Effect of orthopedic insoles on spinal deformity and walking in adolescents with idiopathic scoliosis summary.

Objective: To observe the effects of scoliosis-specific exercise therapy combined with braces and orthopedic insoles on improved spinal deformity and walking ability in adolescents with idiopathic scoliosis (AIS). Method: From September 2019 to September 2020, 60 outpatient AIS patients were distributed into brace group (n = 30) at random and brace combined orthopedic insole group (n = 30). Both groups underwent brace dryness, and the observation group used scoliosis-specific exercise therapy combined with brace therapy, and on this basis, orthopedic insole intervention was added for 8 h per day for 2 months. At the same time, 20 adolescents of the same age with normal spinal development were recruited as a healthy group. GaitScan instruments were used to collect gait and plantar pressure measurements from study subjects. First, the gait and plantar pressure data of AIS patients and healthy groups were compared horizontally to ascertain the abnormal indicators, and then the spinal deformity and the above abnormal indicators were compared between the brace group and the brace combined orthopedic insole group. Outcome: The plantar pressure center drift index (CPEI) in the AIS group was higher than that in the healthy group (F = 3.120, P < 0.05), and there were significant differences in the ratio of medial and lateral heel pressure (M/l) and total foot pressure (P < 0.05) between the AIS group and the healthy group, and no noticeable variations were found in the support phase period, walking speed, and proportion of each phase (P > 0.05). After treatment, the Cobb angle was significantly reduced in both the brace group and the brace combined with orthopedic insole group (P < 0.05), and there was no significant difference between the groups (P > 0.05). There were no significant changes in the pressure ratio of CPEI, M/l and bilateral full foot in the brace group (P > 0.05). The CPEI decreased in the brace combined with orthopedic insole group (P < 0.05), and the pressure ratio of M/l and bilateral full foot tended to 1 (P < 0.05), and was better than that in the brace group (P < 0.05). Conclusion: Patients with AIS may have local and worldwide asymmetric changes in plantar pressure distribution. The addition of orthopedic insoles has limited effect on improving scoliosis deformity in patients with AIS, but it can effectively improve the abnormal biomechanics of patients with AIS, so that the patient's force tends to be balanced.

The association between different physical activity levels and flexion-relaxation phenomenon in women: a cross-sectional study.

BACKGROUND: To investigate whether the flexion-relaxation phenomenon differs in women with different physical activity levels. METHODS: Seventy-two subjects were recruited for this study. The electromyographic activity of the erector spinae and multifidus muscles was recorded during a flexion task using a surface electromyographic device. The flexion-relaxation and extension-relaxation ratios were calculated. Participants were classified into different physical activity level groups based on their responses to the International Physical Activity Questionnaire. A Welch analysis of variance was conducted to compare the flexion-relaxation ratio and extension-relaxation ratio between groups. RESULTS: A significant difference in the flexion-relaxation and extension-relaxation ratio was observed in both the erector spinae and multifidus muscles between different levels of physical activity. CONCLUSIONS: In this study, we observed that female participants with high levels of physical activity showed a more pronounced flexion-relaxation phenomenon compared to those with moderate and low levels of physical activity. No significant difference was found between moderate and low physical activity levels. The findings of our study highlight the association between physical activity and the mechanics of the spinal stabilising muscles.

Surface Modification with NGF-Loaded Chitosan/Heparin Nanoparticles for Improving Biocompatibility of Cardiovascular Stent.

Late thrombosis and restenosis remain major challenges to the safety of drug-eluting stents. Biofunctional modification to endow the surface with selective anticoagulation and promote endothelium regeneration has become a hotpot recently. In this study, chitosan and heparin were found to form three-dimensional nanoparticles by spontaneous electrostatic interaction. Based on the specific binding properties between heparin and nerve growth factor (NGF), a new type of NGF-loaded heparin/chitosan nanoparticles was constructed for surface modification. The results of material characterization show that the nanoparticles are successfully immobilized on the surface of the material. In vitro blood compatibility and endothelial cell compatibility assay showed that the modified surface could selectively inhibit platelet adhesion and smooth muscle cell overproliferation, while accelerating endothelialization via promoting endothelial cell proliferation and enhancing endothelial progenitor cell mobilization.

