Cost-effectiveness analysis of the Geriatric Fracture Center (GFC) concept: a prospective multicentre cohort study

INTRODUCTION

Geriatric Fracture Centers (GFCs) are dedicated treatment units where care is tailored towards elderly patients who have suffered fragility fractures. The primary objective of this economic analysis was to determine the cost-utility of GFCs compared with usual care centres.

METHODS

The primary analysis was a cost-utility analysis that measured the cost per incremental quality-adjusted life-year gained from treatment of hip fracture in GFCs compared with treatment in usual care centres from the societal perspective over a 1-year time horizon. The secondary analysis was a cost-utility analysis from a societal perspective over a lifetime time horizon. We evaluated these outcomes using a cost-utility analysis using data from a large multicentre prospective cohort study comparing GFCs versus usual care centres that took place in Austria, Spain, the USA, the Netherlands, Thailand and Singapore.

RESULTS

GFCs may be cost-effective in the long term, while providing a more comprehensive care plan. Patients in usual care centre group were slightly older and had fewer comorbidities. For the 1-year analysis, the costs per patient were slightly lower in the GFC group (-$646.42), while the quality-adjusted life-years were higher in the usual care centre group (+0.034). The incremental cost-effectiveness ratio was $18 863.34 (US$/quality-adjusted life-year). The lifetime horizon analysis found that the costs per patient were lower in the GFC group (-$7210.35), while the quality-adjusted life-years were higher in the usual care centre group (+0.02). The incremental cost-effectiveness ratio was $320 678.77 (US$/quality-adjusted life-year).

CONCLUSIONS

This analysis found that GFCs were associated with lower costs compared with usual care centres. The cost-savings were greater when the lifetime time horizon was considered. This comprehensive cost-effectiveness analysis, using data from an international prospective cohort study, found that GFC may be cost-effective in the long term, while providing a more comprehensive care plan. A greater number of major adverse events were reported at GFC, nevertheless a lower mortality rate associated with these adverse events at GFC. Due to the minor utility benefits, which may be a result of greater adverse event detection within the GFC group and much greater costs of usual care centres, the GFC may be cost-effective due to the large cost-savings it demonstrated over the lifetime time horizon, while potentially identifying and treating adverse events more effectively. These findings suggest that the GFC may be a cost-effective option over the lifetime of a geriatric patient with hip fracture, although future research is needed to further validate these findings.

LEVEL OF EVIDENCE

Economic, level 2.

TRIAL REGISTRATION NUMBER

NCT02297581.

Risk factors and healthcare costs associated with long bone fracture non-union: a retrospective US claims database analysis

BACKGROUND

Few contemporary US-based long bone non-union analyses have recently been published. Our study was designed to provide a current understanding of non-union risks and costs, from the payers' perspective.

METHODS

The Merative™ MarketScan® Commercial Claims and Encounters database was used. Patients with surgically treated long bone (femur, tibia, or humerus) fractures in the inpatient setting, from Q4 2015 to most recent, were identified. Exclusion criteria included polytrauma and amputation at index. The primary outcome was a diagnosis of non-union in the 12 and 24 months post-index. Additional outcomes included concurrent infection, reoperation, and total healthcare costs. Age, gender, comorbidities, fracture characteristics, and severity were identified for all patients. Descriptive analyses were performed. Crude and adjusted rates of non-union (using Poisson regressions with log link) were calculated. Marginal incremental cost of care associated with non-union and infected non-union and reoperation were estimated using a generalized linear model with log link and gamma distribution.

RESULTS

A total of 12,770, 13,504, and 4,805 patients with femoral, tibial, or humeral surgically treated fractures were identified, 74-89% were displaced, and 18-27% were comminuted. Two-year rates of non-union reached 8.5% (8.0%-9.1%), 9.1% (8.6%-9.7%), and 7.2% (6.4%-8.1%) in the femoral, tibial, and humeral fracture cohorts, respectively. Shaft fractures were at increased risk of non-union versus fractures in other sites (risk ratio (RR) in shaft fractures of the femur: 2.36 (1.81-3.04); tibia: 1.95 (1.47-2.57); humerus: 2.02 (1.42-2.87)). Fractures with severe soft tissue trauma (open vs. closed, Gustilo III vs. Gustilo I-II) were also at increased risk for non-union (RR for Gustilo III fracture (vs. closed) for femur: R = 1.96 (1.45-2.58), for tibia: 3.33 (2.85-3.87), RR for open (vs. closed) for humerus: 1.74 (1.30-2.32)). For all fractures, younger patients had a reduced risk of non-union compared to older patients. For tibial fractures, increasing comorbidity (Elixhauser Index 5 or greater) was associated with an increased risk of non-union. The two-year marginal cost of non-union ranged from $33K-$45K. Non-union reoperation added $16K-$34K in incremental costs. Concurrent infection further increased costs by $46K-$86K.

CONCLUSIONS

Non-union affects 7-10% of surgically treated long bone fracture cases. Shaft and complex fractures were at increased risk for non-union.

Grip strength cut-points from the Swiss DO-HEALTH population

BACKGROUND

While grip strength (GS) is commonly assessed using a Dynamometer, the Martin Vigorimeter was proposed as an alternative method especially in older adults. However, its reference values for Swiss older adults are missing. We therefore aimed to derive sex- and age-specific GS cut-points for the dominant and non-dominant hand (DH; NDH) using the Martin Vigorimeter. Additionally, we aimed to identify clinically relevant weakness and assess convergent validity with key markers of physical function and sarcopenia in generally healthy Swiss older adults.

METHODS

This cross-sectional analysis includes baseline data from Swiss participants enrolled in DO-HEALTH, a 3-year randomized controlled trial in community-dwelling adults age 70 + . For both DH and NDH, 4 different definitions of weakness to derive GS cut-points by sex and age category (≤ 75 vs. > 75 years) were used: i) GS below the median of the 1st quintile, ii) GS below the upper limit of the 1st quintile, iii) GS below 2-standard deviation (SD) of the sex- and age-specific mean in DO-HEALTH Swiss healthy agers (i.e. individuals without major chronic diseases, disabilities, cognitive impairment or mental health issues) and iv) GS below 2.5-SD of the sex- and age-specific mean in DO-HEALTH Swiss healthy agers. To assess the proposed cut-points' convergent validity, we assessed their association with gait speed, time to complete the 5 Times Sit-To-Stand (5TSTS) test, and present sarcopenia.

RESULTS

In total, 976 participants had available GS at the DH (mean age 75.2, 62% women). According to the 4 weakness definitions, GS cut-points at the DH ranged from 29-42 and 25-39 kPa in younger and older women respectively, and from 51-69 and 31-50 kPa in younger and older men respectively. Overall, weakness prevalence ranged from 2.0% to 19.3%. Definitions of weakness using the median and the upper limit of the 1st GS quintile were most consistently associated with markers of physical performance. Weak participants were more likely to have lower gait speed, longer time to complete the 5TSTS, and sarcopenia, compared to participants without weakness.

CONCLUSIONS

In generally healthy Swiss older adults, weakness defined by the median or the upper limit of the 1st GS quintile may serve as reference to identify clinically relevant weakness. Additional research is needed in less healthy populations in order to derive representative population-based cut-points.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01745263.

Precision of bone mechanoregulation assessment in humans using longitudinal high-resolution peripheral quantitative computed tomography in vivo

Local mechanical stimuli in the bone microenvironment are essential for the homeostasis and adaptation of the skeleton, with evidence suggesting that disruption of the mechanically-driven bone remodelling process may lead to bone loss. Longitudinal clinical studies have shown the combined use of high-resolution peripheral quantitative computed tomography (HR-pQCT) and micro-finite element analysis can be used to measure load-driven bone remodelling in vivo; however, quantitative markers of bone mechanoregulation and the precision of these analyses methods have not been validated in human subjects. Therefore, this study utilised participants from two cohorts. A same-day cohort (n = 33) was used to develop a filtering strategy to minimise false detections of bone remodelling sites caused by noise and motion artefacts present in HR-pQCT scans. A longitudinal cohort (n = 19) was used to develop bone imaging markers of trabecular bone mechanoregulation and characterise the precision for detecting longitudinal changes in subjects. Specifically, we described local load-driven formation and resorption sites independently using patient-specific odds ratios (OR) and 99 % confidence intervals. Conditional probability curves were computed to link the mechanical environment to the remodelling events detected on the bone surface. To quantify overall mechanoregulation, we calculated a correct classification rate measuring the fraction of remodelling events correctly identified by the mechanical signal. Precision was calculated as root-mean-squared averages of the coefficient of variation (RMS-SD) of repeated measurements using scan-rescan pairs at baseline combined with a one-year follow-up scan. We found no significant mean difference (p < 0.01) between scan-rescan conditional probabilities. RMS-SD was 10.5 % for resorption odds, 6.3 % for formation odds, and 1.3 % for correct classification rates. Bone was most likely to be formed in high-strain and resorbed in low-strain regions for all participants, indicating a consistent, regulated response to mechanical stimuli. For each percent increase in strain, the likelihood of bone resorption decreased by 2.0 ± 0.2 %, and the likelihood of bone formation increased by 1.9 ± 0.2 %, totalling 38.3 ± 1.1 % of strain-driven remodelling events across the entire trabecular compartment. This work provides novel robust bone mechanoregulation markers and their precision for designing future clinical studies.

