BACKGROUND:The sports medicine community has widely called for the use of machine learning technology to efficiently process the huge and complicated sports data resources,and construct intelligent sports injury prediction models,enabling accurate early warning of sports injuries.It is of great significance to comprehensively summarize and review such research results so as to grasp the direction of early warning model improvement and to guide the construction of sports injury prediction models in China. OBJECTIVE:To systematically review and analyze relevant research on sports injury prediction models based on machine learning technology,thereby providing references for the development of sports injury prediction models in China. METHODS:Literature search was conducted on CNKI,Web of Science and EBSCO databases,which mainly searched for literature related to machine learning techniques and sports injuries.Finally,61 articles related to sports injury prediction models were included for analysis. RESULTS AND CONCLUSION:(1)In terms of external risk feature indicators,there is a lack of competition scenario indicators,and the inclusion of related feature indicators needs to be further improved to further enrich the dimensions of the dataset for model training.In addition,the inclusion feature weighting methods of the sports injury prediction model are mainly based on filtering methods and the use of embedding and wrapping weighting methods needs to be strengthened in order to enhance the analysis of the interaction effects of multiple risk factors.(2)In terms of model body training,supervised learning algorithms become the mainstream choice.Such algorithms have higher requirements for the completeness of sample labeling information,and the application scenarios are easily limited.Therefore,the application of unsupervised and semi-supervised algorithms can be increased in the later stage.(3)In terms of model performance evaluation and optimization,the current studies mainly adopt two verification methods:HoldOut crossover and k-crossover.The range of AUC values is(0.76±0.12),the range of sensitivity is(75.92±11.03)%,the range of specificity is(0.03±4.54)%,the range of F1 score is(80.60±10.63)%,the range of accuracy is(69.96±13.10)%,and the range of precision is(70±14.71)%.Data augmentation and feature optimization are the most common model optimization operations.The accuracy and precision of the current sports injury prediction model are about 70%,and the early warning effect is good.However,the model optimization operation is relatively single,and data augmentation methods are often used to improve model performance.Further adjustments to the model algorithm and hyperparameters are needed to further improve model performance.(4)In terms of model feature extraction,most of the internal risk profile indicators included are mainly based on anthropometrics,training load,years of training,and injury history,but there is a lack of sports recovery and physical function indicators.

Objective: To investigate the occupational health status of medical radiation workers in Hangzhou City, so as to provide the basis for their occupational health risk assessment. Methods: Data on medical radiological workers who underwent occupational health examinations from 2021 to 2022 were collected through the Physical Examination Information Management System of the Hangzhou Occupational Disease Prevention and Control Hospital. The physical examination data including blood routine, eye lens, thyroid ultrasound, thyroid function, liver function, renal function and blood lipid were collected, and the abnormal rates of occupational health examinations among workers with different genders, working years and occupational exposure types were analyzed. Results: A total of 3 968 medical radiation workers were investigated, including 2 310 males (58.22%) and 1 658 females (41.78%). There were 2 039 (51.39%), 821 (20.69%) and 1 108 (27.92%) workers with 1-<6, 6-<10 years and 10 years and above of work, respectively. Diagnostic radiology was the predomenant type of exposure, with 2 240 workers accounting for 56.45%. The abnormal rates of thyroid ultrasound and blood lipid were 47.73% and 45.21%, respectively, which were relatively higher than other items. The abnormal rates of micronucleus rate, thyroid ultrasound, thyroid function and renal function were higher in females than in males, while the abnormal rates of lymphocyte count, liver function and blood lipid in males were higher in males than in females (all P<0.05). With the increase of working years, the abnormal rates of micronucleus rate and blood lipid showed upward trends (both P<0.05). There were statistically significant differences in the abnormal rates of thyroid ultrasound, liver function and blood lipid among different occupational exposure types (all P<0.05). Conclusion Long-term low-dose ionizing radiation environment affects the thyroid, micronucleus rate and blood lipid of medical radiation workers in Hangzhou City, with differences observed among workers with different genders and occupational exposure types.

