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Backward-compatible stereoscopic display, a novel display technique that can simultaneously present satisfying 3D effects to viewers with stereo glasses and clear 2D contents to viewers without, aims at helping the people who are unsuitable for watching 3D movies for a long time. In this article, we introduce two versions of backward-compatible stereoscopic display: the simpler version is far simpler than Hidden Stereo (the state-of-the-art method) while preserving competitive 2D–3D effects; the advanced version, which we call 2D-Ghost-Free Stereoscopic Display, overcomes the limitation that Hidden Stereo and the simpler version are both confined to small absolute disparity. 2D-Ghost-Free Stereoscopic Display improves tolerable disparity range by adding depth-of-field in the regions with large disparity, so that it can be applied to more scenes of 3D movies. User experiments and theoretical analysis both demonstrate the superiority of the 2D-Ghost-Free Stereoscopic Display over the state-of-the-art method and our simpler version. In addition, to make the user experiments double-blind and automatic, we developed a user study system that can automatically present 3D images and videos in NVIDIA 3D Vision 2 and collect corresponding votes of subjects on stimuli, whereas the previous researchers did not state that their user experiments were double-blind.

Objective. Evaluate the effectiveness of extracellular vesicles derived from mesenchymal stem cells (MSCs) in the treatment of chronic kidney disease based on meta-analysis. Methods. We searched CNKI, Wanfang, VIP, SinoMed, PubMed, Cochrane Library, EMbase, Web of Science and other databases on randomized controlled trial (RCT) of oral traditional Chinese patent medicines and simple preparations to improve inflammatory response in patients with diabetes nephropathy. The search time was from the establishment of the database to October 2022. All researchers independently screened and extracted documents for quality evaluation. Data analysis was conducted on documents that met quality standards using Stata 16.0 software and RevMan 5.4. Results. 12 studies (n=198) satisfied the inclusion criteria.The results demonstrated that the levels of Scr (SMD=-0.38;95%CI=-4.29,-1.87;PPPPP=0.003) and the apoptotic cells (SMD=-3.85%, 95%CI=-5.05, -2.65;P＜0.00001) were significantly decreased in the EV group. Conclusion. The results confirmed that MSCs-EV therapy could improve renal function and delaying kidney fibrosis in preclinical animal CKD model.

PurposeTo improve the accuracy of parameter prediction for small-sample data, considering the existence of error in samples, the error circle is introduced to analyze original samples.Design/methodology/approachThe influence of surface roughness on fatigue life is discussed. The error circle can treat the original samples and extend the single sample, which reduces the influence of the sample error.FindingsThe S-N curve obtained by the error circle method is more reliable; the S-N curve of the Bootstrap method is more reliable than that of the Maximum Likelihood Estimation (MLE) method.Originality/valueThe parameter distribution and characteristics are statistically obtained based on the surface roughness, surface roughness factor and intercept constant. The original sample is studied by an error circle and discussed using the Bootstrap and MLE methods to obtain corresponding S-N curves. It provides a more trustworthy basis for predicting the useful life of products.

Software-defined networking (SDN), a novel network paradigm, separates the control plane and data plane into different network equipment to realize the flexible control of network traffic. Its excellent programmability and global view present many new opportunities. DDoS detection under the SDN context is an important and challenging research field. Some previous works attempted to collect and analyze statistics related to flows, usually recorded in switches, to address DDoS threats. In contrast, other works applied machine learning-based solutions to identify DDoS and achieved promising results. Generally, most previous works need to periodically request flow rules or packets to obtain flow statistics or features to detect stealthy exceptions. Nevertheless, the request for flow rules is very time-consuming and CPU-consuming; moreover may congest the communication channel between the controller and the switches. Therefore, we present FORT, a lightweight DDoS detection scheme, which spreads the rule-based detection algorithm at edge switches and determines whether to start it by periodically retrieving the ports state. A time-series algorithm, ARIMA, is utilized to determine the port statistics adaptively, and an SVM algorithm is applied to detect whether a DDoS attack does occur. Representative experiments demonstrate that FORT can significantly reduce the controller load and provide a reliable detection accuracy. Referring to the false alarm rate of 1.24% in the comparison scheme, the false alarm rate of this scheme is only 0.039%, which significantly reduces the probability of false alarm. Besides, by introducing the alarm mechanism, this scheme can reduce the load of the southbound channel by more than 60% in the normal state.

