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.

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.

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.

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.

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.

How should we lengthen post-traumatic limb defects? a systematic review and comparison of motorized lengthening systems, combined internal and external fixation and external fixation alone.

PURPOSE: Various external fixation systems for lower extremity long bone deformities have been used to various degrees of success, while newer mechanical lengthening nail (MLN) systems offer the potential for improved patient outcomes. Proponents of MLNs argue that they reduce the number of operations, infectious complications, and improve quality of life; however, the evidence to support these claims is scant. This systematic review aims to evaluate the optimal lengthening system for treating post-traumatic long bone deformity. METHODS: The systematic review was conducted in accordance with PRISMA guidelines. PUBMED, EMBASE, CINAHL, and the Cochrane Library were searched for comparative studies of lengthening techniques among adult patients with axial deformities. Studies were screened and data extracted in duplicate. Treatment groups were pooled into external fixation (EF) alone, combined internal and external fixation (CIF), and mechanical lengthening nail (MLN). Outcomes were mean lengthening achieved, lengthening index, and reported complications. RESULTS: Thirteen studies with 725 patients (mean age: 29.6 years, 74% male) were included. Nearly all of the studies were either prospective or retrospective cohort studies (n = 12), with one randomized controlled trial of moderate study quality. The mean limb lengthening achieved, lengthening index, and rate of reoperation were similar among the MLN, EF, and CIF groups. CONCLUSION: The purported decreased the duration of lengthening and the risk of reoperation associated with MLNs was not demonstrated in this review. Patients with post-traumatic leg length deformities remain a challenging patient population to treat, with intervention being associated with high rates of infectious complications and need for revision operations.

Globular structure of the hypermineralized tissue in human femoral neck.

Bone becomes more fragile with ageing. Among many structural changes, a thin layer of highly mineralized and brittle tissue covers part of the external surface of the thin femoral neck cortex in older people and has been proposed to increase hip fragility. However, there have been very limited reports on this hypermineralized tissue in the femoral neck, especially on its ultrastructure. Such information is critical to understanding both the mineralization process and its contributions to hip fracture. Here, we use multiple advanced techniques to characterize the ultrastructure of the hypermineralized tissue in the neck across various length scales. Synchrotron radiation micro-CT found larger but less densely distributed cellular lacunae in hypermineralized tissue than in lamellar bone. When examined under FIB-SEM, the hypermineralized tissue was mainly composed of mineral globules with sizes varying from submicron to a few microns. Nano-sized channels were present within the mineral globules and oriented with the surrounding organic matrix. Transmission electron microscopy showed the apatite inside globules were poorly crystalline, while those at the boundaries between the globules had well-defined lattice structure with crystallinity similar to the apatite mineral in lamellar bone. No preferred mineral orientation was observed both inside each globule and at the boundaries. Collectively, we conclude based on these new observations that the hypermineralized tissue is non-lamellar and has less organized mineral, which may contribute to the high brittleness of the tissue.

Comprehensive Geriatric Care to Improve Mobility after Hip Fracture: An RCT.

BACKGROUND: Comprehensive geriatric care (CGC) for older adults during hospitalization for hip fracture can improve mobility, but it is unclear whether CGC delivered after a return to community living improves mobility compared with usual post-discharge care. OBJECTIVE: To determine if an outpatient clinic-based CGC regime in the first year after hip fracture improved mobility performance at 12 months. METHODS: A two-arm, 1:1 parallel group, pragmatic, single-blind, single-center, randomized controlled trial at 3 hospitals in Vancouver, BC, Canada. Participants were community-dwelling adults, aged ≥65 years, with a hip fracture in the previous 3-12 months, who had no dementia and walked ≥10 m before the fracture occurred. Target enrollment was 130 participants. Clinic-based CGC was delivered by a geriatrician, physiotherapist, and occupational therapist. Primary outcome was the Short Physical Performance Battery (SPPB; 0-12) at 12 months. RESULTS: We randomized 53/313 eligible participants with a mean (SD) age of 79.7 (7.9) years to intervention (n = 26) and usual care (UC, n = 27), and 49/53 (92%) completed the study. Mean 12-month (SD) SPPB scores in the intervention and UC groups were 9.08 (3.03) and 8.24 (2.44). The between-group difference was 0.9 (95% CI -0.3 to 2.0, p = 0.13). Adverse events were similar in the 2 groups. CONCLUSION: The small sample size of less than half our recruitment target precludes definitive conclusions about the effect of our intervention. However, our results are consistent with similar studies on this population and intervention.