Comparing the volume of vascular intersection of two femoral neck fracture fixation implants using an In silico technique

Femoral neck fracture displacement with subsequent vascular disruption is one of the factors that contribute to trauma-induced avascular necrosis of the femoral head. Iatrogenic damage of the intraosseous arterial system during fixation of femoral neck fracture is another possible cause of avascular necrosis that is less well understood. Recently, Zhao et al (2017) reconstructed 3D structures of intraosseous blood supply and identified the epiphyseal and inferior retinacular arterial system to be important structures for maintaining the femoral head blood supply after femoral neck fracture. The authors therefore recommended placing implants centrally to reduce iatrogenic vascular injuries. Our in vitro study compared the spatial footprint of a traditional dynamic hip screw with an antirotation screw versus a newly developed hip screw with an integrated antirotation screw on intraosseous vasculature.

Methods

Three dimensional (3D) µCT angiograms of 9 cadaveric proximal femora were produced. Three segmented volumes-porous or cancellous bone, filled or cortical bone, and intraosseous vasculature-were converted to surface files. 3D in silico models of the fixation systems were sized and implanted in silico without visibility of the vascular maps. The volume of vasculature that overlapped with the devices was determined. The ratio of the vascular intersection to the comparator device was calculated, and the mean ratio was determined. A paired design, noninferiority test was used to compare the devices.

Results

Results indicate both significant (P < 0.001) superiority and noninferiority of the hip screw with an integrated antirotation screw when compared with a dynamic hip screw and antirotation screw for the volume of vasculature that overlapped with each device in the femoral neck.

Conclusions

Combining established methods of vascular visualization with newer methods enables an implant's impact on vascular intersection to be assessed in silico. This methodology suggests that when used for femoral neck fracture management, the new device intersects fewer blood vessels than the comparator. Comparative clinical studies are needed to investigate whether these findings correlate with the incidence of avascular necrosis and clinical outcomes.

Clinical observation of diminished bone quality and quantity through longitudinal HR-pQCT-derived remodeling and mechanoregulation

High resolution peripheral quantitative computed tomography (HR-pQCT) provides methods for quantifying volumetric bone mineral density and microarchitecture necessary for early diagnosis of bone disease. When combined with a longitudinal imaging protocol and finite element analysis, HR-pQCT can be used to assess bone formation and resorption (i.e., remodeling) and the relationship between this remodeling and mechanical loading (i.e., mechanoregulation) at the tissue level. Herein, 25 patients with a contralateral distal radius fracture were imaged with HR-pQCT at baseline and 9-12 months follow-up: 16 patients were prescribed vitamin D3 with/without calcium supplement based on a blood biomarker measures of bone metabolism and dual-energy X-ray absorptiometry image-based measures of normative bone quantity which indicated diminishing (n = 9) or poor (n = 7) bone quantity and 9 were not. To evaluate the sensitivity of this imaging protocol to microstructural changes, HR-pQCT images were registered for quantification of bone remodeling and image-based micro-finite element analysis was then used to predict local bone strains and derive rules for mechanoregulation. Remodeling volume fractions were predicted by both average values of trabecular and cortical thickness and bone mineral density (R² > 0.8), whereas mechanoregulation was affected by dominance of the arm and group classification (p < 0.05). Overall, longitudinal, extended HR-pQCT analysis enabled the identification of changes in bone quantity and quality too subtle for traditional measures.

Effects of vitamin D, omega-3 fatty acids, and a simple home strength exercise program on fall prevention: the DO-HEALTH randomized clinical trial

BACKGROUND

The roles of vitamin D, omega-3 fatty acids, and home exercise on fall prevention among generally healthy and active older adults are unclear.

OBJECTIVES

We tested the effects of daily supplemental vitamin D, daily supplemental marine omega-3s fatty acids, and a simple home exercise program (SHEP), alone or in combination, on the incidences of total and injurious falls among generally healthy older adults.

METHODS

We performed a 2 × 2 × 2 factorial-design randomized controlled trial among 2157 community-dwelling adults aged 70 years and older, who had no major health events in the 5 years prior to enrolment, recruited from Switzerland, Germany, Austria, France, and Portugal between December 2012 and November 2014. Participants were randomly assigned to supplementation with 2000 international units/day of vitamin D3 and/or 1 g/day of marine omega-3s, and/or a SHEP compared with placebo and/or control exercise over 3 years. The primary endpoint for the present fall analysis was the incidence rate of total falls. Falls were recorded prospectively throughout the trial. Since there were no interactions between treatments, the main effects are reported based on a modified intent-to-treat analysis.

RESULTS

Of 2157 randomized participants, 1900 (88%) completed the study. The mean age was 74.9 years, 61.7% were women, 40.7% had a serum 25-hydroxyvitamin D concentration < 20 ng/ml, and 83% were at least moderately physically active. In total, 3333 falls were recorded over a median follow-up of 2.99 years. Overall, vitamin D and the SHEP had no benefit on total falls, whilst supplementation with omega-3s compared to no omega-3 supplementation reduced total falls by 10% (incidence rate ratio = 0.90; 95% CI, 0.81-1.00; P = 0.04).

CONCLUSIONS

Among generally healthy, active, and vitamin D-replete older adults, omega-3 supplementation may have a modest benefit on the incidence of total falls, whilst a daily high dose of vitamin D or a SHEP had no benefit.

Prevalence of healthy aging among community dwelling adults age 70 and older from five European countries

Background

To compare the prevalence of healthy aging among adults age 70 and older from 5 European countries recruited for the DO-HEALTH clinical trial. Participants were selected for absence of prior major health events.

Methods

Cross-sectional analysis of DO-HEALTH baseline data. All 2,157 participants (mean age 74.9, SD 4.4; 61.7% women) were included and 2,123 had data for all domains of the healthy aging status (HA) definition. HA was assessed based on the Nurses` Health Study (NHS) definition requiring four domains: no major chronic diseases, no disabilities, no cognitive impairment (Montreal Cognitive Assessment, MoCA ≥25), no mental health limitation (GDS-5 <2, and no diagnosis of depression). Association between HA and age, BMI, gender, and physical function (sit-to-stand, gait speed, grip strength) was assessed by multivariate logistic regression analyses adjusting for center.

Results

Overall, 41.8% of DO-HEALTH participants were healthy agers with significant variability by country: Austria (Innsbruck) 58.3%, Switzerland (Zurich, Basel, Geneva) 51.2%, Germany (Berlin) 37.6%, France (Toulouse) 36.7% and Portugal (Coimbra) 8.8% (p <0.0001). Differences in prevalence by country persisted after adjustment for age. In the multivariate model, younger age (OR = 0.95, 95% CI 0.93 to 0.98), female gender (OR = 1.36, 95% CI 1.03 to 1.81), lower BMI (OR = 0.94, 95% CI 0.91 to 0.96), faster gait speed (OR = 4.70, 95% CI 2.68 to 8.25) and faster performance in sit-to-stand test (OR = 0.90, 95% CI 0.87 to 0.93) were independently and significantly associated with HA.

Conclusions

Despite the same inclusion and exclusion criteria preselecting relatively healthy adults age 70 years and older, HA prevalence in DO-HEALTH varied significantly between countries and was highest in participants from Austria and Switzerland, lowest in participants from Portugal. Independent of country, younger age, female gender, lower BMI and better physical function were associated with HA.

Trial registration

DO-HEALTH was registered under the protocol NCT01745263 at the International Trials Registry (clinicaltrials.gov), and under the protocol number 2012–001249-41 at the Registration at the European Community Clinical Trial System (EudraCT).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-02755-8.

Simplified Mechanical Tests Can Simulate Physiological Mechanics of a Fixation Construct for Periprosthetic Femoral Fractures

Plate fractures after fixation of a Vancouver Type B1 periprosthetic femoral fracture (PFF) are difficult to treat and could lead to severe disability. However, due to the lack of direct measurement of in vivo performance of the PFF fixation construct, it is unknown whether current standard mechanical tests or previous experimental and computational studies have appropriately reproduced the in vivo mechanics of the plate. To provide a basis for the evaluation and development of appropriate mechanical tests for assessment of plate fracture risk, this study applied loads of common activities of daily living (ADLs) to implanted femur finite element (FE) models with PFF fixation constructs with an existing or a healed PFF. Based on FE simulated plate mechanics, the standard four-point-bend test adequately matched the stress state and the resultant bending moment in the plate as compared with femur models with an existing PFF. In addition, the newly developed constrained three-point-bend tests were able to reproduce plate stresses in models with a healed PFF. Furthermore, a combined bending and compression cadaveric test was appropriate for risk assessment including both plate fracture and screw loosening after the complete healing of PFF. The result of this study provides the means for combined experimental and computational preclinical evaluation of PFF fixation constructs.

Angular stable locking in a novel intramedullary nail improves construct stability in a distal tibia fracture model

INTRODUCTION

Intramedullary nails are frequently used for treatment of unstable distal tibia fractures. However, insufficient fixation of the distal fragment could result in delayed healing, malunion or nonunion. Recently, a novel concept for angular stable nailing was developed that maintains the principle of relative stability and introduces improvements expected to reduce nail toggling, screw migration and secondary loss of reduction. The aim of this study was to investigate the biomechanical competence of the novel angular stable intramedullary nail concept for treatment of unstable distal tibia fractures, compared to a conventional nail locking in a human cadaveric model under dynamic loading.

MATERIALS AND METHODS

Ten pairs of fresh-frozen human cadaveric tibiae with a simulated AO/OTA 42-A3.1 fracture were assigned to 2 groups for reamed intramedullary nailing using either a conventional (non-angular stable) Expert Tibia Nail (ETN) with 3 distal screws or the novel Tibia Nail Advanced (TNA) system with 2 distal angular stable locking low-profile retaining screws. The specimens were biomechanically tested under conditions including initial quasi-static loading, followed by progressively increasing combined cyclic axial and torsional loading in internal rotation until failure of the bone-implant construct. Both tests were monitored by means of motion tracking.

