Effect of immersive virtual mirror visual feedback on Mu suppression and coherence in motor and parietal cortex in stroke.

We investigated the activation pattern of the motor cortex (M1) and parietal cortex during immersive virtual reality (VR)-based mirror visual feedback (MVF) of the upper limb in 14 patients with chronic stroke and severe upper limb hemiparesis and in 21 healthy controls. Participants performed wrist extension with unaffected wrists (dominant side in controls). In the MVF condition, movement of the affected hand was synchronized with that of the unaffected hand. In the no-MVF condition, only the movement of unaffected hand was shown. Mu suppression in bilateral M1 and parietal cortex and mu coherence were analyzed. In patients with stroke, MVF induced significant mu suppression in both the ipsilesional M1 and parietal lobes (p = 0.006 and p = 0.009, respectively), while mu suppression was observed in the bilateral M1 (p = 0.003 for ipsilesional and p = 0.041 for contralesional M1, respectively) and contralesional parietal lobes in the controls (p = 0.036). The ipsilesional mu coherence between the M1 and parietal cortex in patients with stroke was stronger than controls, regardless of MVF condition (p < 0.001), while mu coherence between interhemispheric M1 cortices was significantly weaker in patients with stroke (p = 0.032). Our findings provide evidence of the neural mechanism of MVF using immersive VR in patients with stroke.

Altered Functional Networks of Alpha and Low-Beta Bands During Upper Limb Movement and Association with Motor Impairment in Chronic Stroke.

Background: Impaired movement after stroke is closely associated with altered brain functions, and thus the investigation on neural substrates of patients with stroke can pave a way for not only understanding the underlying mechanisms of neuropathological traits, but also providing an innovative solution for stroke rehabilitation. The objective of this study was to precisely investigate altered brain functions in terms of power spectral and brain network analyses. Methods: Altered brain function was investigated by using electroencephalography (EEG) measured while 34 patients with chronic stroke performed movement tasks with the affected and unaffected hands. The relationships between functional brain network indices and Fugl-Meyer Assessment (FMA) scores were also investigated. Results: A stronger low-beta event-related desynchronization was found in the contralesional hemisphere for both affected and unaffected movement tasks compared with that of the ipsilesional hemisphere. More efficient whole-brain networks (increased strength and clustering coefficient, and prolonged path length) in the low-beta frequency band were revealed when moving the unaffected hand compared with when moving the affected hand. In addition, the brain network indices of the contralesional hemisphere indicated higher efficiency and cost-effectiveness than those of the ipsilesional hemisphere in both the alpha and low-beta frequency bands. Moreover, the alpha network indices (strength, clustering coefficient, path length, and small-worldness) were significantly correlated with the FMA scores. Conclusions: Efficient functional brain network indices are associated with better motor outcomes in patients with stroke and could be useful biomarkers to monitor stroke recovery during rehabilitation.

A randomized controlled trial of stem cell injection for tendon tear.

Tendons have limited reparative ability and perform a relatively simple mechanical function via the extracellular matrix. Thus, the injured tendon might be treated successfully by stem cell transplantation. We performed a randomized, controlled study to investigate the effects of mesenchymal stem cell injection for treating partial tears in the supraspinatus tendon. We enrolled 24 patients with shoulder pain lasting more than 3 months and partial tears in the supraspinatus tendon. Participants were assigned to three groups: stem cells in fibrin glue, normal saline/fibrin glue mixture, and normal saline only, with which intra-lesional injection was performed. Pain at activity and rest, shoulder function and tear size were evaluated. For safety measures, laboratory tests were taken and adverse events were recorded at every visit. Participants were followed up at 6, 12 weeks, 6, 12 months and 2 years after injection. The primary outcome measure was the improvement in pain at activity at 3 months after injection. Twenty-three patients were included in the final analysis. Primary outcome did not differ among groups (p = 0.35). A mixed effect model revealed no statistically significant interactions. Only time significantly predicted the outcome measure. All participants reported transient pain at the injection site. There were no differences in post-injection pain duration or severity. Safety measures did not differ between groups, and there were no persistent adverse events. Stem cell injection into supraspinatus partial tears in patients with shoulder pain lasting more than 3 months was not more effective than control injections.ClinicalTrials.gov Identifier: NCT02298023.

The relationships between low back pain and lumbar lordosis: a systematic review and meta-analysis.