Variation in surgical demand and time to hip fracture repair: a Canadian database study.

BACKGROUND: Competing demands for operative resources may affect time to hip fracture surgery. We sought to determine the time to hip fracture surgery by variation in demand in Canadian hospitals. METHODS: We obtained discharge abstracts of 151,952 patients aged 65 years or older who underwent surgery for a hip fracture between January, 2004 and December, 2012 in nine Canadian provinces. We compared median time to surgery (in days) when demand could be met within a two-day benchmark and when demand required more days, i.e. clearance time, to provide surgery, overall and stratified by presence of medical reasons for delay. RESULTS: For persons admitted when demand corresponded to a 2-day clearance time, 68% of patients underwent surgery within the 2-day benchmark. When demand corresponded to a clearance time of one week, 51% of patients underwent surgery within 2 days. Compared to demand that could be served within the two-day benchmark, adjusted median time to surgery was 5.1% (95% confidence interval [CI] 4.1-6.1), 12.2% (95% CI 10.3-14.2), and 22.0% (95% CI 17.7-26.2) longer, when demand required 4, 6, and 7 or more days to clear the backlog, respectively. After adjustment, delays in median time to surgery were similar for those with and without medical reasons for delay. CONCLUSION: Increases in demand for operative resources were associated with dose-response increases in the time needed for half of hip fracture patients to undergo surgery. Such delays may be mitigated through better anticipation of day-to-day supply and demand and increased response capability.

Using Laser Range-finding to Measure Bore Depth in Surgical Drilling of Bone.

BACKGROUND: Measuring drilled bore depth in bone is an important part of osteosynthesis surgery. Current methods have substantial limitations in terms of reliability, leading to placement of incorrectly sized screws and unsatisfactory user experience. QUESTIONS/PURPOSES: (1) Can a prototype laser range-finder measure bore depth in bone as well as or better than a conventional depth gauge in terms of accuracy and precision (that is, variability)? METHODS: A conventional analog orthopaedic surgical depth gauge was compared with a laser range-finder-based prototype. Experiments were conducted on four pig hind limbs, with bicortical holes drilled in the femur and the tibia. Two surgeons alternated drilling bores in three different clinically relevant conditions: straight drilling through the diaphysis, angled drilling through the diaphysis, and straight drilling through the metaphysis. Depth measurements were taken with the laser range-finder-based prototype, and the conventional depth gauge and compared against depth measurements obtained from a CT image that served as the reference measurement. RESULTS: In straight diaphyseal drilling the laser range-finder-based prototype had a larger mean error of 1.34 mm (± 0.7 mm) compared with a mean error of -0.06 mm (± 1.38 mm) using the conventional gauge (95% CI 0.824 to 1.976; p < 0.001). In angled diaphyseal drilling, there was no difference in mean error between the laser range-finder-based prototype (1.66 ± 0.86 mm) and the conventional gauge (2.36 ± 3.79 mm [95% CI -2.338 to 0.938]; p = 0.393). In straight metaphyseal drilling, there was no difference in mean error between the laser range-finder-based prototype (2.11 ± 0.8 mm) and the conventional gauge (1.51 ± 3.19 mm [95% CI -0.500 to 1.700]; p = 0.280). The laser range-finder-based prototype had greater precision (smaller variance) than the conventional depth gauge in straight diaphyseal drilling (p < 0.001), angled diaphyseal drilling (p < 0.001), and straight metaphyseal drilling (p < 0.001). CONCLUSIONS: A laser range-finder-based prototype mounted on a conventional surgical drill demonstrated overall similar accuracy and better precision in measuring drilled bore depth in bone compared with the conventional depth gauge. CLINICAL RELEVANCE: A device based on this concept could improve the reliability of bore depth measurement in surgical practice and could therefore reduce the frequency of screw replacement and associated complications.