Nuclear receptor 4A1 (NR4A1), a member of the NR4A subfamily, acts as a gene regulator in a wide range of signaling pathways and responses to human diseases. Here, we provided a brief overview of the current functions of NR4A1 in human diseases and the factors involved in its function. A deeper understanding of these mechanisms can potentially improve drug development and disease therapy.

Salt-tolerant superabsorbent polymer (SAP) was synthesized to improve the water retention properties of saline-alkali soil. The Lop Nur saline-alkali soil of Xinjiang with high salinity (total dissolved salt: 18.13wt%) was the object of improvement. The good swelling capacity of SAP (69.04 g/g) under high salinity condition contributed to the superb slow-release water property and further [showed](https://www.wordhippo.com/what-is/another-word-for/build.html) [excellent](https://www.wordhippo.com/what-is/another-word-for/excellent.html) water retention property of SAP-saline-alkali soil (28 days), which showed a good application potential of SAP in saline-alkali land. The swelling mechanism under high salt condition was also explored. Notably, owe to the complexation reaction between and three hydrophilic groups of SAP, the swelling capability of SAP tended to keep steady when the concentration of CaCl exceeded 0.55wt%. Interestingly, the distribution of the calcium salt in SAP was directly displayed by the maximum intensity projection of computed tomography.

SARS‐CoV‐2 attaches to its host receptor, angiotensin‐converting enzyme 2 (ACE2), via the receptor‐binding domain (RBD) of the spike protein. The RBD glycoprotein is a critical target for the development of neutralizing antibodies and vaccines against SARS‐CoV‐2. However, the high heterogeneity of RBD glycoforms may lead to an incomplete neutralization effect and impact the immunogenic integrity of RBD‐based vaccines. Investigating the role of different carbohydrate domains is of paramount importance. Unfortunately, there is no viable method for preparing RBD glycoproteins with structurally defined glycans. Herein we describe a highly efficient and scalable strategy for the preparation of six glycosylated RBDs bearing defined structure glycoforms at T323, N331, and N343. A combination of modern oligosaccharide, peptide synthesis and recombinant protein engineering provides a robust route to decipher carbohydrate structure‐function relationships., The first chemical synthesis of homogeneous glycoforms of the SARS‐CoV‐2 spike receptor‐binding domain (RBD) has been accomplished via the combination of protein and carbohydrate chemistry. This strategy provides a versatile synthetic platform for homogeneous glycosylated RBDs of the SARS‐CoV‐2 S protein and other related virus proteins and a powerful tool for investigating the functions of RBD glycans.

As one of the essential components of the braking system, the high-speed train brake disc is an integral part of ensuring the safety of the train. The main objective of this study is to conduct thermal analysis and reliable life prediction on brake discs. The research was conducted by developing a programmer spectrum of brake discs with high-speed train brake discs. According to the results of numerical analysis and the S-N curve of the material, the temperature distribution on the surface of the brake disc is determined, and the fatigue life of the brake disc is predicted. The comparison with the service life of the brake disc verifies the rationality of the calculation results. In addition, a fatigue damage probability model of brake discs is established based on the theory of fatigue cumulative damage. Through the relationship between the reliability of mechanical parts and the number of load cycles, the reliable life of the brake disc under different working conditions is predicted. This work establishes a method of reliable life analysis for brake discs of high-speed trains based on the load spectrum, which could analyze the life and reliability of brake discs more systematically.