BACKGROUND CONTEXT: Clinicians regard lumbar lordotic curvature (LLC) with respect to low back pain (LBP) in a contradictory fashion. The time-honored point of view is that LLC itself, or its increment, causes LBP. On the other hand, recently, the biomechanical role of LLC has been emphasized, and loss of lordosis is considered a possible cause of LBP. The relationship between LLC and LBP has immense clinical significance, because it serves as the basis of therapeutic exercises for treating and preventing LBP. PURPOSE: This study aimed to (1) determine the difference in LLC in those with and without LBP and (2) investigate confounding factors that might affect the association between LLC and LBP. STUDY DESIGN: Systematic review and meta-analysis. PATIENT SAMPLE: The inclusion criteria consisted of observational studies that included information on lumbar lordotic angle (LLA) assessed by radiological image, in both patients with LBP and healthy controls. Studies solely involving pediatric populations, or addressing spinal conditions of nondegenerative causes, were excluded. METHODS: A systematic electronic search of Medline, Embase, Cochrane Library, CINAHL, Scopus, PEDro, and Web of Science using terms related to lumbar alignment and Boolean logic was performed: (lumbar lordo*) or (lumbar alignment) or (sagittal alignment) or (sagittal balance). Standardized mean differences (SMD) and 95% confidence intervals (CI) were estimated, and chi-square and I2 statistics were used to assess within-group heterogeneity by random effects model. Additionally, the age and gender of participants, spinal disease entity, and the severity and duration of LBP were evaluated as possible confounding factors. RESULTS: A total of 13 studies consisting of 796 patients with LBP and 927 healthy controls were identified. Overall, patients with LBP tended to have smaller LLA than healthy controls. However, the studies were heterogeneous. In the meta-regression analysis, the factors of age, severity of LBP, and spinal disease entity were revealed to contribute significantly to variance between studies. In the subgroup analysis of the five studies that compared patients with disc herniation or degeneration with healthy controls, patients with LBP had smaller LLA (SMD: -0.94, 95% CI: -1.19 to -0.69), with sufficient homogeneity based on significance level of .1 (I2=45.7%, p=.118). In the six age-matched studies, patients with LBP had smaller LLA than healthy controls (SMD: -0.33, 95% CI: -0.46 to -0.21), without statistical heterogeneity (I2=0%, p=.916). CONCLUSIONS: This meta-analysis demonstrates a strong relationship between LBP and decreased LLC, especially when compared with age-matched healthy controls. Among specific diseases, LBP by disc herniation or degeneration was shown to be substantially associated with the loss of LLC.

Crystallization of Local Anesthetics When Mixed With Corticosteroid Solutions.

OBJECTIVE: To evaluate at which pH level various local anesthetics precipitate, and to confirm which combination of corticosteroid and local anesthetic crystallizes. METHODS: Each of ropivacaine-HCl, bupivacaine-HCl, and lidocaine-HCl was mixed with 4 different concentrations of NaOH solutions. Also, each of the three local anesthetics was mixed with the same volume of 3 corticosteroid solutions (triamcinolone acetonide, dexamethasone sodium phosphate, and betamethasone sodium phosphate). Precipitation of the local anesthetics (or not) was observed, by the naked eye and by microscope. The pH of each solution and the size of the precipitated crystal were measured. RESULTS: Alkalinized with NaOH to a certain value of pH, local anesthetics precipitated (ropivacaine pH 6.9, bupivacaine pH 7.7, and lidocaine pH 12.9). Precipitation was observed as a cloudy appearance by the naked eye and as the aggregation of small particles (<10 µm) by microscope. The amount of particles and aggregation increased with increased pH. Mixed with betamethasone sodium phosphate, ropivacaine was precipitated in the form of numerous large crystals (>300 µm, pH 7.5). Ropivacaine with dexamethasone sodium phosphate also precipitated, but it was only observable by microscope (a few crystals of 10-100 µm, pH 7.0). Bupivacaine with betamethasone sodium phosphate formed precipitates of non-aggregated smaller particles (<10 µm, pH 7.7). Lidocaine mixed with corticosteroids did not precipitate. CONCLUSION: Ropivacaine and bupivacaine can precipitate by alkalinization at a physiological pH, and therefore also produce crystals at a physiological pH when they are mixed with betamethasone sodium phosphate. Thus, the potential risk should be noted for their use in interventions, such as epidural steroid injections.

Treatment of Lateral Epicondylosis by Using Allogeneic Adipose-Derived Mesenchymal Stem Cells: A Pilot Study.

Mesenchymal stem cell therapy is a novel regenerative approach for treating tendinopathy. Here, we evaluated the safety and efficacy of allogeneic adipose-derived mesenchymal stem cells (allo-ASC) in treating lateral epicondylosis (LE). Under ultrasound guidance, allo-ASCs mixed with fibrin glue were injected into the hypoechoic common extensor tendon lesions of 12 participants with chronic LE; 6 subjects each were administered 10(6) or 10(7) cells in 1 ml. Safety was evaluated at day 3 and weeks 2, 6, 12, 26, and 52 post-injection. Efficacy was assessed by measuring patients' visual analog scale (VAS) score for elbow pain, modified Mayo clinic performance index for the elbow, and by evaluating longitudinal and transverse ultrasound images of tendon defect areas after 6, 12, 26, and 52 weeks. No significant adverse effects of allo-ASC injection were observed through 52 weeks of follow-up. From baseline through 52 weeks of periodic follow-up, VAS scores progressively decreased from 66.8 ± 14.5 mm to 14.8 ± 13.1 mm and elbow performance scores improved from 64.0 ± 13.5 to 90.6 ± 5.8. Tendon defects also significantly decreased through this period. Allo-ASC therapy was thus safe and effective in improving elbow pain, performance, and structural defects for 52 weeks. This clinical study is the first to reveal therapeutic value of mesenchymal stem cell injection for treating chronic tendinopathy.

Noninvasive DC stimulation on neck changes MEP.

Direct current stimulation (DCS) has been known as a noninvasive method for modulating neural activity. We estimated the effects of noninvasive cutaneous DCS applied to the cervical region on corticospinal excitability and segmental sensorimotor excitability. The motor-evoked potential amplitudes and the parameters of the Hoffmann reflex were measured before, immediately after, 1 h after, and 2 h after DCS. In this study, we found that noninvasive cervical application of DCS could increase the motor-evoked potential amplitudes which reflected corticospinal tract excitability. This effect of DCS remained for 2 h after stimulation had ceased. These findings suggest DCS might be a noninvasive and effective tool for corticospinal tract excitation.