In conventional DXA (Dual-energy X-ray Absorptiometry) analysis, pixel bone mineral density (BMD) is often averaged at the femoral neck. Neck BMD constitutes the basis for osteoporosis diagnosis and fracture risk assessment. This data averaging, however, limits our understanding of localised spatial BMD patterns that could potentially enhance fracture prediction. DXA region free analysis (RFA) is a validated toolkit for pixel-level BMD analysis. We have previously deployed this toolkit to develop a spatio-temporal atlas of BMD ageing in the femur. This study aims first to introduce bone age to reflect the overall bone structural evolution with ageing, and second to quantify fracture-specific patterns in the femur. The study dataset comprised 4933 femoral DXA scans from White British women aged 75 years or older. The total number of fractures was 684, of which 178 were reported at the hip within a follow-up period of five years. BMD maps were computed using the RFA toolkit. For each BMD map, bone age was defined as the age for which the L2-norm between the map and the median atlas at that age is minimised. Next, bone maps were normalised for the estimated bone age. A t-test followed by false discovery rate (FDR) analysis was applied to compare between fracture and non-fracture groups. Excluding the ageing effect revealed subtle localised patterns of loss in BMD oriented in the same direction as principal tensile curves. A new score called f-score was defined by averaging the normalised pixel BMD values over the region with FDR q-value less than 1e–6. The area under the curve (AUC) was 0.731 (95% confidence interval (CI)=0.689–0.761) and 0.736 (95% CI=0.694–0.769) for neck BMD and f-score. Combining bone age and f-score improved the AUC significantly by 3% (AUC=0.761, 95% CI=0.756–0.768) over the neck BMD alone (AUC=0.731, 95% CI=0.726–0.737). This technique shows promise in characterizing spatially-complex BMD changes, for which the conventional region-based technique is insensitive. DXA RFA shows promise to further improve fracture prediction using spatial BMD distribution

Introduction: Osteoporosis is one of the major diseases worldwide, affecting millions of elderly people, with severe economical and medical consequences. The most commonly used method for the determination of decreased bone quality is the assessment of Bone Mineral Density, measured by dual X-ray absorptiometry (DXA). However DXA is quantitative and not qualitative index of the bone structure. The purpose of this study was to correlate the bone mineral density measured by DXA with the mechanical properties of the femoral neck. Materials and Methods: Bone mineral density of the proximal femur of 30 patients (27 women, 3 men) undergoing total hip displacement was estimated by DXA. The average age of these patients was 63.7 years. Patients with sort femoral neck or previous surgeries in proximal femur were excluded from the study. After hip replacement bone samples (femoral head and neck) were frozen and stored at −60 °C. A plane bone slice with 6mm thickness was sawed of femoral neck using a double cutting saw. The exact specimen dimensions were measured using a sliding calliper with high accuracy. All bone specimens were destructively tested on a material testing machine, in order to determine the material properties (Young’s modulus and yield stress) of the samples. The maximum available compression load was 100 kN with a load rate of 10 kN/min. The operational parameters and experimental data were fully controlled and handled by a graphical software package. Finally all data were evaluated and statistically analyzed. Results: A strong linear correlation of bone mineral density (T-score) with maximum failure load of samples was noted (R2=0.852). No significant differences in Young’s modulus values, was found between bone samples. Conclusions: Bone mineral density measured by DXA, although has limitations, remain a strong predictor of bone strength in the femoral neck region

Introduction: Heterotopic ossification (HO) is common post total hip replacement. Dual energy x-ray absorptiometery (DXA) is an established technique used to assess peri-prosthetic, bone mineral density (BMD) changes in the femur following surgery. The effect of HO on these measurements has not previously been reported. In this study we investigated the incidence and distribution of HO and the extent to which it affected peri-prosthetic DXA results. Methods: As part of a two-year, prospective, primary cemented THR trial, 137 patients were assessed at six month intervals with DXA as well as anterior-posterior and lateral radiographs. HO was identified from radiographs and then further localised to the seven femoral Gruen zones using DXA subtraction imaging. Results: HO affected at least one Gruen zone in 46% of study patients. The mean BMD in zone 1 dropped to 89% of the postoperative value in unaffected patients by six months whereas it actually increased to 102% in the HO patients (p< 0.001). This 12% difference persisted throughout the duration of the trial. Zone two was affected in 17 patients and a significant gain of 5% was noted in these patients at 12 months (p< 0.05). From observation of AP x-rays alone, 12% of the HO cases would have been missed. HO was found to be significantly associated with male gender and increasing age at time of operation. Surgical approach to the hip also had an effect, osteotomies producing a greater incidence of HO formation. Discussion: HO has a dramatic effect on BMD values determined by DXA. This has not previously been reported and may have affected other peri-prosthetic studies. We recommend careful screening for HO when reporting femoral peri-prosthetic BMD changes