Bone marrow mesenchymal stem cell (BMSC) chondrogenic differentiation contributes to the treatment of osteoarthritis (OA). Numerous studies have indicated that microRNAs (miRNAs) regulate the pathogenesis and development of multiple disorders, including OA. Nevertheless, the role of miR-20a-5p in OA remains obscure. Forty male C57BL/6 mice were divided into four groups and were surgically induced OA or underwent sham surgery in the presence or absence of miR-20a-5p. Flow cytometry was implemented to detect surface markers of BMSCs. Reverse transcription quantitative polymerase chain reaction revealed the upregulation of miR-20a-5p during BMSC chondrogenic differentiation. Western blotting displayed that miR-20a-5p inhibition decreased protein levels of cartilage matrix markers but enhanced those of catabolic and hypertrophic chondrocyte markers in BMSCs. Alcian blue staining, hematoxylin‑eosin staining and micro-CT revealed that miR-20a-5p inhibition restrained chondrogenic differentiation and miR-20a-5p overexpression promoted the repair of damaged cartilage and subchondral bone, respectively. Luciferase reporter assay identified that mitogen activated protein kinase kinase kinase 2 (Map3k2) was a target of miR-20a-5p in BMSCs. Moreover, the expression of miR-20a-5p and Map3k2 was negatively correlated in murine cartilage tissues. Knocking down Map3k2 could rescue the suppressive influence of miR-20a-5p inhibition on chondrogenic differentiation of BMSCs. In conclusion, miR-20a-5p facilitates BMSC chondrogenic differentiation and contributes to cartilage repair in OA by suppressing Map3k2.

In order to study the influence of various structural dimensions of the suspension floor locking mechanism on the vehicle protection performance of the special vehicle suspension floor, the finite element simulation analysis and structural optimization design of the locking mechanism are carried out. The starting load of the locking mechanism based on the occupant damage threshold was determined, the dynamic tensile loading system of the locking mechanism was designed, the accuracy of the design scheme and the finite element model was verified, and the experimental design was carried out using Latin hypercube sampling. In addition, the sensitivity analysis was carried out, the relationship between the structural size of the locking mechanism and the protective performance of the vehicle was clarified, the optimal mathematical model of the locking mechanism was established, and the Pareto solution set of the optimization model was obtained through the multi-objective genetic algorithm. The optimal design scheme of the locking mechanism was obtained by using the linear multi-criterion decision method, and the accuracy of the optimal scheme was verified by the simulation.

A series of experiments have been performed to investigate thermal stratification induced by steam-air mixture vertical injection, in the range of steam mass flux 3–30 kg/m2s, air mass fraction 0–5% and submergence depth 100–300 mm. Experimental results show that: thermal stratification occurs at the region where none of chugging-induced synthetic jets, steam-driven negative buoyancy jets and plume is strong enough. For pure steam experiments, thermal stratification occurs when the steam mass flux above 15 kg/m2s. The pool is mixed well firstly, then thermally stratified, and then re-mixed in sequence, as the water temperature increases. A little air can make thermal stratification and re-mixing occur ahead of time and more air can completely remove thermal stratification. Gas bypass induced by shallow submergence depth makes thermal stratification occur earlier and more severe. The submergence depth has little effect on thermal stratification in chugging regime.

Steam jet condensation is of great importance to pressure suppression containment and automatic depressurization system in nuclear power plant. In this paper, the condensation processes of sonic steam jet in a quiescent subcooled pool are recorded and analyzed, more precise understanding are got in direct contact condensation. Experiments are conducted at atmospheric pressure, and the steam is injected into the subcooled water pool through a vertical nozzle with the inner diameter of 10 mm, water temperature in the range of 25–60 °C and mass velocity in the range of 320–1080 kg/m2s. Richardson number is calculated based on the conservation of momentum for single water jet and its values are in the range of 0.16–2.67. There is no thermal stratification observed in the water pool. Four condensation regimes are observed, including condensation oscillation, contraction, expansion-contraction and double expansion-contraction shapes. A condensation regime map is present based on steam mass velocity and water temperature. The dimensionless steam plume length increase with the increase of steam mass velocity and water temperature, and its values are in the range of 1.4–9.0. Condensation heat transfer coefficient decreases with the increase of steam mass velocity and water temperature, and its values are in the range of 1.44–3.65 MW/m2°C. New more accurate semi-empirical correlations for prediction of the dimensionless steam plume length and condensation heat transfer coefficient are proposed respectively. The discrepancy of predicted plume length is within ± 10% for present experimental results and ± 25% for previous researchers. The discrepancy of predicted condensation heat transfer coefficient is with ± 12%. Keywords: Direct contact condensation, Sonic jet, Condensation regimes, Condensation heat transfer coefficients

