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Objective Early articular cartilage lesion (CL) is a vital sign in the onset of posttraumatic knee osteoarthritis (PTOA) in patients with anterior cruciate ligament deficiency (ACLD). Researchers have suggested that altered kinematics could accelerate CLs and, therefore, lead to the onset of PTOA. However, little is known about whether specific knee kinematics exist that lead to early CL in chronic ACLD knees. Level walking is the most frequent and relevant in vivo activity, which greatly impacts knee health. We hypothesized that the knee kinematics during level walking in chronic ACLD knees with early tibiofemoral CL would significantly differ from those of chronic ACLD knees without early tibiofemoral CL. Methods Thirty patients with a chronic ACLD history, including 18 subjects with CLs and 12 subjects without CLs, and 35 healthy control subjects were recruited for the study from July 2020 to August 2022. The knee kinematic data during level walking were collected using a three‐dimensional motion analysis system. The kinematic differences between groups were compared using statistical parametric mapping with one dimension for One‐Way ANOVA. The cartilage statuses of the ACLD knees were assessed via MRI examination. The CLs distribution of subjects was evaluated using a modified Noyes scale and analyzed by chi‐square tests. Results ACLD knees with CLs had significantly greater posterior tibial translation (7.7–8.0mm, 12%–18% gait cycle GC, p = 0.014) compared to ACLD knees without CLs during level walking. ACLD knees with CLs had greater posterior tibial translation (4.6–5.5mm, 0%–23% GC, p

Objective Knee kinematic asymmetries after anterior cruciate ligament reconstruction (ACLR) are correlated with poor clinical outcomes, such as the progression of knee cartilage degenerations or reinjuries. Fast walking in patients with knee conditions may exacerbate knee kinematic asymmetries, but its impact on ACLR patients is uncertain. The aim of this study is to investigate if fast walking induces more knee kinematic asymmetries in unilateral ACLR patients. Methods This cross‐sectional study enrolled 55 patients with unilateral ACLR from January 2020 to July 2022. There were 48 males and seven females with an average age of 30.6 ± 6.4 years. Knee kinematic data were collected at three walking speeds: self‐selected, fast (150% normal), and slow (50% normal). A 3D knee kinematic analysis system measured the data, and self‐reported outcomes assessed comfort levels during walking. We used SPM1D for two‐way repeated ANOVA and posthoc paired t‐tests to analyze kinematic differences in groups. Results In fast walking, ACLR knees exhibited more transverse kinematic asymmetries than intact knees, including greater external rotation angle (1.8°, 38%–43%; gait cycle [GC], p

Purpose The objective was to describe the technique and clinical outcome of microwave thermal ablation (MWA) and perfusion combined with synthetic bone substitutes in treating unicameral bone cysts (UBCs) in adolescents.Materials and Methods A total of 14 consecutive patients were enrolled by percutaneous MWA and saline irrigation combined with synthetic bone substitutes. Clinical follow-up included the assessment of pain, swelling, and functional mobility. Radiological parameters included tumor volume, physis-cyst distance, cortical thickness of the thinnest cortical bone, and the Modified Neer classification system.Results The mean follow-up was 28.9 months (26–52 months). All UBCs were primary, and all patients underwent the MWA, saline perfusion, and reconstruction combined with a synthetic bone substitute session, except for one patient (7.1%) who required a second session. All patients had good clinical results at the final follow-up. Satisfactory cyst healing was achieved in 13 cases according to radiological parameters. Tumor volume decreased from a mean of 49.7 cm3 before surgery treatment to 13.9 cm3 at the final follow-up (p

This network meta‐analysis aims to evaluate the comparative effectiveness and safety of suture anchors (SA), tendon grafts (TG), hook plates (HP), Tight‐Rope (TR), and EndoButton (EB) in the treatment of acute acromioclavicular joint (ACJ) dislocation. The Embase, PubMed, and Web of Science databases were searched from their inception date to June 3, 2022. Studies included all eligible randomized controlled trials (RCTs) and cohort studies with the comparison of five different fixation systems among SA, TG, HP, TR, and EB were identified. All studies were reviewed, performed data extraction, and assessed the risk of bias independently by two reviewers. The primary outcomes are Constant–Murley score (CMS) improvement for assessing clinical efficacy, and complications. The second outcomes are visual analog scale (VAS) for assessing pain relief and the coracoclavicular distance (CCD) for assessing postoperative joint reduction. Version 2 of the revised Cochrane risk of bias tool for randomized trials (RoB 2) and the risk of bias in nonrandomized studies of interventions (ROBINS‐I) were used to assess the RCTs and non‐randomized trials, respectively. The continuous outcomes were presented as mean differences (MD), and risk ratios (OR) were used for dichotomous outcomes, both with 95% confidence intervals (CI). Surface under the cumulative ranking curves (SUCRA) results were calculated to offer a ranking of each intervention. We identified 31 eligible trials, including 1687 patients in total. HP showed less CMS improvement than TR and EB in both the Network Meta‐analysis (NMA) and pairwise meta‐analysis. HP also showed less CMS improvement than SA in NMA. For pain relief, HP performed worse than TR both in pairwise meta‐analysis and NMA. No significant differences were found for the measured value of CCD. Both TR and EB showed a lower incidence of complications than HP in pairwise meta‐analysis. The rank of SUCRA for CMS improvement was as follows: SA, TR, EB, TG, and HP; for pain relief: TR, EB, TG, SA, and HP; for CCD: HP, TR, SA, EB, and TG. For complications, HP showed the highest rank, followed by TG, EB, TR, and SA. SA shows better clinical effectiveness and reliable safety in the treatment of acute ACJ dislocation. Although HP is the most widely used surgical option currently, it should be carefully taken into consideration for its high incidence of complications.

