Prevalence Characteristics of Osteoporosis Fractures in the Elderly in Two Regions of China and Analysis of the Lag Effect of Air Pollutants on them.

OBJECTIVE: Air pollution is increasing and threatening human health. The objective of this study is to investigate the population distribution characteristics of elderly osteoporosis fractures in Hebei Province and Xinjiang Uygur Autonomous Region and to analyze the effects of air pollutants on the number of elderly osteoporosis fracture inpatients in the two regions. METHOD: A retrospective collection of elderly osteoporosis fracture cases was conducted in selected hospitals in Hebei Province and Xinjiang Uygur Autonomous Region from January 1, 2018 to December 31, 2022. The chi-square test was used to compare the distributional characteristics of the population in the two regions. Additionally, we used a distributed lag nonlinear model (DLNM) in order to assess the effect of air pollutants on the number of daily hospital admissions of elderly osteoporosis fracture patients in different regions. RESULT: A total of 19,203 elderly osteoporosis fracture patients were included in the study. The average age of these patients was 76.66 ± 7.55 years, and the majority of them were female (13,514 instances, 70.37%). The disparities in age distribution (χ2 = 133.9 p < 0.001), fracture site (χ2 = 62.0 p < 0.001), and hospitalization cost (Z = -15.635 p < 0.001) between the two regions were statistically significant. The lag effect curves of PM2.5, PM10, and NO2 on the number of elderly osteoporosis fracture hospitalizations in Xinjiang Uygur Autonomous Region exhibited a similar pattern resembling a "W"-shaped curve. All three pollutants reached their highest values after a lag time of 14 days (PM2.5: RR = 1.053, 95% CI: 1.031, 1.074; PM10: RR = 1.031, 95% CI: 1.018, 1.043; NO2: RR = 1.125, 95% CI: 1.070, 1.182). In Hebei Province, the largest impacts of PM2.5 and PM10 were observed after a lag of 14 days (PM2.5: RR = 1.022, 95% CI: 1.013, 1.028; PM10: RR = 1.013, 95% CI: 1.008, 1.018). Similarly, the maximum effect of NO2 was observed after a lag of 11 days (RR = 1.020, 95% CI: 1.010, 1.028). CONCLUSION: There were differences in the epidemiological characteristics of hospitalized patients with osteoporosis fractures between the two regions, PM2.5, PM10, and NO2 increased the number of hospitalizations for osteoporosis fractures. Exposure to air pollutants such as PM2.5 increases the risk of osteoporosis fractures in the elderly population.

Biomechanical optimization of the magnesium alloy bionic cannulated screw for stabilizing femoral neck fractures: a finite element analysis.

Purposes: The magnesium alloy bionic cannulated screw (MABCS) was designed in a previous study promoting cortical-cancellous biphasic healing of femoral neck fractures. The main purpose was to analyze the bore diameters that satisfy the torsion standards and further analyze the optimal pore and implantation direction for stabilizing femoral neck fractures. Methods: The MABCS design with bionic holes with a screw diameter of less than 20% met the torsion standard for metal screws. The MABCS was utilized to repair the femoral neck fracture via Abaqus 6.14 software, which simulated the various stages of fracture healing to identify the optimal biomechanical environment for bionic hole size (5%, 10%, 15%, and 20%) and implantation direction (0°, 45°, 90°, and 135°). Results: The stress distribution of the MABCS fracture fixation model is significantly improved with an implantation orientation of 90°. The MABCS with a bionic hole and a screw diameter of 10% provides optimal stress distribution compared with the bionic cannulated screw with diameters of 5%, 15%, and 20%. In addition, the cannulated screw fixation model with a 10% bionic hole size has optimal bone stress distribution and better internal fixation than the MABCS fixation models with 5%, 15%, and 20% screw diameters. Conclusion: In summary, the MABCS with 10% screw diameter bionic holes has favorable biomechanical characteristics for stabilizing femoral neck fractures. This study provides a biomechanical foundation for further optimization of the bionic cannulated screw.