A new N-terminal protection/purification handle (PPH), which contained a His6 tag for purification and a photo-cleavable linker, facilitates the efficient synthesis of large proteins with tandem repeats., Proteins with tandem repeats have essential physical or biological roles in cells and have been widely investigated as biomaterials or vaccines. Chemically derived proteins with tandem repeats would be beneficial for research, owing to their accurate structures, possibly with precise modifications, produced by chemical synthesis. Traditional protein synthesis often leads to severe handling loss due to multiple ligations and HPLC purifications. To improve the protein synthesis efficiency, we developed a purification/protection handle consisting of a His6 tag and a photo-labile linker. This handle has great potential to facilitate purification with immobilized metal affinity chromatography techniques and also provides orthogonal protection for N-terminal Cys. The synthesis of the model proteins Muc1 and antifreeze glycoprotein mimics shows that the handle decreases the requirement for HPLC and enables both convergent and sequential assembly of peptide segments.

The bone morphogenetic protein-2 (BMP-2) is an essential regulator of bone formation and remodeling, which has also been implicated in the pathogenesis of osteoarthritis and its closely related chondrocyte senescence. The BMP-2 uses a conformational wrist epitope and a linear knuckle epitope to interact with type-I (BMPR-I) and type-II (BMPR-II) receptors, respectively. Previously, the knuckle epitope has been intensely studied, but the wrist epitope still remains largely unexplored due to its discontinuous nature. In the present work, the intermolecular interaction of BMP-2 with BMPR-I was investigated systematically at structural, energetic and dynamic levels. Three discrete hotspots that represent the key BMPR-I recognition sites of BMP-2 were identified; they are spatially dispersed over the two monomers of BMP-2 dimer and totally account for 83.5 % binding potency of BMP-2 to BMPR-I (hotspot 1: residues 49-70 in monomer 1; hotspot 2: residues 24-31 in monomer 2; hotspot 3: residues 88-107 in monomer 2). Therefore, we defined the three discrete hotspot sites as the core region of wrist epitope; their contribution to the binding increases in the order: hotspot 2 hotspot 3 hotspot 1. We demonstrated that the primary hotspot 1 site has a native U-shaped conformation in the full-length BMP-2 protein context, but it cannot maintain in the native conformation when split from the context to obtain a free hotspot-1 peptide, thus largely impairing its binding potency to BMPR-I. We further employed disulfide-bonded cyclization and head-to-tail cyclization to constrain the peptide conformation, and found that only the former can effectively constrain the peptide into native conformation, thus considerably improving its binding affinity to BMPR-I, whereas the latter totally disorders the native conformation, thus rendering the peptide as a full nonbinder of BMPR-I.

Introduction: Synthetic fibrous membranes unveil a promising field in anti-adhesion of tendons. Meanwhile, oriented nanofiber structures have been widely studied and used in the application of biomedical engineering, particularly in repairing and strengthening effects. Methods: In this study, a bi-layer poly(L-lactic acid) (PLLA) electrospun membrane was fabricated, in which the inner oriented fibrous layer was designed to promote tendon healing while outer random aligned layer was designed to prevent peritendinous adhesion. Results: It was found that fibroblasts were aligned along the oriented fiber of membranes in vitro and in a Leghorn chicken model. In biomechanical tests of repaired tendons, no significant difference was found between oriented fibrous membrane and blank control in maximum tensile strength; both oriented fibrous membranes and random fibrous membranes showed lower work of flexion than blank control, which was consistent with gross assessment. Conclusion: It was practicable to promote tendon healing while preventing adhesion via bi-layer PLLA membranes with an inner-oriented-fiber fabricated structure.