Objective: To analyze the change trends in the body shape indicators and proportions of students in Harbin from 2010 to 2024, and to investigate ergonomic compatibility of functional dimensions of school desks and chairs with current student shape indicators, so as to provide a reference for revising furniture standards of desks and chairs. Methods: Between September and November of both 2010 and 2024, a combination of convenience sampling and stratified cluster random sampling was conducted across three districts in Harbin, yielding samples of 6 590 and 6 252 students, respectively. Anthropometric shape indicators cluding height, sitting height, crus length, and thigh length-and their proportional changes were compared over the 15-year period. The 2024 data were compared with current standard functional dimensions of school furniture. The statistical analysis incorporated t-test and Mann-Whitney U- test. Results: From 2010 to 2024, average height increased by 1.8 cm for boys and 1.5 cm for girls; sitting height increased by 1.5 cm for both genders; crus length increased by 0.3 cm for boys and 0.4 cm for girls; and thigh length increased by 0.5 cm for both genders. The ratios of sitting height to height, and sitting height to leg length increased by less than 0.1 . The difference between desk chair height and 1/3 sitting height ranged from 0.4-0.8 cm. Among students matched with size 0 desks and chairs, 22.0% had a desk to chair height difference less than 0, indicating that the desk to chair height difference might be insufficient for taller students. The differences between seat height and fibular height ranged from -1.4 to 1.1 cm; and the differences between seat depth and buttock popliteal length ranged from -9.8 to 3.4 cm. Among obese students, the differences between seat width and 1/2 hip circumference ranged from -20.5 to -8.7 cm, while it ranged from -12.2 to -3.8 cm among non obese students. Conclusion Current furniture standards basically satisfy hygienic requirements; however, in the case of exceptionally tall and obese students, ergonomic accommodations such as adaptive seating allocation or personalized adjustments are recommended to meet hygienic requirements.

Background::Carotid intima-media thickness (IMT) and diameter, stiffness, and wave reflections, are independent and important clinical biomarkers and risk predictors for cardiovascular diseases. The purpose of the present study was to establish nationwide reference values of carotid properties for healthy Chinese adults and to explore potential clinical determinants.Methods::A total of 3053 healthy Han Chinese adults (1922 women) aged 18-79 years were enrolled at 28 collaborating tertiary centers throughout China between April 2021 and July 2022. The real-time tracking of common carotid artery walls was achieved by the radio frequency (RF) ultrasound system. The IMT, diameter, compliance coefficient, β stiffness, local pulse wave velocity (PWV), local systolic blood pressure, augmented pressure (AP), and augmentation index (AIx) were then automatically measured and reported. Data were stratified by age groups and sex. The relationships between age and carotid property parameters were analyzed by Jonckheere-Terpstra test and simple linear regressions. The major clinical determinants of carotid properties were identified by Pearson’s correlation, multiple linear regression, and analyses of covariance.Results::All the parameters of carotid properties demonstrated significantly age-related trajectories. Women showed thinner IMT, smaller carotid diameter, larger AP, and AIx than men. The β stiffness and PWV were significantly higher in men than women before forties, but the differences reversed after that. The increase rate of carotid IMT (5.5 μm/year in women and 5.8 μm/year in men) and diameter (0.03 mm/year in both men and women) were similar between men and women. For the stiffness and wave reflections, women showed significantly larger age-related variations than men as demonstrated by steeper regression slopes (all P for age by sex interaction <0.05). The blood pressures, body mass index (BMI), and triglyceride levels were identified as major clinical determinants of carotid properties with adjustment of age and sex. Conclusions::The age- and sex-specific reference values of carotid properties measured by RF ultrasound for healthy Chinese adults were established. The blood pressures, BMI, and triglyceride levels should be considered for clinical application of corresponding reference values.