RESULTS

Initial nail toggling of the distal tibia fragment in varus and flexion under axial loading was lower for TNA compared to ETN, being significant in flexion, P = 0.91 and P = 0.03. After 5000 cycles, interfragmentary movements in terms of varus, flexion, internal rotation, axial displacement, and shear displacement at the fracture site were all lower for TNA compared to ETN, with flexion and shear displacement being significant, P = 0.14, P = 0.04, P = 0.25, P = 0.11 and P = 0.04, respectively. Cycles to failure until both interfragmentary 5° varus and 5° flexion were significantly higher for TNA compared to ETN, P = 0.04.

CONCLUSION

From a biomechanical perspective, the novel angular stable intramedullary nail concept provides increased construct stability and maintains it over time while reducing the number of required locking screws without impeding the flexibility of the nail itself and resists better towards loss of reduction under dynamic loading, compared to conventional locking in intramedullary nailed unstable distal tibia fractures.

Prevalence of Physical Frailty: Results from the DO-HEALTH Study

BACKGROUND

Frailty is a geriatric syndrome associated with multiple negative health outcomes. However, its prevalence varies by population and instrument used. We investigated frailty and pre-frailty prevalence by 5 instruments in community-dwelling older adults enrolled to a randomized-controlled trial in 5 European countries.

METHODS

Cross-sectional baseline analysis in 2,144 DO-HEALTH participants recruited from Switzerland, Austria, France, Germany, and Portugal with complete data for frailty. Frailty status was assessed by the Physical Frailty Phenotype [PFP], SOF-Frailty Index [SOF-FI], FRAIL-Scale, SHARE-Frailty Instrument [SHARE-FI], and a modified SHARE-FI, and compared by country, age, and gender. Logistic regression was used to determine relevant factors associated with frailty and pre-frailty.

RESULTS

Mean age was 74.9 (±4.4) years, 61.6% were women. Based on the PFP, overall frailty and pre-frailty prevalence was 3.0% and 43.0%. By country, frailty prevalence was highest in Portugal (13.7%) and lowest in Austria (0%), and pre-frailty prevalence was highest in Portugal (57.3%) and lowest in Germany (37.1%). By instrument and overall, frailty and pre-frailty prevalence was highest based on SHARE-FI (7.0% / 43.7%) and lowest based on SOF-FI (1.0% / 25.9%). Frailty associated factors were residing in Coimbra (Portugal) [OR 12.0, CI 5.30-27.21], age above 75 years [OR 2.0, CI 1.17-3.45], and female gender [OR 2.8, CI 1.48-5.44]. The same three factors predicted pre-frailty.

CONCLUSIONS

Among relatively healthy adults age 70 and older enroled to DO-HEALTH, prevalence of frailty and pre-frailty differed significantly by instrument, country, gender, and age. Among instruments, the highest prevalence of frailty and pre-frailty was documented by the SHARE-FI and the lowest by the SOF-FI.

Bone Mechanoregulation Allows Subject-Specific Load Estimation Based on Time-Lapsed Micro-CT and HR-pQCT in Vivo

Patients at high risk of fracture due to metabolic diseases frequently undergo long-term antiresorptive therapy. However, in some patients, treatment is unsuccessful in preventing fractures or causes severe adverse health outcomes. Understanding load-driven bone remodelling, i.e., mechanoregulation, is critical to understand which patients are at risk for progressive bone degeneration and may enable better patient selection or adaptive therapeutic intervention strategies. Bone microarchitecture assessment using high-resolution peripheral quantitative computed tomography (HR-pQCT) combined with computed mechanical loads has successfully been used to investigate bone mechanoregulation at the trabecular level. To obtain the required mechanical loads that induce local variances in mechanical strain and cause bone remodelling, estimation of physiological loading is essential. Current models homogenise strain patterns throughout the bone to estimate load distribution in vivo, assuming that the bone structure is in biomechanical homoeostasis. Yet, this assumption may be flawed for investigating alterations in bone mechanoregulation. By further utilising available spatiotemporal information of time-lapsed bone imaging studies, we developed a mechanoregulation-based load estimation (MR) algorithm. MR calculates organ-scale loads by scaling and superimposing a set of predefined independent unit loads to optimise measured bone formation in high-, quiescence in medium-, and resorption in low-strain regions. We benchmarked our algorithm against a previously published load history (LH) algorithm using synthetic data, micro-CT images of murine vertebrae under defined experimental in vivo loadings, and HR-pQCT images from seven patients. Our algorithm consistently outperformed LH in all three datasets. In silico-generated time evolutions of distal radius geometries (n = 5) indicated significantly higher sensitivity, specificity, and accuracy for MR than LH (p < 0.01). This increased performance led to substantially better discrimination between physiological and extra-physiological loading in mice (n = 8). Moreover, a significantly (p < 0.01) higher association between remodelling events and computed local mechanical signals was found using MR [correct classification rate (CCR) = 0.42] than LH (CCR = 0.38) to estimate human distal radius loading. Future applications of MR may enable clinicians to link subtle changes in bone strength to changes in day-to-day loading, identifying weak spots in the bone microstructure for local intervention and personalised treatment approaches.

Automated segmentation of fractured distal radii by 3D geodesic active contouring of in vivo HR-pQCT images

Radius fractures are among the most common fracture types; however, there is limited consensus on the standard of care. A better understanding of the fracture healing process could help to shape future treatment protocols and thus improve functional outcomes of patients. High-resolution peripheral quantitative computed tomography (HR-pQCT) allows monitoring and evaluation of the radius on the micro-structural level, which is crucial to our understanding of fracture healing. However, current radius fracture studies using HR-pQCT are limited by the lack of automated contouring routines, hence only including small number of patients due to the prohibitively time-consuming task of manually contouring HR-pQCT images. In the present study, a new method to automatically contour images of distal radius fractures based on 3D morphological geodesic active contours (3D-GAC) is presented. Contours of 60 HR-pQCT images of fractured and conservatively treated radii spanning the healing process up to one year post-fracture are compared to the current gold standard, hand-drawn 2D contours, to assess the accuracy of the algorithm. Furthermore, robustness was established by applying the algorithm to HR-pQCT images of intact radii of 73 patients and comparing the resulting morphometric indices to the gold standard patient evaluation including a threshold- and dilation-based contouring approach. Reproducibility was evaluated using repeat scans of intact radii of 19 patients. The new 3D-GAC approach offers contours within inter-operator variability for images of fractured distal radii (mean Dice score of 0.992 ± 0.005 versus median operator Dice score of 0.992 ± 0.006). The generated contours for images of intact radii yielded morphometric indices within the in vivo reproducibility limits compared to the current gold standard. Additionally, the 3D-GAC approach shows an improved robustness against failure (n = 5) when dealing with cortical interruptions, fracture fragments, etc. compared with the automatic, default manufacturer pipeline (n = 40). Using the 3D-GAC approach assures consistent results, while reducing the need for time-consuming hand-contouring.

Geriatric fracture centre vs usual care after proximal femur fracture in older patients: what are the benefits? Results of a large international prospective multicentre study

OBJECTIVE

The aim of this study was to determine the effect of treatment in geriatric fracture centres (GFC) on the incidence of major adverse events (MAEs) in patients with hip fractures compared with usual care centres (UCC). Secondary objectives included hospital-workflow and mobility-related outcomes.

DESIGN

Cohort study recruiting patients between June 2015 and January 2017. Follow-up was 1 year.

SETTING

International (six countries, three continents) multicentre study.

PARTICIPANTS

281 patients aged ≥70 with operatively treated proximal femur fractures.

INTERVENTIONS

Treatment in UCCs (n=139) or GFCs (n=142), that is, interdisciplinary treatment including regular geriatric consultation and daily physiotherapy.

OUTCOME MEASURES

Primary outcome was occurrence of prespecified MAEs, including delirium. Secondary outcomes included any other adverse events, time to surgery, time in acute ward, 1-year mortality, mobility, and quality of life.

RESULTS

Patients treated in GFCs (n=142) had a mean age of 81.9 (SD, 6.6) years versus 83.9 (SD 6.9) years in patients (n=139) treated in UCCs (p=0.013) and a higher mean Charlson Comorbidity Index of 2.0 (SD, 2.1) versus 1.2 (SD, 1.5) in UCCs (p=0.001). More patients in GFCs (28.2%) experienced an MAE during the first year after surgery compared with UCCs (7.9%) with an OR of 4.56 (95% CI 2.23 to 9.34, p<0.001). Analysing individual MAEs, this was significant for pneumonia (GFC: 9.2%; UCC: 2.9%; OR, 3.40 (95% CI 1.08 to 10.70), p=0.027) and delirium (GFC: 11.3%; UCC: 2.2%, OR, 5.76 (95% CI 1.64 to 20.23), p=0.002).

CONCLUSIONS

Contrary to our study hypothesis, the rate of MAEs was higher in GFCs than in UCCs. Delirium was revealed as a main contributor. Most likely, this was based on improved detection rather than a truly elevated incidence, which we interpret as positive effect of geriatric comanagement.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT02297581.

