Trajectory of Recovery following ORIF for Distal Radius Fractures.

Background Distal radius fractures are commonly seen among the elderly, though studies examining their long-term outcomes are limited. Purpose The aim of this study was to describe the 5-year trajectory of recovery of distal radius fractures treated with open reduction and internal fixation (ORIF). Methods Patients with distal radius fractures (AO/OTA 23.A-C) treated by ORIF were prospectively studied. Patient-Rated Wrist Evaluation (PRWE) score was measured at baseline (preinjury recall) and postoperatively at 6 months, 1 year, and 5 years. Clinically relevant change in PRWE score was assessed using the minimal clinically important difference (MCID). Results A total of 390 patients were included, of which 75% completed 5-year follow-up. Mean baseline PRWE score was 1.25 (standard deviation, SD: 2.9). At 6 months, mean PRWE score was at its highest up to 20.2 (SD: 18.4; p < 0.01). A significant improvement in mean PRWE score was observed at 1 year down to 15.2 (SD: 17.6; p < 0.01); 44% of patients were still one MCID outside of their baseline PRWE score at 1 year. Further significant improvement in mean PRWE score occurred at 5 years down to 9.4 (SD: 13.4; p < 0.01); 29% of patients remained one MCID outside of their baseline PRWE score at 5 years. Conclusion Recovery after ORIF for distal radius fractures showed significant worsening after surgery, followed by significant improvements up to 1 year and between years 1 and 5, albeit to a lesser extent. Statistically and clinically relevant wrist pain and disability persisted at 5 years. Future research should examine different treatment modalities and include a nonoperative treatment arm for comparison. Level of Evidence Prognostic level II.

Position statement: management of proximal humerus fractures.

We sought to compare outcomes and reoperation rates for the surgical treatment of proximal humerus fractures (excluding head-splitting fractures, fracture-dislocations, and isolated greater-tuberosity fractures) in men and women older than 60 years. We searched MEDLINE, Embase, and Cochrane through to Feb. 1, 2022, and included all English-language randomized trials comparing operative versus nonoperative treatment; open reduction and internal fixation (ORIF) with locking plate versus intramedullary nail; arthroplasty versus ORIF; and reverse shoulder arthroplasty versus hemiarthroplasty. Outcomes of interest were functional outcomes (e.g., Constant score), pain outcomes (visual analogue scale scores), and reoperation rates for the interventions of interest when available. We rated the quality of the evidence and strength of recommendations using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. This guideline will benefit patients considering surgical intervention for fractures of the proximal humerus by improving counselling on surgical treatment options and possible outcomes. It will also benefit surgical providers by improving their knowledge of various surgical approaches. Data presented could be used to develop frameworks and tools for shared decision-making.Nous avons cherché à comparer les résultats et les taux de réintervention à la suite d'un traitement chirurgical pour une fracture de l'humérus proximal (excluant les fractures de la tête humérale, les fractures-luxations et les fractures isolées de la grande tubérosité) chez les hommes et les femmes âgés de plus de 60 ans. Nous avons effectué des recherches dans les bases de données MEDLINE, Embase, et Cochrane jusqu'au 1er février 2022 et avons inclus tous les essais randomisés publiés en anglais comparant différents duos d'interventions : traitements chirurgicaux ou non chirurgicaux; réductions ouvertes avec fixation interne (ROFI) réalisées à l'aide d'une plaque verrouillée ou enclouages centromédullaires; arthroplasties ou ROFI; et arthroplasties inversées de l'épaule ou hémiarthroplasties. Les paramètres d'intérêt étaient la capacité fonctionnelle (p. ex., score de Constant), la douleur (p. ex., échelle analogique visuelle) et le taux de réintervention pour les interventions d'intérêt, selon les données disponibles. Nous avons évalué la qualité des données probantes et la solidité des recommandations à l'aide de l'approche GRADE (Grading of Recommendations, Assessment, Development and Evaluation). Cette ligne directrice profitera aux patients qui envisagent une intervention chirurgicale après une fracture de l'humérus proximal en améliorant les consultations sur les options de traitement chirurgical et les résultats escomptés. Elle aidera aussi les chirurgiens en améliorant leurs connaissances sur différentes approches chirurgicales. Les données présentées pourraient servir à mettre au point des cadres et des outils pour une prise de décision partagée.

Evaluation of the trajectory of recovery following surgically treated acetabular fractures.

