Metrnl deficiency retards skin wound healing in mice by inhibiting AKT/eNOS signaling and angiogenesis.

Meteorin-like (Metrnl) is a novel secreted protein with various biological activities. In this study, we investigated whether and how Metrnl regulated skin wound healing in mice. Global Metrnl gene knockout mice (Metrnl-/-) and endothelial cell-specific Metrnl gene knockout mice (EC-Metrnl-/-) were generated. Eight-mm-diameter full-thickness excisional wound was made on the dorsum of each mouse. The skin wounds were photographed and analyzed. In C57BL/6 mice, we observed that Metrnl expression levels were markedly increased in skin wound tissues. We found that both global and endothelial cell-specific Metrnl gene knockout significantly retarded mouse skin wound healing, and endothelial Metrnl was the key factor affecting wound healing and angiogenesis. The proliferation, migration and tube formation ability of primary human umbilical vein endothelial cells (HUVECs) were inhibited by Metrnl knockdown, but significantly promoted by addition of recombinant Metrnl (10 ng/mL). Metrnl knockdown abolished the proliferation of endothelial cells stimulated by recombinant VEGFA (10 ng/mL) but not by recombinant bFGF (10 ng/mL). We further revealed that Metrnl deficiency impaired VEGFA downstream AKT/eNOS activation in vitro and in vivo. The damaged angiogenetic activity in Metrnl knockdown HUVECs was partly rescued by addition of AKT activator SC79 (10 µM). In conclusion, Metrnl deficiency retards skin wound healing in mice, which is related to impaired endothelial Metrnl-mediated angiogenesis. Metrnl deficiency impairs angiogenesis by inhibiting AKT/eNOS signaling pathway.

Intramedullary nailing versus plating fixation for the treatment of midshaft clavicular fractures: A meta-analysis of randomized controlled trials.

PURPOSE: This study was to test the hypothesis that intramedullary (IM) nailing fixation of midshaft clavicle fractures could result in better clinical outcomes and lower complications rates than plating fixation. METHODS: PubMed, Embase, and the Cochrane Library database were used to search all English language published randomized controlled trials (RCTs) of midshaft clavicle fractures using plating versus IM nailing. The characteristics of the study participants were collected. Outcomes of postoperative shoulder functional measurements, operative data and complications rates were meta-analyzed. RESULTS: Eight hundred and ninety-five patients in ten RCTs and three quasi-RCTs were involved in the meta-analysis. The results of meta-analysis of these studies showed that the functional outcome evaluated by the Constant Shoulder and Disabilities of the Arm, Shoulder and Hand (DASH) scores after accepting IM nailing was significantly better than that of plating fixation at one year post-operatively (P < 0.01), with the heterogeneity of 43% and 91%, respectively. Sensitivity analyses of the pooled results of Constant and DASH scores displayed that the functional advantage of IM nailing fixation comes from the subgroup of locked IM nailing. Further, regarding the operative statistics, operative time, blood loss and wound length were significantly less in the IM nailing group than the plating group (P < 0.001). The rates of infection, major complications and complications-related revision surgery were significantly higher in the plating group than the IM nailing group; however, there were no significantly statistical differences in other complications, e.g., nonunion, refracture after hardware removal, implant failure, symptomatic hardware, etc. (P > 0.05). CONCLUSION: The observations in this review suggested that IM nailing, especially locked IM nailing, could provide better shoulder functional outcome at one-year follow-up. Moreover, IM nailing fixation could effectively reduce operative time, blood loss, rates of infection, major complications, and revision surgery than plating. Further high-quality clinical trials with large samples and consistent designs are still needed to verify the long-term functional advantage of locked and unlocked IM nailing for midshaft clavicle fractures. LEVEL OF EVIDENCE: Level II.

Effects of less invasive surfactant administration versus intubation-surfactant-extubation on bronchopulmonary dysplasia in preterm infants with respiratory distress syndrome: a single-center, retrospective study from China.