Abstract Objective To investigate the clinical usefulness of serum superoxide dismutase (SOD) measurement in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Methods In this single-center retrospective study, demographic data, serum SOD levels, erythrocyte sedimentation rate (ESR), C reactive protein (CRP), the Birmingham Vasculitis Activity Score (BVAS), ANCA, organ involvement, and outcomes were analyzed for 152 AAV patients hospitalized in the Second Affiliated Hospital of Chongqing Medical University. Meanwhile, the serum SOD levels of 150 healthy people were collected as the control group. Results Compared to the healthy control group, serum SOD levels of the AAV group were significantly lower (P

Rare earth elements (REEs) have been long applied in magnesium alloys, among which the mischmetal-containing WE43 alloy has already got the CE mark approval for clinical application. A considerable amount of REEs (7 wt%) is needed in that multi-phased alloy to achieve a good combination of mechanical strength and corrosion resistance. However, the high complex RE addition accompanied with multiple second phases may bring the concern of biological hazards. Single-phased Mg-RE alloys with simpler compositions were proposed to improve the overall performance, i.e., “Simpler alloy, better performance”. The single-phased microstructure can be successfully obtained with typical high-solubility REEs (Ho, Er or Lu) through traditional smelting, casting and extrusion in a wide compositional range. A good corrosion resistance with a macroscopically uniform corrosion mode was guaranteed by the homogeneously single-phased microstructure. The bimodal-grained structure with plenty of sub-grain microstructures allow us to minimize the RE addition to

Objective Patellofemoral kinematics and contact mechanics are important measurements for the assessment of patellofemoral joint (PFJ) problems. Simultaneously measuring PFJ contact pressures and kinematics is a challenging task. The purpose of this study was to simultaneously measure the kinematics and mean/peak contact pressures in the PFJs of cadaveric knees. Methods This was a comparative study performed on fresh cadaveric knees. The kinematic data was acquired for nine cadaveric knees using an optical tracking system. Data about the contact pressure and contact area in the PFJ was obtained at knee flexion angles of 0°, 30°, 60°, 90°, and 120° using a pressure sensor. Intraclass correlation coefficients (ICCs) and minimal detectable differences (MDDs) of six degrees of freedom (6 DOF) in the PFJs were calculated. ICCs and the MDDs of contact pressure, peak pressure, and contact area in the PFJs were also analyzed. We also compared the kinematics of the cadaveric knees before and after the insertion of the pressure sensor. Results All ICC values of 6 DOF in the PFJs were found to be greater than or equal to 0.924. Regarding medial–lateral rotation, the patellar showed a simplified movement pattern that demonstrated progressive lateral rotation of 4.8° ± 3.4° at 120° of knee flexion. While for patellar tilting, the patella showed medial tilting that peaked at 7.2 ± 2.5° at 30° of knee flexion. Whereas no significant differences in PFJ kinematics were found between with and without the placement of the pressure sensor at all knee flexions (P > 0.05). Most of the ICC values for contact pressure, peak contact pressure, and contact area ranged from 0.8 to 0.9. The MDDs for rotational displacement were 0.9° and 0.6 mm for translational displacement. No statistical differences in patellar kinematics were found before and after the insertion of the pressure sensor. Conclusions The setup in the present study enables researchers to simultaneously and synchronously collect real‐time PFJ kinematics and tibiofemoral joint (TFJ) biomechanical kinematic data with high reliability. The low MDDs enabled the researchers to obtain an accurate interpretation of the kinematic and contact mechanics measurement using the experimental setting used in the present study.

Objective To investigate the clinical effects of microwave ablation (MWA) in addition to open surgery for the treatment of lung cancer‐derived thoracolumbar metastases. Methods This was a single‐institution, retrospective, cohort study. From January 2019 to December 2020, a total of 47 patients with lung cancer‐derived thoracolumbar metastases underwent posterior spinal canal decompression and fixation surgery in our hospital. Two independent surgical teams treated these patients. One group underwent open surgery combined with MWA therapy, while the other had open surgery only (control). The pre‐ and post‐operative visual analog scale (VAS) scores and the overall survival (OS) were compared between the MWA and control groups. The Frankel Grade classification was applied for the evaluation of the post‐surgical spinal cord function. Improvement was defined as an increase of at least one rank from the pre‐operative scores. Each patient was evaluated pre‐ and post‐operatively at 48 h, 1 month, and 3‐month intervals. Data on surgical‐related complications were recorded. Results Thirty men and 17 women were included, with an average age of 57.9 ± 11.4 years (range, 26–81 years). Twenty‐eight patients underwent MWA and were in the MWA group, and 19 patients were included in the control group. Post‐operatively all patients were followed up regularly; the median follow‐up time was 12 months (range, 3–24 months), and their median OS was 14 months. Patients in the MWA group had a lower VAS score than those in the control group at the 48‐h (1.75 ± 1.01 vs 2.47 ± 0.96, P = 0.01) and 1‐month (1.79 ± 0.92 vs 2.53 ± 1.35, P = 0.048) check‐ups. At the 3‐month evaluation, the VAS score differences between the two groups were not significant (P = 0.133). After surgery, spinal cord function improvement was not significantly different between the MWA and control groups (P = 0.515). MWA therapy combined with open surgery was not associated with increased OS compared with the control group (P = 0.492). Conclusion MWA can be an effective and safe pain‐relief method but may not extend the OS of patients with lung cancer.

