Objective: To compare the biomechanical performance between the single- versus double-threaded cannulated screws in the treatment of femoral neck fractures of Pauwels type Ⅲ. Methods: Models of femoral neck fracture of Pauwels type Ⅲ (70°) were made of the Sawbone synthetic composite femurs. All specimens were divided into 2 groups (n=12). Group A was fixated with single-threaded cannulated screws and group B with double-threaded cannulated screws, both in an inverted triangle configuration. The screws ranged from 90 to 95 mm in length and from 7.3 to 7.5 mm in diameter. All the specimens were subjected to axial stiffness and failure load tests with 7° valgus (simulating normal two-legged weight-bearing stance) and 25° valgus (simulating normal one-legged weight-bearing stance) and torsion test as well. The 2 groups were compared in the torques at axial stiffness angles of 1°, 2°, 3°, 5° and 7°. Results: Group B had significantly greater axial stiffness at 7° valgus and 25° valgus (89±26 N/mm and 128±37 N/mm) and failure load (1,154±368 N) than group A did (36±12 N/mm and 47±16 N/mm; 688±94 N) (P< 0.05). The torques increased with the increase in rotation angle in both groups. However, the torques in group B (3.26±0.96, 4.16±1.23, 4.64±1.13, 5.59±1.26 and 6.53±1.47 N·m) were all significantly larger than in group A (1.44±0.19, 2.03±0.41, 2.33±0.62, 2.74±0.87 and 3.05±1.07 N·m) (P<0.05). Conclusion Double-threaded cannulated screws may provide better biomechanical stability than single-threaded ones, due to their substantial improvement in anti-compression and anti-rotation performance.

BACKGROUND:Research on foot and ankle proprioception is crucial for the rehabilitation of chronic ankle instability and geriatric diseases as well as for the improvement of body posture control and motor performance.Previous studies have often studied the sensory evaluation of the foot and ankle joints separately,which has limitations for a comprehensive understanding of their sensory function. OBJECTIVE:The foot and ankle complex is the only part in direct contact with the support surface,and plays an important role in the collective sensory feedback and regulation and balance control.By combing the existing investigation and research of foot and ankle ontology,the measurement and evaluation methods of the sensation of the foot and ankle complex are combed,in order to pave the way and provide the theoretical basis for future related studies. METHODS:Chinese terms"(foot OR foot ankle OR ankle)AND(sensation OR proprioception)"and English terms"(foot OR ankle)AND(feel OR proprioception)"were used as the keywords for retrieving relevant literature in the Web of Science,PubMed,and CNKI.We understood the basic concepts,current status and scope of research on the foot and ankle,summarized and evaluated the proprioceptive evaluation methods of the foot and ankle,and finally included 57 papers for further review. RESULTS AND CONCLUSION:The evaluation of foot and ankle complex sensation was mainly divided into sensory evaluation of the foot and proprioceptive evaluation of the ankle joint.The sensory evaluation of the foot mainly describes the sensation of the skin and the sensory feedback under the intervention conditions.The methods mainly include the pressure sensory threshold test,the two-point discrimination test of the foot(planar and plantar),and the duration test of skin vibration sensation.Ankle joint proprioception evaluation focuses on the description of joint position,motion range,force value and functional performance.The methods are mainly divided into static joint angle reset test,motion minimum threshold test,force perception reproduction test and dynamic balance,speed and walking ability tests.The report of quantitative results is generally expressed by"an error,"which is generally divided into absolute error,relative error,constant error,etc.To conclude,the foot and ankle complex has specific sensory capabilities,including foot sensation and ankle proprioception,which affect the quality of life and athletic performance of humans.Weakness of both foot sensation and ankle proprioception is associated with reduced human balance,and the combined measurements of the two can comprehensively and effectively evaluate foot and ankle function.The combination of foot and ankle sensory measures is selected according to different research needs and various influencing factors such as environment,emotion and reporting style are fully considered,to improve the validity of measurement and evaluation.

