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Abstract Background Controversy exists regarding the origin of femoral torsion, and specific treatment rules regarding the optimal position of femoral osteotomy in patients with recurrent patellar subluxation and excessive femoral torsion are scarce. Purpose To establish a novel classification system for such patients, and to compare clinical and radiological outcomes after distal derotational femoral osteotomy (DDFO) between femoral torsion at proximal (neck and shaft) and distal levels. Methods Between January 2014 and June 2019, patients who underwent DDFO were retrospectively reviewed. The segmental torsion analysis was performed to establish a novel classification system, and classify included patients into two groups: 35 patients in proximal torsion group and 38 patients in distal torsion group. These patients were followed-up for at least 3 years. Clinical evaluations included functional outcomes, physical examinations, quality of life, activity level, satisfaction, and complications. Radiological outcomes included patellofemoral osteoarthritis, congruence, and alignment. Results Type I was defined as the proximal torsion. Type II was defined as the distal torsion. Proximal torsion group had lower postoperative femoral torsion (12.6 ± 2.6° vs. 14.8 ± 3.6°; P = .004) and higher surgical correction angle (21.6 ± 5.0° vs. 19.1 ± 3.0°; P = .009). All clinical and radiological outcomes improved significantly in both groups, but proximal torsion group had significantly higher quality of life (EQ-5D-5L: 0.96 ± 0.06 vs. 0.91 ± 0.07; P = .003. EQ-VAS: 92.0 ± 6.0 vs. 88.7 ± 5.8; P = .021) and Tegner activity score (5.2 ± 1.5 vs. 4.5 ± 1.4; P = .040), and fewer patellofemoral osteoarthritis (8.6% vs. 26.3%; P = .048). Two patients in the distal torsion group had subjective patellar instability. The percentage of patients with anterior knee pain was higher in the distal torsion group. Conclusion A novel classification system for patients with recurrent patellar subluxation and excessive femoral torsion based on segmental femoral torsion analysis was established. DDFO was more appropriate for patients with proximal torsion, yielding higher surgical correction angle, and better clinical and radiological outcomes. Study design Cohort study; Level of evidence, 3.

Background: Hip dislocation represents a significant complication encountered following hip arthroplasty procedures. In this investigation, we conducted a comparative analysis of the biomechanical characteristics exhibited by the piriformis and the conjoined tendon after total hip arthroplasty (THA) via the direct anterior approach (DAA), utilizing cadaveric specimens. The objective is to ascertain the relative significance of the piriformis muscle and the conjoined tendon in mitigating hip dislocation. Methods: A total of 16 hip joints from 8 freshly frozen cadavers were selected and stratified into 2 groups: the piriformis tendon (PT) group and the conjoined tendon (CT) group. Following THA via the DAA, measurements were taken to record the torque required to induce hip dislocation under various conditions. Torque readings were obtained with the tendon in its intact state (intact group) and after preservation or reconstruction of either the PT or the CT. Results: The torques of anterior and posterior dislocation in PT group were 22.24 ± 4.53 N.m and 30.7 ± 15.5 N.m following tendon severed, and 20.04 ± 2.67 N.m and 17.5 ± 6.7 N.m following reconstruction. There were no differences compared to the intact group. The torque decreased in the CT group after CT was severed with the torques dropping from 31.2 ± 7.6 N.m to 8.18 ± 2.6 N.m (P < .0001) for anterior dislocation, and from 34.9 ± 8.3 N.m to 9.8 ± 2.8 N.m (P < .0001) for posterior dislocation. Following reconstruction, the torque required for dislocation significantly increased (P < .0001). Conclusions: This study underscores the preeminent role of the CT in ensuring hip stability following THA via DAA, highlighting the cruciality of its preservation and reconstruction during surgical interventions.

Grain boundaries (GBs) play a crucial role on the structural stability and mechanical properties of Cu and its alloys. In this work, molecular dynamics (MD) simulations are employed to study the effects of Fe solutes on the formation energy, excess volume, dislocations and melting behaviors of GBs in CuFe alloys. It is illustrated that Fe solute affects the structural stability of Cu GBs substantially, the formation energy of GBs is reduced, but the thickness and melting point of GBs are increased, that is, the structural stability of Cu GBs is significantly improved owing to the Fe solutes. A strong scaling law exists between the formation energy, excess volume, thickness and melting point of GBs. Therefore, Fe solid solute plays an important role in the characteristics of GBs in bi-crystal Cu.