Duration of surgical antibiotic prophylaxis and surgical site infection in orthopaedic surgery: A prospective cohort study.

BACKGROUND: The optimal duration for surgical antibiotic prophylaxis (SAP) for preventing surgical site infection (SSI) in orthopaedic surgeries remains poorly supported by high-level evidence. This study aimed to assess the association between SAP duration and the occurrence of SSI within one year postoperatively. METHODS: This prospective cohort study was based on the database from Surgical Site Infection Surveillance and Improvement Project (SISIP) of a tertiary orthopaedic university hospital from October 2014 to December 2020. The main outcome was SSI, defined according to the CDC/NHSN criteria, determined by review of index hospitalization medical records, microbiology laboratory reports, and readmission records for SSI treatment within one-year after discharge. Adjusted Generalized additive models (GAMs) were performed to assess the relationships between SAP duration and SSI, determined the cut-off point of SAP duration, and estimate the relative contribution of each included variable, across the overall cohort and the three subgroups (open fracture, closed fracture, and non-traumatic group). Multivariable logistic regression models were used to estimate the association between prolonging SAP duration based on the cut-off point and SSI. RESULTS: There were 37,046 patients (55.1% male) included, with the overall SSI incidence of 2.35% (871/37,046). In adjusted GAMs, no statistically significant relationships were observed in overall cohort and open or closed group (P>0.05), but a nonlinear relationship was exhibited non-traumatic group (P=0.03); the cut-off point were 2.4 days for overall cohort and 3.6 days (open), 2.6 days (closed), 1.1 days (non-trauma) for three subgroups. In adjusted logistic regression, prolonging SAP duration did not demonstrate a statistically significant protective effect in overall cohort (aOR=0.868; 95% CI, 0.746-1.011) and three groups (open: aOR=0.867; 95% CI, 0.668-1.124; closed: aOR=0.925; 95% CI, 0.754-1.135; non-trauma: aOR=1.184; 95% CI, 0.832-1.683). The relative contribution ranks of SAP duration were 21st overall among 34 factors, 14th for open fractures, 28th for closed fractures, and 3rd for non-traumatic group among 33 factors. CONCLUSION: Prolonged postoperative SAP duration has no protective effect against SSI in orthopaedic surgery. Our findings support current guidelines against the practice of continuing SAP postoperatively.

Corrigendum: Prediction model for tibial plateau fracture combined with meniscus injury.

[This corrects the article DOI: 10.3389/fsurg.2023.1095961.].

Development and validation of predictive nomogram for postoperative non-union of closed femoral shaft fracture.

Closed femoral shaft fracture is caused by high-energy injuries, and non-union exists after operation, which can significantly damage patients' body and mind. This study aimed to explore the factors influencing postoperative non-union of closed femoral shaft fractures and establish a predictive nomogram. Patients with closed femoral shaft fractures treated at Hebei Medical University Third Hospital between January 2015 and December 2021 were retrospectively enrolled. A total of 729 patients met the inclusion criteria; of them, those treated in 2015-2019 comprised the training cohort (n = 617), while those treated in 2020-2021 comprised the external validation cohort (n = 112). According to multivariate logistic regression analysis, complex fractures, bone defects, smoking, and postoperative infection were independent risk factors. Based on the factors, a predictive nomogram was constructed and validated. The C-indices in training and external validation cohorts were 0.818 and 0.781, respectively; and the C-index of internal validation via bootstrap resampling was 0.804. The Hosmer-Lemeshow test showed good fit of the nomogram (P > 0.05) consistent with the calibration plot results. The clinical effectiveness was best at a threshold probability of 0.10-0.40 in decision curve analysis. The risk prediction for patients with fractures using this nomogram may aid targeted prevention and rehabilitation programs.