Bone morphogenetic protein-2 (BMP-2) is a key regulator of bone formation, growth and regeneration, which contains a conformational wrist epitope and a linear knuckle epitope that are functionally responsible for the protein by mediating its interaction with type-I and type-II receptors, respectively. Previously, a long (19-mer) knuckle peptide derived from the knuckle epitope region (residues 73-92) has been found to promote osteogenesis and bone repair. Here, we attempt to rationally redesign the knuckle peptide by using bioinformatics and machine learning-guided evolution to obtain structurally simplified, potent osteogenic peptides that are capable of targeting type-II receptor. Complex analysis reveals that only a fraction of the epitope region can directly interact with type-II receptor, which represents a small (12-mer) knuckle-derived peptide (KDP0 peptide). Glycine scanning further identifies three KDP0 anchor residues Ser88, Leu90 and Tyr91 that are fundamentally important in the peptide-receptor binding. Systematic mutation, amino acid combination and uniform design of other nine KDP0 non-anchor residues generate 32 new knuckle-derived peptides (KDP1-KDP32); their binding affinities to recombinant protein of human type-II receptor are determined using fluorescence spectroscopy assay. The resulting affinity values (Kd) are used to train six regression models developed by combination of two machine learning methods and three amino acids descriptors. The best SVM/VHSE predictor is then utilised to guide the genetic evolution of a knuckle-derived peptide population. Eight peptides (KDP33-KDP40) with high affinity scores are selected from the improved population, and their osteogenic activities on bone marrow stromal cells are measured using alkaline phosphatase assay. Consequently, six out of the 8 tested peptides exhibit increased activity relative to KDP0 peptide. The KDP34 (DFQTWSFLYVEN) is found as the most potent peptide with APL activities of 195% and 279% at 0.01 and 0.1 µg/ml, respectively, which shares a similar binding mode with the native knuckle epitope and can form diverse nonbonded interactions of hydrogen bond, hydrophobic contact, cation-π/π-π stacking and salt bridge with type-II receptor.

Rheumatoid arthritis commonly causes transient limitation of joint motion, but the treatment of persistent stiffness in the rheumatoid elbow has rarely been reported. The purpose of this study was to evaluate the long-term clinical results of surgical treatment of rheumatoid elbow stiffness.Surgical treatment, including open arthrolysis with hinged external fixation, total synovectomy, and ulnar nerve release and anteriorization, was performed in 48 elbows in 43 patients with rheumatoid arthritis and early joint destruction. Mobility (flexion-extension and pronation-supination), Mayo Elbow Performance Score (MEPS), visual analog scale (VAS) score, muscle strength, nerve symptoms, postoperative complications, and recurrent synovitis were evaluated 9-11 years (average, 9.88 years) postoperatively.The mobility of the elbow was significantly improved over the preoperative period either in extension, flexion, protonation, supination (P .001, P .001, P .001, P = .002). The mean MEPS was significantly improved from 56.25 points (range, 30-90) to 87.40 points (range, 40-100) (P .001). The pain was relieved, and the mean VAS score was reduced from 3.56 (range, 0-8) to 1.08 (range, 0-5) points (P .001). Preoperative ulnar nerve symptoms were observed in 17 patients and relieved in 10 (59%) patients, and the mean Amadio score was raised from 6.9 (range, 3-9) to 7.96 (range, 4-9) points (P .001). Through surgical treatment and postoperative rehabilitation, the mean grip strength of the patients was significantly improved from an average of 9.01 (range, 3.4-18.5) to 17.56 kg (range, 3.9-40.2) (P .001). Five elbows developed recurrent synovitis, and one underwent total elbow arthroplasty. Postoperative complications were uncommon and not severe.Surgical treatment is a reliable procedure for rheumatoid elbow stiffness and can be effective in improving elbow mobility, function, muscle strength, pain relief, and relief of nerve symptoms.

Background Open elbow arthrolysis manipulates tendons and soft tissues surrounding the elbow and may lead to strength decline after the operation. We hypothesized that strength of elbow and wrist motions and handgrip could be compromised after the procedure and that the strength recovery pattern may differ between men and women and between the dominant and nondominant side. Methods This was a prospective cohort study. We monitored 32 patients with post-traumatic elbow stiffness who underwent open arthrolysis between June 2014 and December 2014. All patients underwent standardized postoperative physical therapy. Preoperative and postoperative isometric strength were measured by a handheld dynamometer. Mayo Elbow Performance Score (MEPS) and arc of motion (AOM) were also analyzed. Results Mean follow-up was 26.13 months. Significant improvement was noticed in mean AOM (from 46° to 127°) and MEPS (from 67.97 to 96.86). No significant decline was noted in isometric strength at the last follow-up day. The strength ratios between men and women showed no significant difference from postoperative day 7 to the last follow-up day. At all follow-up assessments, isometric strength showed no significant difference between the dominant and nondominant side. Conclusions AOM and MEPS achieved significant enhancement after open elbow arthrolysis. The procedure did not lead to isometric strength decline. Postoperative gain of strength was proportional to the baseline strength level of each muscle group, and men had a more prominent gain of strength than women during the entire follow-up. Dominance had no effect on postoperative strength recovery.