Aims: Acetabular fractures are associated with long-term morbidity. Our prospective cohort study sought to understand the recovery trajectory of this injury over five years. Methods: Eligible patients at a level I trauma centre were recruited into a longitudinal registry of surgical acetabular fractures between June 2004 and August 2019. Patient-reported outcome measures (PROMs), including the 36-Item Short Form Health Survey (SF-36) physical component summary (PCS), were recorded at baseline pre-injury recall and six months, one year, two years, and five years postoperatively. Comparative analyses were performed for elementary and associated fracture patterns. The proportion of patients achieving minimal clinically important difference (MCID) was determined. The rate of, and time to, conversion to total hip arthroplasty (THA) was also established. Results: We recruited 251 patients (253 fractures), with a 4:1 male to female ratio and mean age of 46.1 years (SD 16.4). Associated fracture patterns accounted for 56.5% of fractures (n = 143). Trajectory analysis showed all timepoints had significant disability versus baseline, including final follow-up (p < 0.001). Elementary fractures had higher SF-36 PCS at six months (p = 0.023) and one year (p = 0.007) compared to associated fractures, but not at two years (p = 0.135) or five years (p = 0.631). The MCID in SF-36 PCS was observed in 37.3% of patients (69/185) between six months and one year, 26.9% of patients (39/145) between one and two years, and 23.3% of patients (20/86) between two and five years, highlighting the long recovery potential of these injuries. A significant proportion of patients failed to attain the MCID after five years (38.1%; 40/105). Conversion to THA occurred in 13.1% of patients (11/110 elementary and 22/143 associated fractures). Approximately two-thirds of THAs (21/33 patients; 63.6%) were performed within two years of index surgery. Conclusion: Acetabular fractures significantly impact physical function. Recovery trajectory is often elongated beyond one year, with two-thirds of our patients displaying persistent clinically relevant long-term disability.

Postfasciotomy Classification System for Acute Compartment Syndrome of the Leg.

OBJECTIVE: Acute compartment syndrome (ACS) is a true emergency. Even with urgent fasciotomy, there is often muscle damage and need for further surgery. Although ACS is not uncommon, no validated classification system exists to aid in efficient and clear communication. The aim of this study was to establish and validate a classification system for the consequences of ACS treated with fasciotomy. METHODS: Using a modified Delphi method, an international panel of ACS experts was assembled to establish a grading scheme for the disease and then validate the classification system. The goal was to articulate discrete grades of ACS related to fasciotomy findings and associated costs. A pilot analysis was used to determine questions that were clear to the respondents. Discussion of this analysis resulted in another round of cases used for 24 other raters. The 24 individuals implemented the classification system 2 separate times to compare outcomes for 32 clinical cases. The accuracy and reproducibility of the classification system were subsequently calculated based on the providers' responses. RESULTS: The Fleiss Kappa of all raters was at 0.711, showing a strong agreement between the 24 raters. Secondary validation was performed for paired 276 raters and correlation was tested using the Kendall coefficient. The median correlation coefficient was 0.855. All 276 pairs had statistically significant correlation. Correlation coefficient between the first and second rating sessions was strong with the median pair scoring at 0.867. All surgeons had statistically significant internal consistency. CONCLUSION: This new ACS classification system may be applied to better understand the impact of ACS on patient outcomes and economic costs for leg ACS.

Effect of humeral rotation on the reliability of radiographic measurements for proximal humerus fractures.