BackgroundPrevious studies have shown that systemic inflammation indicators could predict the survival outcomes of patients with malignant tumors receiving various treatments. Radiotherapy, as a crucial treatment modality, effectively alleviates discomfort in patients with bone metastasis (BM) and greatly improves the quality of life for them. This study aimed to investigate the prognostic value of systemic inflammation index in hepatocellular carcinoma (HCC) patients with BM treated with radiotherapy.MethodsWe retrospectively analyzed clinical data collected from HCC patients with BM who received radiotherapy in our institution between January 2017 and December 2021. The pre-treatment neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) were derived to determine their relationship with overall survival (OS) and progression-free survival (PFS), using the Kaplan-Meier survival curves. The optimal cut-off value of the systemic inflammation indicators for predicting prognosis was assessed by receiver operating characteristic (ROC) curves. Univariate and multivariate analyses were performed to ultimately evaluate the factors associated with survival.ResultsThe study included 239 patients with a median 14-month follow-up. The median OS was 18 months (95% confidence interval [CI] = 12.0-24.0) and the median PFS was 8.5 months (95% CI = 6.5-9.5). The optimal cut-off values for the patients were determined by ROC curve analysis as follows: SII =395.05, NLR=5.43 and PLR = 108.23. The area under the receiver operating characteristic curve values for SII, NLR and PLR in disease control prediction were 0.750, 0.665 and 0.676, respectively. Elevated systemic immune-inflammation index (SII>395.05) and higher NLR (NLR>5.43) were independently associated with poor OS and PFS. In multivariate analysis, Child-Pugh class (P = 0.038), intrahepatic tumor controlled (P = 0.019), SII (P = 0.001) and NLR (P = 0.007) were independent prognostic factors of OS and Child-Pugh class (P = 0.042), SII (P < 0.001) and NLR (P = 0.002) were independently correlated with PFS.ConclusionNLR and SII were associated with poor prognosis in HCC patients with BM receiving radiotherapy and might be considered reliable and independent prognostic biomarkers for HCC patients with BM.

Abstract Purpose To determine the repair of LMPR lesions would improve the ACL graft maturation. Method A total of 49 patients underwent ACL reconstruction were included in this study. Patients were furtherly sub-grouped according to the status of LMPR: intact (17), repair (16) and resected (16). Assessments performed pre- and 2 years post-operatively included patients-reported scores and arthrometer side-to-side difference. Magnetic resonance imaging was used 2 years after the surgery to compare the lateral meniscal extrusion (LME), anterior tibial subluxation of the medial compartment (ATSMC), anterior tibial subluxation of the lateral compartment (ATSLC), the difference of ATSMC and ATSLC, and signal/noise quotient (SNQ) of ACL graft. Results In LMPR resected group, it showed greater post-operative ATSMC-ATSLC difference when compared with pre-operatively (P = 0.006) and with the other 2 groups (intact: P = 0.031; repair: P = 0.048). SNQ of ACL graft was higher in LMPR resected group than those in LMPR intact (P = 0.004) and repair group (P = 0.002). The LMPR repair group showed significant reduction in LME post-operatively (P = 0.001). Post-operative measures on ATSLC-ATSMC difference (β = 0.304, P = 0.049) and LME (β = 0.492, P = 0.003) showed significant association with graft SNQ. Conclusions Transtibial repair of LMPR concomitant with ACL reconstruction restored translational stability, reduced meniscus extrusion, making it beneficial for ACL graft maturation.