The Different Therapeutic Effects of Traditional Chinese Medicine Shensong Yangxin Capsule and Salubrinal in High-intensity Exercise-induced Heart Failure in Rats with Acute Myocardial Infarction.

BACKGROUND: Currently, endoplasmic reticulum stress is studied utilizing a dephosphorylation inhibitor (Sal). The traditional Chinese patent medicine and simple formulation Shensong Yangxin Capsule is a commonly used medication for the treatment of arrhythmia. However, the efficacy and underlying mechanism of the capsule in treating post-ischemic heart failure in myocardial tissue have not yet been investigated. OBJECTIVE: The therapeutic effects and the underlying mechanism of the Shensong Yangxin Capsule (SSYX) and the dephosphorylation inhibitor Salubrinal (Sal) on heart failure (HF) induced by high-intensity exercise in rats with acute myocardial infarction (AMI) were investigated. METHODS: Male infants of 8 weeks Spragge-Dawley (SD) rats were randomly assigned to one of four groups: sham surgery group, AMI+placebo group, AMI+Shensong Yangxin Capsule group (AMI+SSYX), and AMI+Sal administration group. Rats' myocardial infarction was induced by left coronary artery ligation. Rats were subjected to a 3-week high-intensity exercise program to simulate heart failure after 7 days of postoperative rest. After the fourth postoperative week, echocardiography was applied to determine the left ventricular ejection fraction (LVEF), left ventricular fractional shortening (LVFS), and left ventricular systolic volume (LVESV) in each group. HE and TUNEL labeling were employed to examine the morphology of cardiac cells and measure the percentage of apoptosis in each group; Western blotting was applied to detect the cardiomyocyte apoptosis-related proteins p-JNK, p-P38, and NOX2, while ELISA was used to detect glutathione(GSH), malondialdehyde (MDA), and superoxide dismutase (SOD) in serum. RESULTS: Following a 4-week drug intervention:(1)LVFS and LVEF in the AMI+placebo group were statistically significantly reduced, while LVESV were significantly higher, compared to those in the sham surgery group (P<0.05); The AMI+SSYX group performed statistically significantly better than the AMI+placebo group(P<0.05). (2) The myocardial cells in the AMI+placebo group exhibited significant swelling and inflammatory cell infiltration; the myocardial cells in the AMI+SSYX group and AMI+Sal group displayed mild swelling and minimal inflammatory cell infiltration; the AMI+SSYX group's myocardial cell morphology was superior to that of the AMI+Sal group; (3) The apoptosis rate of the AMI+placebo group was around 95%, greater than that of the sham surgery group (2.55%). The apoptosis rate of the AMI+SSYX group is approximately 21%, while the apoptosis rate of the AMI+Sal group is about 43%. (4) In the AMI+placebo group, p-JNK, p-P38, and NOX2 protein expression dramatically increased compared to the sham surgery group. The expression of p-P38, NOX2, and p-JNK/t-JNK was considerably reduced in the AMI+Shensong group and AMI+Sal group, compared to the AMI+placebo group. (P<0.01)The AMI+SSYX group's result is superior to that of the AMI+Sal group. (5) Compared to the sham surgery group, the serum levels of SOD and GSH were significantly lower, and MDA was significantly higher in the AMI+placebo group. Compared to the AMI+placebo group, the serum levels of SOD and GSH were significantly higher, and MDA was significantly lower in the AMI+SSYX group and the AMI+Sal group. (P<0.05) Conclusion: In rats with acute myocardial infarction in high-intensity exercise-induced heart failure, Shensong Yangxin Capsule dramatically reduces myocardial cell death and cardiac dysfunction. SSYX has a shorter course of treatment and a better therapeutic effect than Sal.

Correction: Zhu et al. Mineralized Collagen/Polylactic Acid Composite Scaffolds for Load-Bearing Bone Regeneration in a Developmental Model. Polymers 2023, 15, 4194.

In the original publication [...].

Reference intervals of biochemical analytes in healthy adults from northern China: A population-based cross-sectional study.