BACKGROUND: There are concerns as to the reliability of proximal humerus radiographic measurements, particularly regarding the rotational position of the humerus when obtaining radiographs. METHODS: Twenty-four patients with proximal humerus fractures fixed surgically with locked plates received postoperative anteroposterior radiographs with the humerus in neutral rotation and in 30° of internal and external rotation. Radiographic measurements for head shaft angle, humeral offset and humeral head height were performed in each humeral rotation position. Intra-class correlation coefficient was used to assess inter-rater and intra-rater reliability. Mean differences (md) in measurements between humeral positions was evaluated using one-way ANOVA. RESULTS: Head shaft angle demonstrated good-to-excellent reliability; the highest estimates for inter-rater reliability (ICC: 0.85; 95% CI: 0.76, 0.94) and intra-rater reliability (ICC: 0.96; 95% CI: 0.93, 0.98) were achieved in neutral rotation. There were significant differences in measurement values between each rotational position, with mean head shaft angle of 133.1° in external rotation, and increasingly valgus measurements in neutral (md: 7.6°; 95% CI: 5.0, 10.3°; p < 0.001) and internal rotation (md: 26.4°; 95% CI: 21.8, 30.9°; p < 0.001). Humeral head height and humeral offset showed good-to-excellent reliability in neutral and external rotation, but poor inter-rater reliability in internal rotation. Humeral head height was significantly greater using internal compared to external rotation (md: 4.5 mm; 95% CI: 1.7, 7.3 mm; p = 0.002). Humeral offset was significantly greater in external compared to internal rotation (md: 4.6 mm; 95% CI: 2.6, 6.6 mm; p < 0.001). CONCLUSIONS: Views of the humerus in neutral rotation and 30° of external rotation displayed superior reliability. Differences in radiographic measurement values, depending on humeral rotation views, can make for problematic correlations with patient outcome measures. Studies assessing radiographic outcomes following proximal humerus fractures should ensure standardized humeral rotation for obtaining anteroposterior shoulder radiographs, with neutral rotation and external rotation views likely yielding the most reliable results. LEVEL OF EVIDENCE: Level IV.

Assessing the Change in Operative Treatment Rates for Acute Midshaft Clavicle Fractures: Incorporation of Evidence-Based Surgery Results in Orthopaedic Practice.

In 2007, a randomized controlled trial (RCT) by the Canadian Orthopaedic Trauma Society (COTS) demonstrated better functional outcomes and a lower proportion of patients who developed malunion or nonunion following operative, compared with nonoperative, treatment of midshaft clavicle fractures. The primary aim of the present study was to compare the proportion of midshaft clavicle fractures treated operatively prior to and following the publication of the COTS RCT. An additional exploratory aim was to assess whether the proportion of midshaft clavicle fractures that were treated with surgery for malunion or nonunion decreased. Methods: This retrospective cohort analysis used population-level administrative health data on the residents of British Columbia, Canada. Cases were identified by International Classification of Diseases, Ninth Revision (ICD-9) diagnostic codes and procedure fee codes. Adult patients (≥18 years) with closed middle-third clavicle fractures between 1997 and 2018 were included. Multivariable logistic regression modeling compared the proportion of clavicle fractures treated operatively before and after January 1, 2007, controlling for patient factors. The Pearson chi-square test compared the proportion of fractures treated operatively for malunion or nonunion in the cohorts. Results: A total of 52,916 patients were included (mean age, 47.5 years; 65.6% male). More clavicle fractures were treated operatively from 2007 onward: 6.9% compared with 2.2% prior to 2007 (odds ratio [OR] = 3.35, 95% confidence interval [CI] = 3.03 to 3.70, p < 0.001). Male sex, moderate-to-high income, and younger age were associated with a greater proportion of operative fixation. The rate of surgery for clavicle malunion or nonunion also increased over this time period (to 4.1% from 3.4%, OR = 1.26, 95% CI = 1.15 to 1.38, p < 0.001). Conclusions: We found a significant change in surgeon practice regarding operative management of clavicle fractures following the publication of a Level-I RCT. With limited high-quality trials comparing operative and nonoperative management, it is important that clinicians, health-care institutions, and health-authority administrations determine what steps can be taken to increase responsiveness to new clinical studies and evidence-based guidelines. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Evaluating femoral augmentation to prevent geriatric hip fracture: A scoping review of experimental methods.

Various femoral augmentation designs have been investigated over the past decade for the prevention of geriatric hip fracture. The experimental methods used to evaluate the efficacy of these augmentations have not been critically evaluated or compared in terms of biofidelity, robustness, or ease of application. Such parameters have significant relevance in characterizing future clinical success. In this study we aimed to use a scoping review to summarize the experimental studies that evaluate femoral augmentation approaches, and critically evaluate commonly applied protocols and identify areas for concordance with the clinical situation. We conducted a literature search targeting studies that used experimental test methods to evaluate femoral augmentation to prevent geriatric fragility fracture. A total of 25 studies met the eligibility criteria. The most commonly investigated augmentation to date is the injection of bone cement or another material that cured in situ, and a popular subsequent method for biomechanical evaluation was to load the augmented proximal femur until fracture in a sideways fall configuration. We noted limitations in the clinical relevance of sideways fall scenarios being modeled and large variance in the concordance of many of the studies identified. Our review brings about recommendations for enhancing the fidelity of experimental methods modeling clinical sideways falls, which include an improved representation of soft tissue effects, using outcome metrics beyond load-to-failure, and applying loads inertially. Effective augmentations are encouraging for their potential to reduce the burden of hip fracture; however, the likelihood of this success is only as strong as the methods used in their evaluation.