BACKGROUND: This study evaluated the effects of less invasive surfactant administration (LISA) and intubation-surfactant-extubation (InSurE) on bronchopulmonary dysplasia (BPD) in preterm infants with respiratory distress syndrome (RDS). METHODS: Neonates with respiratory distress syndrome requiring surfactant, with gestational age < 32 weeks and birth weight < 1500 g admitted to our neonatal intensive care unit from January 2018 to December 2019, were retrospectively analyzed. LISA and InSurE were used independently. The incidence of BPD at 36 weeks postmenstrual age, pre-discharge mortality, and need for mechanical ventilation (MV) within 72 h of birth were compared between LISA and InSurE group. Secondary outcomes including necrotizing enterocolitis requiring surgery, retinopathy of prematurity ≥ stage 3, patent ductus arteriosus requiring medical therapy or surgery, and length of hospitalization were analyzed. RESULTS: Among the 148 included neonates, there were 46 and 102 infants in LISA group and InSurE group, respectively. There were no significant differences in BPD incidence, the severity of BPD at 36 weeks postmenstrual age, and the rate of MV within the first 72 h after birth between the two groups (P > 0.05, respectively). The incidences of necrotizing enterocolitis requiring surgery, retinopathy of prematurity ≥ stage 3, patent ductus arteriosus requiring medical therapy or surgery, and length of hospitalization did not differ significantly between the two groups (P > 0.05, respectively). CONCLUSIONS: For surfactant administration among preterm infants with respiratory distress syndrome, LISA did not decrease bronchopulmonary dysplasia and severity of BPD at 36 weeks postmenstrual age. The benefits of LISA would require further evaluations.

The oblique triangle configuration of three parallel screws for femoral neck fracture fixation using computer-aided design modules.

Closed reduction and internal fixation with three cannulated compression screws is a common method for treating femoral neck fractures in young and middle-aged patients. Protocols including the inverted triangle configuration and dispersion of the screws still needed further supports. The purpose of this study was to explore a novel oblique triangle configuration (OTC) of three screws in fixing femoral neck fractures based on the morphology of the femoral neck isthmus (FNI). The computer-aided design modules were used to explore the ideal spatial configuration with largest triangle by three parallel screws. A univariate evaluation model was established based on the oval-like cross-section of the FNI. When the three screws were positioned by the OTC, Inverted Equilateral Triangle Configuration (IETC), and the Maximum Area Inverted Isosceles Triangle Configuration (MA-IITC) respectively, the proportion of area and circumference in the cross-section of FNI and the changing trend of proportion were compared under various torsion angles, eccentricity, and cross-sectional area of FNI. The area and circumference ratios of the parallel screws using the OTC method were significantly higher than in the IETC and MA-IITC groups. In the univariate evaluation model, the OTC area ratio and circumference ratio remained stable under the different femoral neck torsion angles, FNI cross-sectional area, and eccentricity. The OTC method provided an ideal spatial configuration for the FNA fixation with the largest area using three parallel screws. The position of the posterior screw was also away from the metaphyseal artery, potentially reducing the possibility of vascular injury and screw penetrating.

Comparison of oblique triangular configuration and inverted equilateral triangular configuration of three cannulated screws in treating unstable femoral neck fracture: A finite element analysis.