Reference intervals (RIs) of laboratory testing play a fundamental role in medical activities. RIs vary greatly for populations in different areas This study aimed to evaluate the age- and sex-specific reference intervals for a healthy population in a typical city of northern China. A cross-sectional study was performed in 4 tertiary care centers of Shijiazhuang of China, biochemical analytes were analyzed using a Beckman Coulter AU5800 (Beckman Coulter Inc., Brea, CA). A total of 42,979 healthy individuals were involved in this study. Grouped by age- and sex-specific, reference intervals of all the measures have been established. We found that different age groups of males and females have significant differences (all P < .001) in levels of various biochemical analytes. We provided a comprehensive age- and sex-specific RIs for biochemical analytes, which showed dynamic changes with both age and sex. For the local population, the reference intervals established here can be adopted in other clinical laboratories after appropriate validation.

Mineralized Collagen/Polylactic Acid Composite Scaffolds for Load-Bearing Bone Regeneration in a Developmental Model.

Repairing load-bearing bone defects in children remains a big clinical challenge. Mineralized collagen (MC) can effectively simulate natural bone composition and hierarchical structure and has a good biocompatibility and bone conductivity. Polylactic acid (PLA) is regarded as a gold material because of its mechanical properties and degradability. In this study, we prepare MC/PLA composite scaffolds via in situ mineralization and freeze-drying. Cell, characterization, and animal experiments compare and evaluate the biomimetic properties and repair effects of the MC/PLA scaffolds. Phalloidin and DAPI staining results show that the MC/PLA scaffolds are not cytotoxic. CCK-8 and scratch experiments prove that the scaffolds are superior to MC and hydroxyapatite (HA)/PLA scaffolds in promoting cell proliferation and migration. The surface and interior of the MC/PLA scaffolds exhibit rich interconnected pore structures with a porosity of ≥70%. The XRD patterns are typical HA waveforms. X-ray, micro-CT, and H&E staining reveal that the defect boundary disappears, new bone tissue grows into MC/PLA scaffolds in a large area, and the scaffolds are degraded after six months of implantation. The MC/PLA composite scaffold has a pore structure and composition similar to cancellous bone, with a good biocompatibility and bone regeneration ability.

A risk prediction model for postoperative recovery of closed calcaneal fracture: a retrospective study.

OBJECTIVE: To explore the risk factors for postoperative recovery of closed calcaneal fracture and develop a prediction model. METHODS: We retrospectively enrolled patients with closed calcaneal fracture from January 1, 2017 to December 31, 2020. Patients treated from 2017 to 2019 were selected as a training cohort and those in 2020 as a validation cohort. The outcome variable was the postoperative recovery evaluated by the Creighton-Nebraska calcaneal fracture scoring system. Multivariate logistic regression analysis was used to screen the risk factors of postoperative recovery. A risk prediction model was constructed in the training cohort and the corresponding nomogram was drawn. The model was validated internally using bootstrapping and externally by calculating the performance in the validation cohort. RESULTS: A total of 659 patients with closed calcaneal fracture met the inclusion and exclusion criteria, which were divided into the training cohort (n = 509) and the validation cohort (n = 150). 540 cases (81.9%) patients recovered well after calcaneal fracture surgery. According to multivariate logistic regression analysis, female (OR = 2.525, 95% CI 1.283-4.969), > 60 years (OR = 6.644, 95% CI 1.243-35.522), surgery within 8-14 days after fracture (OR = 2.172, 95% CI 1.259-3.745), postoperative infection (OR = 4.613, 95% CI 1.382-15.393), and weight-bearing time longer than 3 months after surgery (4-6 months, OR = 2.885, 95% CI 1.696-4.907; 7-12 months, OR = 3.030, 95% CI 1.212-7.578; > 12 months, OR = 15.589, 95% CI 3.244-74.912) were independent risk factors for postoperative recovery of calcaneal fractures. The C-indices were 0.750(95% CI 0.692-0.808) in the training cohort and 0.688(95% CI 0.571-0.804) in the external validation cohort, and the C-index of internal validation was 0.715. The Hosmer-Lemeshow test showed good fitting of the model (all P > 0.05), which was consistent with the results of the calibration plots. Decision Curve Analysis indicated that the clinical effectiveness was the best when the threshold probability was between 0.10 and 0.45. CONCLUSIONS: Patients with female, > 60 years, surgery within 8-14 days after fracture, postoperative infection, and weight-bearing time longer than 3 months after surgery are more likely to have poor postoperative recovery. The risk prediction of fracture patients through this model might be translated into clinical guidance and application. Trial registration This study was registered on the Chinese Clinical Trial Registry (Registration number: ChiCTR-EPR-15005878).