Formation Dominates Resorption With Increasing Mineralized Density and Time Postfracture in Cortical but Not Trabecular Bone: A Longitudinal HRpQCT Imaging Study in the Distal Radius

Clinical evaluation of fracture healing is often limited to an assessment of fracture bridging from radiographic images, without consideration for other aspects of bone quality. However, recent advances in HRpQCT offer methods to accurately monitor microstructural bone remodeling throughout the healing process. In this study, local bone formation and resorption were investigated during the first year post fracture in both the fractured (n = 22) and contralateral (n = 19) radii of 34 conservatively treated patients (24 female, 10 male) who presented with a unilateral radius fracture at the Innsbruck University Hospital, Austria. HRpQCT images and clinical metrics were acquired at six time points for each patient. The standard HRpQCT image acquisition was captured for all radii, with additional distal and proximal image acquisitions for the fractured radii. Measured radial bone densities were isolated with a voxel‐based mask and images were rigidly registered to images from the previous imaging session using a pyramid‐based approach. From the registered images, bone formation and resorption volume fractions were quantified for multiple density‐based thresholds and compared between the fractured and contralateral radius and relative to demographics, bone morphometrics, and fracture metrics using regression. Compared with the contralateral radius, both bone formation and resorption were significantly increased in the fractured radius throughout the study for nearly all evaluated thresholds. Higher density cortical bone formation continually increased throughout the duration of the study and was significantly greater than resorption during late‐stage healing in both the fractured and intact regions of the radius. With the small and diverse study population, only weak relationships between fracture remodeling and patient‐specific parameters were unveiled. However this study provides methods for the analysis of local bone remodeling during fracture healing and highlights relevant considerations for future studies, specifically that remodeling postfracture is likely to continue beyond 12‐months postfracture. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Development of axial compression and combined axial compression and torque loading configurations to reproduce strain in the implanted femur during activities of daily living

Femoral strain is indicative of the potential for bone remodeling (strain energy density, SED) and periprosthetic femoral fracture (magnitude of principal strains) after total hip arthroplasty (THA). Previous modeling studies have evaluated femoral strains in THA-implanted femurs under gait loads including both physiological hip contact force and femoral muscle forces. However, experimental replication of the complex muscle forces during activities of daily living (ADLs) is difficult for in vitro assessment of femoral implant or fixation hardware. Alternatively, cadaveric tests using simplified loading configurations have been developed to assess post-THA bone mechanics, although no current studies have demonstrated simplified loading configurations used in mechanical tests may simulate the physiological femoral strains under ADL loads. Using an optimization approach integrated with finite element analysis, this study developed axial compression and combined axial compression and torque testing configurations for three common ADLs (gait, stair-descent and sit-to-stand) via matching the SED profile of the femur in THA-implanted models of three specimens. The optimized simplified-loading models showed good agreement in predicting bone remodeling stimuli (post-THA change in SED per unit mass) and fatigue regions as compared with the ADL-loading models, as well as other modeling and clinical studies. The optimized simplified test configurations can provide a physiological-loading based pre-clinical platform for the evaluation of implant/fixation devices of the femur.

The AO trauma CPP bone infection registry: Epidemiology and outcomes of Staphylococcus aureus bone infection

Bone infection represents a serious complication of orthopedic surgery and Staphylococcus aureus is the most common pathogen. To improve the understanding of host-pathogen interaction, we developed a biospecimen registry (AO Trauma CPP Bone Infection Registry) to collect clinical data, bacterial isolates, and serum from patients with S. aureus bone infection. A prospective multinational registry with a 12-month follow-up was created to include adult patients (18 years or older) with culture-confirmed S. aureus infection in long bones after fracture fixation or arthroplasty. Baseline patient attributes and details on infections and treatments were recorded. Blood and serum samples were obtained at baseline, 6, and 12 months. Patient-reported outcomes were collected at 1, 6, and 12 months. Clinical outcomes were recorded. Two hundred and ninety-two patients with fracture-related infection (n = 157, 53.8%), prosthetic joint infection (n = 86, 29.5%), and osteomyelitis (n = 49, 16.8%) were enrolled. Methicillin-resistant S. aureus was detected in 82 patients (28.4%), with the highest proportion found among patients from North American sites (n = 39, 48.8%) and the lowest from Central European sites (n = 18, 12.2%). Patient outcomes improved at 6 and 12 months in comparison to baseline. The SF-36 physical component summary mean (95% confidence interval) score, however, did not reach 50 at 12 months. The cure rate at the end of the study period was 62.1%. Although patients improved with treatment, less than two-thirds were cured in 1 year. At 12-month follow-up, patient-reported outcome scores were worse for patients with methicillin-resistant S. aureus infections.

Relationship between tendon structure, stiffness, gait patterns and patient reported outcomes during the early stages of recovery after an Achilles tendon rupture

After an Achilles tendon (AT) injury, the decision to return to full weightbearing for the practice of sports or strenuous activities is based on clinical features only. In this study, tendon stiffness and foot plantar pressure, as objective quantitative measures that could potentially inform clinical decision making, were repeatedly measured in 15 patients until 3 months after the AT rupture by using shear wave elastography (SWE) and wearable insoles, respectively. Meanwhile, patient reported outcomes assessing the impact on physical activity were evaluated using the Achilles Tendon Total Rupture Score (ATRS). At week-2 post-injury, stiffness of the injured tendon varied from 6.00 ± 1.62 m/s (mean ± SD) close to the rupture to 8.91 ± 2.29 m/s when measured more distally. While near complete recovery was observed in distal and middle regions at week-8, the shear wave velocity in the proximal region recovered to only 65% of the contralateral value at week-12. In a parallel pre-clinical study, the tendon stiffness measured in vivo by SWE in a rat model was found to be strongly correlated with ex vivo values of the Young’s modulus, which attests to the adequacy of SWE for these measures. The insole derived assessment of the plantar pressure distribution during walking showed slight sub-optimal function of the affected foot at week-12, while the ATRS score recovered to a level of 59 ± 16. Significant correlations found between tendon stiffness, insole variables and distinct ATRS activities, suggest clinical relevance of tendon stiffness and foot plantar pressure measurements. These results illustrate how an alteration of the AT structure can impact daily activities of affected patients and show how digital biomarkers can track recovery in function over time.

Effect of Vitamin D Supplementation, Omega-3 Fatty Acid Supplementation, or a Strength-Training Exercise Program on Clinical Outcomes in Older Adults: The DO-HEALTH Randomized Clinical Trial

Importance

The benefits of vitamin D, omega-3 fatty acids, and exercise in disease prevention remain unclear.

Objective

To test whether vitamin D, omega-3s, and a strength-training exercise program, alone or in combination, improved 6 health outcomes among older adults.

Design, Setting, and Participants

Double-blind, placebo-controlled, 2 × 2 × 2 factorial randomized clinical trial among 2157 adults aged 70 years or older who had no major health events in the 5 years prior to enrollment and had sufficient mobility and good cognitive status. Patients were recruited between December 2012 and November 2014, and final follow-up was in November 2017.

Interventions

Participants were randomized to 3 years of intervention in 1 of the following 8 groups: 2000 IU/d of vitamin D3, 1 g/d of omega-3s, and a strength-training exercise program (n = 264); vitamin D3 and omega-3s (n = 265); vitamin D3 and exercise (n = 275); vitamin D3 alone (n = 272); omega-3s and exercise (n = 275); omega-3s alone (n = 269); exercise alone (n = 267); or placebo (n = 270).

Main Outcomes and Measures

The 6 primary outcomes were change in systolic and diastolic blood pressure (BP), Short Physical Performance Battery (SPPB), Montreal Cognitive Assessment (MoCA), and incidence rates (IRs) of nonvertebral fractures and infections over 3 years. Based on multiple comparisons of 6 primary end points, 99% confidence intervals are presented and P < .01 was required for statistical significance.

Results

Among 2157 randomized participants (mean age, 74.9 years; 61.7% women), 1900 (88%) completed the study. Median follow-up was 2.99 years. Overall, there were no statistically significant benefits of any intervention individually or in combination for the 6 end points at 3 years. For instance, the differences in mean change in systolic BP with vitamin D vs no vitamin D and with omega-3s vs no omega-3s were both -0.8 (99% CI, -2.1 to 0.5) mm Hg, with P < .13 and P < .11, respectively; the difference in mean change in diastolic BP with omega-3s vs no omega-3s was -0.5 (99% CI, -1.2 to 0.2) mm Hg; P = .06); and the difference in mean change in IR of infections with omega-3s vs no omega-3s was -0.13 (99% CI, -0.23 to -0.03), with an IR ratio of 0.89 (99% CI, 0.78-1.01; P = .02). No effects were found on the outcomes of SPPB, MoCA, and incidence of nonvertebral fractures). A total of 25 deaths were reported, with similar numbers in all treatment groups.

Conclusions and Relevance

Among adults without major comorbidities aged 70 years or older, treatment with vitamin D3, omega-3s, or a strength-training exercise program did not result in statistically significant differences in improvement in systolic or diastolic blood pressure, nonvertebral fractures, physical performance, infection rates, or cognitive function. These findings do not support the effectiveness of these 3 interventions for these clinical outcomes.

Trial Registration

ClinicalTrials.gov Identifier: NCT01745263.

Biomechanical comparison of fixation techniques for transverse acetabular fractures - Single-leg stance vs. sit-to-stand loading

OBJECTIVES

To biomechanically compare five different fixation techniques for transverse acetabular fractures using both the single-leg stance (SLS) and the sit-to-stand (STS) loading protocols and to directly compare fracture gap motion (FGM) and relative interfragmentary rotation (RIFR).