BACKGROUND: The cross-sectional area of three parallel screws might affect the stability of the internal fixation of femoral neck fractures. The screws fixed in the oblique-triangle configuration (OTC) were assumed to have a larger cross-sectional area, but the biomechanical stability has not yet been validated. In this study, finite element analyses were performed to compare the biomechanical properties of the internal fixation fixed by the OTC and the traditional Inverted Equilateral Triangle Configuration (IETC). METHOD: Pauwels type III fracture was established on the three-dimensional femoral model and three cannulated screws with the OTC and traditional IETC methods were applied. The oblique-triangle configuration with the largest area inscribed the femoral neck isthmus by the three screws was determined, the area and circumference of the cross-section formed by the OTC and IETC model were compared. Stress, strain, and displacement peaks of the two configuration models under different loads were compared. Twelve pairs of nodes on the fracture ends were selected and the displacement of the fracture ends was evaluated through the displacement between these nodes. RESULTS: The area and circumference of the cross-section formed by the OTC were larger than those in the IETC model. The degree of stress dispersion around the screw holes in the OTC model was better than that of the IETC, but the stress distribution order of the three screws in the two models was consistent. The maximum stress, strain, displacement, and displacement of the fracture end in the OTC model were smaller than those in the IETC model. The stress, strain, displacement, and fracture end displacement peaks of the two fixed models gradually increase with the increase of loads. CONCLUSION: The oblique-triangle configuration showed superior mechanical properties than the IETC in finite element analyses. This study suggests that when three screws are fixed in parallel method, the larger the cross-sectional area of the screw configuration, the better stability of the internal fixation might be obtained. Furthermore, the biomechanical properties of various spatial configurations and screw holes of the three parallel screws need to be considered before clinical practice.

The Oval-like Cross-section of Femoral Neck Isthmus in Three-dimensional Morphological Analysis.

OBJECTIVES: To investigate the cross-section shape of the femoral neck isthmus (FNI) in three-dimensional reconstruction model of the femoral neck. METHODS: From December 2009 to December 2012, computed tomography (CT) data of bilateral hip joint from 200 consecutive patients (137 males and 63 females, 69.41 ± 9.21 years old, ranged from 50-85 years old) who underwent surgical treatments for proximal femoral fracture were retrospectively reviewed. The 3D model of the proximal femur was reconstructed, and the "inertia axis" method, which was applied to measure the long and short axes of the cross-section of the FNI, was established. The cross-sectional area and perimeter were calculated by a formula using the length of the long and short axes and then compared with the actual measured values by the software. Correlation between the descriptive parameters of the FNI cross-section (area, perimeter, and eccentricity) and patients' demographics (age, height, and weight) was analyzed. Stepwise linear regression analysis was used to determine the main relevant factors. RESULTS: The ICC results showed excellent data reproducibility ranged from 0.989 to 0.996. There was no significant difference in the cross-sectional area of the FNI between the actual measured values and the predicted values using the formula (732.83 ± 126.74 mm2 vs 731.62 ± 128.15 mm2 , P = 0.322). The perimeter using the two methods showed narrow while significant difference (97.86 ± 8.60 mm vs 92.84 ± 8.65 mm, P < 0.001), the actual measured values were about 5 mm greater than the predicted values. The parameters (area, perimeter, and eccentricity) were significantly larger in male than female (P < 0.001). A positive correlation between the cross-sectional area, perimeter, height, and weight was observed. The stepwise linear regression analysis showed that the regression equation of the FNI area was as follows: Y = -1083.75 + 1033.86 × HEIGHT + 1.92 × WEIGHT, R2 = 0.489. CONCLUSION: The cross-section shape of the FNI appears to be oval-like in the 3D model, which is separated according to the inertia axis, and the findings proposed an anatomical basis for the further study of the spatial configuration of cannulated screws in the treatment of femoral neck fractures.

A Hybrid Uniplanar Pedicle Screw System with a New Intermediate Screw for Minimally Invasive Spinal Fixation: A Finite Element Analysis.

