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Introduction: Galectin-1 (Gal-1), a carbohydrate-binding protein, is differentially expressed by various normal and pathological tissues and appears to be functionally polyvalent. Recent evidence indicates that Gal-1 is involved in the proliferation of adult neural progenitor cells in neurogenic regions during adulthood. However, localization and functional roles of Gal-1 in the adult spinal cord have not been clarified. Method: Here, we investigated the spatio-temporal profile of endogenous Gal-1 expression by in situ hybridization before and after experimental adult spinal cord injury and examined the correlation of Gal-1 with the fate of dividing cells in vivo, using double-labeling methods. Gal-1 mRNA was detectable at a relatively low level in uninjured spinal cord, but was markedly increased in the gray matter and/or white matter and in the ependyma rostral and caudal to the lesion site after injury. Results: Co-localization results revealed that Gal-1 was expressed predominantly by GFAP-positive reactive astrocytes. In addition, intrathecal infusion of recombinant Gal-1 enhanced cell division and reactive astrocytosis in the adult spinal cord. To explore further whether Gal-1 and reactive astrocytes provide a synergistic effect on neurological recovery following SCI, we investigated the differences in behavioral analysis between wild-type (WT) and reactive astrocyte-deficient transgenic mice after injury and found neuroprotective effects of Gal-1 appeared to be specifically mediated through reactive astrocytes. Conclusion: These results indicate that Gal-1 exhibits great potential as a novel neuroprotective agent for the treatment of SCI. [ABSTRACT FROM AUTHOR]

Introduction: The purpose of this study was to describe our transverse patella double tunnel technique to reconstruct the medial patellofemoral ligament (MPFL) with a hamstring tendon autograft in patients who suffered recurrent dislocation of the patella, and to evaluate the intermediate-term outcomes of reconstruction treatment. Materials and methods: Fifty-nine consecutive knees (52 patients) with recurrent dislocation of the patella without marked predisposing anatomic abnormalities and radiographically documented moderate/severe osteochondral lesions were included in the study. Outcomes were assessed with physical and radiographic examination, the Kujala and the modified Cincinnati scores preoperatively and postoperatively at 3, 6, 12, 36, 60 and 84 months. Results: There were 19 male and 33 female patients with up to 7.1-year follow-up (mean 5.7 years). The mean age was 24.3 years. A comparison of preoperative scores with those obtained at most recent follow-up revealed a significant improvement for all outcomes measured: range of motion (30 ± 2° vs. 125 ± 5°, P < 0.01), the mean Kujala scores (41.4 vs. 82.6, P < 0.001), the mean modified Cincinnati scores (50.6 vs. 88.7, P < 0.01), the mean congruence angle (12.2° vs. −2.4°, P < 0.01) and the mean tilt angle (11.4° vs. 8.4°, P < 0.05). No recurrent episodes of dislocation or subluxation were postoperatively reported, although there were seven knees with an occasional unstable feeling without redislocation. Conclusions: MPFL reconstruction with the double-transverse tunnels technique is safe and effective in patients of all ages, without marked predisposing anatomic abnormalities and moderate/severe osteochondral lesions, who suffered recurrent dislocation of the patella. [ABSTRACT FROM AUTHOR]

Due to atypical clinical presentation, wide use of antibiotics and lack of specificity in diagnosis, misdiagnosis is common, and diagnosis of tubercular infection in a joint is increasingly difficult. The use of arthroscopy for the diagnosis and treatment of early-stage knee TB has rarely been reported. Through this case series we describe the usefulness of arthroscopy for the management of synovial tuberculosis of the knee joint. Synovectomy and synovial membrane biopsy were performed using arthroscopy in ten subjects suffering from synovial tuberculosis. This was combined with intra-articular isoniazid injection and systemic antituberculosis drugs. In all cases, continuous passive motion exercise was started 2 days after operation and they were followed up from 6 months to 3 years. The flexion angles 90° ± 5° preoperatively increased to 120° ± 14° in nine patients following surgery, the extension limit angle also improved from an average 20° ± 3° preoperatively to 5° ± 1° postoperatively. There was a significant difference in knee function index between preoperation and postoperation ( t = 6.9, t = 6.3, P < 0.01). Japanese Institute of Plastic Surgery synovial disease treatment success criteria was also improved from 44.4 ± 8.4 points before surgery to 81.5 ± 10.4 following surgery ( t = 8.749, P < 0.01) . The joint swelling disappeared or was relieved after 2 months. No relapse of tuberculosis was found at the time of follow-up. Combined use of arthroscopy and antituberculosis medication appears to be advantageous for the management of early-stage synovial tuberculosis of the knee joint. Arthroscopic removal of the pannus allows better nutrition of the cartilage and thus greatly improves the joint function. [ABSTRACT FROM AUTHOR]