Separating Daily 1 km PM2.5 Inorganic Chemical Composition in China since 2000 via Deep Learning Integrating Ground, Satellite, and Model Data.

Fine particulate matter (PM2.5) chemical composition has strong and diverse impacts on the planetary environment, climate, and health. These effects are still not well understood due to limited surface observations and uncertainties in chemical model simulations. We developed a four-dimensional spatiotemporal deep forest (4D-STDF) model to estimate daily PM2.5 chemical composition at a spatial resolution of 1 km in China since 2000 by integrating measurements of PM2.5 species from a high-density observation network, satellite PM2.5 retrievals, atmospheric reanalyses, and model simulations. Cross-validation results illustrate the reliability of sulfate (SO42-), nitrate (NO3-), ammonium (NH4+), and chloride (Cl-) estimates, with high coefficients of determination (CV-R2) with ground-based observations of 0.74, 0.75, 0.71, and 0.66, and average root-mean-square errors (RMSE) of 6.0, 6.6, 4.3, and 2.3 µg/m3, respectively. The three components of secondary inorganic aerosols (SIAs) account for 21% (SO42-), 20% (NO3-), and 14% (NH4+) of the total PM2.5 mass in eastern China; we observed significant reductions in the mass of inorganic components by 40-43% between 2013 and 2020, slowing down since 2018. Comparatively, the ratio of SIA to PM2.5 increased by 7% across eastern China except in Beijing and nearby areas, accelerating in recent years. SO42- has been the dominant SIA component in eastern China, although it was surpassed by NO3- in some areas, e.g., Beijing-Tianjin-Hebei region since 2016. SIA, accounting for nearly half (∼46%) of the PM2.5 mass, drove the explosive formation of winter haze episodes in the North China Plain. A sharp decline in SIA concentrations and an increase in SIA-to-PM2.5 ratios during the COVID-19 lockdown were also revealed, reflecting the enhanced atmospheric oxidation capacity and formation of secondary particles.

The efficacy of femoral augmentation for hip fracture prevention using ceramic-based cements: A preliminary experimentally-driven finite element investigation.

Femoral fractures due to sideways falls continue to be a major cause of concern for the elderly. Existing approaches for the prevention of these injuries have limited efficacy. Prophylactic femoral augmentation systems, particularly those involving the injection of ceramic-based bone cements, are gaining more attention as a potential alternative preventative approach. We evaluated the mechanical effectiveness of three variations of a bone cement injection pattern (basic ellipsoid, hollow ellipsoid, small ellipsoid) utilizing finite element simulations of sideways fall impacts. The basic augmentation pattern was tested with both high- and low-strength ceramic-based cements. The cement patterns were added to the finite element models (FEMs) of five cadaveric femurs, which were then subject to simulated sideways falls at seven impact velocities ranging from 1.0 m/s to 4.0 m/s. Peak impact forces and peak acetabular forces were examined, and failure was evaluated using a strain-based criterion. We found that the basic HA ellipsoid provided the highest increases in both the force at the acetabulum of the impacted femur ("acetabular force", 55.0% ± 22.0%) and at the force plate ("impact force", 37.4% ± 15.8%). Changing the cement to a weaker material, brushite, resulted in reduced strengthening of the femur (45.2% ± 19.4% acetabular and 30.4% ± 13.0% impact). Using a hollow version of the ellipsoid appeared to have no effect on the fracture outcome and only a minor effect on the other metrics (54.1% ± 22.3% acetabular force increase and 35.3% ± 16.0% impact force increase). However, when the outer two layers of the ellipsoid were removed (small ellipsoid), the force increases that were achieved were only 9.8% ± 5.5% acetabular force and 8.2% ± 4.1% impact force. These results demonstrate the importance of supporting the femoral neck cortex to prevent femoral fractures in a sideways fall, and provide plausible options for prophylactic femoral augmentation. As this is a preliminary study, the surgical technique, the possible effects of trabecular bone damage during the augmentation process, and the effect on the blood supply to the femoral head must be assessed further.