Introduction: Bone resorption in the proximal femur is commonly seen after cementless total hip arthroplasty (THA). One of the main determinants of bone remodeling seems to be prosthesis design. With DXA, the amount of bone mass after THA can be precisely determined. We evaluated the BMD behavior of two different ultra-short implants with proximal load transfer, in order to study how a design can affect femoral bone remodeling. The rationale behind these designs is the experimental evidence that loading the medial and the lateral flare effectively preserves in time metaphyseal bone stock. Moreover, biomechanical tests have confirmed that this kind of stress distribution allows to remove the diaphyseal portion of the stem. Methods: A total of 33 patients operated with a cementless femoral implant were included in this study. Two slightly different designs were tested: Type 1 (Stanmore Orthopaedics), featuring an extremely short distal stem (n=10), and Type 2 (DePuy International Ltd), where distal stem was virtually absent (n=23). All implants were customized based on pre-operative CT data. The main features of these implants were the ultra-short stem and the large lateral flare. The rationale was to preserve bone stock and gain a more physiologic load transfer to the proximal femur thus preventing stress-shielding. DXA examination was performed on all patients 3 years after THA. Due to the peculiar design, a specific protocol of analysis with five regions of interest (ROI) was developed: ROI1 (greater trochanter), ROI2 and ROI4 (respectively lateral and medial of the ultra-short stem), ROI3 (below the tip) and ROI5 (calcar). The same protocol was applied to the non-operated contralateral femur and percentage contralateral BMD was calculated with the following formula: (BMD of operated hip/BMD of contralateral hip)×100. A standard DXA of contralateral hip and lumbar spine was also performed to evaluate the skeletal bone mineralization. Results: No differences were found in the anthropometric data and sex between the two groups. Age was found lower (p=0.001) in Type 2. BMD of lumbar spine and contralateral femur from standard DXA were not different in the two groups. BMD was higher in Type 2 in ROI4 and ROI5 (p< 0.001). The calculated percentage contralateral BMD was higher in Type 2 in ROI2 (p=0.009), ROI4 (p< 0.001) and ROI5 (p=0.01). Conclusions: This study confirms that progressive shortening of femoral stem produces a more proximal loading, which effectively preserves in time metaphyseal bone stock and increases periprosthetic BMD in the medial ROIs. The increased BMD in periprosthetic lateral and medial proximal regions in the operated hip respect to the contralateral femur seems to be due not only to the increased weight-bearing, but also to the specific ultra-short stem design

Introduction A wide range of stress-shielding phenomena following THA have been described in the past 20 years. Bone densitometry (DXA) stars as a golden standard in evaluating bone stock and bone density redistribution after total hip replacement. In this study, DXA scan was employed to evaluate and compare the behaviour of different femoral components including a recently developed stemless implant which features complete stress transfer over the proximal femur. Methodology A total of 120 patients, operated with six different femoral implants, were included in the present study. Five of these stems are widely commercially available (ABG, CFP, IPS, Mayo, Zweymueller) and present different patterns of stress distribution. The sixth is a custom made implant and features a pronounced lateral flare and complete femoral neck preservation. Rationale of this design is to obtain full load transfer on the proximal femur. Average interval between the operation and the DXA exam was 3 years, each group included 20 patients. Bone mineral density was measured by DXA in the seven Gruen femoral regions (ROI), using the software metal removal (Hologic QDR 4500 W, MA-USA). Results Differences in bone density were found in each group as well as between different groups. Significant differences (p< 0.001) were found between the stemless implant and the other five groups in zone I, IV and VII. CFP, IPS and ABG groups showed decreased bone density in ROI I, while Mayo, IPS, ABG and Zweym-ueller were osteopenic in ROI VII. An increased bone density in ROI IV was found in Zweymueller, Mayo, ABG and IPS groups. Conclusion Our data suggest that a conservative stemless implant with complete proximal load transfer, produces a homogeneous and more physiologic redistribution of bone density, allowing maintenance of proximal periprosthetic bone stock