Anterior cruciate ligament deficiency (ACLD) is often accompanied by concomitant meniscal tears. The study aimed to assess the kinematic alterations of patellofemoral joint (PFJ) in anterior cruciate ligament deficiency knees with or without meniscal tears during a single-leg lunge. Sixty unilateral anterior cruciate ligament deficiency patients were recruited for the study, including 15 isolated anterior cruciate ligament deficiency patients (group 1), 15 anterior cruciate ligament deficiency patients with medial meniscal tears (group 2), 15 patients with lateral meniscal tears (group 3) and 15 patients with combined medial/lateral meniscal tears (group 4). The patellofemoral joint kinematics were determined by a single fluoroscopic image system. Patellofemoral joint kinematics of contralateral anterior cruciate ligament-intact (ACLI) and anterior cruciate ligament deficiency knees were compared. With or without meniscal tears, anterior cruciate ligament deficiency knees had significantly smaller patellar flexion than the anterior cruciate ligament-intact knees (∼5°–10°; p < 0.05). anterior cruciate ligament deficiency knees had more patellar lateral tilting by approximately 1°–2° than the anterior cruciate ligament-intact knees (p < 0.05) in groups 2, 3, and 4. anterior cruciate ligament deficiency groups with medial meniscal deficiencies showed consistent increased lateral patellar translations (2–4 mm) compared to the anterior cruciate ligament-intact group during a single-leg lunge. The results indicate that meniscal tears alter anterior cruciate ligament deficiency patients’ patellofemoral joint kinematics and the types of the meniscal injuries also affect the patellofemoral joint kinematics. Considering the varying effects of meniscal tears on the patellofemoral joint kinematics, specific treatments for anterior cruciate ligament deficiency patients with meniscal tears should be proposed in some closed kinetic chain (CKC) exercise programs, such as single-leg lunge.

Introduction Generalized joint hypermobility (GJH) is a hereditary connective tissue disease in which the range of motion (ROM) of multiple joints exceeds the normal range, and the ROM varies with age, gender, and ethnicity. At present, the six-degree-of-freedom (6-DOF) of ankle kinematics among people with GJH have not been studied. To investigate the kinematic characteristics in the ankle during treadmill gait of university students with generalized joint hypermobility compared to normal participants. We hypothesized that compared to the participants in the control group, those with GJH would exhibit kinematic characteristics of poorer active motion stability in the ankle during treadmill gait. Methods Healthy university student volunteers aged 18–24 (excluding those with a history of ankle trauma, etc.) were recruited and divided into a control group (50 volunteers) and a GJH group (Beighton score ≥4, 50 volunteers). Data of the 6-DOF kinematics of ankle was collected using a 3D gait analysis system. Variables were evaluated using independent t-tests and Wilcoxon signed-rank tests. Results In the proximal/distal parameter, proximal displacement was significantly increased in the GJH group compared with the control group during 4–9% and 96–97% of the gait phase (loading response and terminal swing phase), with an increase of (0.1–0.2 cm, p < .05). Regarding the proximal/distal, internal/external, plantarflexion/dorsiflexion, and anterior/posterior parameters, the participants with GJH exhibited greater ROM than those in the control group throughout the gait cycle (0.24 ± 0.22 cm vs. 0.19 ± 0.15 cm, p = 0.047, 5.56 ± 2.90° vs. 4.48 ± 3.30°, p = .020, 23.05 ± 5.75° vs. 20.36 ± 4.91°, p < .001, 0.65 ± 0.30 cm vs. 0.55 ± 0.27 cm, p = .018). However, ROM of inversion/eversion translation was found to be decreased in the GJH group compared to the control group (8.92 ± 1.59° vs. 9.47 ± 1.37°, p = .009). In addition, there was no statistical difference between the GJH group and the control group in ROM of medial/lateral translation (0.05 ± 0.06 cm vs. 0.04 ± 0.05 cm, p = .131). Conclusion Our results confirm that our hypothesis is not valid. Although there were a few differences in each gait parameter of the ankle between the GJH group and the control group, the difference was not significant. These results indicate that the presence of GJH has less effect on ankle kinematics and enhance our knowledge of the relationship between GJH and 6-DOF of ankle kinematics.

Whether load carriage leads to six-degrees-of-freedom (6DOF) knee kinematic alterations remains unclear. Exploring this mechanism may reveal meaningful knee kinematic information that can be used to improve load carriage conditions, the design of protective devices, and the knowledge of the effects of load carriage on knees. We recruited 44 subjects to explore kinematic alterations from an unloaded state to 60% bodyweight (BW) load carriage. A three-dimensional gait analysis system was used to collect the knee kinematic data. One-way repeated analysis of variance (ANOVA) was used to explore the effects of load levels on knee kinematics. The effects of increasing load levels on knee kinematics were smooth with decreased or increased trends. We found that knees significantly exhibited increased lateral tibial translation (up to 1.2 mm), knee flexion angle (up to 1.4°), internal tibial rotation (up to 1.3°), and tibial proximal translation (up to 1.0 mm) when they went from an unloaded state to 60%BW load carriage during the stance phase (p < 0.05). Significant small knee adduction/abduction angle and posterior tibial translation alterations (