Objective: This cross-sectional study aimed to investigate the characteristics of malocclusions in scoliotic patients through clinical examinations. Methods: Fifty-eight patients with idiopathic scoliosis (IS) and 48 patients with congenital scoliosis (CS) participated in the study. A randomly selected group of 152 orthopedically healthy children served as the control group. Standardized orthodontic and orthopedic examination protocols were used to record the occlusal patterns and type of scoliosis. Assessments were made by three experienced orthodontists and a spinal surgery team. The differences in the frequency distribution of occlusal patterns were evaluated by the chi-squared test. Results: In comparison with patients showing IS, patients with CS showed a higher incidence of Cobb angle ≥ 45° (p = 0.020) and included a higher proportion of patients receiving surgical treatments (p < 0.001). The distribution of the Angle Class II subgroup was significantly higher in the IS (p < 0.001) and CS (p = 0.031) groups than in the control group. In comparison with the healthy controls, the CS and IS groups showed significantly higher (p < 0.05) frequencies of asymmetric molar and asymmetric canine relationships, upper and lower middle line deviations, anterior deep overbite, unilateral posterior crossbite, and canted occlusal plane, with the frequencies being especially higher in CS patients and to a lesser extent in IS patients. Conclusions Patients with scoliosis showed a high frequency of malocclusions, which were most obvious in patients with CS.

Objective:To investigate the current situation of expected sadness of family caregivers of first stroke patients and analyze its influencing factors, so as to provide reference for the formulation of psychological decompression intervention program for family caregivers of stroke patients.Methods:Convenience sampling method was used to conduct cross-sectional survey of 212 family caregivers of first stroke patients who were hospitalized in the First Affiliated Hospital of Shandong First Medical University from March 2020 to May 2021, using general information questionnaires and Anticipatory Grief Scale and Connor-Davidson Resilience Scale to investigate and anlalyzed its influencing factors.Results:The scare of anticipatory grief of the caregivers of first stroke patients was 87.93 ± 17.36. The results of multiple stepwise regression analysis showed that the age of family caregivers, psychological elasticity, the degree of relationship with patients, patients′ cognitive ability and self-care ability were the influencing factors of anticipatory grief of family caregivers of first stroke patients ( t values were -6.73 -11.77, P <0.05). Conclusions:The caregivers of first stroke patients have serious anticipatory grief. Staff should pay attention to the psychological conditions of the family caregivers and take effective measures to promote their physical and mental health.

Objective:To analyze the Risk factors for rapid progression of inpatients with anti-melanoma differentiation associated gene5 (MDA5) antibody-positive dermamyositis (DM) complicated with interstitial lung disease (ILD), and construct a clinical predictive model.Methods:A total of 63 hospitalized patients with anti MDA5 positive DM combined with ILD (MDA5+ DM-ILD) from January 1, 2016 to May 30, 2022 at the Second Affiliated Hospital of the Air Force Military Medical University were included in the study. They were divided into a control group (DM-ILD) and an observation group (DM-RPPILD) based on whether they had rapidly progressing interstitial lung disease (RPILD). Retrospective collection and organization of clinical case data from patients were conducted, and binary logistic regression was used to summarize the risk factors of DM-RPILD. R software was used to construct a clinical prediction model for RPILD occurrence using training set data, and validation set data was used to verify the predictive ability of the model.Results:The proportion of patients with SpO 2<90% at the initial diagnosis of ILD, the titers of anti MDA5 antibodies, immunoglobulin M (IgM), serum ferritin (FER) levels, and positive rates of anti Ro52 antibodies in the observation group were higher than those in the control group, the lymphocyte (LYM) count level was lower than that of the control group (all P<0.05). Binary logistic regression analysis showed SpO 2<90% at the initial diagnosis of ILD, FER level, LYM count, and anti Ro52 antibody were the influencing factors for the occurrence of RPILD (all P<0.05). The area under the curve (AUC) of the training set prediction model for predicting resistance to MDA5+ DM-RPILD was 0.922(95% CI: 0.887-0.957), with a sensitivity of 95.7% and a specificity of 72.5%; In the validation set, the prediction model predicted an AUC of 0.939(95% CI: 0.904-0.974) for resistance to MDA5+ DM-RPILD, with a sensitivity of 90.0% and a specificity of 88.9%; The calibration curves of the training and validation sets indicated that the predictive model had good calibration ability. Conclusions:SpO 2<90% at the initial diagnosis of ILD, FER levels increase, LYM count levels decrease, and anti Ro52 antibody positivity are risk factors for RPILD. The constructed clinical model has good predictive ability and has certain guiding significance for clinical work.