Objective To investigate the effect of Polyetheretherketone(PEEK)rod semi-rigid pedicle screw fixation sys-tem in lumbar spine non-fusion surgery.Methods A total of 74 patients with tow-level lumbar degenerative diseases who un-derwent surgery from March 2017 to December 2019 were divided into PEEK rod group and titanium rod group.In the PEEK rod group,there were 34 patients,including 13 males and 21 females,aged from 51 to 79 years old with an average of(62.4±6.8)years old;There were 1 patient of L1-L3 segments,7 patients of L2-L4 segments,20 patients of L3-L5 segments and 6 pa-tients of L4-S1 segments.In the titanium rod group,there were 40 patients,including 17 males and 23 females,aged from 52 to 81 years old with an average of(65.2±7.3)years old;There were 3 patient of L1-L3 segments,11 patients of L2-L4 segments,19 patients of L3-L5 segments and 7 patients of L4-S1 segments.The general conditions of operation,such as operation time,intraoperative blood loss,postoperative drainage was recorded.The visual analogue scale(VAS)for low back pain and Os-westry disability index(ODI)were compared in preoperatively and postoperatively(3 months,12 months and last follow-up)between two groups.The change of range of motion(ROM)was observed by flexion and extension x-ray of lumbar Results All patients successfully completed the operation.The follow-up time ranged from 22 to 34 months with an average of(26.8±5.6)months.The operative time(142.2±44.7)min and intraoperative blood loss(166.5±67.4)ml in PEEK group were lower than those in titanium group[(160.7±57.3)min、(212.8±85.4)ml](P＜0.05).There was no significant differences in postoperative drainage between the two groups(P＞0.05).At the final follow-up visit,in PEEK group and titanium group VAS of low back pain[(0.8±0.4)points vs(1.0±0.5)points],VAS for leg pain[(0.7±0.4)points vs(0.8±0.5)points]and ODI[(9.8±1.6)％vs(12.1±1.5)％]were compared with preoperative[(5.8±1.1)points vs(6.0±1.1)points],[(7.2±1.7)points vs(7.0±1.6)points],[(68.5±8.9)％vs(66.3±8.2)％]were significantly different(P＜0.05).There was no significant difference in VAS scores between the two groups at each postoperative time point(P＞0.05).At 3 months after surgery,there was no difference in ODI between the two groups(P＞0.05).There were significant differences in ODI between PEEK group and titanium rod group at 12 months[(15.5±2.1)％vs(18.4±2.4)％]and at the last follow-up[(9.8±1.6)％vs(12.1±1.5)％](P＜0.05).The total range of motion(ROM)of lumbar decreased in both groups after surgery.At 12 months after surgery and the last follow-up,the PEEK group compared with the titanium rod group,the total range of motion of lumbar was statistically significant(P＜0.05).The range of motion(ROM)of the fixed segments decreased in both groups after surgery.The ROM of the fixed segments in PEEK group decreased from(9.5±4.6)° to(4.1±1.9)° at the last follow-up(P＜0.05),which in the titanium rod group was de-creased from(9.8±4.3)°to(0.9±0.5)° at the last follow-up(P＜0.05).The range of motion(ROM)of upper adjacent segment increased in both groups,there was statistical significance in the ROM of upper adjacent segment between the two groups at 12 months after surgery and the last follow-up,(P＜0.05).There was no screw loosening and broken rods in both groups during the follow-up period.Conclusion The PEEK rod semi-rigid pedicle screw internal fixation system used in lumbar non-fusion surgery can retain part of the mobility of the fixed segment,showing comparable short-term clinical efficacy to titanium rod fu-sion.PEEK rod semi-rigid pedicle screw internal fixation system is a feasible choice for the treatment of lumbar spine degener-ative diseases,and its long-term efficacy needs further follow-up observation.

