ObjectiveTo investigate the association of physical activity and balance ability with disability, and to further examine the mediating role of balance ability in the relationship between physical activity and disability. MethodsBased on data from 2021 to 2023 National Health and Nutrition Examination Survey (NHANES) cycle, a multivariable Logistic regression model was constructed to evaluate the independent association of physical activity and balance ability with disability, with covariates adjusted in four steps. An interaction model was further developed to assess the multiplicative interaction between physical activity and balance ability. Mediation analysis was performed using the Baron and Kenny three-step approach to examine the mediating role of balance ability, and the proportion of the mediation effect was calculated. The significance of the mediation effect was assessed using the Delta method, and robustness was verified through the Bootstrap method with a fixed random seed. Multiple sensitivity analyses were conducted to ensure the stability of the results. ResultsA total of 3 902 participants were included, with a prevalence of disability of 17.7%. Multivariable regression analysis showed that, after adjusting for all covariates, both light-intensity physical activity (LIPA) (OR = 0.489, 95%CI 0.380 to 0.629, P < 0.001) and high-intensity physical activity (HIPA) (OR = 0.493, 95%CI 0.371 to 0.656, P < 0.001) were significantly associated with a reduced risk of disability, whereas impaired balance ability was significantly associated with an increased risk (OR = 1.579, 95%CI 1.266 to 1.970, P < 0.001). The interaction effect analysis showed that the interaction between physical activity and balance ability were not significant (P > 0.05), however, the main effect of LIPA remained robust (β = -0.597, SE = 0.221, OR = 0.550, P = 0.007), while impaired balance ability was significantly associated with an increased risk of disability (β = 0.577, SE = 0.231, OR = 1.780, P = 0.012). The mediation analysis further indicated that balance ability played a robust mediating role in the association between LIPA and disability, with a mediation proportion of 21.1%. The indirect effect (a × b) was statistically significant (P < 0.001), and the 95% confidence intervals derived from the bootstrap method did not include zero. ConclusionPhysical activity and balance ability are significantly associated with disability, and balance ability may mediate the relationship between physical activity and disability, highlighting its potential value in disability risk assessment and intervention strategies.

Objective:To explore the effect of SQLE on the biological characteristics of pan-cancer,using bioinformatics methods to predict and analyze the correlation between SQLE and the clinical prognosis and immunity of pan-cancer.Methods:The ex-pression level of SQLE in tumor and normal tissues and its correlation with different clinical stages of pan-cancer were analyzed,and the relationship between SQLE expression and overall survival and tumor microenvironment were evaluated.Gene enrichment analysis was conducted to study the biological functions and signaling pathways related to SQLE gene,then,calculate the correlation between SQLE gene and tumor mutation load and microsatellite instability,and analyze the correlation between SQLE gene and immunomodula-tory genes.Results:SQLE gene was highly expressed in variety of tumors,and differentially expressed in different tumor stages.High expression of SQLE was a risk factor in variety of tumors.Patients with high expression of SQLE hade a worse prognosis.SQLE was cor-related with TMB and MSI,and involved in tumor development through different pathways.Conclusion:SQLE,as a valuable prognos-tic biomarker and new therapeutic target for variety of cancers,has certain application value in basic research and clinical treatment of various cancers.

Hoffa fracture of tibial plateau is a special type of coronal fracture of tibial plateau, among which occult fracture accounts for a large proportion, resulting in missing diagnosis and delayed treatment. The current studies are all case reports, and the incidence, diagnostic protocol, injury characteristics and injury mechanism of Hoffa fracture have not been systematically studied. The commonly used classifications such as AO type, Schatzker type, three-column classification and comprehensive classification of tibial plateau cannot cover this type. In this study, a retrospective case series study was performed for the clinical data of 3 086 patients with tibial plateau fractures. There were 13 patients with Hoffa fracture of tibial plateau, and 23% of them were occult ones. The injury mechanism of this fracture was as follows: under the state of knee joint flexion, axial violence through femur concentrated on the posterior half of tibial plateau, with the knee joint in transient varus and pronation position, leading to the posteromedial coronal splitting fracture. According to the position and degree of fracture displacement involving the joint, the fracture was divided into three type: type I involving the articular surface of tibial plateau fracture less than 1/4, type II involving the articular surface of tibial plateau equal to or more than 1/4 and less than 1/2, type III involving the joint face equal to or more than 1/2. Each fracture type was divided into three subtypes, of which subtype A was non-displaced fracture, subtype B had articular surface displacement<2 mm, and subtype C had articular surface displacement≥2 mm. According to the classification characteristics, the treatment principles were proposed. The authors systematically summarized the Hoffa fracture of tibial plateau for the first time in aspects of the incidence, injury characteristics, injury mechanism, fracture classification and treatment principles, which is helpful to avoid missed diagnosis and improve treatment efficacy.

Objective:To understand and verify the biomechanical mechanism of tibial plateau Hoffa (coronal) fracture by simulating high-altitude falls and traffic injuries using knee joint specimens.Methods:Ten specimens of lower limb knee joint were used. They were from 6 males and 4 females, with an average age of 57.4 years (from 42 to 65 years). They were divided into 2 equal groups: one subjected to simulation of high-altitude falls (fall group) and the other to simulation of traffic injury (traffic injury group). After injury simulation, standard orthographic and lateral X-ray examinations and CT scans were performed of the knee joints in the extended position to observe whether there was a fracture, where the fracture occurred, and how the fracture line went.Results:A tibial plateau coronal fracture was successfully simulated in 6 cases, but not in the other 4 cases. The failure was attributed to femoral fractures and other types of tibial plateau fracture. In the 3 successful fractures simulated by high-altitude fall, the fracture line was located all on the posterior medial side, involving the posterior 1/3, 2/5, and 1/2 of the tibial plateau, respectively. The fracture line and the coronal plane formed angles of 21°, 19° and 12°, respectively. The fracture was not shown on X-ray film in one case which was a posterior medial fracture on CT. In the other 3 successful fractures simulated by traffic injury, the fracture line involved 1/6, 1/4 and 1/3 of the posterior tibial plateau, respectively. The angles between the fracture line and the coronal plane were 47°, 56° and 63°, respectively. One case showed no obvious fracture signs on the X-ray but a coronal fracture on CT.Conclusions:This study has confirmed for the first time that both high-altitude falls and traffic injuries can cause coronal fractures of the tibial plateau which vary significantly in the extent of involvement and morphology. X-rays are not sufficient to fully diagnose this type of fractures, suggesting that patients with a clear history of knee flexion or axial violence injury should be routinely scanned by CT to reduce risks of missed diagnosis and insufficient treatment.