Aim: A study to compare bone remodeling (BMD changes) around the femoral component of a cemented and uncemented THR using DXA scan and Finite element analysis and to check the predictive value of remodelling simulations as a pre-clinical implant testing tool. Methods: Twenty patients were recruited, ten for each implant type (Exeter and ABG-II). All volunteers underwent unilateral hip replacement. No patient had any metabolic bone disease or were on medication that would alter BMD. Each patient had a preopera-tive CT scan of the hip, in order to provide 3D bone shape and density data needed to construct a computer model. Each patient’s changes of BMD over a period of 12 months postoperatively were evaluated in a series of 4 follow-up DXA scans taken at 3 weeks, 3, 6 and 12 months post-op. For the computer simulation, Finite Element (FE) models of the affected femur were constructed for each patient and BMD changes predicted using strain adaptive bone remodelling theory. These patients were clinical followed up to access the hip scores (Merle d’Aubigne Postel). Results: All the patients were Charnely group A and had excellent postoperative hip scores (average pain 5.5, walking 5.4 and range of motion 5.3) The Exeter stem DXA results show bone resorption in Gruen zone 3 (2.8% on average) and 4 (3.3%) whereas there is a tendency for bone deposition at regions 1, 6 and 7 (2% on average). The ABG-II stem results show bone resorption developing at regions 7 and 4 (6% and 2% respectively) and some bone formation at region 6 (2%). The simulation results have a tendency to overestimate amounts of bone resorption (20% at region 7 for the ABG-II, 12% at region 3 for the Exeter). Conclusion: A comparison of the remodelling around a cemented and a non-cemented hip implant show important differences in the emerging patterns of adaptation. To our knowledge, very few published studies provide information on bone remodelling around cemented stems, and compare the results to those of an uncemented stem. Additionally, the simulation results suggest that these formulations can reproduce realistic patterns of bone adaptation. This study aims at providing the means for comparison and subsequent improvement of the accuracy of the simulations and thus helps develop a hip prosthesis that would led to least bone resorption

We evaluated an anatomical uncemented stem, SP-CL, (Static Physiologicus – CementLess) designed to facilitate insertion and to avoid stress concentration at solitary contact points in a randomized controlled trial, with use of the Corail stem as control. The SPÅ-Cl stem has been on the market since 2014 but is still not well documented. 79 patients (80 hips) were primarily recruited and 71 patients (72 hips, 36 SP-CL, 36 Corail) attended the last follow up at 2 years. The clinical evaluation included several types of PROMs with Oxford Hip Score (OHS) as primary outcome. In addition, repeated measurements of stem migration, changes in bone mineral density and development of radiolucencies were studied with RSA, DXA and conventional radiography. At two years the Oxford Hip Score did not differ between the SP-CL and Corail stem (estimated mean difference: −0.70 (95% CI: −4.28 – 2.89). In both groups Oxford hip score had almost doubled at 3 months, continued to increase up to 6 months and was about equal at 2 years (SP-CL; median 46 (17–48), Corail; median 47 (19–48)). At 2 years the SP-CL stems showed a median distal migration of −0.23 (−5.2 – 0.1) and the Corail stems of − 0.11 (−4.4 – 0.4). The SP-CL stems showed slightly more loss of bone mineral density in Gruen region 7 (p = 0.003). We found no difference in clinical results with use of either of the two stems. Bone mineral density loss tended to be higher with use of the SP-CL stem and the early subsidence tended to be more pronounced, which turned out to be compatible with about the same stem stability reached between 1 and 2 years. As a next step we think that the SP-CL stem should be studied in a multi-center setting, before accepted for general use