PURPOSE: A hybrid pedicle screw system for minimally invasive spinal fixation was developed based on the uniplanar pedicle screw construct and a new intermediate screw. Its biomechanical performance was evaluated using finite element (FE) analysis. METHODS: A T12-L2 FE model was established to simulate the L1 vertebral compression fracture with Magerl classification A1.2. Six fixation models were developed to simulate the posterior pedicle screw fracture fixation, which were divided into two subgroups with different construct configurations: (1) six-monoaxial/uniplanar/polyaxial pedicle screw constructs and (2) four-monoaxial/uniplanar/polyaxial pedicle screw constructs with the new intermediate screw. After model validation, flexion, extension, lateral bending, and axial rotation with 7.5 Nm moments and preloading of 500 N vertical compression were applied to the FE models to compare the biomechanical performances of the six fixation models with maximum von Mises stress, range of motion, and maximum displacement of the vertebra. RESULTS: Under four loading scenarios, the maximum von Mises stresses were found to be at the roots of the upper or lower pedicle screws. In the cases of flexion, lateral bending, and axial rotation, the maximum von Mises stress of the uniplanar screw construct lay in between the monoaxial and polyaxial screw constructs in each subgroup. Considering lateral bending, the uniplanar screw construct enabled to lower the maximum von Mises stress than monoaxial and polyaxial pedicle screw constructs in each subgroup. Two subgroups showed comparable results of the maximum von Mises stress on the endplates, range of motion of T12-L1, and maximum displacement of T12 between the corresponding constructs with the new intermediate screw or not. CONCLUSIONS: The observations shown in this study verified that the hybrid uniplanar pedicle screw system exhibited comparable biomechanical performance as compared with other posterior short-segment constructs. The potential advantage of this new fixation system may provide researchers and clinical practitioners an alternative for minimally invasive spinal fixation with vertebral augmentation.

Incidence and clinical significance of abnormalities in potassium, sodium and calcium levels in elderly patients with hip fractures during the perioperative period.

OBJECTIVE: This study aims to investigate the incidence and clinical significance of sodium, potassium and calcium electrolyte disturbances in elderly patients with hip fracture before an operation. METHODS: The clinical data of 220 patients with intertrochanteric fracture and 261 patients with femoral neck fracture from September 2013 to December 2016 in our hospital (≥60 years old) was reviewed. The sodium, potassium and calcium values, and the underlying diseases of patients were recorded after the first blood test. These patients were divided into two groups according to the fracture site: femoral neck fracture group and intertrochanteric fracture group. Then, the differences between these two groups were compared to analyze the proportion of electrolyte disturbances in elderly patients with hip fracture, and explore its clinical significance. RESULTS: Patients with intertrochanteric fractures were older than patients with femoral neck fracture. There was no significant difference in the prevalence of underlying diseases between these two groups. The incidence of hyponatremia, hypokalemia and hypocalcemia was 10.0%, 32.9% and 1.4%, respectively, in the femoral neck fracture group, and 24.3%, 21.1% and 7.7%, respectively, in the intertrochanteric fracture group. The incidence of hypernatremia, hyperkalemia and hypercalcemia was 1.4%, 1.4% and 0.9%, respectively, in the femoral neck fracture group, and 1.1%, 0.7% and 0.8%, respectively, in the intertrochanteric fracture group. CONCLUSION: Patients with old hip fractures before an operation are prone to hyponatremia, hypokalemia and hypocalcemia, and most of them have mild electrolyte disorders, which needs to be corrected in time. Furthermore, some patients urgently need urgent supplementation ofblood electrolytes for some diseases, the correction of electrolyte disorders, and the prevention of serious adverse consequences. KEY WORDS: Femoral neck fracture, Femoral intertrochanteric fracture, Hyponatremia, Hypokalemia, Hypocalcemia.

Erratum to radiographic assessment of the cup orientation after total hip arthroplasty: a literature review.

[This corrects the article DOI: 10.21037/atm.2019.12.150.].

Three-dimensional morphological analysis of the femoral neck torsion angle-an anatomical study.