Mortality effects of timing alternatives for hip fracture surgery.

BACKGROUND: The appropriate timing of hip fracture surgery remains a matter of debate. We sought to estimate the effect of changes in timing policy and the proportion of deaths attributable to surgical delay. METHODS: We obtained discharge abstracts from the Canadian Institute for Health Information for hip fracture surgery in Canada (excluding Quebec) between 2004 and 2012. We estimated the expected population-average risks of inpatient death within 30 days if patients were surgically treated on day of admission, inpatient day 2, day 3 or after day 3. We weighted observations with the inverse propensity score of surgical timing according to confounders selected from a causal diagram. RESULTS: Of 139 119 medically stable patients with hip fracture who were aged 65 years or older, 32 120 (23.1%) underwent surgery on admission day, 60 505 (43.5%) on inpatient day 2, 29 236 (21.0%) on day 3 and 17 258 (12.4%) after day 3. Cumulative 30-day in-hospital mortality was 4.9% among patients who were surgically treated on admission day, increasing to 6.9% for surgery done after day 3. We projected an additional 10.9 (95% confidence interval [CI] 6.8 to 15.1) deaths per 1000 surgeries if all surgeries were done after inpatient day 3 instead of admission day. The attributable proportion of deaths for delays beyond inpatient day 2 was 16.5% (95% CI 12.0% to 21.0%). INTERPRETATION: Surgery on admission day or the following day was estimated to reduce postoperative mortality among medically stable patients with hip fracture. Hospitals should expedite operating room access for patients whose surgery has already been delayed for nonmedical reasons.

Neurostimulation for Refractory Cervicogenic Headache: A Three-Year Retrospective Study.

BACKGROUND: Occipital nerve stimulation (ONS) has been used for the treatment of neuropathic pain conditions and could be a therapeutic approach for refractory cervicogenic headache (CeH). AIM: The aim of this study is to assess the efficacy and safety of unilateral ONS in patients suffering from refractory CeH. METHODS: We conducted a retrospective chart review on patients implanted from 2011 to 2013 at CHUM. The primary outcome was a 50% reduction in headache days per month. Secondary outcomes included change in EuroQol Group Visual Analog Scale rating of health-related quality of life (EQ VAS), six item headache impact test (HIT-6) score, hospital anxiety and depression scale (HADS) score, work status, and medication overuse. RESULTS: Sixteen patients fulfilled the inclusion criteria; they had suffered from daily moderate to severe CeH for a median of 15 years. At one year follow-up, 11 patients were responders (69%). There was a statistically significant improvement in the EQ VAS score (median change: 40 point increase, p = 0.0013) and HIT-6 score (median change: 17.5 point decrease, p = 0.0005). Clinically significant anxiety and depression scores both resolved amongst 60% of patients. At three years, six patients were responders (37.5%). Out of the 11 responders at one-year post implantation, five had remained headache responders (R-R) and one additional patient became a responder (NR-R). There was a statistically significant improvement in the EQ VAS score (median change: 15 point increase, p = 0.019) and HIT-6 score (median change: 7.5 point decrease, p = 0.0017) compared with baseline. Clinically significant anxiety and depression scores both, respectively, resolved among 22.5% and 33.9% of patients. Five out of seven disabled patients were back to work. CONCLUSION: ONS may be a safe and effective treatment modality for patients suffering from a refractory CeH. Further study may be warranted.

The burden of second hip fractures: provincial surgical hospitalizations over 15 years.