METHODS

Transtectal transverse acetabular fractures were created on fourth-generation composite hemipelves in a reproducible manner. Five different fixation techniques were biomechanically assessed using both an SLS and STS loading protocol: anterior plate (AP) only, posterior plate (PP) only, anterior plate plus posterior column screw (AP+PCS), posterior plate plus anterior column screw (PP+ACS) and anterior plus posterior plate (AP+PP). After preconditioning, the specimens were loaded from 50 to 750 N with a ramp of 100 N/s. FGM and RIFR under loads of 750 N were measured using an optical 3D measurement system.

RESULTS

In the three groups of fixation techniques addressing both columns, STS loading resulted in higher mean FGM and in RIFR than SLS loading. No construct failure was observed. In the single plate groups (AP only and PP only), STS loading resulted in failure of all specimens before reaching loads of 750 N, while no failure occurred after SLS loading. No significant differences in FGM and RIFR were found between the double plate (AP+PP) and the single plate plus column screw (AP+PCS and PP+ACS) techniques.

CONCLUSION

SLS loading appeared to overestimate the strength of acetabular fracture fixation constructs and STS loading may be more appropriate to provide clinically relevant biomechanical data. Internal fixation of a single column might not provide adequate stability for transverse fractures, while strength of single plate plus column screw fixation and double plate fixation was comparable.

The variance of clavicular surface morphology is predictable: an analysis of dependent and independent metadata variables

Background

The anatomy of the clavicle is specific and varied in reference to its topography and shape. These anatomic characteristics play an important role in the open treatment of clavicle fractures. The complex and variable topography creates challenges for implant placement, contouring, and position. Hardware prominence and irritation does influence the decision for secondary surgical intervention.

Methods

Computerized tomographic scans of 350 adult clavicles with the corresponding patients' metadata were acquired and digitized. Morphologic parameters determining the shape of the clavicle were defined and computed for each digitized bone. The extracted morphologic parameters were correlated with patient metadata to analyze the relationship between morphologic variability and patient characteristics.

Results

The morphologic parameters defining the shape, that is, the radius of the medial and lateral curves, the apparent clavicle height and width, and the clavicle bow position, correlate with the clavicle length. The clavicle length correlates with the patients' height. Gender differences in shape and form were dependent and related to individual height distribution and clavicle length. Asian populations showed a similarly predictable, but shifted, correlation between shape and clavicle length.

Conclusion

This anatomic analysis shows that the clavicle shape can be predicted through the clavicle length and patients' stature. Smaller patients have shorter and more curved clavicles, whereas taller patients have longer and less curved clavicles. This correlation will aid surgeons in fracture reduction, implant curvature selection, and in optimal adaptation of clavicle implants, and represents the basis for anatomically accurate solutions for clavicle osteosynthesis.

DO-HEALTH: Vitamin D3 - Omega-3 - Home exercise - Healthy aging and longevity trial - Design of a multinational clinical trial on healthy aging among European seniors

DO-HEALTH is a multi-center clinical trial among 2157 community-dwelling European men and women age 70 and older. The 2x2x2 randomized-control factorial design trial tested the individual and additive benefit, as well as the cost-effectiveness, of 3 interventions: vitamin D 2000 IU/day, omega-3 fatty acids 1000 mg/day (EPA + DHA, ratio 1:2), and a 30-minute 3 times/week home exercise (strength versus flexibility). Each treatment tested has shown considerable prior promise from mechanistic studies, small clinical trials, or large cohort studies, in the prevention of common age-related chronic diseases, but definitive data are missing. DO-HEALTH will test these interventions in relation to 6 primary endpoints (systolic and diastolic blood pressure, non-vertebral fractures, Short Physical Performance Battery score, the Montreal Cognitive Assessment, and risk of infections), plus several secondary endpoints explored in ancillary studies (i.e. rate of any falls and injurious falls, joint pain, oral health, quality of life, and incident frailty). As the 3 interventions have distinct mechanisms of action for each of the 6 primary endpoints, a maximum benefit is expected for their additive benefit as a "multi-modal" intervention. The trial duration is 3 years with in-person contacts with all participants at 4 clinical visits and by quarterly phone calls. Baseline and follow-up blood samples were collected in all participants to measure changes in 25-hydroxyvitamin D and poly-unsaturated fatty acid concentrations. Our objective was to test interventions that are expected to promote healthy aging and longer life expectancy and that can be easily and safely implemented by older community-dwelling adults.

Multidisciplinary inpatient rehabilitation improves the long-term functional status of geriatric hip-fracture patients

BACKGROUND

As the world population ages, the number of hip-related fractures in the elderly is steadily increasing. These fractures generate a major worldwide healthcare problem and frequently lead to deterioration of life quality, mobility and independence in activity of daily life of geriatric patients. At present, many studies have investigated and proved benefits of multidisciplinary orthogeriatric care for elderly hip-fracture patients. Only few studies however, have analyzed treatment concepts for those patients directly following discharge from hospital in specialized rehabilitation centers. The aim of this study was to evaluate effects of a multidisciplinary inpatient rehabilitation on the short- and long-term functional status of geriatric patients who suffered from hip fracture.

METHODS

A total of 161 hip-fracture patients aged 80 years and above, or additionally 70 years and above suffering from age-typical multimorbidity were included in this study. Patients who had an initial Barthel Index lower than 30 points were excluded from this study, as most of these patients were not able to attend a therapy at the rehabilitation center due to a poor functional status. The patients were separated into two subgroups dependent on the availability of treatment spots at the rehabilitation center. No other item was used to discriminate between the groups. Group A (n = 95) stayed an average of 21 days at an inpatient rehabilitation center that specialized in geriatric patients. Group B (n = 66) underwent the standard postoperative treatment and were sent home with further treatment by their general practitioner, nursing staff and physiotherapists. To evaluate the patients' functional status over the course of time we used the Barthel Index, which was evaluated for every patient on the day of discharge, as well as during checkups after 3, 6 and 12 months.

RESULTS

The average Barthel Index at the day of discharge was 57.79 ± 14.92 points for Group A and 56.82 ± 18.76 points for Group B (p = 0.431). After 3 months, the average Barthel Index was 82.43 points for Group A and 73.11 points for group B (p = 0.005). In the 6-month checkup Group A's average Barthel Index was 83.95 points and Group B's was 74.02 points (p = 0.002). After 12 months, patients from Group A had an average Barthel Index of 81.21 while patients from Group B had an average Barthel Index of 69.85 (p = 0.005).

CONCLUSION

The results of this study reveal a significantly better outcome concerning both, short-term and long-term functional status after 3, 6 and 12 months for geriatric hip-fracture patients, who underwent an inpatient treatment in a rehabilitation center following the initial therapy.

Quantifying Functional Difference in Centre of Pressure Post Achilles Tendon Rupture using Sensor Insoles

Significant advances are being made to instrument and more objectively quantify gait and mobility assessment, treatment and rehabilitation. Wearable, inertial, optical and location-based technologies are proposed as scalable soutions, suited to both clinic and home-based settings, that can provide clinically meaningful insights into gait and mobility. In this paper, sensorised insoles are shown to provide the means to measure where pressure is distributed through each foot for each step, while it is in contact with the ground. Through profiling the points through which pressure is applied over each step and comparing changes between the affected and healthy limbs, insights into biomechanical foot dysfunction are shown for a patient population which may inform assessment, treatment and rehabilitation. This paper proposes a series of sensor-agnostic metrics derived from sensorised insoles to quantify foot mobility over a series of steps in a patient population. Differences in these metrics are shown between the affected and unaffected foot in a cohort of patients 8 weeks post Achilles tendon rupture.

Suprapatellar nailing of fractures of the tibia

OBJECTIVE

Intramedullary nailing of tibia fractures via a suprapatellar, transarticular approach with the knee joint in 20-30° of flexion and the use of specific protection tubes to preserve intra-articular structures.

INDICATIONS

Extra-articular fractures of the proximal tibia; simple and comminuted fractures of the tibia diaphysis; segmental diaphyseal fractures of the tibia; extra-articular fractures of the distal tibia and fractures with simple intra-articular distal extension; floating knee injuries.

CONTRAINDICATIONS

Gustilo grade 3C open fractures of the tibia; severe soft tissue laceration, contamination or infection in the suprapatellar area; ipsilateral knee joint prosthesis; knee arthrodesis; implants blocking the nail entry point.

SURGICAL TECHNIQUE

Via a suprapatellar, transarticular approach an intramedullary tibia nail is inserted after anatomical reposition of the tibial fracture with the knee joint in 20-30° of flexion. Use of specific protection tubes to preserve intra-articular structures. The proximal and distal locking configuration depends upon the specific fracture characteristics.

RESULTS

In all, 61 patients underwent suprapatellar tibia nailing and were under follow-up at least until fracture union. Twelve patients suffered from an open fracture. A total of 17 patients had a distal third fracture, 8 sustained a proximal third fracture and 36 had a shaft fracture. Follow-up focused on patients with distal fractures; 6/17 patients sustained open fractures. Average time to union was 9 weeks. One fracture did not heal and required exchange nailing. Two patients complained about anterior knee pain. Functionally, full range of motion was regained in all patients.

Non-operative management of blunt hepatic and splenic injury: a time-trend and outcome analysis over a period of 17 years

Background

A widespread shift to non-operative management (NOM) for blunt hepatic and splenic injuries has been observed in most centers worldwide. Furthermore, many countries introduced safety measures to systematically reduce severe traffic and leisure sports injuries. This study aims to evaluate the effect of these nationwide implementations on individual patient characteristics and outcomes through a time-trend analysis over 17 years in an Austrian high-volume trauma center.

