dividing the SUVmean by the vBMD and multiplying by 1,000. RESULTS: SUVmean correlated positively with vBMD (r = 0.60, p < 0.001). Conversely, dSUVmean correlated negatively with vBMD (ρ = -0.66, p < 0.001), highlighting the inverse relationship between bone mass and turnover after density adjustment of SUVmean. Patients with major osteoporotic fractures had lower vBMD (62.5 ± 29.4 vs. 92.3 ± 27.4 mg/cm³, p = 0.001) but higher dSUVmean (100.8 ± 60.7 vs. 62.6 ± 17.5, p = 0.001) compared to those without fractures, reinforcing the association between fracture prevalence, low bone mass, and high bone turnover. CONCLUSION: Volumetric density-adjusted quantitative bone SPECT/CT offers a novel image-derived bone turnover marker for assessing bone turnover in osteoporosis. This method provides a precise assessment of fragility at the individual vertebra level, which may enhance personalized osteoporosis management.