Advances in the Study of Bionic Mineralized Collagen, PLGA, Magnesium Ionomer Materials, and Their Composite Scaffolds for Bone Defect Treatment.

The healing of bone defects after a fracture remains a key issue to be addressed. Globally, more than 20 million patients experience bone defects annually. Among all artificial bone repair materials that can aid healing, implantable scaffolds made from a mineralized collagen (MC) base have the strongest bionic properties. The MC/PLGA scaffold, created by adding Poly (lactic-co-glycolic acid) copolymer (PLGA) and magnesium metal to the MC substrate, plays a powerful role in promoting fracture healing because, on the one hand, it has good biocompatibility similar to that of MC; on the other hand, the addition of PLGA provides the scaffold with an interconnected porous structure, and the addition of magnesium allows the scaffold to perform anti-inflammatory, osteogenic, and angiogenic activities. Using the latest 3D printing technology for scaffold fabrication, it is possible to model the scaffold in advance according to the requirement and produce a therapeutic scaffold suitable for various bone-defect shapes with less time and effort, which can promote bone tissue healing and regeneration to the maximum extent. This study reviews the material selection and technical preparation of MC/PLGA scaffolds, and the progress of their research on bone defect treatment.

Prediction model for tibial plateau fracture combined with meniscus injury.

Purpose: To investigate a prediction model of meniscus injury in patients with tibial plateau fracture. Methods: This retrospective study enrolled patients with tibial plateau fractures who were treated in the Third Hospital of Hebei Medical University from January 1, 2015, to June 30, 2022. Patients were divided into a development cohort and a validation cohort based on the time-lapse validation method. Patients in each cohort were divided into a group with meniscus injury and a group without meniscus injury. Statistical analysis with Student's t-test for continuous variables and chi square test for categorical variables was performed for patients with and without meniscus injury in the development cohort. Multivariate logistic regression analysis was used to screen the risk factors of tibial plateau combined with meniscal injury, and a clinical prediction model was constructed. Model performance was measured by examining discrimination (Harrell's C-index), calibration (calibration plots), and utility [decision analysis curves (DCA)]. The model was validated internally using bootstrapping and externally by calculating their performance in a validation cohort. Results: Five hundred patients (313 [62.6%] males, 187 [37.4%] females) with a mean age of 47.7 ± 13.8 years were eligible and were divided into development (n = 262) and validation (n = 238) cohorts. A total of 284 patients had meniscus injury, including 136 in the development cohort and 148 in the validation cohort We identified high-energy injuries as a risk factor (OR = 1.969, 95%CI 1.131-3.427). Compared with blood type A, patients with blood type B were more likely to experience tibial plateau fracture with meniscus injury (OR = 2.967, 95%CI 1.531-5.748), and office work was a protective factor (OR = 0.279, 95%CI 0.126-0.618). The C-index of the overall survival model was 0.687 (95% CI, 0.623-0.751). Similar C-indices were obtained for external validation [0.700(0.631-0.768)] and internal validation [0.639 (0.638-0.643)]. The model was adequately calibrated and its predictions correlated with the observed outcomes. The DCA curve showed that the model had the best clinical validity when the threshold probability was 0.40 and 0.82. Conclusions: Patients with blood type B and high-energy injuries are more likely to have meniscal injury. This may help in clinical trial design and individual clinical decision-making.