What are the optimal targeting visualizations for performing surgical navigation of iliosacral screws? A user study.

INTRODUCTION: Complex orthopaedic procedures, such as iliosacral screw (ISS) fixations, can take advantage of surgical navigation technology to achieve accurate results. Although the impact of surgical navigation on outcomes has been studied, no studies to date have quantified how the design of the targeting display used for navigation affects ISS targeting performance. However, it is known in other contexts that how task information is displayed can have significant effects on both accuracy and time required to perform motor tasks, and that this can be different among users with different experience levels. This study aimed to investigate which visualization techniques helped experienced surgeons and inexperienced users most efficiently and accurately align a surgical tool to a target axis. METHODS: We recruited 21 participants and conducted a user study to investigate five proposed 2D visualizations (bullseye, rotated bullseye, target-fixed, tool-fixed in translation, and tool-fixed in translation and rotation) with varying representations of the ISS targets and tool, and one 3D visualization. We measured the targeting accuracy achieved by each participant, as well as the time required to perform the task using each of the visualizations. RESULTS: We found that all 2D visualizations had equivalent translational and rotational errors, with mean translational errors below 0.9 mm and rotational errors below 1.1[Formula: see text]. The 3D visualization had statistically greater mean translational and rotational errors (4.29 mm and 5.47[Formula: see text], p < 0.001) across all users. We also found that the 2D bullseye view allowed users to complete the simulated task most efficiently (mean 30.2 s; 95% CI 26.4-35.7 s), even when combined with other visualizations. CONCLUSIONS: Our results show that 2D bullseye views helped both experienced orthopaedic trauma surgeons and inexperienced users target iliosacral screws accurately and efficiently. These findings could inform the design of visualizations for use in a surgical navigation system for screw insertions for both training and surgical practice.

Evolution of Ozone Pollution in China: What Track Will It Follow?

Increasing surface ozone (O3) concentrations has emerged as a key air pollution problem in many urban regions worldwide in the last decade. A longstanding major issue in tackling ozone pollution is the identification of the O3 formation regime and its sensitivity to precursor emissions. In this work, we propose a new transformed empirical kinetic modeling approach (EKMA) to diagnose the O3 formation regime using regulatory O3 and NO2 observation datasets, which are easily accessible. We demonstrate that mapping of monitored O3 and NO2 data on the modeled regional O3-NO2 relationship diagram can illustrate the ozone formation regime and historical evolution of O3 precursors of the region. By applying this new approach, we show that for most urban regions of China, the O3 formation is currently associated with a volatile organic compound (VOC)-limited regime, which is located within the zone of daytime-produced O3 (DPO3) to an 8h-NO2 concentration ratio below 8.3 ([DPO3]/[8h-NO2] ≤ 8.3). The ozone production and controlling effects of VOCs and NOx in different cities of China were compared according to their historical O3-NO2 evolution routes. The approach developed herein may have broad application potential for evaluating the efficiency of precursor controls and further mitigating O3 pollution, in particular, for regions where comprehensive photochemical studies are unavailable.

Management of Proximal Humeral Fractures in Adults: A Systematic Review and Meta-Analysis.

OBJECTIVES: Differences in function, pain, and reoperation rates were compared between the following treatment options: (1) operative vs. nonoperative treatment and (2) various surgical treatments including open reduction internal fixation, intramedullary nail, hemiarthroplasty (HA), and reverse shoulder arthroplasty (RSA). DATA SOURCES: MEDLINE, Embase, and Cochrane were searched through February 1, 2022. All English-language randomized trials comparing operative and nonoperative treatment of proximal humeral fractures with a control group in patients 18 years or older were included. DATA EXTRACTION: Demographic data, functional and pain scores and re-operation rates were extracted. Study quality was determined with the Cochran risk of bias tool and the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE). Heterogeneity was determined with the I-squared statistic. DATA SYNTHESIS: Meta-analysis of included studies using mean difference and odds ratios where appropriate. CONCLUSIONS: Surgical treatment with either locked plates or HA results in similar functional scores and pain outcomes as nonoperative treatment, although plates were associated with higher reoperation rates in 3-part and 4-part fractures. In 3-part and 4-part fractures, RSA results in higher function and pain scores compared with HA. Further high-quality trials should focus on RSA, and further study is required to better define the role of open reduction internal fixation in the younger patient population. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Progression of histological lesions after ABO incompatible kidney transplantation.