Background: Multiple surgical interventions exist for the treatment of symptomatic knee osteoarthritis, but the surgeon and patient may often have difficulty deciding which interventions are the best option. Methods: We conducted a systematic review to identify randomized clinical trials (RCTs) that compared complications, revisions, reoperations, and functional outcomes among TKA (total knee arthroplasty), UKA (unicompartmental knee arthroplasty), HTO (high tibial osteotomy), BCA (bicompartmental knee arthroplasty), BIU (bi-unicompartmental knee arthroplasty), and KJD (knee joint distraction). The PubMed, Embase, and Cochrane databases were reviewed for all studies comparing two or more surgical interventions. Direct-comparison meta-analysis and network meta-analysis (NMA) were performed to combine direct and indirect evidence. The risk of bias was assessed using the revised Cochrane risk of bias tool for RCTs. Results: This NMA and systematic review included 21 studies (17 RCTs), with a total of 1749 patients. The overall risk-of-bias assessment of the RCTs revealed that 7 studies had low risk, 5 had some concerns, and 9 had high risk. SUCRA (the surface under the cumulative ranking curve) rankings revealed that KJD had the greatest risk of appearing postoperative complications, revisions, and reoperations, and UKA or TKA had the lowest risk. The majority of comparisons among various treatments showed no difference for functional outcomes. Conclusion: Each surgical intervention is noninferior to other treatments in functional outcomes, but UKA and TKA are better options to treat OA according to SUCRA rankings by comparing complications, revisions, and reoperations. KJD is an imperfect option for treating OA. Other treatments should be carefully considered for each patient in accordance with their actual conditions. However, this conclusion is limited by the selection of reviewed publications and individual variation of surgical indications for patients. Trial registration: This study was registered with Research Registry (reviewregistry1395). [ABSTRACT FROM AUTHOR]