Advances in osseointegration of biomimetic mineralized collagen and inorganic metal elements of natural bone for bone repair.

At this stage, bone defects caused by trauma, infection, tumor, or congenital diseases are generally filled with autologous bone or allogeneic bone transplantation, but this treatment method has limited sources, potential disease transmission and other problems. Ideal bone-graft materials remain continuously explored, and bone defect reconstruction remains a significant challenge. Mineralized collagen prepared by bionic mineralization combining organic polymer collagen with inorganic mineral calcium phosphate can effectively imitate the composition and hierarchical structure of natural bone and has good application value in bone repair materials. Magnesium, strontium, zinc and other inorganic components not only can activate relevant signaling pathways to induce differentiation of osteogenic precursor cells but also stimulate other core biological processes of bone tissue growth and play an important role in natural bone growth, and bone repair and reconstruction. This study reviewed the advances in hydroxyapatite/collagen composite scaffolds and osseointegration with natural bone inorganic components, such as magnesium, strontium and zinc.

Proximal tibia osteotomy with absorbable spacer combined with fibular osteotomy versus high tibial osteotomy for medial compartmental knee osteoarthritis.

PURPOSE: The study aimed to compare the perioperative complications, short-term clinical outcomes, patient-reported outcomes, and radiographic parameters of tibiofibular proximal osteotomy combined with absorbable spacer insertion (TPOASI) and open-wedge high tibial osteotomy (OWHTO) in a two year postoperative time period. METHODS: A total of 160 patients with Kellgren-Lawrence classification grade 3 medial compartmental knee OA were randomized to receive either TPOASI (n = 82) or OWHTO (n = 78). The primary and secondary outcomes were measured preoperatively, postoperatively, and at each follow-up examination. The primary outcomes were the between-group change in the Western Ontario and McMaster Universities Global score (WOMAC). Secondary measures included visual analog scale (VAS), radiographic parameters, American Knee Society Score (KSS), operation time, blood loss, length of incision, hospital stay, and relevant complications. Postoperative radiographic parameters, including the femorotibial angle (FTA), varus angle (VA), and joint line convergence angle (JLCA), were measured to evaluate the correction of varus deformity. RESULTS: No significant differences were found in the baseline data between the two groups. Both methods improved functional status and pain postoperatively. For primary outcomes of both groups, statistical difference was observed in WOMAC scores at the 6-month follow-up (P < 0.001). For secondary outcomes, no statistical difference was observed between the groups during the 2-year follow-up (P > 0.05). For TPOASI vs. OWHTO, the mean hospital stay (6.6 ± 1.3 days vs. 7.8 ± 2.1 days) was shorter (P < 0.001), and both blood loss (70.56 ± 35.58 vs. 174.00 ± 66.33 mL) and complication rate (3.7% vs. 12.8%) were significantly lower (P < 0.005 for both). CONCLUSIONS: Both approaches showed satisfactory functional outcomes and alleviated pain. However, TPOASI is a simple, feasible method with few complications, and it could be widely used.

Corrigendum to "Biologically modified implantation as therapeutic bioabsorbable materials for bone defect repair" [Regen Ther 19 (2022) 9-23].

[This corrects the article DOI: 10.1016/j.reth.2021.12.004.].

Patellofemoral Joint after Opening Wedge High Tibial Osteotomy: A Comparative Study of Uniplane versus Biplane Osteotomies.