BACKGROUND: The femoral neck torsion angle (FNTA) is an important but often neglected parameter in assessments of the anatomical morphology of the femoral neck, which is often confused with the femoral neck anteversion angle (FNAA) in the current literature. Currently, the measurement methods reported in the literature all adopt the naked eye or two-dimensional (2D) visualization method, and the measurement parameters and details are not clearly defined. The objection of this research was to provide a reliable 3D method for determining the femoral neck axis, to improve the measurement method of the FNTA, and to analyze the anatomical and clinical significance of the results. METHODS: Computed tomography (CT) data of 200 patients who received a lower extremity CT angiography examination were selected, and the bilateral femurs were reconstructed with three dimensional CT (3D CT). First, the 3D axis of the femoral neck was built. Second, the long axis of the cross section the femoral neck isthmus (FNI) and femoral neck basilar part (FNB) were confirmed by the "inertia axes" method, and the plane consisting of the long axis of the cross-section and the center of the femoral head was defined as the long axial plane. Third, the coronal plane of the proximal femur was determined through the long axis of the proximal femur and the femoral coronal. Finally, the FNTAs (the angles between the long axial planes and the coronal plane of the proximal femur) of FNI and FNB were measured. The size of FNTA was compared between the sexes and sides and different locations, the correlation between the parameters and age, height, and weight were evaluated. RESULTS: The difference in FNTA was statistically significant between the isthmus and the basilar part (isthmus 30.58 ± 8.90° vs. basilar part 23.79 ± 3.98°; p < 0.01). Significant difference in the FNTA was observed between the sexes (males 31.99 ± 9.25° vs. females 27.49 ± 7.19°; p < 0.01). The increase in FNTA from the basilar part to the isthmus was 6.79 ± 8.06°, and the male (7.87 ± 8.57°) was greater than the female (4.44 ± 6.23°, p < 0.01). However, no significant difference in the values was observed between sides. Height exerted the greatest effect on the FNTA according to the correlation analysis (r = 0.255, p< 0.001). CONCLUSIONS: This study found a reliable 3D method for the determination of the femoral neck axis improved the measurement method of the FTNTA and made it more accurate and repeatable. The results provided a methodological basis and theoretical support for the research and development of internal fixation device for femoral neck fracture and the spatial configuration of implants in treatment. And the optimal opening point of the femoral medullary cavity was recommended to locate at the posterior position of the top of the femoral neck cross-section during hip replacement.

Radiographic assessment of the cup orientation after total hip arthroplasty: a literature review.

Optimal acetabular cup orientation is of substantial importance to good long-term function and low complication rates after total hip arthroplasty (THA). The radiographic anteversion (RA) and inclination (RI) angles of the cup are typically studied due to the practicability, simplicity, and ease of interpretation of their measurements. A great number of methods have been developed to date, most of which have been performed on pelvic or hip anteroposterior radiographs. However, there are primarily two influencing factors for these methods: X-ray offset and pelvic rotation. In addition, there are three types of pelvic rotations about the transverse, longitudinal, and anteroposterior axes of the body. Their effects on the RA and RI angles of the cup are interactively correlated with the position and true orientation of the cup. To date, various fitted or analytical models have been established to disclose the correlations between the X-ray offset and pelvic rotation and the RA and RI angles of the cup. Most of these models do not incorporate all the potential influencing parameters. Advanced methods for performing X-ray offset and pelvic rotation corrections are mainly performed on a single pelvic AP radiograph, two synchronized radiographs, or a two-dimensional/three-dimensional (2D-3D) registration system. Some measurement systems, originally developed for evaluating implant migration or wear, could also be used for correcting the X-ray offset and pelvic rotation simultaneously, but some drawbacks still exist with these systems. Above all, the 2D-3D registration technique might be an alternative and powerful tool for accurately measuring cup orientation. In addition to the current methods used for postoperative assessment, navigation systems and augmented reality are also used for the preoperative planning and intraoperative guidance of cup placement. With the continuing development of artificial intelligence and machine learning, these techniques could be incorporated into robot-assisted orthopaedic surgery in the future.

Evolution and Current Applications of Robot-Assisted Fracture Reduction: A Comprehensive Review.