Objective:To investigate the clinical safety and efficacy of tirofiban in the treatment of hemiplegic stroke warning syndrome.Methods:Patients with hemiplegic stroke warning syndrome admitted to Jining First People's Hospital without receiving intravenous thrombolysis from January 2018 to May 2020 were enrolled retrospectively. Some patients were given tirofiban intravenous infusion for at least 24 h in acute phase, then received oral antiplatelet therapy (tirofiban group); some only received aspirin+ clopidogrel dual antiplatelet therapy (control group). The primary endpoint was muscle strength at the paralytic side and National Institutes of Health Stroke Scale (NIHSS) score at day 7 after onset. The secondary endpoint was the modified Rankin Scale (mRS) score at 3 months after onset, and ≤2 was defined as good clinical outcome. The safety endpoint was the bleeding events during treatment. Multivariate logistic regression analysis was used to determine the independent influencing factors of clinical outcome. Results:A total of 30 patients with hemiplegic stroke warning syndrome were enrolled, including 19 (63.3%) in the tirofiban group and 11 (36.7%) in the control group. There was no significant difference in baseline clinical data between the two groups, and no drug-related bleeding complications occurred during treatment. The muscle strength at paralytic side and NIHSS score at day 7 after onset, NIHSS score at discharge and good clinical outcome rate at 3 months in the tirofiban group were significantly better than those in the control group, and the differences were statistically significant (all P<0.05). Multivariate logistic regression analysis showed that tirofiban was an independent protective factor for good outcome after adjusting the NIHSS score at the beginning of treatment (odds ratio 0.040, 95% confidence interval 0.040-0.449; P=0.009). Conclusions:Tirofiban is safe and effective in the treatment of patients with hemiplegic stroke warning syndrome in acute phase. It can effectively block the progress of the disease, improve the outcome of patients, and will not increase the risk of bleeding.

Objective To explore the correlation between pregnancy-related anxiety and serum 25 (OH)D level during early pregnancy. Methods A radioimmunoassay was used to determine the serum 25 (OH)D levels of 2 122 early pregnant women in Maanshan Maternal and Child Health Care Hospital, from June 2015 to 2016. Data were collected using a questionnaire. Results The mean serum 25(OH)D level was(29.71±32.27)nmol/L.About 15.2% of the subjects had adequate,22.6% had insufficient,45.1% had deficient,and 17.1% had severely deficient serum 25(OH)D levels.The type of housing and testing seasons were significantly associated with the serum 25(OH)D level.Single factor logistic regression analysis results show that pregnancy-related anxiety incidence in the group deficient in 25(OH)D was higher than that in the adequate group, which has a statistically significant difference (P<0.05). After adjusting for the maternal age,BMI,and educational level,multivariate logistic regression analysis results showed that the difference was statistically significant. Conclusion The serum 25(OH)D level in early pregnant women was inadequate. Furthermore, lack of serum 25(OH)D in early pregnancy and pregnancy-related anxiety were negatively correlated.

Artificial joint replacement is an important means for the treatment of severe joint end-stage diseases such as hip and knee joint,which has obtained satisfactory clinical efficacy,but the postoperative periprosthetic osteolysis (PPO),which is mediated by wear particles,restricts the long-term effect of artificial joints.It is found that wear particles increase the expression of cytokines and inflammatory factors by stimulating the cells around the prosthesis,activate different signaling pathways,promote the imbalance between bone formation mediated by local osteoblasts and bone resorption mediated by osteoclast so as to lose of the local bone mass,and eventually produce osteolysis and aseptic loosening.This article reviews the different signal pathways activated by wear particles in recent years,in order to explore the pathogenesis of PPO and to open up new avenues for its prevention and treatment.