Abstract Background The Opti_Knee system, a marker-based motion capture system, tracks and analyzes the 6 degrees of freedom (6DOF) motion of the knee joint. However, the validation of the accuracy of this gait system had not been previously reported. The objective of this study was to validate and the system. Two healthy subjects were recruited for the study. Methods The 6DOF kinematics of the knee during flexion–extension and level walking cycles of the knee were recorded by Opti_Knee and compared to those from a biplanar fluoroscopy system. The root mean square error (RMSE) of knee kinematics in flexion–extension cycles were compared between the two systems to validate the accuracy at which they detect basic knee motions. The RMSE of kinematics at key events of gait cycles (level walking) were compared to validate the accuracy at which the systems detect functional knee motion. Pearson correlation tests were conducted to assess similarities in knee kinematic trends between the two systems. Results In flexion–extension cycles, the average translational accuracy (RMSE) was between 2.7 and 3.7 mm and the average rotational accuracy was between 1.7 and 3.8°. The Pearson correlation of coefficients for flexion–extension cycles was between 0.858 and 0.994 for translation and 0.995-0.999 for angles. In gait cycles, the RMSEs of angular knee kinematics were 2.3° for adduction/abduction, 3.2° for internal/external rotation, and 1.4° for flexion/extension. The RMSEs of translational kinematics were 4.2 mm for anterior/posterior translation, 3.3 mm for distal/proximal translation, and 3.2 mm for medial/lateral translation. The Pearson correlation of coefficients values was between 0.964 and 0.999 for angular kinematics and 0.883 and 0.938 for translational kinematics. Conclusion The Opti_Knee gait system exhibited acceptable accuracy and strong correlation strength compared to biplanar fluoroscopy. The Opti _Knee may serve as a promising portable clinical system for dynamic functional assessments of the knee.

Anterior cruciate ligament deficiency (ACLD) patients tend to walk slowly but try to catch up with the speed level of healthy subjects daily. Exploring the effects of the walking speed level of healthy subjects on the ACLD patients’ knee kinematics is important to improving non-operative treatments and delaying the progression of posttraumatic knee osteoarthritis. This study aimed to explore whether healthy controls’ walking speed level leads to additional knee kinematic asymmetries in patients with ACLD. 27 ACLD patients and 29 healthy controls were recruited for the study. The ACLD patients walked at two levels of walking speed, including self-selected and healthy controls’ walking speed levels. A three-dimensional gait analysis system was used to collect their knee kinematic data. ACLD patients exhibited more kinematic asymmetries when walking at healthy controls’ walking speed level than at their self-selected speeds. The kinematic asymmetries included increased posterior tibial translation (4.6 mm) and anteroposterior tibial ROM (3.9 mm), abduction angle (1.5°), and distal tibial translation (3.2 mm) asymmetries (p < 0.05). Our findings are meaningful for developing non-operative treatment strategies for patients with ACLD. To get fewer knee kinematic asymmetries, self-selected walking speed could be suggested for patients with ACLD daily rather than the speed levels of healthy subjects.

Knee osteoarthritis (KOA) is a worldwide disease leading to knee function loss and disorders. However, traditional assessment by X‐ray cannot assess patients’ knee functions and disorders dynamically, making it impossible to achieve a direct functional assessment of KOA. To solve this problem, here it is shown that 3D knee gait parameters could be used to diagnose KOA and guide its therapeutic strategy through direct functional assessment. We employ a total of 1201 participants, and successfully build and validate diagnostic and predictive models for KOA diagnosis and therapeutic strategy using an artificial intelligence (AI)‐based method, logistic regression, a kind of interpretable machine learning. Four diagnostic models are successfully established including angular (AM), translational (TM), composite (CM), and ATCM (a parallel conjoint model of AM, TM, and CM) model with a Youden index of 0.7312, 0.6689, 0.8214, and 0.7492, respectively. The same AI‐based method is also used to develop medical decision classification (MDC) for predicting whether a KOA patient needs operative intervention or not. MDC has a Youden index, sensitivity, and specificity of 0.8886, 92.11%, and 96.75%, respectively. These findings contribute to new knowledge of knee kinematics and KOA diagnosis and represent a new approach to accurate KOA diagnosis and assessment.

Introduction: We previously demonstrated that magnesium ions (Mg2+) was a novel therapeutic alternative for osteoarthritis (OA) through promoting the hypoxia inducible factor-1α (HIF-1α)-mediated cartilage matrix synthesis. However, oxidative stress can inhibit the expression of HIF-1α, amplify the inflammation that potentially impairs the therapeutic efficacy of Mg2+ in OA. Vitamin (VC), a potent antioxidant, may enhance the efficacy of Mg2+ in OA treatment. This study aims to investigate the efficacy of combination of Mg2+ and VC on alleviating joint destruction and pain in OA. Material and methods: Anterior cruciate ligament transection with partial medial meniscectomy induced mice OA model were randomly received intra-articular injection of either saline, MgCl2 (0.5 mol/L), VC (3 mg/ml) or MgCl2 (0.5 mol/L) plus VC (3 mg/ml) at week 2 post-operation, twice weekly, for 2 weeks. Joint pain and pathological changes were assessed by gait analysis, histology, western blotting and micro-CT. Results: Mg2+ and VC showed additive effects to significantly alleviate the joint destruction and pain. The efficacy of this combined therapy could sustain for 3 months after the last injection. We demonstrated that VC enhanced the promotive effect of Mg2+ on HIF-1α expression in cartilage. Additionally, combination of Mg2+ and VC markedly promoted the M2 polarization of macrophages in synovium. Furthermore, combination of Mg2+ and VC inhibited osteophyte formation and expressions of pain-related neuropeptides. Conclusions: Intra-articular administration of Mg2+ and VC additively alleviates joint destruction and pain in OA. Our current formulation may be a cost-effective alternative treatment for OA.