Objective To conduct basic research on the structure and function of the heart in cynomolgus monkeys older than 10 years to provide data for animal selection in elderly disease research.Methods A total of 144 cynomolgus monkeys＞10 years old were selected as research subjects,including 37 females and 66 males in the 10～15 years group,and 21 females and 20 males in the 16～20 years group.Basic data on cardiac structure and function in middle-aged and elderly cynomolgus monkeys were obtained through comparative analysis of general indicators(body mass index,blood pressure,and heart rate),blood biochemical indicators(blood glucose,blood lipids,and ion indicators),and cardiac structure and function indicators.Results General indicators for the 10～15 years and 16～20 years groups were compared.As age increased,the blood pressure and heart rate of female and male monkeys increased,and there was a significant difference in blood pressure changes between male monkeys.A comparison of two sets of blood biochemical indicators showed that,as age increased,blood glucose,triglycerides,total cholesterol,low-density lipoprotein cholesterol,blood calcium,blood sodium,and blood potassium increased,while lactate dehydrogenase decreased,in female and male monkeys.Among these,blood glucose,triglycerides(males),total cholesterol,high-density lipoprotein cholesterol(males),low-density lipoprotein cholesterol(males),blood calcium,blood sodium,blood potassium,and lactate dehydrogenase showed significant changes.A comparison of cardiac contractile function between the two groups showed that,as age increased,the anterior and posterior diameters of the left atrium significantly decreased in both female and male monkeys.Female monkeys showed a significant decrease in the interventricular septal end systolic diameter,left ventricular end diastole and systolic diameters,left ventricular end diastolic and systolic volumes,and left ventricular mass index,while no significant changes were seen in male monkeys.A comparison of diastolic function between the two groups showed that,as age increased,the late diastolic velocity of the mitral valve decreased significantly in male monkeys,while the early diastolic velocity of the left ventricular sidewall increased significantly in female monkeys.Correlation analysis was conducted between the metabolic indicators and the cardiac structure and function indicators of female and male monkeys.The correlations between metabolic indicators and cardiac structure and function indicators were weak in female monkeys,for which the maximum absolute Γ value did not exceed 0.39.However,the correlations between metabolic indicators and cardiac structure and function indicators were relatively strong in male monkeys,for which the maximum absolute Γ value reached 0.66.Conclusions Based on ultrasound analysis combined with metabolic indicators,the heart function of cynomolgus monkeys was studied,and basic data related to the structure and function of the heart in middle-aged and elderly cynomolgus monkeys were obtained.As age increased,blood glucose and lipid indicators increased in cynomolgus monkeys,while cardiac systolic and diastolic functions show a downward trend,similar to changes in middle-aged and older adult human populations.These data provide support for animal selection in research on age-related diseases related to heart function.

Objective:To investigate the relationship and clinical significance of circulating tu-mor DNA(ctDNA)methylation with postoperative recurrence of thyroid cancer.Method:5 pa-tients with recurrent thyroid cancer in our hospital from March 2021 to April 2022 were selected as the observation group,and 2 healthy volunteers were selected as the control group.The level of ctDNA methylation in peripheral blood of the two groups was detected by Illumina high-throughput sequencing system.Gene ontology(GO)function analysis and Kyoto gene and genome encyclope-dia(KEGG)signal pathway analysis were carried out on the methylation region genes with signifi-cant differences through the DAVID gene function analysis platform.Result:There were 7787 dif-ferential ctDNA methylation sites between the two groups.2914(37.4％)were hypermethylation sites and 4873(62.6％)were low methylation sites.GO functional analysis showed that differentially methylated genes were enriched in molecular functions such as DNA-binding transcriptional acti-vation,cell-substrate adhesion,glycoprotein complex and other cellular components.KEGG path-way analysis showed that differentially methylated genes were enriched in thyroid carcinoma signal pathway,cell adhesion molecules,RAP1 signal pathway,RAS signal pathway,MAPK signal path-way and so on.Conclusion:ctDNA methylation may be involved in cancer recurrence in postop-erative patients with thyroid cancer.Monitoring the level of ctDNA methylation in peripheral blood may be an effective method to indicate the recurrence or metastasis of thyroid cancer and guide clinical diagnosis and treatment.