Objective:To investigate the effects of marathon exercise on knee cartilage volume and T2 relaxation time (T2 value) based on MRI.Methods:From December 2018 to December 2021, 25 healthy volunteers without long-distance running habits and 32 non-professional marathon runners with long-term long-distance running were recruited to undergo knee MRI 3D water-selective excitation (three dimensional water-selective excitation, 3D-WATS) and T2 mapping imaging were performed, and the cartilage volumes in 5 knee areas and T2 values in 42 subareas were extracted for analysis. To compare the cartilage volume and its ratio to body surface area of knee joint of healthy volunteers and non-professional marathon runners, the T2 value of cartilage in each subregion, and the correlation between marathon exercise intensity and the volume and T2 value of cartilage in different regions.Results:Compared with healthy volunteers, there was no significant difference in cartilage volume or the ratio of body surface area to body volume of non-professional marathon runners ( P>0.05). There were significant differences between healthy volunteers and non-professional marathon runners in cartilage T2 values of the median layer of medial condyle of femur (47.61±5.65 ms and 44.29±6.10 ms) and the deep layer of medial condyle of femur (36.82±9.05 ms and 31.67±7.59 ms), deep precondylar area of medial femur (38.37±4.68 ms and 34.09±4.19 ms), shallow area of medial condylar area of femur (52.17±11.11 ms and 45.51±7.76 ms), middle layer of medial condylar area of femur (49.09±5.08 ms and 45.63±5.04 ms), medial layer of anterior condylar region of lateral femur (45.69±4.68 ms and 42.57±5.77 ms), superficial layer of posterior condylar region of lateral femur (55.42±18.41 ms and 47.99±8.39 ms), deep layer of anterior tibial medial plateau (33.40±7.76 ms and 29.03±5.69 ms), deep layer of posterior tibial medial plateau (31.28±5.02 ms and 27.92±5.99 ms), deep layer of patellofemoral surface (35.65±6.99 ms and 32.30±5.28 ms), respectively ( P<0.05). In non-professional marathon runners, the medial tibial plateau cartilage volume was negatively correlated with step frequency ( r=-0.371, P=0.035), the lateral femoral condylar cartilage volume was negatively correlated with step frequency ( r=-0.365, P=0.043), and the lateral tibial plateau cartilage volume was negatively correlated with step frequency ( r=-0.550, P=0.001). The T2 value of the medial layer cartilage in the anterior tibial medial plateau region was negatively correlated with body weight ( r=-0.277, P=0.039) and body mass index ( r=-0.290, P=0.030). The T2 value of the superficial layer of patellofemoral surface was negatively correlated with the amount of running in 3 months ( r=-0.457, P=0.010). The superficial T2 value in the posterior lateral plateau of the tibia was negatively correlated with stride length ( r=-0.437, P=0.014), and the medial layer cartilage T2 value in the anterior condylar area of the lateral femur was negatively correlated with stride frequency ( r=-0.380, P=0.035). Conclusion:Marathon exercise had little effect on the knee cartilage volume, but had a certain effect on the cartilage T2 value, resulting in changes in cartilage structure. The higher the step frequency, the smaller the cartilage volume. The greater the body weight or body mass index, the greater the amount of running in 3 months, and the greater the stride length, the lower the cartilage T2 value.

Objective : To study the effect of anterior traction on the temporomandibular joint in adolescent patients with skeletal Class Ⅲ malocclusion. Methods: Twenty-nine patients with early permanent dentition with skeletal class Ⅲ malocclusions were measured by cephalometry and a coordinate system before and after maxillary protraction. The correlation between dentofacial structures and the temporomandibular joint was analyzed. Results : After maxillary protraction, cephalometric measurements showed that the dentofacial structure changed significantly; ANB increased by 3.97° ± 2.32° (P<0.001); U1-SN increased by 4.97° ± 5.51° (P<0.001); L1-MP decreased by 1.26° ± 1.41° (P = 0.008); and MP-SN increased by 1.02° ± 3.90° (P = 0.003). The coordinate system measurement showed that the S-Fpx was decreased by 0.16 ± 1.52 mm (P = 0.041), the S-Ciy distance was significantly decreased by 0.09 ± 2.03 mm (P = 0.028), and there was no significant change in the temporomandibular joint spaces (A, P, and C) (P>0.05). Correlation analysis showed a moderate negative correlation between the posterior margin of the temporomandibular joint fossa and U1-SN (r = -0.427, P = 0.042). There was a moderate positive correlation between the leading edge of the condyle and ANB (r = 0.425, P = 0.043); there was no correlation between the joint space and dentofacial changes. Conclusion After treatment with maxillary protraction for adolescent skeletal class Ⅲ malocclusion, maxillary protraction had some effect on changes in the temporomandibular joint fossa and condyle and had no effect on the joint space.