Recent large meta-analyses suggested a poorer long-term patients' and grafts' outcomes after ABO incompatible (ABOi) living-donor kidney transplantation (LDKT) compared to ABO compatible LDKT. However, little is known about the long-term histological pattern after ABOi LDKT. We compared the histological features observed on protocol biopsies from 03/11 to 11/19 in 94 ABOi LDKT (including 14 with preformed Donor Specific Antibodies, pDSAs), 27 LDKT ABO compatible (ABOc) with pDSAs, and 21 ABOc without pDSAs) during the first five years post transplantation. During the first 5 years post-transplantation, a progression of chronic lesions (patients with a ci >0 raised from 11% to 65%, p<0.0001, patients with a ct >0 raised from 29% to 78%, p<0.0001) was observed in ABOi LDKT without pDSAs. Histological patterns of evolution were comparable to those observed in ABOc kidney transplant patients. Microvascular inflammation was lower in ABOi LDKT without pDSAs compared to those with pDSAs (ABOi or ABOc). At last follow-up, 28 months, IQR (15-48) post-transplantation, 29 patients (36%) had a severe graft dysfunction (defined by a CKD-epi eGFR < 30 mL/min/1.73m²). The donor age was a predictive factor for the development of severe kidney allograft dysfunction at last follow-up (HR= 1.05, 95% CI [1.05-1.10], p= 0.03). Hence, long-term histological analysis of ABOi LDKT shows only an increase of chronic interstitial and tubular atrophy changes, without active lesions. These data confirm that ABOi LDKT programs can be securely developed.

Risk Factors for the Development of Heterotopic Ossification Following Acetabular Fractures: A Systematic Review.

BACKGROUND: Heterotopic ossification (HO) following acetabular fractures is a common complication that may affect clinical outcomes. However, the effects of prophylactic treatment with nonsteroidal anti-inflammatory drugs or radiation therapy remain controversial. While several factors have been related to the development of HO, there is considerable uncertainty regarding their importance or effect size in the setting of acetabular surgery. Therefore, this systematic review aims to summarize the risk factors for HO following the operative fixation of acetabular fractures and clarify their interrelationships. METHODS: In accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, PubMed, MEDLINE, Embase, and CINAHL databases were searched from inception to February 2021. Studies that assessed factors related to HO development among patients with operatively repaired acetabular fractures were included. Outcomes were risk factors and their effect size (p values, odds ratios, and 95% confidence intervals). RESULTS: Twenty-five studies and 1 conference abstract with a total of 3,940 patients were included. The following risk factors for HO were identified. Patient factors were increased body mass index, male sex, and increased age. Injury factors were intensive care unit (ICU) admission and length of stay, non-ICU hospitalization for >10 days, the need for mechanical ventilation for ≥2 days, abdominal and/or chest injuries, the number and type of associated fractures, traumatic brain injuries, T-type acetabular fractures, pelvic ring injuries, and hip dislocation. Care factors were a delay to surgery, extensile and posterior surgical approaches to the hip, trochanteric osteotomy, postoperative step-off of >3 mm, and a delay to prophylaxis following injury or surgery. Ethnicity, Injury Severity Score, cause of the fracture, femoral head injuries, degloving injuries, comminution, intra-articular debris, the type of bone void filler, gluteus minimus muscle preservation, prolonged operative time, and intraoperative patient position were not risk factors for developing HO. CONCLUSIONS: HO following operative fixation of acetabular fractures is not uncommon, with severe-grade HO associated with substantial disability. Careful consideration of the risk factor effect sizes and interdependencies could aid physicians in identifying patients at risk for developing HO and guide their prophylactic management. The results of this study could establish a framework for future studies. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Can uncertainty estimation predict segmentation performance in ultrasound bone imaging?