Aim: Stress-shielding is a common problem after uncemented THA that may lead to proximal femoral atrophy and consecutive aseptic loosening. Methods: In 143 patients with 154 uncemented CLS-stems periprosthetic bone mineral density (BMD) was measured using DXA after a mean of 12 years (10–15) postoperatively (T1). Five years later the same group of patients was examined at a mean of 17 years (range: 15–20) (T2) using the identical protocol. Results: We obtained a complete prospective set of data of two consecutive DXA measurements in 76 cases (32 men, 44 women). In all cases regular bone ongrowth did occur and there were no signs of radiographic loosening (T1 and T2). On radiographic evaluation there was no significant change in periprosthetic bone formation in all Gruen zones between T1 and T2. There was no significant change in activity and BMD. In male patients we found no significant changes in periprosthetic BMD (netavg T1–T2: −1,19%, p< 0,01), in female patients there was no significant difference either (netavg T1–T2: −1,32%,p< 0,01). We analyzed the differences in BMD in all Gruen zones (zone 1–7) comparing T1 and T2 and found no significant differences in any zone (p< 0,01). Conclusion: This study showed that there is no significant change in periprosthetic bone mineral density in the long term using the uncemented CLS stem. There was not a single case of stress shielding in the long term. Once osseous integration has occurred the periprostethic BMD changes remain minimal in the long term

In a previous report from a randomised study we reported excellent fixation and less proximal periprosthetic bone mineral loss around the Epoch design at 2 years follow-up when compared with a solid stem of similar design. We now present the 7 years follow-up. Forty consecutive patients (20 men, 10 women, mean age 57, 41–74) with non-inflammatory osteoarthritis were randomised to receive either a cementless porous-coated composite stem with reduced stiffness (Epoch) or a cementless stiff stem with a porous coating (Anatomic). Patients were followed for 7 years with repeated evaluations using radiostereometry, DXA, conventional radiography and Harris Hip Score (HHS). At 7 years 1 stem had been revised (Anatomic) due to late infection. Subsidence and stem rotations were close to zero without any difference between the two groups (p> 0,12). Median wear rates were lower than expected (0.4mm up to 7 years) for both stem designs. At 2 years loss bone mineral density was less in Gruen regions 1, 2, 6 and 7 for the Epoch stems (p< 0.04), but this difference tended to disappear with time. At 7 years only the calcar region (Gruen region 7) had significantly denser bone in the Epoch group (p< 0.001). The HHS scores did not differ (median 98, 51–100). No stem was radiographically loose. The Epoch stem achieved excellent fixation. Wear rates were low despite use of conventionally gamma-sterilised polyethylene. This low modulus stem had positive effects on early proximal bone remodeling, but this effect decreased with time

Aims. Assessment of bone mineral density (BMD) with dual-energy X-ray absorptiometry (DXA) is a well-established clinical technique, but it is not available in the acute trauma setting. Thus, it cannot provide a preoperative estimation of BMD to help guide the technique of fracture fixation. Alternative methods that have been suggested for assessing BMD include: 1) cortical measures, such as cortical ratios and combined cortical scores; and 2) aluminium grading systems from preoperative digital radiographs. However, limited research has been performed in this area to validate the different methods. The aim of this study was to investigate the evaluation of BMD from digital radiographs by comparing various methods against DXA scanning. Methods. A total of 54 patients with distal radial fractures were included in the study. Each underwent posteroanterior (PA) and lateral radiographs of the injured wrist with an aluminium step wedge. Overall 27 patients underwent routine DXA scanning of the hip and lumbar spine, with 13 undergoing additional DXA scanning of the uninjured forearm. Analysis of radiographs was performed on ImageJ and Matlab with calculations of cortical measures, cortical indices, combined cortical scores, and aluminium equivalent grading. Results. Cortical measures showed varying correlations with the forearm DXA results (range: Pearson correlation coefficient (r) = 0.343 (p = 0.251) to r = 0.521 (p = 0.068)), with none showing statistically significant correlations. Aluminium equivalent grading showed statistically significant correlations with the forearm DXA of the corresponding region of interest (p < 0.017). Conclusion. Cortical measures, cortical indices, and combined cortical scores did not show a statistically significant correlation to forearm DXA measures. Aluminium-equivalent is an easily applicable method for estimation of BMD from digital radiographs in the preoperative setting. Cite this article: Bone Joint Res 2021;10(12):830–839