BACKGROUND: Second hip fractures account for up to 15% of all hip fractures. We sought to determine if the proportion of hip fracture surgeries for second hip fracture changed over time in terms of patient and fracture characteristics. METHODS: We reviewed the records of patients older than 60 years hospitalized for hip fracture surgery between 1990 and 2005 in British Columbia. We studied the proportion of surgeries for second hip fracture among all hip fracture surgeries. Linear regression tested for trends across fiscal years for women and men. RESULTS: We obtained 46 341 patient records. Second hip fracture accounted for 8.3% of hip fracture surgeries. For women the proportion of second hip fracture surgeries increased linearly from 4% to 13% with each age decade (p = 0.001) and across fiscal years (p = 0.002). In men the proportion of second hip fracture surgeries was 5% for each age decade between the ages of 60 and 90 years across fiscal years, increasing to 8% for men older than 90 years across fiscal years (p = 0.20). These sex-specific trends were similar for both pertrochanteric and transcervical fracture types. CONCLUSION: Second hip fracture surgeries account for an increasing proportion of hip fracture surgeries and may require more health care resources to minimize poorer reported outcomes. Future research should determine whether more health care resources are required to manage these patients and optimize their outcomes.

CONTEXTE: Les secondes fractures de la hanche représentent jusqu'à 15 % de la totalité des fractures de la hanche. Nous avons tenté de déterminer si la proportion de chirurgies de seconde fracture de la hanche avait évolué au fil du temps sur le plan des caractéristiques des patients et des fractures. MÉTHODES: Nous avons examiné les dossiers des patients de 60 ans et plus qui avaient été hospitalisés pour une chirurgie de fracture de la hanche entre 1990 et 2005, en Colombie-Britannique. De ce total, nous avons ensuite déterminé le nombre de chirurgies de seconde fracture de la hanche. L'analyse de régression linéaire a déterminé les tendances au cours des années financières pour les femmes et les hommes. RÉSULTATS: Nous avons obtenu 46 341 dossiers de patient. Les secondes fractures de la hanche représentaient 8,3 % de la totalité des chirurgies de fracture de la hanche. Chez les femmes, la proportion de seconde fracture de la hanche augmentait de façon linéaire de 4 % à 13 % pour chaque tranche d'âge de 10 ans (p = 0,001) et sur l'ensemble des années financières (p = 0,002). Chez les hommes, la proportion de chirurgies de seconde fracture de la hanche était de 5 % pour chaque tranche d'âge de 10 ans entre 60 et 90 ans et sur l'ensemble des années financières, et augmentait à 8 % pour les hommes de plus de 90 ans sur l'ensemble des années financières (p = 0,20). Ces tendances selon le sexe étaient similaires tant pour les fractures pertrochantériennes que pour les fractures transcervicales. CONCLUSION: Les chirurgies de seconde fracture de la hanche représentent une proportion croissante de la totalité des chirurgies de fracture de la hanche et pourraient nécessiter davantage de ressources en soins de santé pour minimiser les résultats moins bons signalés. Les recherches futures devraient déterminer s'il faut davantage de ressources de soins de santé pour la prise en charge de ces patients et l'optimisation de leurs résultats.

In-hospital mortality after hip fracture by treatment setting.

BACKGROUND: Where patients with hip fracture undergo treatment may influence their outcome. We compared the risk of in-hospital death after hip fracture by treatment setting in Canada. METHODS: We examined all discharge abstracts from the Canadian Institute for Health Information with diagnosis codes for hip fracture involving patients 65 years and older who were admitted to hospital with a nonpathological first hip fracture between Jan. 1, 2004, and Dec. 31, 2012, in Canada (excluding Quebec). We compared the risk of in-hospital death, overall and after surgery, between teaching hospitals and community hospitals of various bed capacities, accounting for variation in length of stay. RESULTS: Compared with the number of deaths per 1000 admissions at teaching hospitals, there were an additional 3 (95% confidence interval [CI] 1-6), 14 (95% CI 10-18) and 43 (95% CI 35-51) deaths per 1000 admissions at large, medium and small community hospitals, respectively. For the risk of in-hospital death overall, the adjusted odds ratios (ORs) were 1.05 (95% CI 0.99-1.11), 1.16 (95% CI 1.09-1.24) and 1.44 (95% CI 1.31-1.57) at large, medium and small community hospitals, respectively, compared with teaching hospitals. For the risk of postsurgical death in hospital, the adjusted ORs were 1.06 (95% CI 1.00-1.13), 1.13 (95% CI 1.04-1.23) and 1.18 (95% CI 0.87-1.60) at large, medium and small community hospitals, respectively. INTERPRETATION: Compared with teaching hospitals, the risk of in-hospital death among patients with hip fracture was higher at medium and small community hospitals, and the risk of in-hospital death after surgery was higher at medium community hospitals. No differences were found between teaching and large community hospitals. Future research should examine the role of volume, demand and bed occupancy for observed differences.