OBJECTIVE: To the best of our knowledge, there has been no comparative study of changes in radiographic parameters in the sagittal plane between biplane opening wedge high tibial osteotomy (OWHTO) with plate fixation and uniplane OWHTO with spacer implantation. The aim of the study was to compare sagittal radiographs between the procedures of biplane and uniplane OWHTOs in patients with genu varum and to investigate the impact on the patellofemoral joint. METHODS: A retrospective study of 71 patients (58.0 ± 5.0 years of age, 58 females and 13 males) with varus-aligned medial compartment knee osteoarthritis treated with OWHTO was performed during the period from January 2016 to February 2019. Thirty-three patients underwent biplane osteotomy with plate fixation (biplane group), and 38 patients underwent uniplane osteotomy with absorbable wedged spacer fixation (uniplane group). Independent t tests were used to compare the two groups according to the preoperative and postoperative radiographic parameters of hip-knee-ankle (HKA) angle, posterior tibial slope (PTS), tibial tubercle prominence (TTP), Caton-Deschamps (CD) index, and Blackburne-Peel (BP) index. During the last follow-up assessment, patients were asked to rate their patellofemoral joint status using the Samsung Medical Center (SMC) patellofemoral (PF) scoring system. The visual analog scale (VAS) was also used to rate knee joint pain when walking. RESULTS: There was no significant difference between the two groups in any of the demographic, clinical, or radiological characteristics at baseline (p > 0.05). Comparisons of postoperative sagittal radiographic parameters between patients in the uniplane group and patients in the biplane group showed significant differences in the PTS (13.4° vs 16.6°, t = 4.465, p < 0.001), TTP (9.0 mm vs 4.2 mm, t = 7.950, p < 0.001), and CD index (0.81 vs 0.70, t = 4.035, p < 0.001). At the final follow-up assessment (minimum, 2 years), the SMC PF function score was significantly lower in patients in the uniplane group than in patients in the biplane group (27.8 vs. 32.1, t = 2.458, p = 0.016), but there were no significant differences in the SMC PF pain score or VAS score (p > 0.05). CONCLUSION: The essential difference in the postoperative sagittal radiographic changes between biplane and uniplane OWHTO was the tibial tubercle prominence, indicating the posterior displacement of the tibial tubercle. Uniplane OWHTO may yield better function of the patellofemoral joint compared to biplane OWHTO.

National incidence of joint dislocation in China: a retrospective survey of 512,187 individuals.

BACKGROUND: Joint dislocations significantly impact public health. However, a comprehensive study on the incidence, distribution, and risk factors for joint dislocations in China is lacking. We conducted the China National Joint Dislocation Study, which is a part of the China National Fracture Study conducted to obtain the national incidence and risk factors for traumatic fractures, and to investigate the incidence and risk factors for joint dislocations. METHODS: For this national retrospective epidemiological study, 512,187 participants were recruited using stratified random sampling and probability-proportional-to-size method from January 19 to May 16, 2015. Participants who sustained joint dislocations of the trunk, arms, or legs (skull, sternum, and ribs being excluded) in 2014 were personally interviewed to obtain data on age, educational background, ethnic origin, occupation, geographic region, and urbanization degree. The joint-dislocation incidence was calculated based on age, sex, body site, and demographic factors. The risk factors for different groups were examined using multiple logistic regression. RESULTS: One hundred and nineteen participants sustained 121 joint dislocations in 2014. The population-weighted incidence rate of joint dislocations of the trunk, arms, or legs was 0.22 (95% confidence interval [CI]: 0.16, 0.27) per 1000 population in 2014 (men, 0.27 [0.20, 0.34]; women, 0.16 [0.10, 0.23]). For all ages, previous dislocation history (male: OR 42.33, 95% confidence interval [CI]: 12.03-148.90; female: OR 54.43, 95% CI: 17.37-170.50) and alcohol consumption (male: OR 3.50, 95% CI: 1.49-8.22; female: OR 2.65, 95% CI: 1.08-6.50) were risk factors for joint dislocation. Sleeping less than 7 h/day was a risk factor for men. Compared with children, women aged ≥15 years (female 15-64 years: OR 0.16, 95% CI: 0.04-0.61; female ≥65 years: OR 0.06, 95% CI: 0.01-0.41) were less likely to sustain joint dislocations. Women with more than three children were at higher dislocation risk than women without children (OR 6.92, 95% CI: 1.18-40.78). CONCLUSIONS: The up-to-date data on joint dislocation incidence, distribution, and risk factors can be used as a reference for national healthcare, prevention, and management in China. Specific strategies for decreasing alcohol consumption and encouraging adequate sleeping hours should be developed to prevent or reduce dislocation incidents. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR-EPR-15005878.