Abstract Background Dye-decolorizing peroxidases (DyPs) represent a novel family of heme peroxidases that use H2O2 as the final electron acceptor to catalyze the oxidation of various organic compounds. A DyP from Irpex lacteus F17 (Il-DyP4, corresponding to GenBank MG209114), obtained by heterologous expression, exhibits a high catalytic efficiency for phenolic compounds and a strong decolorizing ability toward various synthetic dyes. However, the enzyme structure and the catalytic residues involved in substrate oxidation remain poorly understood. Results Here, we obtained a high-resolution structure (2.0 Å, PDB: 7D8M) of Il‑DyP4 with α-helices, anti-parallel β-sheets and one ferric heme cofactor sandwiched between two domains. The crystal structure of Il‑DyP4 revealed two heme access channels leading from the enzyme molecular surface to its heme region, and also showed four conserved amino acid residues forming the pocket for the conversion of hydrogen peroxide into the water molecule. In addition, we found that Trp264 and Trp380, were two important residues with different roles in Il‑DyP4, by using site-directed mutagenesis and an electron paramagnetic resonance (EPR) study. Trp264 is a noncatalytic residue that mainly is used for maintaining the normal spatial conformation of the heme region and the high-spin state of heme Fe3+ of Il‑DyP4, while Trp380 serves as the surface-exposed radical-forming residue that is closely related to the oxidation of substrates including not only bulky dyes, but also simple phenols. Conclusions This study is important for better understanding the catalytic properties of fungal DyPs and their structure–function relationships.

Abstract Background Design modifications in prostheses may cause alterations in gait kinematics, thus influencing functional restoration of knees after total knee arthroplasty (TKA). The aim of the study was to investigate the differences in gait kinematics and clinical outcomes after single radius (SR) versus multiple radius (MR) TKA. Method The present retrospective study included 38 unilateral TKA involving 20 knees using MR design implant and 18 knees using SR design implant. Thirty-six healthy volunteers were also recruited. The mean follow-up time was 16 ± 3 months. At the end of follow-up, the 6 degrees of freedom (DOF) kinematics of knees and range of motion (ROM) were measured with a portable optical tracking system. Knee society score (KSS) and knee injury, and osteoarthritis outcome score (KOOS) were also collected. Results Patients in the SR group had significantly higher scores in activities of daily living (84.7 ± 15.9) and sports and recreation (67.5 ± 25.2) KOOS sub-score than MR group (69.9 ± 17.6, P = 0.012; 50.0 ± 20.8, P = 0.027, respectively). Significant differences were detected between MR knees and SR knees (1.82° ± 3.11° vs 4.93° ± 3.58°, P = 0.009), and MR knees and healthy knees (1.82° ± 3.11° vs 3.62° ± 3.52°, P = 0.032) in adduction/abduction ROM. The proximal/distal translation was significantly smaller in MR knees (0.58 ± 0.54 cm) compared with SR knees (1.03 ± 0.53 cm, P = 0.003) or healthy knees (0.84 ± 0.45 cm, P = 0.039). SR knees (0.24 ± 0.40 cm) had smaller translation compared with the MR group (0.54 ± 0.33 cm, P = 0.017) and control group (0.67 ± 0.36 cm, P = 0.028). No significant difference was detected in the other DOFs during the gait cycle. Significant difference was detected in extension/flexion, internal/external rotation, adduction/abduction, proximal/distal and medial/lateral among MR, SR and healthy knees. Conclusion After TKA, patients have altered gait kinematics compared with the control group. MR and SR design showed varied characteristics in 6 DOF gait kinematics, which could be the cause of the difference in functional outcome.

Background: The prevalence of patellofemoral joint (PFJ) osteoarthritis (OA) after anterior cruciate ligament (ACL) injury was inconsistently reported in the literature. This review summarises the reported prevalence of PFJ OA and risk factors of PFJ OA after ACL injury. Methods: PubMed, Embase, WoS, and MEDLINE (OVID) were searched up to 1 March 2019. A modified version of the Coleman methodology score was used to assess the methodological quality of the included studies. Prevalence of PFJ OA was pooled depended on different interventions in ACL injured populations. Results: Thirty-eight studies were included. Five different radiographic classification methods were used: the Kellgren and Lawrence Grade 2, IKDC Grade B, Fairbank Grade 1, joint space narrowing of Grade 2 based on OARSI, and Ahlbäck Grade 1. One included study used MRI Osteoarthritis Knee Score to evaluate PFJ degenerative changes. The overall prevalence of PFJ OA after ACL injury in included studies varied between 4.5% and 80%. The large variation of PFJ OA prevalence is mainly because of different follow-up period and surgical techniques. The pooled data showed that bone-patellar tendon-bone graft, single-bundle ACL reconstruction (ACLR), and delayed ACLR are likely associated with PFJ degenerative changes after ACL injury. ACLR, delayed ACLR, body mass index (BMI), meniscectomy, patellofemoral chondral lesions, age at surgery, and TFJ OA were identified in the literature inducing PFJ OA after ACL injury. Conclusions: Large variations of PFJ OA after ACL injury are associated with different follow-up period and surgical techniques. ACL reconstructed population with bone-patellar tendon-bone graft, single-bundle reconstruction, and delayed operation time has a high prevalence of PFJ OA. The translational potential of this article: This review focuses more on the effect of surgical technique factors on the degenerative changes on PFJ. The results reveal that BPTB, single-bundle reconstruction, and delayed ACLR are more likely associated with PFJ degenerative changes after ACL injury. These findings imply that awareness of PFJ problems after surgical intervention will remind of surgeons taking PFJ into consideration in operations, which is likely to reduce the incidences of anterior knee pain, patellar maltracking, and over-constrained patella in the early stage after surgery.