PURPOSE: Segmenting bone surfaces in ultrasound (US) is a fundamental step in US-based computer-assisted orthopaedic surgeries. Neural network-based segmentation techniques are a natural choice for this, given promising results in related tasks. However, to gain widespread use, we must be able to know how much to trust segmentation networks during clinical deployment when ground-truth data is unavailable. METHODS: We investigated alternative ways to measure the uncertainty of trained networks by implementing a baseline U-Net trained on a large dataset, together with three uncertainty estimation modifications: Monte Carlo dropout, test time augmentation, and ensemble learning. We measured the segmentation performance, calibration quality, and the ability to predict segmentation performance on test data. We further investigated the effect of data quality on these measures. RESULTS: Overall, we found that ensemble learning with binary cross-entropy (BCE) loss achieved the best segmentation performance (mean Dice: 0.75-0.78 and RMS distance: 0.62-0.86mm) and the lowest calibration errors (mean: 0.22-0.28%). In contrast to previous studies of area or volumetric segmentation, we found that the resulting uncertainty measures are not reliable proxies for surface segmentation performance. CONCLUSION: Our experiments indicate that a significant performance and confidence calibration boost can be achieved with ensemble learning and BCE loss, as tested on 13,687 US images containing various anatomies and imaging parameters. However, these techniques do not allow us to reliably predict future segmentation performance. The results of this study can be used to improve the calibration and performance of US segmentation networks.

Responsiveness of the PROMIS physical function measure in orthopaedic trauma patients.

OBJECTIVES: To compare the responsiveness of the Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF) to the 36-Item Short Form Survey Physical Component Score (SF36-PCS) in orthopaedic trauma patients from pre-injury to one year recovery. DESIGN AND SETTING: Prospective cohort study at a Level 1 trauma centre. PARTICIPANTS: Patients over the age of 18 with orthopaedic trauma injuries to the pelvis, lower extremity or upper extremity between 2017 and 2018. MAIN OUTCOMES MEASUREMENTS: The PROMIS-PF and SF36-PCS assessments were conducted at baseline, 3 months, 6 months and 12 months. Responsiveness of each measure was assessed between time points by calculating the standardized response mean (SRM), the proportions of patients exceeding minimal clinically important difference (MCID), and the floor and ceiling effects. RESULTS: Sixty-eight patients with completed assessments at every timepoint were included: mean age 44.7 years, 39 were male and mean Injury Severity Score (ISS) was 7.4 (range: 4-16). Mean time of completion for the SF-36 at all the time points was 5.6 min vs 1.7 min for the PROMIS-PF (p<0.01). The SRM was comparable between measures at all the time points. Although a greater proportion of patients achieved MCID for SF36-PCS between all the time points, this only approached statistical significance between the 6- and 12-month assessments (47.1% vs 33.8%; p = 0.15). There was a significant ceiling effect demonstrated with the PROMIS-PF at baseline and 12-month assessments, with 34 (50.0%) patients and 7 (10.3%) patients achieving the maximum scores at each time point, respectively. DISCUSSION AND CONCLUSIONS: PROMIS-PF has a more favourable responder burden based on lower time to completion and comparable responsiveness to the SF-36 PCS. However, there are limitations in responsiveness with the PROMIS-PF in patients who are higher functioning as demonstrated by the ceiling effects in patients at baseline pre-injury and at 12 months post-injury timepoints.

Quantifying Urinary and Sexual Dysfunction After Pelvic Fracture.

OBJECTIVES: To quantify the severity of urinary and sexual dysfunction and to evaluate the relationship between urinary and sexual dysfunction, injury, and treatment factors in patients with pelvic fracture. DESIGN: Prospective cohort study. SETTING: Level 1 trauma center. PATIENTS/PARTICIPANTS: One hundred thirteen patients with surgically treated pelvic fracture (65.5% OTA/AO 61B fractures; 7 open fractures; 74 men). INTERVENTIONS: Surgical pelvic stabilization. MAIN OUTCOME MEASURES: The 36-Item Short Form Health Survey and International Consultation Incontinence Questionnaire responses were collected at baseline, 6 months, and 1, 2, and 5 years. Patients were scored on symptoms of voiding and incontinence, and filling (for women), to derive urinary function. Sexual function was scored as a single domain. Both genders reported urinary and sexual bothersome symptoms. Regression analysis was used to isolate the importance of predictive factors on urinary and sexual function, urinary and sexual bother, and their impact on quality of life. RESULTS: Patients with pelvic fracture have significant urinary and sexual dysfunction, which is sustained or worsens over time. Male urinary function was predicted by Injury Severity Score (P = 0.03) and 61C fracture (odds ratio: 3.23, P = 0.04). Female urinary function was predicted by urinary tract injury at admission (odds ratio: 7.57, P = 0.03). Neurologic injury and anterior fixation were identified as significant predictors for male sexual function and sexual bother, whereas urological injuries were important in predicting female urinary and sexual bother (P < 0.01). Sexual function (P = 0.02) and sexual bother (P < 0.001) were important predictors of overall mental well-being in men. CONCLUSIONS: Urinary and sexual dysfunction are prevalent and sustained in men and women and do not follow the prolonged slow recovery trajectory seen in physical function. Male urinary and sexual dysfunction was closely tied to neurologic injury, whereas female urinary and sexual dysfunction was predicted by the presence of a urinary tract injury. Urinary and sexual dysfunction were important to overall mental well-being in men. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Prophylactic augmentation implants in the proximal femur for hip fracture prevention: An in silico investigation of simulated sideways fall impacts.