Robots in orthopedic surgery have been developed rapidly for decades and bring significant benefits to the patients and healthcare providers. However, robotics in fracture reduction remains at the infant stage. As essential components of the current robotic system, external fixators were used in fracture reduction, including the unilateral and Ilizarov-like ring fixators. With emerging of the industrial robots and mechanical arms, their sterilized variants were developed as the serial robots, including the traction device and robotic arm, for fracture reduction. Besides, parallel robots (e.g., Gough-Stewart platform) were devised for lower extremity traction and fracture reduction. After combining the advantages of the serial and parallel mechanisms, hybrid robots can fulfill specific clinical requirements (e.g., the joint fracture, including multiple major fragments). Furthermore, with the aid of intra-operative navigation systems, fracture reduction can be performed under real-time guidance. The paper presents a comprehensive overview of the advancement of the robots in fracture reduction and evaluates research challenges and future perspectives, including ergonomic and economic issues, operation time, artificial realities and intelligence, and telesurgery.

The synergetic effect of pelvic rotation and X-ray offset on radiographic angles of the acetabular cup.

The objective of this study is to investigate the synergetic effect of the pelvic rotation and X-ray offset on the radiographic anteversion/inclination (RA/RI) angles of the acetabular cup using a mathematical model. A cone model for establishing the spatial relationship between a three-dimensional (3D) circle and its two-dimensional (2D) elliptical projection is utilized to quantify the relationship between the 3D RA/RI angles of the cup and their 2D counterparts with different types of pelvic rotations in pelvic/hip anteroposterior radiographs. The results reveal that the effect of inlet/outlet views on the 2D RA angle is similar to that of iliac/obturator views. The permissible ranges of pelvic rotation for the 2D RA angle with an acceptable bias are the 3D space formed by the limits of triple axial rotations. For a specified acceptable bias of the 2D RA angle, these ranges are almost equal between pelvic and hip radiographs. The combined inlet/obturator or outlet/iliac views can maintain the 2D RA angle of a pelvic radiograph within the same range of acceptable bias as that of a hip radiograph. For a 2D RA angle with an acceptable bias, the permissible range of pelvic rotation needs to be evaluated with equal attention in both radiographs. Graphical abstract The traditional methods for calculating the radiographic angles of the acetabular cup are based on the ellipse projection of the opening circle of the cup on radiographs. However, with varying locations of the X-ray source and pelvis rotations about different axes, the outline of this ellipse projection will change, and accordingly, the traditional method and calculating results will be inaccurate. In this study, a cone model for three-dimensional circle-to-two-dimensional ellipse projection is utilized to incorporate the effect of X-ray offset and quantify the relationships of the radiographic angles of the cup with the true orientation of the cup and pelvic rotations in either pelvic or hip anteroposterior radiographic situation.

Isoflurane produces antidepressant effects inducing BDNF-TrkB signaling in CUMS mice.

RATIONALE: The volatile anesthetic isoflurane is suggested to produce a rapid and robust antidepressive effect in preliminary clinical trials. Recently, isoflurane was found to activate the tropomyosin receptor kinase B (TrkB) signaling which is the underlying mechanism of the rapid antidepressant ketamine. OBJECTIVE: Our study investigated the effect of isoflurane anesthesia on chronic unpredictable mild stressed (CUMS) model in mice and verified the role of brain-derived neurotrophic factor (BDNF)/TrkB/ the mammalian target of rapamycin (mTOR) signaling in the antidepressant effect of isoflurane. METHODS: We employed the CUMS model of depression to assess the rapid antidepressant effect of isoflurane by the forced swimming test (FST), the sucrose preference test (SPT), and the novelty suppressed feeding test (NSFT). The protein expression of BDNF and TrkB/protein kinase B (PKB or Akt)/mTOR was determined through Western blot. The dendritic spine density in the hippocampus and medial prefrontal cortex (PFC) was measured by the Golgi staining. RESULTS: A brief burst-suppressing isoflurane anesthesia rapidly reversed the behavioral deficits caused by CUMS procedure, normalized the expression of BDNF and further activated the TrkB signaling pathway in CUMS-induced stressed mice in both prefrontal cortex (PFC) and hippocampus (HC). All of those behavioral and proteomic effects were blocked by K252a, a selective receptor inhibitor of TrkB. Isoflurane significantly promoted the formation of dendritic spines in both medial prefrontal cortex (mPFC), CA1, CA3, and DG of the hippocampus. CONCLUSION: Our study indicates that isoflurane exerts a rapid antidepressant-like effect in CUMS depression animal model, and the activation of BDNF/TrkB signaling pathway plays an indispensable role in the biological and behavioral antidepressant effects of isoflurane. A single exposure to isoflurane could repair synaptic damage caused by chronic stimulation.