Aims. The distal radius is a major site of osteoporotic bone loss resulting in a high risk of fragility fracture. This study evaluated the capability of a cortical index (CI) at the distal radius to predict the local bone mineral density (BMD). Methods. A total of 54 human cadaver forearms (ten singles, 22 pairs) (19 to 90 years) were systematically assessed by clinical radiograph (XR), dual-energy X-ray absorptiometry (DXA), CT, as well as high-resolution peripheral quantitative CT (HR-pQCT). Cortical bone thickness (CBT) of the distal radius was measured on XR and CT scans, and two cortical indices mean average (CBTavg) and gauge (CBTg) were determined. These cortical indices were compared to the BMD of the distal radius determined by DXA (areal BMD (aBMD)) and HR-pQCT (volumetric BMD (vBMD)). Pearson correlation coefficient (r) and intraclass correlation coefficient (ICC) were used to compare the results and degree of reliability. Results. The CBT could accurately be determined on XRs and highly correlated to those determined on CT scans (r = 0.87 to 0.93). The CBTavg index of the XRs significantly correlated with the BMD measured by DXA (r = 0.78) and HR-pQCT (r = 0.63), as did the CBTg index with the DXA (r = 0.55) and HR-pQCT (r = 0.64) (all p < 0.001). A high correlation of the BMD and CBT was observed between paired specimens (r = 0.79 to 0.96). The intra- and inter-rater reliability was excellent (ICC 0.79 to 0.92). Conclusion. The cortical index (CBTavg) at the distal radius shows a close correlation to the local BMD. It thus can serve as an initial screening tool to estimate the local bone quality if quantitative BMD measurements are unavailable, and enhance decision-making in acute settings on fracture management or further osteoporosis screening. Cite this article: Bone Joint Res 2021;10(12):820–829

To evaluate the effects of 6 and 18 months of abaloparatide (ABL) compared with placebo (PBO) on bone mineral density (BMD) in the acetabular regions of postmenopausal women with osteoporosis (OP). Acetabular bone loss, as may occur in OP, increases risk of acetabular fragility fractures. a. In total hip arthroplasty (THA), low acetabular BMD adversely affects primary stability, osseointegration, and migration of acetabular cups. c. ABL is an osteoanabolic agent for the treatment of men and postmenopausal women with OP at high risk for fracture. Effects of ABL on acetabular BMD are unknown. Hip DXA scans were obtained at baseline, 6, and 18 months from a random subgroup of postmenopausal women (aged 49–86 y) from the phase 3 ACTIVE trial randomized to either ABL 80 µg/d or PBO (n=250/group). Anatomical landmarks were identified in each DXA scan to virtually place a hemispherical shell model of an acetabular cup and define regions of interest corresponding to DeLee & Charnley zones 1 (R1), 2 (R2), and 3 (R3). BMD changes compared to baseline were calculated for each zone. Statistical P values were based on a repeated mixed measures model. BMD in all zones were similar at baseline in the ABL and PBO groups. BMD significantly increased in the ABL group at 6 and 18 months compared with PBO (all P<0.0001 vs PBO). BMD in the PBO group was relatively stable over time. ABL treatment resulted in rapid and progressive increases in BMD of all 3 acetabular zones. Increasing acetabular BMD has the potential to improve acetabular strength, which may reduce risk of acetabular fragility fractures. In bone health optimization prior to THA, increased acetabular BMD via ABL may provide better primary stability and longevity of acetabular cups in postmenopausal women with OP