Background: To minimize the killer turn caused by the sharp margin of the tibial tunnel exit in transtibial PCL reconstruction, surgeons tend to maximize the angle of the tibial tunnel in relation to the tibial plateau. However, to date, no consensus has been reached regarding the maximum angle for the PCL tibial tunnel.Questions/purposes: In this study we sought (1) to determine the maximum tibial tunnel angle for the anteromedial and anterolateral approaches in transtibial PCL reconstruction; (2) to compare the differences in the maximum angle based on three measurement methods: virtual radiographs, CT images, and three-dimensional (3D) knee models; and (3) to conduct a correlation analysis to determine whether patient anthropomorphic factors (age, sex, height, and BMI) are associated with the maximum tibial tunnel angle.Methods: Between January 2018 and December 2020, 625 patients who underwent CT scanning for knee injuries were retrospectively reviewed in our institution. Inclusion criteria were patients 18 to 60 years of age with a Kellgren-Lawrence grade of knee osteoarthritis less than 1 and CT images that clearly showed the PCL tibial attachment. Exclusion criteria were patients with a history of tibial plateau fracture, PCL injuries, tumor, and deformity around the knee. Finally, 104 patients (43 males and 61 females, median age: 38 [range 24 to 56] years, height: 165 ± 9 cm, median BMI: 23 kg/cm2 [range 17 to 31]) were included for analysis. CT data were used to create virtual 3D knee models, and virtual true lateral knee radiographs were obtained by rotating the 3D knee models. Virtual 3D knee models were used as an in vitro standard method to assess the true maximum tibial tunnel angle of anteromedial and anterolateral approaches in transtibial PCL reconstruction. The tibial tunnel's entry was placed 1.5 cm anteromedial and anterolateral to the tibial tubercle for the two approaches. To obtain the maximum angle, a 10-mm- diameter tibial tunnel was simulated by making the tibial tunnel near the posterior tibial cortex. The maximum tibial tunnel angle, tibial tunnel lengths, and perpendicular distances of the tunnel's entry point to the tibial plateau were measured on virtual radiographs, CT images, and virtual 3D knee models. One-way ANOVA was used to compare the differences in the maximum angle among groups, and correlation analysis was performed to identify the relationship of the maximum angle and anthropomorphic factors (age, sex, height, and BMI).Results: The maximum angle of the PCL tibial tunnel relative to the tibial plateau was greater in the anteromedial group than the anterolateral group (58° ± 8° versus 50° ± 8°, mean difference 8° [95% CI 6° to 10°]; p < 0.001). The maximum angle of the PCL tibial tunnel was greater in the virtual radiograph group than the CT image (68° ± 6° versus 49° ± 5°, mean difference 19° [95% CI 17° to 21°]; p < 0.001), the anteromedial approach (68° ± 6° versus 58° ± 8°, mean difference 10° [95% CI 8° to 12°]; p < 0.001), and the anterolateral approach (68° ± 6° versus 50° ± 8°, mean difference 18° [95% CI 16° to 20°]; p < 0.001), but no difference was found between the CT image and the anterolateral groups (49° ± 5° versus 50° ± 8°, mean difference -1° [95% CI -4° to 1°]; p = 0.79). We found no patient anthropomorphic characteristics (age, sex, height, and BMI) that were associated with the maximum angle.Conclusion: Surgeons should note that the mean maximum angle of the tibial tunnel relative to the tibial plateau was greater in the anteromedial than anterolateral approach in PCL reconstruction, and the maximum angle might be overestimated on virtual radiographs and underestimated on CT images.Clinical Relevance: To perform PCL reconstruction more safely, the findings of this study suggest that the PCL drill system should be set differently for the anteromedial and anterolateral approaches, and the maximum angle measured by intraoperative fluoroscopy should be reduced 10° for the anteromedial approach and 18° for the anterolateral approach. Future clinical or cadaveric studies are needed to validate our findings. [ABSTRACT FROM AUTHOR]

Background: Fibrinogen (FIB) has been found to be a promising marker in diagnosing periprosthetic joint infection (PJI), however, the value of FIB in predicting reinfection of PJI is unknown. The purpose of this study was to evaluate the value of FIB in predicting reinfection after debridement, antibiotics, and implant retention (DAIR) for PJI.Methods: We retrospectively analyzed the clinical data of patients who were diagnosed with PJI and underwent DAIR from 2013 to 2019. The levels of the FIB, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) were measured before DAIR. After DAIR, patients were followed and reinfections were identified. For both acute and chronic PJI, the predictive value of FIB was evaluated by calculating the sensitivity, specificity, and area under the curve (AUC) of the receiver operating characteristic curve (ROC), and was compared with traditional inflammatory markers including ESR and CRP.Results: The expression of FIB differed between patients reinfected and those not reinfected in both acute and chronic PJI (p < 0.05). In patients who underwent DAIR for acute PJI, the sensitivity and specificity of FIB were 81.82 and 83.33%, respectively, which were significantly higher than that of CRP (sensitivity, 72.73%; specificity, 50%; p < 0.05), while the specificity was higher than that of ESR (specificity, 41.67%; p < 0.05). In patients who underwent DAIR for chronic PJI, the sensitivity and specificity of FIB were 80.00 and 66.66%, respectively, which were significantly higher than that of CRP (sensitivity, 53.33%; specificity, 66.66%; p < 0.05) and ESR (sensitivity was 66.00%; specificity, 16.66%; p < 0.05). The ROC curves showed that FIB demonstrated the highest AUC among the biomarkers in both acute and chronic PJI.Conclusion: FIB is a promising indicator in predicting reinfection after DAIR for both acute and chronic PJI, and it seems to perform better than ESR and CRP. [ABSTRACT FROM AUTHOR]