Introduction: The avascular necrosis of the femoral head represents the death of bone tissue due to the lack of blood supply. The disease has a progressive evolution; it leads to femoral head collapse and severe arthritis when left untreated. The application of a pedicled bone flap graft is an effective treatment for femoral head necrosis. A pure Mg screw is a kind of degradable screw that can fix the grafted bone flap and prevent long-term stress occlusion and secondary dissection. Case presentation: The report shows the results of the treatment of traumatic femoral head necrosis with a pedicled bone flap with pure Mg screw. A patient had avascular necrosis of the femoral head after 2 years of internal fixation of the femoral neck fracture. We removed the patient's internal fixation hollow nail, cleaned the necrotic bone tissue and took part of the same ipsilateral pedicle iliac bone graft in the femoral head defect with biodegradable pure Mg screw fixation. Within 2 years after the surgery, the patients had no significant progressive necrosis of the femoral head. Postoperative Harris scores showed that the patient's left hip function was significantly improved compared with his preoperative state. The pure Mg screw in the body had gradually degraded. After 2 years, the screw's diameter had been significantly reduced compared with 3 days after the surgery. The postoperative Harris score showed that the patient's left hip function was significantly improved compared with the second preoperative examination. Discussion: The discussion includes the reasons for the choices of surgical approaches, the mode of pure Mg screw degradation and the postoperative functional assessment of the patient's left hip. Conclusion: Pure Mg screw fixation pedicled bone flap transplantation is an effective surgical treatment for femoral head necrosis in young patients. Pure Mg screw is a biodegradable internal fixation device with good biocompatibility, which has a good clinical application prospects. The translational potential of this article: Degradable pure Mg screw has the potential to preserve hip joint therapy for the treatment of femoral head necrosis.

ObjectivesRheumatoid arthritis (RA) is a disabling disease with a high incidence that is regularly accompanied by cardiovascular complications. Several studies have suggested that renin–angiotensin–aldosterone system (RAAS) is closely associated with RA. The aim of this study was to investigate the mechanisms underlying Angiotensin-(1–7) [Ang-(1–7)] and its Mas receptor agonist (AVE0991) on joint inflammation and cardiac complications in a collagen-induced arthritis (CIA) model.MethodsCollagen type II was injected into DBA/1 mice to construct an arthritis model. CIA mice were treated with Ang-(1–7) (2.0 mg/kg intraperitoneally) and AVE0991 (3.0 mg/kg intraperitoneally). The serum levels of inflammatory cytokines [tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1 β, IL-6, and C-reactive protein (CRP)] were determined by ELISA. The mitogen-activated protein kinase (MAPK) and nuclear factor-kappaB (NF-κB) signaling pathways in joint tissues and the transforming growth factor (TGF)-β/Smad pathway and levels of α-Smooth muscle action (SMA) and β-myosin heavy chain (MHC) protein expression in cardiac tissues were assessed by western blots. The levels of TGF-β/Smad pathway, α-SMA, and β-MHC RNA in cardiac tissues were analyzed by real time-PCR. The levels of receptor activator of nuclear factor kappa ligand (RANKL) and promoting matrix metalloproteinase (MMP)-3 expression in the ankle joints were detected by immunohistochemistry and real time-PCR.ResultsAng-(1–7) and AVE0991 reduced the levels of inflammatory cytokines and inhibited the MAPKs and NF-κB signaling pathways in ankle joint tissues, reduced RANKL and MMP3 expression, and ameliorated local joint inflammation and bone destruction compared with the control group. In addition, Ang-(1–7) and AVE0991 attenuated the TGF-β/Smad signaling pathway, reduced the levels of α-SMA and β-MHC expression, and diminished inflammatory cell infiltration into the myocardial interstitium and myocardial interstitial fibrosis in the hearts of CIA mice.ConclusionsAng-(1–7) alleviated joint damage caused by inflammation likely through the attenuation of NF-κB and MAPK pathways and ameliorated inflammation-induced cardiac fibrosis and activation of the TGF-β/Smad pathway. Moreover, Ang-(1–7) was likely mediated through the Mas receptor. This study provides theoretical evidence for exploring novel clinical therapeutic approaches for RA and its cardiac complications.