Objectives. The aim of the current study was to assess whether calcaneal broadband ultrasound attenuation (BUA) can predict whole body and regional dual-energy x-ray absorptiometry (DXA)-derived bone mass in healthy, Australian children and adolescents at different stages of maturity. Methods. A total of 389 boys and girls across a wide age range (four to 18 years) volunteered to participate. The estimated age of peak height velocity (APHV) was used to classify children into pre-, peri-, and post-APHV groups. BUA was measured at the non-dominant heel with quantitative ultrasonometry (QUS) (Lunar Achilles Insight, GE), while bone mineral density (BMD) and bone mineral content (BMC) were examined at the femoral neck, lumbar spine and whole body (DXA, XR-800, Norland). Associations between BUA and DXA-derived measures were examined with Pearson correlations and linear regression. Participants were additionally ranked in quartiles for QUS and DXA measures in order to determine agreement in rankings. Results. For the whole sample, BUA predicted 29% of the study population variance in whole body BMC and BMD, 23% to 24% of the study population variance in lumbar spine BMC and BMD, and 21% to 24% of the variance in femoral neck BMC and BMD (p < 0.001). BUA predictions were strongest for the most mature participants (pre-APHV R. 2. = 0.03 to 0.19; peri-APHV R. 2. = 0.05 to 0.17; post-APHV R. 2. = 0.18 to 0.28) and marginally stronger for girls (R. 2. = 0.25-0.32, p < 0.001) than for boys (R. 2. = 0.21-0.27, p < 0.001). Agreement in quartile rankings between QUS and DXA measures of bone mass was generally poor (27.3% to 38.2%). Conclusion. Calcaneal BUA has a weak to moderate relationship with DXA measurements of bone mass in children, and has a tendency to misclassify children on the basis of quartile rankings. Cite this article: B. K. Weeks, R. Hirsch, R. C. Nogueira, B. R. Beck. Is calcaneal broadband ultrasound attenuation a valid index of dual-energy x-ray absorptiometry-derived bone mass in children? Bone Joint Res 2016;5:538–543. DOI: 10.1302/2046-3758.511.BJR-2016-0116.R1

Low-energy fractures complications are a major public health issue that make osteoporosis even worse. In sub-Saharan Africa, the prevalence of osteoporosis varies from 18.2% to 65.8%. There was no change in bone mineral density between HIV-infected and non-HIV-infected women in Sub-Saharan Africa, where HIV is widespread. Other investigations that demonstrated that HIV-infected people had poor BMD both before and after starting anti-retroviral treatment did not consistently show a low BMD finding. Inflammation-mediated bone remodelling has been associated with low BMD in HIV-infected patients. Antiretroviral Therapy has been demonstrated to exacerbate bone loss in addition to the pre-existing intrinsic risk of developing osteoporosis. Question: Is there loss of bone in HIV-infected patients before initiating ART?. The patients who were HIV-positive and enrolled in the ADVANCE research were retrospectively reviewed on a desk. All of the 1053 individuals in the ADVANCE research had a DXA scan performed to evaluate BMD as part of the initial screening and recruitment approach. The ADVANCE research enrolled HIV-positive people and randomly assigned them to three ART arms. A total of 400 patients were reviewed. Of these 400 records reviewed, 62.3% were female. 80% of the participants were younger than 40 years old, and 3% were older than 50 years. 82% were virally suppressed with less than 50 viral copies. The prevalence of osteopenia was 25.5% and osteoporosis was 2.8%, observed in predominantly African female participants aged between 30 and 39 years. The findings of this study confirm that there is pre-existing bone loss among HIV-infected ART naïve individuals. Approximately 28.3% in our study had clinically confirmed evidence of bone loss and of these, 2.8% of the entire cohort had osteoporosis. Bone loss was most prevalent in black females who are virologically suppressed

Quantitative ultrasound (QUS) is a promising tool to estimate bone structure characteristics and predict fragile fracture. The aim of this pilot cross-sectional study was to evaluate the performance of a multi-channel residual network (MResNet) based on ultrasonic radiofrequency (RF) signal to discriminate fragile fractures retrospectively in postmenopausal women. Methods. RF signal and speed of sound (SOS) were obtained using an axial transmission QUS at one‐third distal radius for 246 postmenopausal women. Based on the involved RF signal, we conducted a MResNet, which combines multi-channel training with original ResNet, to classify the high risk of fragility fractures patients from all subjects. The bone mineral density (BMD) at lumber, hip and femoral neck acquired with DXA was recorded on the same day. The fracture history of all subjects in adulthood were collected. To assess the ability of the different methods in the discrimination of fragile fracture, the odds ratios (OR) calculated using binomial logistic regression analysis and the area under the receiver operator characteristic curves (AUC) were analyzed. Results. Among the 246 postmenopausal women, 170 belonged to the non-fracture group, 50 to the vertebral group, and 26 to the non-vertebral fracture group. MResNet was discriminant for all fragile fractures (OR = 2.64; AUC = 0.74), for Vertebral fracture (OR = 3.02; AUC = 0.77), for non-vertebral fracture (OR = 2.01; AUC = 0.69). MResNet showed comparable performance to that of BMD of hip and lumbar with all types of fractures, and significantly better performance than SOS all types of fractures. Conclusions. the MResNet model based on the ultrasonic RF signal can significantly improve the ability of QUS device to recognize previous fragile fractures. Moreover, the performance of the proposed model modified by age, weight, and height is further optimized. These results open perspectives to evaluate the risk of fragile fracture applying a deep learning model to analyze ultrasonic RF signal