To describe the rationale and surgical technique and compare the clinical effect of posterior percutaneous endoscopic cervical discectomy (PPECD) using the Delta system versus that of conventional PPECD (key-hole) surgery for the treatment of symptomatic cervical spondylotic radiculopathy (CSR). A retrospective analysis was performed on 106 single-segment CSR patients between February 2016 and February 2017, 50 of whom underwent conventional PPECD (key-hole), and 56 underwent PPECD using the Delta system. The operative time, intraoperative blood loss, intraoperative complications and postoperative hospital stay were recorded, and the clinical effect was evaluated by the indicators of the Neck Disability Index (NDI), arm-visual analog scale (arm-VAS), neck-VAS, EQ-5D and MacNab classification at the last follow-up. All patients underwent the operation successfully, and 106 patients were followed up. The operative time of the Delta group was 60.47 ± 0.71 min, while the operative time of the key-hole group was 75.46 ± 0.41 min. The difference between the two groups was statistically significant (P < 0.05). However, there was no significant difference between the two groups in terms of blood loss and hospital stay (P > 0.05). The VAS, NDI and EQ-5D scores of the neck and upper limbs in the two groups were significantly better than those before surgery at 1 week after surgery and at the last follow-up (P < 0.05). However, there was no significant difference between the two groups at the last follow-up (P > 0.05). At the last follow-up, there was no significant difference between the two surgical methods when evaluated using the modified MacNab criteria. The imaging results showed that the herniated disc was removed completely and the nerve root was decompressed. The complication rate in the Delta group (3/56, 5.35%) was significantly lower than that in the conventional key-hole group (5/50, 10.0%). PPECD using the Delta system for CSR may be a feasible and promising alternative surgical plan. Compared with the traditional key-hole method, this surgical system can not only provide the surgeon with a larger surgical field of vision but also reduces the operation time and complication rates. [ABSTRACT FROM AUTHOR]

Background: Consistent reference data used for anatomic posterior cruciate ligament (PCL) reconstruction is not well defined. Quantitative guidelines defining the location of PCL attachment would aid in performing anatomic PCL reconstruction. The purpose was to characterize anatomic parameters of the PCL tibial attachment based on magnetic resonance imaging (MRI) in a large population of adult knees.Methods: The PCL tibial attachment site was examined in 736 adult knees with an intact PCL using 3.0-T proton density-weighted sagittal MRI. The outcomes measured were the anterior-posterior diameter (APD) of the tibial plateau; angle between the tibial plateau and the posterior tibial 'shelf' (the slope where the PCL tibial attachment site was) (PTS); length of the PTS; proximal, central, and distal PCL attachment positions as well as the width of the PCL attachment site; and vertical dimension of the PCL attachment site inferior from the tibial plateau.Results: The average APD of the tibia plateau was 33.6 ± 3.5 mm, yielding significant differences between males (35.5 ± 3.0 mm) and females (31.6 ± 2.7 mm), P <.05, and there was a significantly decreasing trend with increasing age in males (P <.05). Mean angle between the tibial plateau and the PTS was 122.4° ± 8.1°, and subgroup analysis showed that the young group had a differently smaller angle (120.9° ± 7.5°) than the middle-aged (123.7° ± 8.2°) and the old (123.4° ± 7.7°) in males population, while there were no significant differences between sexes (P >.05). The proximal, central positions and width of the PCL attachment site were 13.4 ± 3.0 mm, 17.8 ± 3.0 mm and 9.6 ± 2.4 mm along the PTS, with significant differences between males and females (P <.05), and accounted for 60.0 % ± 9.1 %, 80.0 % ± 4.6 % and 43.3 % ± 9.7 % of the PTS respectively, with no significant differences between sexes and among age groups (all P >.05).Conclusions: This study provides reference data of the tibial PCL attachment based on MRI in the sagittal orientation. In analysis of retrospective data from a large population of adult patients, the quantitative values can be used as references to define the inserted angle and depth of the drill guide, and the exact position and size of the tibial PCL tunnel for performing arthroscopic anatomic PCL reconstruction. [ABSTRACT FROM AUTHOR]