Cement Augmentation in Sacroiliac Screw Fixation Offers Modest Biomechanical Advantages in a Cadaver Model.

BACKGROUND: Sacroiliac screw fixation in elderly patients with pelvic fractures is prone to failure owing to impaired bone quality. Cement augmentation has been proposed as a possible solution, because in other anatomic areas this has been shown to reduce screw loosening. However, to our knowledge, this has not been evaluated for sacroiliac screws. QUESTIONS/PURPOSES: We investigated the potential biomechanical benefit of cement augmentation of sacroiliac screw fixation in a cadaver model of osteoporotic bone, specifically with respect to screw loosening, construct survival, and fracture-site motion. METHODS: Standardized complete sacral ala fractures with intact posterior ligaments in combination with ipsilateral upper and lower pubic rami fractures were created in osteoporotic cadaver pelves and stabilized by three fixation techniques: sacroiliac (n = 5) with sacroiliac screws in S1 and S2, cemented (n = 5) with addition of cement augmentation, and transsacral (n = 5) with a single transsacral screw in S1. A cyclic loading protocol was applied with torque (1.5 Nm) and increasing axial force (250-750 N). Screw loosening, construct survival, and sacral fracture-site motion were measured by optoelectric motion tracking. A sample-size calculation revealed five samples per group to be required to achieve a power of 0.80 to detect 50% reduction in screw loosening. RESULTS: Screw motion in relation to the sacrum during loading with 250 N/1.5 Nm was not different among the three groups (sacroiliac: 1.2 mm, range, 0.6-1.9; cemented: 0.7 mm, range, 0.5-1.3; transsacral: 1.1 mm, range, 0.6-2.3) (p = 0.940). Screw subsidence was less in the cemented group (3.0 mm, range, 1.2-3.7) compared with the sacroiliac (5.7 mm, range, 4.7-10.4) or transsacral group (5.6 mm, range, 3.8-10.5) (p = 0.031). There was no difference with the numbers available in the median number of cycles needed until failure; this was 2921 cycles (range, 2586-5450) in the cemented group, 2570 cycles (range, 2500-5107) for the sacroiliac specimens, and 2578 cycles (range, 2540-2623) in the transsacral group (p = 0.153). The cemented group absorbed more energy before failure (8.2 × 105 N*cycles; range, 6.6 × 105-22.6 × 105) compared with the transsacral group (6.5 × 105 N*cycles; range, 6.4 × 105-6.7 × 105) (p = 0.016). There was no difference with the numbers available in terms of fracture site motion (sacroiliac: 2.9 mm, range, 0.7-5.4; cemented: 1.2 mm, range, 0.6-1.9; transsacral: 2.1 mm, range, 1.2-4.8). Probability values for all between-group comparisons were greater than 0.05. CONCLUSIONS: The addition of cement to standard sacroiliac screw fixation seemed to change the mode and dynamics of failure in this cadaveric mechanical model. Although no advantages to cement were observed in terms of screw motion or cycles to failure among the different constructs, a cemented, two-screw sacroiliac screw construct resulted in less screw subsidence and greater energy absorbed to failure than an uncemented single transsacral screw. CLINICAL RELEVANCE: In osteoporotic bone, the addition of cement to sacroiliac screw fixation might improve screw anchorage. However, larger mechanical studies using these findings as pilot data should be performed before applying these preliminary findings clinically.