Methods

A retrospective review of all emergency trauma patients admitted to the Medical University of Innsbruck from 2000 to 2016. Injury severity, clinical data on admission, operative and non-operative treatment parameters, complications, and in-hospital mortality were evaluated.

Results

In total, 731 patients were treated with blunt hepatic and/or splenic injuries. Among these, 368 had a liver injury, 280 splenic injury, and 83 combined hepatic/splenic injury. Initial NOM was performed in 82.6% of all patients (93.5% in hepatic and 71.8% in splenic injuries) with a success rate of 96.7%. The secondary failure rate of NOM was 3.3% and remained consistent over 17 years (p = 0.515). In terms of injury severity, we observed a reduction over time, resulting in an overall mortality rate of 4.8% and 3.5% in the NOM group (decreasing from 7.5 to 1.9% and from 5.6 to 1.3%, respectively). These outcomes confirmed an improved utilization of the NOM approach.

Conclusion

Our cohort represents one of the largest Central European single-center experiences available in the literature. NOM is the standard of care for blunt hepatic and splenic injuries and successful in > 96% of all patients. This rate was quite constant over 17 years (p = 0.515). Overall, national and regional safety measures resulted in a significantly decreased severity of observed injury patterns and deaths due to blunt hepatic or splenic trauma. Although surgery is nowadays only applied in about one third of splenic injury patients in our center, these numbers might further decrease by intensified application of interventional radiology and modern coagulation management.

Electronic supplementary material

The online version of this article (10.1186/s13017-019-0249-y) contains supplementary material, which is available to authorized users.

High percentage of microbial colonization of osteosynthesis material in clinically unremarkable patients

Stabilization of fractures with internal fixation devices is a common procedure and implant‐associated infections are a dreaded complication. The exact pathomechanism is not completely understood; however, microbial colonization of osteosynthesis material is considered a trigger for infection. This study aimed to determine the colonization rate of osteosynthesis implants in patients with no clinical or laboratory signs of infection, using two methods, conventional culture and polymerase chain reaction (PCR) of sonication fluid. Fifty‐seven patients aged between 18 and 79 years without signs of infection who underwent routine removal of osteosynthesis devices between March 2015 and May 2017 were included in this study. Osteosynthesis material was investigated by sonication followed by cultivation of the sonication fluid in blood culture bottles and PCR analysis, simultaneously. Additionally, electron scanning microscopy was performed in nine representative implants to evaluate biofilm production. Thirty‐two (56.1%) implants showed a positive result either by culture or PCR with coagulase‐negative staphylococci being the most commonly identified microorganism (68.1%). Furthermore, the detection rate of the culture (50.9%) was significantly higher compared to PCR (21.1%). The scanning electron microscopy imaging demonstrated biofilm‐like structures in four of six culture and/or PCR‐positive samples. This study is the first, to the best of our knowledge, to demonstrate bacterial colonization of osteosynthesis implants in healthy patients with no clinical or laboratory signs of infection. Colonization rate was unexpectedly high and conventional culture was superior to PCR in microbial detection. The common understanding that colonization is a trigger for infection underlines the need for strategies to prevent colonization of implant material like antibiotic‐loaded coating or intraoperative gel application.

Coupling Single Photons from Discrete Quantum Emitters in WSe2 to Lithographically Defined Plasmonic Slot Waveguides

We report the observation of the generation and routing of single plasmons generated by localized excitons in a WSe₂ monolayer flake exfoliated onto lithographically defined Au-plasmonic waveguides. Statistical analysis of the position of different quantum emitters shows that they are (3.3 ± 0.7) times more likely to form close to the edges of the plasmonic waveguides. By characterizing individual emitters, we confirm their single-photon character via the observation of antibunching in the signal ( g⁽²⁾(0) = 0.42) and demonstrate that specific emitters couple to modes of the proximal plasmonic waveguide. Time-resolved measurements performed on emitters close to and far away from the plasmonic nanostructures indicate that Purcell factors up to 15 ± 3 occur, depending on the precise location of the quantum emitter relative to the tightly confined plasmonic mode. Measurement of the point spread function of five quantum emitters relative to the waveguide with <50 nm precision is compared with numerical simulations to demonstrate the potential for greater increases in the coupling efficiency for ideally positioned emitters. The integration of such strain-induced quantum emitters with deterministic plasmonic routing is a step toward deep-subwavelength on-chip single quantum light sources.

Screw tip augmentation leads to improved primary stability in the minimally invasive treatment of displaced intra-articular fractures of the calcaneus: a biomechanical study

PURPOSE

To investigate if the stability of minimally invasive screw osteosynthesis of displaced intra-articular calcaneal fractures (DIACF) can be effectively increased by an innovative approach to screw tip augmentation.

METHODS

In eight-paired human cadaver hindfoot specimens, DIACF of Sanders type IIB were treated with either standard screw osteosynthesis or with bone cement augmentation of the screw tips in the main fragments. The instrumented specimens were subjected to a cyclic loading protocol (9000 cycles, with stepwise increasing loads, 100-1000 N). The interfragment motions were quantified as tuber fragment tilt (TFT) and posterior facet inclination angle (PFIA) using a 3-D motion analysis system. Böhler's angle (BA) was evaluated from X-rays. A load-to-failure test was performed after the cyclic loading protocol.

RESULTS

All but one specimen of the augmented group withstood more cycles than the respective specimens of the non-augmented group. Mean cycles to failure for the failure criterion of 5° TFT were 7299 ± 1876 vs. 3864 ± 1810, corresponding to loads of 811 N ± 195 vs. 481 N ± 180, (P = 0.043). There were no significant differences observed in the PFIAs. The failure criterion of 5° BA was reached after a mean of 7929 cycles ± 2004 in the augmented group and 4129 cycles ± 2178 in the non-augmented group, corresponding to loads of 893 N ± 200 vs. 513 N ± 218, (P = 0,090). The mean load-to-failure of the four specimens in the augmented group that completed the cyclic loading was 1969 N over a 1742-2483 N range.

CONCLUSION

Screw tip augmentation significantly improved the mechanical stability of the calcanei after osteosynthesis in terms of decreased tuber fragment tilts and less changes in Böhler's angle.

Cement augmentation of the Proximal Femoral Nail Antirotation (PFNA) - A multicentre randomized controlled trial

INTRODUCTION

New implant designs like the Proximal Femoral Nail Antirotation (PFNA) were developed to reduce failure rates in unstable pertrochanteric fractures in the elderly. Standardized implant augmentation with up to 6 mL of polymethylmethacrylate (PMMA) cement has been introduced to enhance implant anchorage by increasing the implant-bone interface in osteoporotic bone conditions. Biomechanically, loads to failure were significantly higher with augmentation. The primary objective of this study was to compare the mobility of patients with closed unstable trochanteric fractures treated by PFNA either with or without cement augmentation.

PATIENTS AND METHODS

A prospective multicentre, randomized, patient-blinded trial was conducted with ambulatory patients aged 75 or older who sustained a closed, unstable trochanteric fracture. Surgical fixation had to be performed within 72 h after admission. Outcomes were evaluated at baseline, during surgery, 3 to 14 days after surgery, 3 months, 6 months, and 12 months after surgery. To evaluate the primary objective, patients' walking speed was assessed by the Timed Up and Go (TUG) test. Secondary objectives included the analysis of implant migration assessed on radiographs, quality of life measured by the Barthel Index, mobility measured by the Parker Mobility Score, and complications.

RESULTS

Of 253 randomized patients, 223 patients were eligible: 105 patients were allocated to the PFNA Augmentation group and 118 to PFNA group. At 3 to 14 days after surgery, there was no statistical significant difference in mean walking speed between the treatment groups. For the secondary objectives, also no statistical significant differences were found. However, no patient in the PFNA Augmentation group had a reoperation due to mechanical failure or symptomatic implant migration compared to 6 patients in the PFNA group.

CONCLUSIONS

Augmentation of the PFNA blade did not improve patients' walking ability compared to the use of a non-augmented PFNA but might have the potential to prevent reoperations by strengthening the osteosynthesis construct.

Optimizing intraoperative imaging during proximal femoral fracture fixation - a performance improvement program for surgeons

INTRODUCTION

Formal training for surgeons regarding intraoperative imaging is lacking. This project investigated the effect of an educational intervention focusing on obtaining and assessing a standardized lateral view of the proximal femur during intramedullary nailing of a pertrochanteric fracture.

MATERIALS AND METHODS

Anatomical landmarks of the proximal femur that can be identified using intraoperative fluoroscopy and criteria for image quality, i.e. quality of projection were defined in a consensus process, followed by the development of educational materials and a 7-item checklist. Five surgeons from 5 Trauma Centers in 4 countries participated. Each surgeon a) assessed 5 of their own retrospective cases and 5 retrospective cases from 4 colleagues from their clinic, b) viewed an educational video and poster and re-assessed the same cases, and c) assessed the intraoperative images of 5 prospectively collected consecutive cases of their own and of colleagues afterwards.

RESULTS

The percentage of positive ratings for image quality increased from 72% prior to educational intervention to 88% after intervention (p<0.001), and number of "not assessable" images decreased significantly. Percentage agreement between surgeons on the assessments increased from 75% to 87%. The proportion of best possible ratings for fracture reduction and implant position increased from 58% to 72% and from 49% to 66%, respectively. Percentage agreement between surgeons on assessment of reduction and implant position increased.

DISCUSSION AND CONCLUSIONS

A focused educational intervention can improve surgeons' ability to obtain and assess lateral view intraoperative images of the proximal femur and can improve the quality of reduction and implant positioning.