Objective: To examine the relationship between three measurements of bone quality and bone strength of the tibial plateau, and the relationships between these measurements. Methods: The bone quality of sixteen cadaveric tibias was assessed for density and architecture using three methods: DXA, pQCT, and spectral analysis of digitised radiographs. These bone quality measurements were correlated with the þxation strength of a bicondylar plateau fracture, obtained by mechanical testing. Results: All three techniques correlate strongly with the mechanical strength of the þxed tibial plateau, with the highest correlation being with DXA (r=0.81, P< 0.001), and pQCT (r=0.79, P< 0.001); followed by spectral analysis (r= 0.5, P,0.01). DXA correlates strongly with pQCT (r=0.95, P< 0.001); Whereas, spectral analysis has a weaker correlation with both DXA (r=0.65, P< 0.01), and pQCT (r=0.69, P< 0.01). Discussion: This is the þrst study of bone quality assessment in the tibial plateau, and as with studies at other sites, DXA showed that BMD has the best correlation with mechanical failure. Both DXA and pQCT are a reßection of density assessment which explains the strong correlation seen. However, the strength of bone is a function of not just quantity and density but also its structure. This was assessed using spectral analysis which involves image processing and pattern recognition algorithm of the trabecular structure. This measures structure only and this may explain the lower correlation with bone strength. Nevertheless we feel that further analysis may demonstrate a speciþc use of this technique to compliment either DXA or PqCT in providing complete assessment of the bone

In cases of poor bone quality intraoperative torque measurement might be an alternative to preoperative dual energy x-ray absorptiometry (DXA) to assess bone quality in Total Hip Arthroplasty (THA). 14 paired fresh frozen human femurs were included for trabecular peak torque measurement. We evaluated an existing intraoperative torque measurement method to assess bone quality and bone strength. We modified the approach to use this method in total hip arthroplasty (THA), which has not been published before. Since there are several approaches used in THA to exposure the hip joint, we decided to prefer the measurement in the femoral head which allows every surgeon to perform this measurement. Here a 6.5 × 23 mm blade was inserted into the proximal femur without harming the lateral cortical bone (figure 1). Further tests of the proximal femur evaluated the results of this new method: DXA, micro-computed tomography (μCT) and biomechanical load tests. Basic statistical analyses and multiple regressions were done. In the femoral head mean trabecular peak torque was 4.38 ± 1.86 Nm. These values showed a strong correlation with the values of the DXA, the μCT and the biomechanical load test. In comparison to the bone mineral density captured by DXA, the results of the intraoperative torque measurement showed a superior correlation with high sensitive bone quality evaluating methods (mechanical load tests and micro-computed tomography). Hence, the use of this intraoperative torque measurement seems to be more accurate in evaluating bone strength and bone quality than DXA during THA. The torque measurement provides sensitive information about the bone strength, which may affect the choice of implant in cases of poor bone stock and osteoporosis. In clinical use the surgeon may alter the prosthesis if the device indicates poor bone quality. Furthermore, we assume that the disadvantages associated with DXA scans like radiation exposure or errors caused by potential extraosteal sclerosis and interindividual soft-tissue artifacts could be excluded

Objectives. Researchers continue to seek easier ways to evaluate the quality of bone and screen for osteoporosis and osteopenia. Until recently, radiographic images of various parts of the body, except the distal femur, have been reappraised in the light of dual-energy X-ray absorptiometry (DXA) findings. The incidence of osteoporotic fractures around the knee joint in the elderly continues to increase. The aim of this study was to propose two new radiographic parameters of the distal femur for the assessment of bone quality. Methods. Anteroposterior radiographs of the knee and bone mineral density (BMD) and T-scores from DXA scans of 361 healthy patients were prospectively analyzed. The mean cortical bone thickness (CBTavg) and the distal femoral cortex index (DFCI) were the two parameters that were proposed and measured. Intra- and interobserver reliabilities were assessed. Correlations between the BMD and T-score and these parameters were investigated and their value in the diagnosis of osteoporosis and osteopenia was evaluated. Results. The DFCI, as a ratio, had higher reliability than the CBTavg. Both showed significant correlation with BMD and T-score. When compared with DFCI, CBTavg showed better correlation and was better for predicting osteoporosis and osteopenia. Conclusion. The CBTavg and DFCI are simple and reliable screening tools for the prediction of osteoporosis and osteopenia. The CBTavg is more accurate but the DFCI is easier to use in clinical practice. Cite this article: Q-F. He, H. Sun, L-Y. Shu, Y. Zhu, X-T. Xie, Y. Zhan, C-F. Luo. Radiographic predictors for bone mineral loss: Cortical thickness and index of the distal femur. Bone Joint Res 2018;7:468–475. DOI: 10.1302/2046-3758.77.BJR-2017-0332.R1