In kidney disease, inflammation and lipid dysmetabolism are often associated together, however, the effect and mechanism of inflammatory mediators and lipid dysmetabolism on kidney damage is still unclear. In this study, Wistar rats were randomized into four groups: normal diet + saline (Group N), high-fat diet (HF)+ saline (Group HF), normal diet + adriamycin (Group ADR), HF + adriamycin (Group ADR + HF). After 10 weeks of feeding, rats in each group were randomly sacrificed. We found that the protein content of urine in ADR and ADR + HF groups were significantly higher than that of group N and HF while the serum levels of total protein and albumin in the ADR and ADR + HF groups decreased correspondingly. The serum levels of triglyceride, total cholesterol and low-density lipoprotein in the HF, ADR and ADR + HF groups increased. In the treatment groups, mesangial proliferation, matrix accumulation, tubular vacuolization, inflammatory cell infiltration and fat deposition were detected. These pathological changes were the most serious in the ADR + HF group. The expression of tumor necrosis factor-α (TNF-α) and transforming growth factor-β1 (TGF-β1) were increased in each treatment group, especially in the ADR + HF group. Our results suggested that the inflammatory factors and abnormal lipid levels can activate the inflammatory response in kidney of the Wistar rats, and lead to a series of pathological changes in renal tissue, and inflammatory factors and lipid dysmetabolism can aggravate damage in the kidney.

Abstract Knee osteoarthritis (KOA) is reported to have characteristic kinematics during walking. However, the relationship between Kellgren-Lawrence (K/L) score and the 3D kinematic gait of patients with medial KOA remains unclear. Here, ninety-seven patients with medial KOA and thirty-eight asymptomatic participants were involved. Patients with medial KOA were divided into early, moderate, and severe KOA based on the K/L score. Through kinematic gait analysis, we found a relationship between K/L score and 3D kinematic gait for patients. All KOA knees had a significantly reduced range of motion. As the K/L score was increasing, the knee flexion at the heel strike and 50% of the stance phase increased while the peak knee flexion in the swing phase decreased. In addition, the adduction and femoral rotation increased internally at the heel strike, 50% of the stance phase, and maximum angle of the swing phase. Femoral translation increased anteriorly and distally at the heel strike and 50% of the stance phase. The severe group had more medial translation than the asymptomatic groups. Significant alterations of three-dimensional joint kinematics were identified in subjects suffering various severities in Chinese patients. This study provides an important reference for the treatment options, therapy assessment, and rehabilitation of KOA.

Abstract Background Data about minimally invasive surgery for the treatment of patients with degenerative disc disease (DDD) has been reported. However, no quantitative knowledge about the biomechanical characteristics of the spinous processes in patients with DDD after operation was reported in the literature. Methods Fourteen adult patients with DDD at the L3-4 level were recruited and scanned using computed tomography (CT) to construct three-dimensional (3D) anatomical vertebral models of L2-5. These patients were asked to maintain four positions to acquire 6DOF data about the area of the spine being investigated (L2-5). Fluoroscopy was used to capture spinal motion. 6DOF data from the fluoroscopic images of the four positions was compared to evaluate the kinematics before operation and 6 months after direct lateral interbody fixation (DLIF). Results Altered kinematics were found mainly in rotation. For the images captured while patients were in the supine position, no significant differences were detected in different functional positions before and after operation. At other positions, the most kinematic involved level was the L3-4 level, which was followed by the L4-5 level. The range of flexion-extension motion at all levels decreased after operation (by an average of 1° to 7°) while different trends were found in left-right bending/rotation. Overall, after surgical treatment, functional activities were partially restored. Conclusions Overall the lumbar spinous processes (LSP) at each level responded differently, regarding rotation, before and after DLIF. This data provides new insights for the evaluation of function before and after surgical treatment in patients with LSP disease.

Muscle-controlled changes in surface structures are employed in nature to achieve rapid, reversible changes in colour and transparency. Here the authors develop a simple, bilayer platform capable of several distinct analogous mechanochromic behaviours.

The angiotensin converting enzyme 2-angiotensin-(1-7)-Mas axis (ACE2-Ang-(1-7)-Mas axis) is reported to participate in lipid metabolism in kidney, but its precise effects and underlying mechanisms remain unknown. We hypothesized that Ang-(1-7) reduces lipid accumulation and improves renal injury through the low density lipoprotein receptor-sterol regulatory element binding proteins 2-SREBP cleavage activating protein (LDLr-SREBP2-SCAP) system by suppressing inflammation in high fat diet (HFD)-fed mice. In this study, male C57BL/6 mice were randomized into four groups: STD (standard diet)+saline, HFD+saline, HFD+Ang-(1-7) and STD+Ang-(1-7). After 10 weeks of feeding, mice were administered Ang-(1-7) or saline for two weeks. We found that high inflammation status induced by HFD disrupted the LDLr-SREBP2-SCAP feedback system. Treatment of mice fed a high-fat diet with Ang-(1-7) induced significant improvement in inflammatory status, following the downregulation of LDLr, SREBP2 and SCAP, and then, decreased lipid deposition in kidney and improved renal injury. In conclusion, the anti-inflammatory effect of Ang-(1-7) alleviates renal injury triggered by lipid metabolic disorders through a LDLr- SREBP2-SCAP pathway.