Objective: To investigate the correlation between magnetic resonance imaging-based vertebral bone quality (VBQ) score and screw loosening after dynamic pedicle screw fixation with polyetheretherketone (PEEK) rods, and evaluate its predictive value. Methods: A retrospective analysis was conducted on the patients who underwent dynamic pedicle screw fixation with PEEK rods from March 2017 to June 2022. Data on age, sex, body mass index, hypertension, diabetes, hyperlipidemia history, long-term smoking, alcohol consumption, VBQ score, L1–4 average Hounsfield unit (HU) value, surgical fixation length, and the lowest instrumented vertebra were collected. Logistic regression analysis was employed to assess the relationship between VBQ score and pedicle screw loosening (PSL). Results: A total of 24 patients experienced PSL after surgery (20.5%). PSL group and non-PSL group showed statistical differences in age, number of fixed segments, fixation to the sacrum, L1–4 average HU value, and VBQ score (p < 0.05). The VBQ score in the PSL group was higher than that in the non-PSL group (3.56 ± 0.45 vs. 2.77 ± 0.31, p < 0.001). In logistic regression analysis, VBQ score (odds ratio, 3.425; 95% confidence interval, 1.552–8.279) were identified as independent risk factors for screw loosening. The area under the receiver operating characteristic curve for VBQ score predicting PSL was 0.819 (p < 0.05), with the optimal threshold of 3.15 (sensitivity, 83.1%; specificity, 80.5%). Conclusion The VBQ score can independently predict postoperative screw loosening in patients undergoing lumbar dynamic pedicle screw fixation with PEEK rods, and its predictive value is comparable to HU value.

Purpose: This study explored the association of the elasticity modulus and shear wave velocity (SWV) of the tibialis anterior muscle, as measured by two-dimensional shear wave elastography (2D-SWE), with the intracompartmental pressure (ICP) determined using the Whitesides method in a New Zealand rabbit model of acute compartment syndrome (ACS). Additionally, it evaluated the viability of 2D-SWE as a noninvasive, quantitative tool for the early detection of ACS. Methods: An ACS model was established through direct external compression by applying pressure bandaging to the lower legs of 15 New Zealand rabbits using neonatal blood pressure cuffs. Another five animals represented a non-modeled control group. To measure the elasticity modulus and SWV of the tibialis anterior muscles, 2D-SWE was employed. Blood oxygen saturation, serum creatine kinase (CK), and myoglobin levels were monitored. Subsequently, the anterior tibial compartment was dissected, and the tibialis anterior was removed for hematoxylin and eosin staining to assess muscle injury. Results: The elasticity modulus and SWV of the tibialis anterior muscle increased with compression duration, as did serum CK and myoglobin levels. ICP was strongly positively correlated with these parameters, particularly mean velocity (r=0.942, P<0.001) and CK (r=0.942, P<0.001). Blood oxygen saturation was negatively correlated with ICP (r=-0.887, P<0.001). Histological analysis indicated progressive muscle cell swelling over time, with damage transitioning from reversible to irreversible and culminating in necrosis. Conclusion In a rabbit ACS model, ICP was strongly positively correlated with muscle elasticity modulus/SWV. Consequently, 2D-SWE may represent a novel tool for assessing early-phase ACS.

Objective:To investigate the safety and efficacy of four-hook needle combined with holographic image in robot-assisted partial nephrectomy for completely intrarenal tumors.Methods:The clinical data of 8 patients with completely intrarenal tumors treated by robot-assisted partial nephrectomy with four-hook needle combined with holographic image admitted to General Hospital of Central Theater Command from October 2023 to December 2023 were retrospectively analyzed. There were 6 males and 2 females, with average age of (44.5±12.0) years old. Tumors of 6 cases were in the left side and 2 cases in the right side. The maximum diameter of the tumor was (23.2±8.1) mm. The R. E.N.A.L. score was (9.0±1.4). The preoperative serum creatinine (Scr) was (73.1±14.7) μmol/L. CT-guided four-hook needle was used to locate the edge of completely intrarenal tumor before surgery. During the operation, the tumor was precisely resected under the guidance of hologram and four-hook needle. Perioperative data of patients were collected and analyzed.Results:All the tumor were successfully resected under the guidance of four-hook needle and hologram without conversion to radical nephrectomy or open surgery. The mean operative time was (117.0±14.5) min, the mean hot ischemia time was (20.2±5.1) min, the mean intraoperative blood loss was (75.0±17.3) ml, and the average hospitalization time was (9.5±1.3) days.The one week postoperative Scr was (73.2±14.8) μmol/L, which had no significant difference with that of before operation ( P=0.952). None of them received blood transfusion. The pathology results of 8 patients were clear cell renal cell carcinoma, and the surgical margins were negative. Conclusions:For completely intrarenal tumors, the four-hook needle combined with the hologram can guide the surgeon to quickly locate the tumor, accurately resect the tumor, reduce perioperative complications, and is safe and effective.