Fluid shear stress (FSS) is a ubiquitous mechanical stimulus that potently promotes osteoblast proliferation. Previously, we reported that extracellular signal–regulated kinase 5 (ERK5) is essential for FSS-induced osteoblast proliferation. However, the precise mechanism by which FSS promotes osteoblast proliferation via ERK5 activation is poorly understood. The aim of this study was to determine the critical role of Gαq in FSS-induced ERK5 phosphorylation and osteoblast proliferation, as well as the downstream targets of the Gαq–ERK5 pathway. MC3T3-E1 cells were transfected with 50 nM Gαq siRNA, treated with 5 mM XMD8-92 (a highly selective inhibitor of ERK5 activity), and/or exposed to FSS (12 dyn/cm2). Cell proliferation was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The protein expression levels of Gαq, P-ERK5, ERK5, Cyclin B1, and CDK1 were analyzed by Western blot. Physiological FSS exposure for 60 min remarkably promoted MC3T3-E1 cell proliferation, however, this effect was suppressed by siRNA-mediated Gαq knockdown or inhibition of ERK5 activity by XMD8-92 treatment, suggesting that Gαq and ERK5 might modulate FSS-increased osteoblast proliferation. Furthermore, ERK5 phosphorylation was dramatically inhibited by Gαq siRNA. In addition, our study further revealed that FSS treatment of MC3T3-E1 cells for 60 min markedly upregulated the protein expression levels of Cyclin B1 and CDK1, and this increased expression was predominantly blocked by Gαq siRNA or XMD8-92 treatment. We propose that FSS acts on the Gαq–ERK5 signaling pathway to upregulate Cyclin B1 and CDK1 expression, thereby resulting in MC3T3-E1 cell proliferation. Thus, the Gαq–ERK5 signaling pathway may provide useful information regarding the treatment of bone metabolic disease. [ABSTRACT FROM PUBLISHER]

TNF-α is known to induce osteoblasts apoptosis, whereas mechanical stimulation has been shown to enhance osteoblast survival. In the present study, we found that mechanical stimulation in the form of fluid shear stress (FSS) suppresses TNF-α induced apoptosis in MC3T3-E1 cells. Extracellular signal-regulated kinase 5 (ERK5) is a member of the mitogen-activated protein kinase (MAPK) family that has been implicated in cell survival. We also demonstrated that FSS imposed by flow chamber in vitro leads to a markedly activation of ERK5, which was shown to be protective against TNF-α-induced apoptosis, whereas the transfection of siRNA against ERK5 (ERK5-siRNA) reversed the FSS-medicated anti-apoptotic effects. An initial FSS-mediated activation of ERK5 that phosphorylates AKT to increase its activity, and a following forkhead box O 3a (FoxO3a) was phosphorylated by activated AKT. Phosphorylated FoxO3a is sequestered in the cytoplasm, and prevents it from translocating to nucleus where it can increase the expression of FasL and Bim. The inhibition of AKT-FoxO3a signalings by a PI3K (PI3-kinase)/AKT inhibitor (LY294002) or the transfection of ERK5-siRNA led to the nuclear translocation of non-phosphorylated FoxO3a, and increased the protein expression of FasL and Bim. In addition, the activation of caspase-3 by TNF-α was significantly inhibited by aforementioned FSS-medicated mechanisms. In brief, the activation of ERK5-AKT-FoxO3a signaling pathways by FSS resulted in a decreased expression of FasL and Bim and an inhibition of caspase-3 activation, which exerts a protective effect that prevents osteoblasts from apoptosis. [ABSTRACT FROM AUTHOR]