Early Experience with Reduction of Unstable Pelvic Fracture Using a Computer-Aided Reduction Frame.

PURPOSE: The optimal closed reduction technique for unstable pelvic fractures remains controversial. The purpose of this study is to verify the effectiveness and report early experiences with the reduction of unstable pelvic fractures using a computer-aided pelvic reduction frame. METHODS: From January 2015 to August 2016, a total of 10 patients with unilateral unstable pelvic fractures were included in this study. The surgical reduction procedure was based on the protocol of the computer-aided pelvic reduction frame that we proposed in a previous work. The quality of the reductions achieved using this system was evaluated with residual translational and rotational differences between the actual and virtual reduction positions of pelvis. The duration of the operation was recorded for quality control. RESULTS: The mean times required to set up the frame, to complete the virtual surgery simulation, and to reduce the unstable pelvic fractures were 10.3, 20.9, and 7.5 min, respectively. The maximum residual translational and rotational displacements were less than 6.5 mm and 3.71 degrees, respectively. CONCLUSIONS: This computer-aided reduction frame can be a useful tool for the speedy and accurate reduction of unstable pelvic fractures. Further clinical studies should be conducted with larger patient samples to verify its safety and efficacy.

Three-dimensional orientation and location-dependent varying rules of radiographic angles of the acetabular cup.

AIM: The aim of this study is to demonstrate the varying rules of radiographic angles following varying three-dimensional (3D) orientations and locations of cup using an accurate mathematical model. METHODS: A cone model is established to address the quantitative relationship between the opening circle of cup and its ellipse projection on radiograph. The varying rules of two-dimensional (2D) radiographic anteversion (RA) and inclination (RI) angles can be analyzed. RESULTS: When the centre of cup is located above X-ray source, with proper 3D RI/RA angles, 2D RA angle can be equal to its 3D counterpart, and 2D RI angle is usually greater than its 3D counterpart. Except for the original point on hip-centered anterior-posterior radiograph, there is no area on radiograph where both 2D RA and RI angles are equal to their 3D counterparts simultaneously. DISCUSSION: This study proposes an innovative model for accurately explaining how 2D RA/RI angles of cup are varying following different 3D RA/RI angles and location of cup. The analysis results provide clinicians an intuitive grasp of knowledge about 2D RA/RI angles greater or smaller than their 3D counterparts post-operatively. The established model may allow determining the effects of pelvic rotations on 2D radiographic angles of cup.

Anti-Inflammatory Effects of TRAF-Interacting Protein in Rheumatoid Arthritis Fibroblast-Like Synoviocytes.

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease characterized by inflammatory cell infiltration, synovial inflammation, and cartilage destruction. Proliferative fibroblast-like synoviocytes (FLS) play crucial roles in both propagation of inflammation and joint damage because of their production of great amount of proinflammatory cytokines and proteolytic enzymes. In this study, we investigate the role of TRAF-interacting protein (TRIP) in regulating inflammatory process in RA-FLS. TRIP expression was attenuated in RA-FLS compared with osteoarthritis- (OA-) FLS. Overexpression of TRIP significantly inhibited the activation of NF-κB signaling and decreased the production of proinflammatory cytokines and matrix metalloproteinases (MMPs) in TNFα-stimulated RA-FLS. Furthermore, TRIP was found to interact with transforming growth factor ß-activated kinase 1 (TAK1) and promoting K48-linked polyubiquitination of TAK1 in RA-FLS. Our results demonstrate that TRIP has anti-inflammatory effects on RA-FLS and suggest TRIP as a potential therapeutic target for human RA.