Enhanced Effect of Tendon Stem/Progenitor Cells Combined With Tendon-Derived Decellularized Extracellular Matrix on Tendon Regeneration.

Decellularized extracellular matrices have been clinically used for tendon regeneration. However, only a few systematic studies have compared tendon stem/progenitor cells to mesenchymal stromal cells on the tendon-derived decellularized matrix. In the present study, we prepared extracellular matrix derived from porcine tendons and seeded with tendon stem/progenitor cells, embryonic stem cell-derived mesenchymal stromal cells or without stem cells. Then we implanted the mixture (composed of stem cells and scaffold) into the defect of a rat Achilles tendon. Next, 4 weeks post-surgery the regenerated tendon tissue was collected. Histological staining, immunohistochemistry, determination of collagen content, transmission electron microscopy, and biomechanical testing were performed to evaluate the tendon structure and biomechanical properties. Our study collectively demonstrated that decellularized extracellular matrix derived from porcine tendons significantly promoted the regeneration of injured tendons when combined with tendon stem/progenitor cells or embryonic stem cell-mesenchymal stromal cells. Compared to embryonic stem cell-mesenchymal stromal cells, tendon stem/progenitor cells combined with decellularized matrix showed more improvement in the structural and biomechanical properties of regenerated tendons in vivo. These findings suggest a promising strategy for functional tendon tissue regeneration and further studies are warranted to develop a functional tendon tissue regeneration utilizing tendon stem/progenitor cells integrated with a tendon-derived decellularized matrix.

Cytotoxicity of local anesthetics on rabbit adipose-derived mesenchymal stem cells during early chondrogenic differentiation.

Local anesthetics (LAs) are commonly used to provide peri-operative pain control in the peripheral joints. In the field of regenerative medicine, adipose-derived mesenchymal stem cells (ADMSCs) are gaining attention as a cellular source for repair and regeneration in degenerative diseases. However, previous studies have demonstrated that the commonly used drugs lidocaine, ropivacaine, bupivacaine and mepivacaine may be toxic to human chondrocytes, which has raised concerns over whether they exert similar negative effects on ADMSCs during early chondrogenic differentiation. In the present in vitro study, the cytotoxicity of different LAs to ADMSCs was determined during early chondrogenic differentiation. At concentrations similar to those after physiological dilution once injected into the degenerative tissues, LAs (1% lidocaine, 0.5% bupivacaine, 0.5% ropivacaine or 2% mepivacaine) and PBS (control group) were incubated with rabbit ADMSCs (rADMSCs) for 60 min. Following further culture for 3 or 7 days, the cell viability, apoptosis and morphological alterations of chondrogenic differentiation were measured by determining the mitochondrial activity, by flow cytometric analysis, Safranine Fast Green double staining and reverse transcription-quantitative polymerase chain reaction of chondrogenesis-associated genes. The results indicated that the mitochondrial activity in rADMSC was decreased and the apoptotic rate was increased, following treatment with LAs (P<0.05). Lidocaine (1%) was less cytotoxic to rADMSCs during early chondrogenesis compared with other LAs. The expression levels of chondrogenesis-associated markers, including collagen I, collagen III and sex-determining region Y box 9 were all decreased at day 3 following exposure to LAs compared with the control group (P<0.05). The expression levels of these chondrogenesis-associated genes began to increase on day 7 following exposure but remained lower compared with the control group (P<0.05). Of note, 2% mepivacaine and 1% lidocaine exhibited a less pronounced negative effect on chondrogenesis-associated gene expression compared with other LAs. Therefore, the present study concluded that LAs are cytotoxic to rADMSCs during early chondrogenesis. Attention should be paid to the different types of LA selected in conjunction with ADMSC injection therapy.