Heterotopic ossification (HO) may lead to complete elbow ankylosis, resulting in severe disability. The prognostic factors that may be valuable in guiding treatment of this condition have not yet been evaluated. The goals of this study were to describe the outcomes of open release for ankylosed elbow caused by HO and to analyse factors associated with clinical outcomes. This retrospective study assessed 41 patients with ankylosed elbows treated by open release surgery. We report final clinical outcomes and analyses of the association between outcomes and clinical variables. Mean patient age was 36.4 years; follow-up was 36.1 months. Mean arc of motion increased from 0 to 112° post-operatively, mean pronation from 34 to 52°, supination from a mean of 51 to 76°, and Mean Mayo Elbow Performance Score (MEPS) from 42.8 to 84.2. Eight patients experienced recurrence, two of whom underwent a second operation: one for elbow instability and one for revision surgery. Linear regression analysis demonstrated that initial injury type (p = 0.020), articular surface damage (p = 0.001), coma iduringthe initial injury (p = 0.001) and concomitant radial head replacement (p = 0.029) were independent factors affecting the final MEPS. Satisfactory outcomes were achieved, indicating that open release is effective for ankylosed elbows. Our findings demonstrated that initial injury type, articular surface damage, coma and radial head replacement are outcome predictors affecting final outcomes.

The purpose of this study was to compare different grades of elbow stiffness and investigate demographic, injury, and treatment factors potentially associated with the development of severe elbow stiffness. We performed a retrospective study involving 169 patients with post-traumatic elbow stiffness between June 2014 and June 2016. Patient demographics, injury, and treatment details were reviewed. Patients were classified into three groups according to the elbow motion. Ordinal regression analyses were performed to examine the independent factors. Patients were classified into: mild (49 patients), moderate (59 patients), and severe (61 patients) groups. Patients with severe stiffness had a significantly worse elbow functional performance. Univariate ordinal regression revealed that severe elbow stiffness was associated with high-energy injury (odds ratio [OR] 4.73), olecranon fracture (OR 1.92), fracture-dislocation (OR 2.28), and open fracture (OR 3.24). Multivariate regression showed that higher-energy injuries were associated with severe stiffness (OR 4.45, p = 0.003). Elbow stiffness after fracture surgery often results in joint stiffness. Severe stiffness often resulted in more significant functional impairment. Our study suggested that high-energy injuries were associated with the development of severe elbow stiffness.

Hypothesis The purpose of this study was to determine the effect of a long duration of elbow stiffness on functional outcomes and complications after arthrolysis. Methods Participants included consecutive patients with a long duration of elbow stiffness (≥5 years, n = 23) and control patients matched for age, sex, and initial injury type (n = 46). All patients underwent elbow arthrolysis combined with hinged external fixation between March 2014 and March 2016. At baseline and follow-up, we evaluated elbow motion (flexion, extension, supination, pronation, and range of motion) and patient-reported outcomes, including the Mayo Elbow Performance Score (MEPS) and visual analog scale for pain. Postoperative complications including infection, nerve dysfunction, and instability were recorded. Results There were no significant differences in preoperative elbow pain, range of motion, or MEPS between groups. Postoperatively, pronation and the MEPS in patients with a long disease duration were inferior to those in control patients (P = .041 and P = .016, respectively). Patients with a long disease duration also had a significantly higher incidence of complications than control patients (P = .002). At final follow-up, 7 patients (30%) in the long disease duration group and 3 patients (7%) in the control group presented with nerve symptoms (P = .022). Conclusions A long duration of elbow stiffness may negatively influence functional outcomes and increase the risk of complications after arthrolysis.