Femoral fractures from sideways falls in the elderly are associated with significant rates of morbidity and mortality. Approaches to prevent these catastrophic injuries include pharmacological treatments, which have limited efficacy. Prophylactic femoral augmentation systems are a promising alternative that are gaining prominence by addressing the most debilitating osteoporosis-related fracture. We have developed finite element models (FEMs) of a novel experimental sideways fall simulator for cadavers. By virtue of the range of specimens and injury outcomes, these FEMs are well-suited to the evaluation of such implants. The purpose of this study was to use the FEMs to evaluate the mechanical effectiveness of three different prophylactic femoral augmentation systems. Models of the Y-Strut® (Hyprevention®, Pessac, France), Gamma Nail® (Stryker, Kalamazoo, USA), and a simple lag screw femoral fracture implant systems were placed into FEMs of five cadaveric pelvis-femur constructs embedded in a soft tissue surrogate, which were then subject to simulated sideways falls at seven impact velocities. Femur-only FEMs were also evaluated. Peak impact forces and peak acetabular forces were examined, and failure was evaluated using a strain-based criterion. We found that the femoral augmentation systems increased the peak forces prior to fracture, but were unable to prevent fracture for severe impacts. The Gamma Nail® system consistently produced the largest strength increases relative to the unaugmented femur for all five specimens in both the pendulum-drop FEMs and the femur-only simulations. In some cases, the same implant appeared to cause fractures in the acetabulum. The femur-only FEMs showed larger force increases than the pendulum-drop simulations, which suggests that the results of the femur-only simulations may not represent sideways falls as accurately as the soft tissue-embedded pendulum-drop simulations. The results from this study demonstrate the ability to simulate a high energy phenomenon and the effect of implants in an in silico environment. The results also suggest that implants could increase the force applied to the proximal femur during impact. Fracture outcomes from the tested implants can be used to inform the design of future devices, which reaffirms the value of modelling with biofidelic considerations in the implant design process. To the authors' knowledge, this is the first paper to use more complex biofidelic FEMs to assess prophylactic femoral augmentation methods.

Long-Term Trajectory of Recovery Following Pilon Fracture Fixation.

OBJECTIVES: To describe the trajectory of recovery following fixation of pilon fractures from baseline to 5-year follow-up. DESIGN: Prospective cohort study. SETTING: Level-1 trauma center. PATIENTS/PARTICIPANTS: Patients with pilon fractures (OTA/AO 43.C) treated with open reduction and internal fixation. INTERVENTION: None. MAIN OUTCOMES MEASURES: Patient-reported outcome measures were measured at baseline, 6 months, 1 year, and 5 years using the Short-Form 36 Health Survey (SF-36) Physical Component Score and Mental Component Score, Short Musculoskeletal Functional Assessment, and the Foot and Ankle Outcome Score. RESULTS: One hundred two patients were enrolled: mean age was 42.6 years; 69% were males; 88% had an injury severity score of 9; 74 patients (73%) completed 1-year follow-up; 40 patients (39%) completed 5-year follow-up. Trajectory of recovery of physical function showed a significant decline between baseline and 6 months, with significant improvement between 6 months and 1 year and then ongoing but slower improvement between 1 year and 5 years. Sixty-four patients returned to baseline SF-36 Physical Component Score at 5 years. Pain was a persistent issue and remained significantly worse at 5 years when compared with baseline. Psychological well-being (SF-36 Mental Component Score) did not significantly change from baseline at 5 years. CONCLUSION: Functional recovery following open reduction and internal fixation for pilon fractures was characterized by an initial decrease in function from baseline, followed by an increase between 6 months and 1 year, and then slower but continued increases from 1 year to 5 years. Function did not return to baseline levels, pain was a persistent issue, and mental well-being showed no change from baseline at 5 years. This information may be useful when counselling patients. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.