Quality of fracture reduction assessed by radiological parameters and its influence on functional results in patients with pilon fractures-A prospective multicentre study

INTRODUCTION

The management of pilon fractures remains a challenging issue. Due to the complexity of factors that influence the outcome, it has been questioned if anatomical reductions of articular fracture are relevant. The lack of a commonly accepted assessment of quality of fracture reduction compounded the uncertainty of the importance of anatomical reduction in pilon fracture. The current study aimed to define parameters that can better assess the reduction quality and to investigate the influence of reduction quality on functional outcomes.

METHODS

Patients with unilateral pilon fracture of the AO/OTA type 43-B or 43-C were consecutively recruited to the study and followed up for 2 years after surgery. Postoperative radiographs of the injured and the contralateral joints were evaluated and 13 radiological parameters measured by 2 independent surgeons. The reliability of the measurements for each parameter was assessed by the Intraclass Correlation Coefficient (ICC), and 4 parameters with the highest ICC scores were deemed most reliable and were selected for further analyses. Functional outcome was assessed by the Foot and Ankle Ability Measure (FAAM) for daily living and sports activities. The 4 most reliable radiologic parameters, together with 3 possible baseline confounders (age, AO/OTA fracture type, and open versus closed injury), were analysed using both univariable and multivariable analysis for their association with the FAAM scores. Secondary outcome measures including pain, ankle range of motion (ROM), quality of life (QoL), and adverse events were also reported.

RESULTS

The length of lateral malleolus (LLM), anterior distal tibia angle, anterior talar shift, and length of medial malleolus scored highest on reliability in ICC assessment (ICC=0.76, 0.72, 0.58, and 0.45, respectively). Only LLM exhibited statistical significant association with the 2-year FAAM results. At the 2-year follow-up, the injured joints on average achieved a ROM of 70.7% (95% CI=63.9-77.6) when compared to the contralateral joints, and patients did not regain the pre-injury QoL overall.

CONCLUSION

The multivariable analysis showed that LLM (independent of age, AO/OTA fracture type, and open/closed injury) was a reliable indicator of reduction quality and a prognostic factor for patient outcome in pilon fracture surgery.

A few-emitter solid-state multi-exciton laser

We report on non-conventional lasing in a photonic-crystal nanocavity that operates with only four solid-state quantum-dot emitters. In a comparison between microscopic theory and experiment, we demonstrate that irrespective of emitter detuning, lasing with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${g}^{\mathrm{(2)}}=1$$\end{document}g(2)=1 is facilitated by means of emission from dense-lying multi-exciton states. In the spontaneous-emission regime we find signatures for radiative coupling between the quantum dots. The realization of different multi-exciton states at different excitation powers and the presence of electronic inter-emitter correlations are reflected in a pump-rate dependence of the β-factor.

Evaluation of the geriatric co-management for patients with fragility fractures of the proximal femur (Geriatric Fracture Centre (GFC) concept): protocol for a prospective multicentre cohort study

INTRODUCTION

Treatment of fractures in the elderly population is a clinical challenge due partly to the presence of comorbidities. In a Geriatric Fracture Centre (GFC), patients are co-managed by a geriatrician in an attempt to improve clinical outcomes and reduce morbidity and mortality. Until now the beneficial effect of orthogeriatric co-management has not been definitively proven. The primary objective of this study is to determine the effect of GFC on predefined major adverse events related to a hip fracture compared to usual care centres (UCC). The secondary objectives include assessments in quality of life, patient-reported outcomes and cost-effectiveness.

METHODS AND ANALYSIS

Two hundred and sixty-six elderly patients diagnosedwith hip fracture and planned to be treated with osteosynthesis or endoprosthesis in either a GFC or UCC study site will be recruited, 133 per type of centre. All procedures and management will be done according to the site's standard of care. Study-related visits will be performed at the following time points: preoperative, intraoperative, discharge from the orthopaedic/trauma department, discharge to definite residential status, 12 weeks and 12 months postsurgery. Data collected include demographics, residential status, adverse events, patient-reported outcomes, fall history, costs and resources related to treatment. The risk of major adverse events at 12 months will be calculated for each centre type; patient-reported outcomes will be analysed by mixed effects regression models to estimate differences in mean scores between baseline and follow-ups whereas cost-effectiveness will be assessed using the incremental cost-effectiveness ratio.

ETHICS AND DISSEMINATION

Ethics approval for this study was granted from the local Ethics Committees or Institutional Review Board from each of the participating sites prior to patient enrolment. The results of this study will be published in peer-reviewed journals and presented at different conferences.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT02297581; pre-results.

Improving site selection in clinical studies: a standardised, objective, multistep method and first experience results

INTRODUCTION

A considerable number of clinical studies experience delays, which result in increased duration and costs. In multicentre studies, patient recruitment is among the leading causes of delays. Poor site selection can result in low recruitment and bad data quality. Site selection is therefore crucial for study quality and completion, but currently no specific guidelines are available.

MATERIAL AND METHODS

Selection of sites adequate to participate in a prospective multicentre cohort study was performed through an open call using a newly developed objective multistep approach. The method is based on use of a network, definition of objective criteria and a systematic screening process.

ILLUSTRATIVE EXAMPLE OF THE METHOD AT WORK

Out of 266 interested sites, 24 were shortlisted and finally 12 sites were selected to participate in the study. The steps in the process included an open call through a network, use of selection questionnaires tailored to the study, evaluation of responses using objective criteria and scripted telephone interviews. At each step, the number of candidate sites was quickly reduced leaving only the most promising candidates. Recruitment and quality of data went according to expectations in spite of the contracting problems faced with some sites.

CONCLUSION

The results of our first experience with a standardised and objective method of site selection are encouraging. The site selection method described here can serve as a guideline for other researchers performing multicentre studies.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT02297581.

Fast-resorbable antibiotic-loaded hydrogel coating to reduce post-surgical infection after internal osteosynthesis: a multicenter randomized controlled trial

BACKGROUND

Infection is one of the main reasons for failure of orthopedic implants. Antibacterial coatings may prevent bacterial adhesion and biofilm formation, according to various preclinical studies. The aim of the present study is to report the first clinical trial on an antibiotic-loaded fast-resorbable hydrogel coating (Defensive Antibacterial Coating, DAC®) to prevent surgical site infection, in patients undergoing internal osteosynthesis for closed fractures.

MATERIALS AND METHODS

In this multicenter randomized controlled prospective study, a total of 256 patients in five European orthopedic centers who were scheduled to receive osteosynthesis for a closed fracture, were randomly assigned to receive antibiotic-loaded DAC or to a control group (without coating). Pre- and postoperative assessment of laboratory tests, wound healing, clinical scores and X-rays were performed at fixed time intervals.

RESULTS

Overall, 253 patients were available with a mean follow-up of 18.1 ± 4.5 months (range 12-30). On average, wound healing, clinical scores, laboratory tests and radiographic findings did not show any significant difference between the two groups. Six surgical site infections (4.6%) were observed in the control group compared to none in the treated group (P < 0.03). No local or systemic side-effects related to the DAC hydrogel product were observed and no detectable interference with bone healing was noted.

CONCLUSIONS

The use of a fast-resorbable antibiotic-loaded hydrogel implant coating provides a reduced rate of post-surgical site infections after internal osteosynthesis for closed fractures, without any detectable adverse event or side-effects.

LEVEL OF EVIDENCE

2.

New approaches for cement-based prophylactic augmentation of the osteoporotic proximal femur provide enhanced reinforcement as predicted by non-linear finite element simulations

BACKGROUND

High incidence and increased mortality related to secondary, contralateral proximal femoral fractures may justify invasive prophylactic augmentation that reinforces the osteoporotic proximal femur to reduce fracture risk. Bone cement-based approaches (femoroplasty) may deliver the required strengthening effect; however, the significant variation in the results of previous studies calls for a systematic analysis and optimization of this method. Our hypothesis was that efficient generalized augmentation strategies can be identified via computational optimization.

METHODS

This study investigated, by means of finite element analysis, the effect of cement location and volume on the biomechanical properties of fifteen proximal femora in sideways fall. Novel cement cloud locations were developed using the principles of bone remodeling and compared to the "single central" location that was previously reported to be optimal.

FINDINGS

The new augmentation strategies provided significantly greater biomechanical benefits compared to the "single central" cement location. Augmenting with approximately 12ml of cement in the newly identified location achieved increases of 11% in stiffness, 64% in yield force, 156% in yield energy and 59% in maximum force, on average, compared to the non-augmented state. The weaker bones experienced a greater biomechanical benefit from augmentation than stronger bones. The effect of cement volume on the biomechanical properties was approximately linear. Results of the "single central" model showed good agreement with previous experimental studies.

INTERPRETATION

These findings indicate enhanced potential of cement-based prophylactic augmentation using the newly developed cementing strategy. Future studies should determine the required level of strengthening and confirm these numerical results experimentally.

Extracellular matrix mimicking scaffold promotes osteogenic stem cell differentiation: A new approach in osteoporosis research

BACKGROUND

Osteoporosis is a common metabolic disease, with mesenchymal stem cells discussed to play an important role in its pathomechanism. For in vitro osteoporosis studies, selection of adequate culture conditions is mandatory so as to preserve cell properties as far as possible. A suitable cell culture surface would ideally provide reproducible experimental conditions by resembling those in-vivo.

OBJECTIVE

Generating an improved growth surface for osteogenic differentiation of human bone marrow derived mesenchymal stem cells (hBMSCs).