Sedentary Behavior and Physical Activity Patterns in Older Adults After Hip Fracture: A Call to Action.

OBJECTIVES: To characterize patterns of sedentary behavior and physical activity in older adults recovering from hip fracture and to determine characteristics associated with activity. METHODS: Community-dwelling, Canadian adults (65 years+) who sustained hip fracture wore an accelerometer at the waist for seven days and provided information on quality of life, falls self-efficacy, cognitive functioning, and mobility. RESULTS: There were 53 older adults (mean age [SD] 79.5 [7.8] years) enrolled in the study; 49 had valid data and demonstrated high levels of sedentary time (median [p10, p90] 591.3 [482.2, 707.2] minutes/day), low levels of light activity (186.6 [72.6, 293.7]), and MVPA (2 [0.1, 27.6]), as well as few daily steps (2467.7 [617.1, 6820.4]). Regression analyses showed that age, gender, gait speed, and time since fracture were associated with outcomes. CONCLUSIONS: Older adults have long periods of sedentary time with minimal activity. Results are a call to action to encourage people to sit less and move more.

A scoping review of the proximal humerus fracture literature.

BACKGROUND: Proximal humerus fractures are a common fragility fracture that significantly affects the independence of older adults. The outcomes of these fractures are frequently disappointing and previous systematic reviews are unable to guide clinical practice. Through an integrated knowledge user collaboration, we sought to map the breadth of literature available to guide the management of proximal humerus fractures. METHODS: We utilized a scoping review technique because of its novel ability to map research activity and identify knowledge gaps in fields with diverse treatments. Through multiple electronic database searches, we identified a comprehensive body of proximal humerus fracture literature that was classified into eight research themes. Meta-data from each study were abstracted and descriptive statistics were used to summarize the results. RESULTS: 1,051 studies met our inclusion criteria with the majority of research being performed in Europe (64%). The included literature consists primarily of surgical treatment studies (67%) and biomechanical fracture models (10%). Nearly half of all clinical studies are uncontrolled case series of a single treatment (48%). Non-randomized comparative studies represented 12% of the literature and only 3% of the studies were randomized controlled trials. Finally, studies with a primary outcome examining the effectiveness of non-operative treatment or using a prognostic study design were also uncommon (4% and 6%, respectively). CONCLUSIONS: The current study provides a comprehensive summary of the existing proximal humerus fracture literature using a thematic framework developed by a multi-disciplinary collaboration. Several knowledge gaps have been identified and have generated a roadmap for future research priorities.

A scoping review of biomechanical testing for proximal humerus fracture implants.

BACKGROUND: Fixation failure is a relatively common sequela of surgical management of proximal humerus fractures (PHF). The purpose of this study is to understand the current state of the literature with regard to the biomechanical testing of proximal humerus fracture implants. METHODS: A scoping review of the proximal humerus fracture literature was performed, and studies testing the mechanical properties of a PHF treatment were included in this review. Descriptive statistics were used to summarize the characteristics and methods of the included studies. RESULTS: 1,051 proximal humerus fracture studies were reviewed; 67 studies met our inclusion criteria. The most common specimen used was cadaver bone (87%), followed by sawbones (7%) and animal bones (4%). A two-part fracture pattern was tested most frequently (68%), followed by three-part (23%), and four-part (8%). Implants tested included locking plates (52%), intramedullary devices (25%), and non-locking plates (25%). Hemi-arthroplasty was tested in 5 studies (7%), with no studies using reverse total shoulder arthroplasty (RTSA) implants. Torque was the most common mode of force applied (51%), followed by axial loading (45%), and cantilever bending (34%). Substantial testing diversity was observed across all studies. CONCLUSIONS: The biomechanical literature was found to be both diverse and heterogeneous. More complex fracture patterns and RTSA implants have not been adequately tested. These gaps in the current literature will need to be addressed to ensure that future biomechanical research is clinically relevant and capable of improving the outcomes of challenging proximal humerus fracture patterns.

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.

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.