Introduction: The most widely accepted method for measuring bone mineral density (BMD) is Dual-energy X-ray Absorptionmetry (DXA). However, the need for relatively expensive equipment and trained personnel lower the accessibility of DXA as a routine screening tool. Plain pelvic X-ray radiography is a simple and inexpensive examination. In principal, the gray level of the bone in the X-ray radiograph is related to BMD. However, several factors render plain X-ray radiographs of the hip unsuitable for BMD measurements, mainly the variability in X-ray exposure levels and the soft tissue surrounding the bone. In this study, we aimed to develop new modifications of plain X-ray radiography of the proximal femur. Patients and methods: The study population consisted of 18 women with an average age of 77 years (range 57–96 years) who were hospitalized due to a low-energy fracture of the neck of the femur. Each patient’s contralateral hip was radiographed with an aluminium step-wedge positioned near the hip as a standard reference, using a computerized radiography system. A DXA examination of the same hip followed the plain radiograph. On each radiograph, regions of interest (ROI) were determined in concordance with the ROI of the DXA examination. The mean gray level was measured for each ROI. The neck-shaft angle and the femoral head diameter were also measured. Results: Comparing the gray levels of the plain radiograph with the BMD levels obtained by the DXA revealed a coefficient ratio of R=0.499. Correction of the gray levels using the step wedge as a standard reference revealed a ratio of R=0.576. If further correction was made with measurement of the soft tissue gray levels, a ratio of R=0.708 was obtained. Using the anatomical measurements (neck-shaft angle and femoral head diameter), a ratio of R=0.948 was obtained. Conclusion: This study shows that a plain digital radiograph of the pelvis can provide valuable information concerning the bone mineral content of the proximal femur, which is comparable to the results of the DXA examination. Ultimately, the research can lead to the development of a fast, available and relatively inexpensive technique to diagnose osteoporosis

Introduction. Trabecular bone score (TBS) is a parameter of bone microarchitecture that is determined by the level analysis of DXA images. TBS is associated with fractures in the preliminary case-control and prospective studies. The aim of this study was to assess the TBS role in the traumatology and orthopedics. Materials and methods. We've examined 176 healthy women aged 40–79 years (mean age – 53.4±0.6 yrs) and 117 men aged 40–79 years (mean age – 59.8±0.9 yrs). Bone mineral density (BMD) of whole body, PA lumbar spine and proximal femur were measured by DXA method (Prodigy, GEHC Lunar, Madison, WI, USA) and PA spine TBS were assessed by TBS iNsight® software package installed on the available DXA machine (Med-Imaps, Pessac, France). Results. We have observed a significant decrease of TBS as a function of age (F=6.56; p=0.0003) whereas PA spine BMD was significantly increasing with age (F=4.04; p=0.008) in the examined women. This contradiction can be traced to the spinal osteoarthritis and degenerative diseases progressing with age in the elderly patients. TBS was significantly lower in women with duration of PMP over 4 yrs (p=0.003) in comparison with women without menopause; BMD of spine significantly decreased in women with duration of PMP over 7–9 yrs (p=0.02). So, the TBS can detect changes in the state of bone tissue at the earlier stage than BMD. We have observed a significant decrease of TBS in men with ageing (F=2.44; p=0.05). Overall TBS values in men are lower than the age matched TBS values in women. Conclusion. TBS is an independent parameter which has a potential diagnostic value of its own, without taking into account the BMD results. The study concerning patients with osteoporosis and fractures is underway