METHODS

We modified electrospun gelatine meshes with hydroxyapatite nanopowder. The potential beneficial impact of the ensuing culture conditions were evaluated by cultivating and comparing the growth of cells from osteoporotic and non-osteoporotic donors on either hydroxyapatite-gelatine (HA) meshes, pure gelatine meshes, or 2D standard tissue culture surfaces.

RESULTS

After 21 days of differentiation, cells grown on pure or HA-gelatine meshes showed significantly higher mineralization levels compared to cells cultured in standard conditions. The amount of mineralization varied considerably in hBMSC cultures of individual patients but showed no significant difference between stem cells obtained from osteoporotic or non-osteoporotic donors.

CONCLUSIONS

Overall, these results indicate that the use of HA-gelatine meshes as growth surfaces may serve as a valuable tool for cultivation and differentiation of mesenchymal stem cells along the osteogenic lineage, facilitating future research on osteoporosis and related issues.

Expert Consensus on Predictive Parameters for the Occurrence of a Fall and a Contralateral Hip Fracture 1 and 3 Years After Hip Fracture: A Delphi Survey

Background:

Early identification of people at risk for a contralateral hip fracture would be desirable to favorably influence patients’ prognosis. A recent systematic review failed to depict stringent patterns of risk parameters to be used for decision-making in clinical practice.

Objective:

To perform a consensus study using the Delphi method to reach an expert consensus on predictive parameters for the occurrence of a fall and a contralateral hip fracture 1 and 3 years after hip fracture.

Methods:

A list of potential members of the expert panel was identified based on the authors’ list of a recently conducted systematic review. Participating experts were asked to name parameters determining the probability for a fall and a contralateral hip fracture 1 and 3 years after an occurred hip fracture, separately. Additionally, we asked how those stated parameters should be measured. All mentioned parameters were compiled and sent back to the experts asking them to weight each single parameter by assigning a number between 1 (not important) and 10 (very important). The survey was conducted online using the REDCap software package. We defined expert agreement if the interquartile range of attributed weights for a parameter was ≤2. A relevant parameter had at least a median weight of 8.

Results:

Twelve experts from 7 countries completed the survey. Presence of fall history and mental and general health status were considered relevant irrespective of the outcome. For falling within 1 and 3 years, the number of medications and residential status were considered relevant, while for fractures within 1 and 3 years, osteoporosis management was considered important.

Conclusion:

Using the insights gained in this consensus study, empiric studies need to be set up assessing the prognostic value of the selected parameters.

Do we still need autopsy in times of modern multislice computed tomography?-Missed diagnoses in the emergency room

INTRODUCTION

In spite of increasing quality of emergency room (ER) assessment in trauma patients and improved accuracy of modern multislice computed tomography (MSCT), the number of potentially missed diagnoses is still controversial. The aim of this study was to compare the initial findings of ER assessment and MSCT to the findings during autopsy in trauma patients not surviving the first 48 h after admission. We hypothesized that autopsy was more accurate than MSCT in diagnosing potentially fatal diagnoses.

PATIENTS AND METHODS

Between January 2004 and September 2007, all trauma patients undergoing ER treatment in our institution who deceased within 48 h after admission were analyzed regarding diagnoses from initial ER assessment, including MSCT, and diagnoses from autopsy. Data were prospectively collected and retrospectively analyzed. Autopsy reports were compared to diagnoses of ER assessment and MSCT. Missed diagnoses (MD) and missed potentially fatal diagnoses (MPFD) were analyzed.

RESULTS

Seventy-three patients with a mean age of 53.2 years were included into the study. Sixty-three percent were male. Autopsy revealed at least one missed diagnosis in 25% of the patients, with the thoracic area accounting for 67% of these. At least one MPFD was found in 4.1% of the patients, all of them being located in the thorax. Total numbers of MD and MPFD were significantly lower for the newer CT generation (64 MSCT, N = 11), compared to older one (4 MSCT, N = 26).

CONCLUSIONS

As determined by autopsy, modern multislice computed tomography is an accurate method to diagnose injuries. However, 25% of all diagnoses, and 4.1% of potentially fatal diagnoses are still missed in trauma patients, who deceased within the first 48 h after admission. Therefore, autopsy seems to be necessary to determine potentially missed diagnoses for both academic and medicolegal reasons as well as for quality control.

EULAR/EFORT recommendations for management of patients older than 50 years with a fragility fracture and prevention of subsequent fractures

The European League Against Rheumatism (EULAR) and the European Federation of National Associations of Orthopaedics and Traumatology (EFORT) have recognised the importance of optimal acute care for the patients aged 50 years and over with a recent fragility fracture and the prevention of subsequent fractures in high-risk patients, which can be facilitated by close collaboration between orthopaedic surgeons and rheumatologists or other metabolic bone experts. Therefore, the aim was to establish for the first time collaborative recommendations for these patients. According to the EULAR standard operating procedures for the elaboration and implementation of evidence-based recommendations, 7 rheumatologists, a geriatrician and 10 orthopaedic surgeons met twice under the leadership of 2 convenors, a senior advisor, a clinical epidemiologist and 3 research fellows. After defining the content and procedures of the task force, 10 research questions were formulated, a comprehensive and systematic literature search was performed and the results were presented to the entire committee. 10 recommendations were formulated based on evidence from the literature and after discussion and consensus building in the group. The recommendations included appropriate medical and surgical perioperative care, which requires, especially in the elderly, a multidisciplinary approach including orthogeriatric care. A coordinator should setup a process for the systematic investigations for future fracture risk in all elderly patients with a recent fracture. High-risk patients should have appropriate non-pharmacological and pharmacological treatment to decrease the risk of subsequent fracture.

[Augmentation techniques on the proximal femur]

BACKGROUND

Due to the demographic change fractures of the proximal femur are an increasing major healthcare problem and are associated with the highest mortality among frailty fractures.

OBJECTIVES

These mainly osteoporosis-associated fractures of the hip often represent a surgical challenge and the outcome has a decisive influence on the preservation of function and independency of orthogeriatric patients. Augmentation techniques could improve the stability of osteosynthesis in proximal femoral fractures.

METHODS

Cement augmentation of proximal femoral nailing (PFNA) for the treatment of pertrochanteric femoral fractures is the most commonly used and standardized method of augmentation for these fractures by which a safer condition for immediate full weight bearing and mobilization can be achieved.

RESULTS

In biomechanical and clinical studies good fracture healing was shown and there was no evidence of cement-associated complications in augmented PFNA nailing. In the majority of patients the mobility level prior to trauma could be achieved.

CONCLUSION

In addition to the optimal surgical treatment, secondary prevention such as osteoporosis management to avoid further fractures is crucial in the treatment of these patients. This article is based on the current literature and provides an overview of the possible applications of cement augmentation for the treatment of proximal femoral fractures. In addition the surgical approach as well as previous scientific data on an established osteosynthesis using cement-augmented PFNA for the treatment of pertrochanteric frailty fractures are presented.

Prophylactic augmentation of the osteoporotic proximal femur-mission impossible?

The high incidence of secondary hip fractures and the associated markedly increased mortality call for preventive actions that could help to avoid these injuries. By providing immediate strengthening and not relying on patient compliance, internal prophylactic augmentation of the osteoporotic proximal femur may overcome the main limitations of systemic bone drugs and wearable protective pads. However, such a method would have to provide sufficient and reliable strengthening effect with minimal risks and side effects to justify the need of an invasive treatment. The requirements for an internal reinforcement approach are thus strict and include mechanical, biological, clinical, ethical and financial criteria. Here we first attempt to describe the properties of an ideal augmentation method. Previously published methodologies and techniques developed at our research institute, including approaches using cements, metals, other materials or combined approaches, are then reviewed and evaluated according to these aspects. We conclude that none of the discussed methodologies appears to be able to deliver a sufficiently high gain-versus-risk ratio that could justify the clinical application and thus augmentation of the osteoporotic proximal femur remains a challenge. Finally, we provide suggestions for the development and evaluation of future strategies.

Bone Mass Distribution of the Distal Tibia in Normal, Osteopenic, and Osteoporotic Conditions: An Ex Vivo Assessment Using HR-pQCT, DXA, and Computational Modelling

Osteoporosis leads to bone loss and structural deterioration, which increase the risk of fractures. The aim of this study was to characterize the three-dimensional (3D) bone mass distributions of the distal tibia in normal, osteopenic, and osteoporotic conditions. High-resolution peripheral quantitative computed tomography (HR-pQCT) of the 33 % of the distal tibia and local dual-energy X-ray absorptiometry were applied to 53 intact, fresh-frozen tibiae. The HR-pQCTs were graded to assign local T-scores and merged into three equally sized average normal, osteopenic, and osteoporotic surface models. Volumetric bone mineral density (vBMD) was determined using categorized T-scores, volumetric visualization, and virtual bore probes at the dia-, meta-, and epiphyseal sites (T-DIA, T-META, and T-EPI). We observed a distinct 3D bone mass distribution that was gradually uninfluenced by T-score categories. T-DIA was characterized by the lowest bone mass located in the medullary cavity and a wide homogenous cortex containing the maximum vBMD. The T-META showed decreased cortical thickness and maximal vBMD. At the T-EPI, the relatively low vBMD of the mostly trabecular bone was similar to the maximal cortical vBMD in this sub-region. Four trabecular regions of low bone mass were identified in the recesses. The bone content gradually decreased at all sites, whereas the pattern of bone mass distribution remained essentially unchanged, with the exception of disproportionate losses at T-DIA, T-META, and T-EPI that consistently showed increased endocortical, intracortical, and trabecular bone loss. Extra information can be obtained from the specific pattern of bone mass distribution, potential disproportionate bone losses, and method used.