Epidemiological characteristics of fractures of spine, hip, proximal humerus and forearm during the haze epidemic period.

BACKGROUND: Air pollutants have an impact on the occurrence of spine fractures, hip fractures, proximal humerus fractures and forearm fractures. This study aimed at evaluating the short-term impact of particulate matter with aerodynamic diameters of less than 2.5 µm (PM2.5) on the occurrence of those fractures in Shijiazhuang, Hebei, China. METHODS: The daily meteorological, pollution, and fracture data of Shijiazhuang from 2014 to 2019 were collected. Distribution characteristics of fractures were described using descriptive epidemiological methods. The distributed lag nonlinear model (DLNM) was used to reveal the description of those fractures in the exposed and lag dimensions at the same time. Based on gender and age (<18 years old, 18-69 years old and >69 years old), stratified analysis was performed. Sensitivity analysis was performed to ascertain the robustness of the results. RESULTS: Between 2014 and 2019, fracture incidences in Shijiazhuang exhibited an overall increasing trend, with an obvious seasonality. PM2.5 was positively related to daily fracture cases and the effects were more obvious in women, adolescents and people of working age. When PM2.5 concentrations increased by one interquartile range (IQR) (70 µg/m3), RR exhibited a unimodal distribution. Its peak appeared on the 16th day of lag (RR=1.005987, 95% CI:1.002472,1.009652), and the RRs were also statistically significant from the 10th to 22nd day of lag. Similarly, cumulative effects of each increase in the concentration of PM2.5 IQR also showed a unimodal distribution. The largest cumulative effect occurred on the 28th day of lag (RR=1.084457, 95% CI:1.012207,1.161864), and the cumulative RRs were also statistically significant from the 19th day to 30nd days. In the dose-response relationship, as PM2.5 concentrations increased, RR increased. CONCLUSION: Year by year, fractures in Shijiazhuang City exhibited an increasing trend. PM2.5 can affect the occurrence of those fractures. The impact on women, adolescents and people of working age is even greater. The supervision of PM2.5 should be strengthened while large-scale emissions should be limited.

Short-term effects of COVID-19 on the risk of traumatic fractures in China cities.

This study aimed to investigate the association between COVID-19 and fracture risk and provide a targeted reference for the world through China's experience. A nationally representative sample of COVID-19 prevalence areas selected using stratified random sampling was retrospectively analyzed. Age, sex, fracture site, mechanism of injury, and concurrent fractures of traumatic fracture patients in selected hospitals were collected from 10 January to 10 July 2020. The epidemiologic characteristics of traumatic fractures and the association between COVID-19 and fracture risk were explored using descriptive epidemiological methods and a distributed lag nonlinear model. A total of 67,249 patients (52.3% males, 49.4 ± 19.4 years old) with 68,989 fractures were included. The highest proportion of fractures were in the tibia and fibula (14.9%), followed by the femur (13.6%) and ulna and radius (12.5%). Low-energy fractures accounted for 23.3%. With the increase in newly confirmed COVID-19 cases, fracture risk decreased for children, young and middle-aged adults, elderly men, high-energy fractures, and residents in regions with < 1000 cumulative confirmed COVID-19 cases. Fracture risk decreased sharply in all residents except elderly women, for low-energy fractures, and in regions with > 1000 cumulative confirmed COVID-19 cases when newly confirmed COVID-19 cases increased in China. Primary (home) prevention measures are emphasized to prevent traumatic fractures.