Fluid shear stress (FSS) is a potent mechanical stimulus and prevents cells from TNF-a-induced apoptosis. Recently, Extracellular-signal-regulated kinase 5 (ERK5) has been found to be involved in regulation of cell survival. However, little is known about the role of ERK5 signaling pathway in FSS-mediated anti-apoptotic effects in osteoblast. In this study, we show that FSS blocks TNF-a-induced apoptosis of MC3T3-E1 cells via ERK5 signaling pathway. We found that physiological FSS for 1 h significantly decreased TNF-α-induced MC3T3-E1 cells apoptosis. After inhibition of ERK5 activity by XMD8-92, a highly-selective inhibitor of ERK5 activity, the ability of FSS to inhibit TNF-α induced apoptosis was significantly decreased. Analysis of anti-apoptotic mechanisms indicated that exposure of MC3T3-E1 cells to FSS for 1 h increased phosphorylation of Bad and inhibited caspase-3 activity. After treatment with XMD8-92, phosphorylation of Bad by FSS was significantly blocked, but caspase-3 activity was increased. In summary, these findings indicated that FSS inhibits TNF-α-mediated signaling events in osteoblast by a mechanism dependent on activation of ERK5, and Bad is a crucial downstream target for ERK5. Those results implied that ERK5 signaling pathway play a crucial role in FSS-mediated anti-apoptotic effect in osteoblast. Thus, ERK5 signaling pathway may be a new drug treatment target of osteoporosis and related bone-wasting diseases. [ABSTRACT FROM AUTHOR]

Radix Hedysari polysaccharides (HPS) is the principal active fraction of Radix Hedysari (RH). The information about HPS3d, the main fraction of HPS3, and its effect on bone is still unknown. In the present study, the purified HPS3d was obtained by anion-exchange column. It consisted of 94.38% polysaccharide, 3.40% protein and 13.30% uronic acid. The molecular weight was measured to be 84.6 kDa. The backbone consisted of galactopyranose and galacturonopyranose, and the side chains were composed of glucopyranose, rhamnopyranose and arabinofuranose. The FT-IR and elemental analysis showed that HPS3d was the sulfated polysaccharide. HPS3d upregulated alkaline phosphatase (ALP) activity and the expression of other osteogenic marker genes in osteoblast. In addition, HPS3d increased the expression and transcriptional activity of Runt-related transcription factor 2 (Runx-2) and Osterix, the two master genes of osteoblast differentiation. These findings suggest that HPS3d stimulates osteoblast differentiation by activation of Runx-2 and Osterix. [ABSTRACT FROM AUTHOR]

NiTi shape memory alloy has been used widely as implanted material; however, possible release of Ni ions may cause toxic, allergic, and potentially carcinogenic effects in a physiological environment. In order to solve this problem, we notice that, as shown by previous studies, anticoagulant heparin is a better material for improving blood biocompatibility. Thus a promising way is to develop new TiO2/heparin coatings on NiTi shape memory alloy, for the purpose of reducing possible release of toxic Ni ions and hence improve hemocompatibility. In this regard, we have fabricated four kinds of hemocompatible coatings: sol-gel TiO2, heating TiO2, sol-gel TiO2/heparin and heating TiO2/heparin on NiTi shape memory alloy. Various measurements have been done against this new material, including FE-SEM, XRD and contact angle tests (used to monitor surface characters), as well as hemolytic tests, dynamic clotting time experiments, platelet binding tests, cell morphology, MTT, ALP and RT-PCR (utilized to investigate blood- and cell-compatibility). Our results reveal that this new material of heparin loaded coatings, as expected, is able to improve the hemocompatibility of NiTi surgical alloy material. Moreover, RT-PCR measurements indicate that the best coating for cell growth is the heating TiO2/heparin. Our results suggest that deposition of TiO2 and heparin coating on the surface of a NiTi alloy sample is a promising method to improve its hemocompatibility. [ABSTRACT FROM AUTHOR]

This paper investigated the biocompatibility of nanoporous TiO2 coating on NiTi shape-memory alloy (SMA) prepared via dealloying method. Our previous study shows that the dealloying treatment at low temperature leads to 130nm Ni-free surface titania surface layer, which possesses good bioactivity because of the combination of hydroxyl (OH-) group in the process of dealloying treatment simultaneously. In this paper, the biological compatibility of NiTi alloy before and after dealloying treatment was evaluated and compared by direct contact method with dermal mesenchymal stem cells (DMSCs) by the isolated culture way. The interrelation between the biological compatibility and surface change of material after modification was systematically analyzed. As a consequence, the dealloying treatment method at low temperature could be of interest for biomedical application, as it can avoid sensitization and allergies and improve biocompatibility of NiTi shape-memory alloys. Thus it laid the foundation of the clinical trials for surface modification of NiTi memory alloy. [ABSTRACT FROM AUTHOR]