The purpose of this study was to evaluate the results of our protocol that include the restoration of mobility using open release combined with external fixation and stability using ligament repair, to determine the optimal timing of surgery, and to investigate whether resection and replacement of the radial head are associated with different outcomes. Twenty-six patients with elbow stiffness after operation of terrible triad injury of the elbow were treated with our protocol. We assessed the optimal timing of the operation by comparing outcomes between the early treatment group and the delayed treatment group. The comparison was performed to investigate whether the results differed between resection and replacement of the radial head. Stability of the elbow, range of motion (ROM), Mayo Elbow Performance Score (MEPS), and complications were assessed for each patient. The mean interval from the initial surgery to the index procedure was 13 months, and the mean follow-up period was 29 months. The MEPS increased from a mean of 65 points to 94 points. Twenty-five of 26 patients achieved stability of the elbow, and all patients achieved functional ROM. There were no significant differences between the two subgroups with respect to ROM and stability of the elbow. Our protocol can restore mobility and stability. Resection and replacement of the radial head are both feasible using this protocol. Lastly, the timing of the surgery was not very rigorous, and the surgical delay may be insignificant. Level IV; Case Series; Treatment Study.

Background Being overweight has become a serious public health concern in China. Higher body mass index has been proven to be associated with poor outcome after orthopedic surgery. The purpose of this study was to examine the effect of being overweight on functional outcomes and complications after open arthrolysis for post-traumatic elbow stiffness. Methods We performed a retrospective study including 122 patients with post-traumatic elbow stiffness undergoing arthrolysis, including 84 in the normal weight group and 38 in the overweight group. Demographic data, surgical data, and data on preoperative and postoperative functional performance and complications were obtained. Results Demographic data and disease characteristics were comparable between the 2 groups at baseline. All patients showed significant improvement after elbow arthrolysis. Postoperatively, the range of motion and Mayo Elbow Performance Score of the normal weight group were significantly better than those of the overweight group. Sixteen patients developed postoperative complications. No significant differences in complication rates between the 2 groups were found. Conclusions Most patients showed satisfactory functional outcomes after arthrolysis. The postoperative functional outcomes of the overweight group were inferior to those of the normal weight group to a certain extent. This study underlines the importance of detailed rehabilitation instructions in patients with higher body mass index.

To explore the effectiveness and safety of open arthrolysis combined with internal fixator removal for post-traumatic elbow stiffness.A retrospective analysis was made on the data of 80 cases treated by open arthrolysis for elbow stiffness between January 2010 and December 2011. The patients were divided into 2 groups: no internal fixation group (group A, n = 39) and internal fixation group (group B, n = 41) according to whether they underwent internal fixator removal at the same time. No significant difference was found in age, gender, affected side, injury time, elbow rigidity grade, and severity of heterotopic ossification (HO) between 2 groups (P0.05) except for original injury type (P0.05). The effectiveness was evaluated by the occurrence of complications including ulnar nerve symptoms, HO recurrence and re-fracture, the elbow range of motion (ROM) and the Mayo elbow performance score (MEPS).The mean follow-up duration was 15.7 months (range, 12-18 months) in group A and 16.1 months (range, 12-20 months) in group B. Ulnar nerve symptoms in 5 cases (12.8%) and HO reccurrence in 1 case (2.6%) occurred in group A, while ulnar nerve symptoms in 4 cases (9.8%), HO recurrence 1 case (2.4%), and refracture in 1 case (2.4%) occurred in group B. The incidence of each complication showed no significant difference between 2 groups (P0.05). Both the ROM and the MEPS at last follow-up increased significantly when compared with preoperative ones in 2 groups (P0.05). Besides, MEPS of group A was significantly higher than that of group B (t = 2.36, P = 0.02), but no significant difference was found in the ROM between 2 groups at last follow-up (t = 0.40, P = 0.69). Based on MEPS, the results were excellent in 16 cases, good in 16 cases, fair in 6 cases, and poor in 1 case in group A with an excellent and good rate of 82.1%; the results were excellent in 10 cases, good in 25 cases, fair in 4 cases, and poor in 2 cases in group B with an excellent and good rate of 85.4%. There was no significant difference in excellent and good rate between 2 groups (χ2 = 0.16, P = 0.69).Open elbow arthrolysis combined with internal fixator removal for post-traumatic elbow stiffness is safe and effective. However, measures for prevention of re-fracture should always be taken into consideration.