Abstract Background Proper lower limb alignment and soft tissue balance are significant indicators to measure the success of total knee arthroplasty (TKA). Previous studies have confirmed that soft tissue relaxation around the knee after TKA will change over time; however, the relationship between lower limb alignment and soft tissue balance after TKA remains unclear. We studied (1) whether the change of soft tissue balance around the knee with time after posterior-stabilized (PS) TKA would affect the alignment of the lower limbs; (2) Whether the accuracy of lower limb alignment during PS TKA affects postoperative soft tissue remodeling. Methods In this study, 100 patients were recruited after PS TKA. Among them, 50 patients with a hip knee ankle (HKA) angle of ≤ ± 3° were set as the neutral group, and 50 patients with an HKA angle of > ± 3° were set as the deviation group. The imaging results measured the HKA angle before the operation as well as the HKA, varus, and valgus angles at 1, 3, 6, 12, and 24 months after TKA. Clinical assessment included range of motion (ROM), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Knee Society Score (KSS). Results Eight people were excluded from the study. After the exclusion, the study enrolled 47 patients in the neutral group and 45 patients in the deviant group and were followed for up to 2 years. There was no statistical significance in mean varus angles as well as HKA angle changes during the follow-up phase of each groups (P > 0.05). The mean valgus angles of the patients in the neutral group group were 2.47°, 3.45°, 3.63°, 3.60° and 3.63°, and in the deviation group were 2.45° (P = 0.841), 2.88° (P

Abstract Background Osteoarthritis (OA) is a chronic disease of the bones and joints that commonly affects middle-aged and elderly individuals, characterized by the degeneration of articular cartilage and inflammation of the joints. The molecular mechanisms of OA urgently need to be further examined. Our study intended to uncover circ-NFKB1/miR-203a-5p/ERBB4 axis in regulating interleukin-1β (IL-1β) induced chondrocytes apoptosis. Methods GSE178724, GSE79258 and GSE169077 were downloaded from Gene Expression Omibus (GEO) database and differentially expressed circRNAs, miRNAs and mRNAs were obtained by R software. Annexin V assay was used to determine cell apoptosis rate. ELISA was further performed to identify the inflammation response. Dual-luciferase reporter gene assay was conducted to examine the combination among circ-NFKB1, miR-203a-5p and ERBB4. Results Our research demonstrated that circ-NFKB1 and ERBB4 were significantly upregulated through bioinformatic analysis. MiR-203a-5p was significantly downregulated through bioinformatic analysis. Silencing of circ-NFKB1 notably inhibited the IL-1β induced chondrocytes apoptosis and upregulated ERBB4 expression. Through prediction on bioinformatics analysis, miR-203a-5p was the target binding circ-NFKB1, and ERBB4 was the potential target of miR-203a-5p. Subsequently, these changes induced by the silencing of circ-NFKB1 were reversed upon addition of pcDNA/ERBB4. Conclusions Silencing circ-NFKB1 could sponge miR-203a-5p to regulate ERBB4 expression and alleviate OA progression.

This article examines the digital and cinematic mediation of queer memory in four independent Chinese documentaries: Queer China, “Comrade” China (dir. Cui Zi’en 2008), Our Story (dir. Yang Yang, 2011), We Are Here (dir. Shi Tou and Jing Zhao, 2016) and Shanghai Queer (dir. Chen Xiangqi, 2019). All these films have been made by queer identified filmmakers and have used the digital video documentary format as an activist strategy; all have strived to record China’s queer history in the post-Mao era. However, because of the filmmakers’ gender and sexual subjectivities, together with the historical and social contexts in which these films were made, the four documentaries remember China’s queer history in different ways. Together, these documentaries contest a heteronormative and a homonormative narrative of Chinese history by constructing alternative memories; they also insert queer people’s voices and experiences into that history. All these mediations testify to the heterogeneity of queer people’s experience, as well as the overdetermination of queer memory as a result of a contingent assemblage of factors such as time, place, technology and filmmaker’s gender and sexual subjectivities. [ABSTRACT FROM AUTHOR]