The Disease-Modifying Effects of a Single Intra-Articular Corticosteroid Injection during the Freezing Phase of Frozen Shoulder in an Animal Model.

Although frequently prescribed for frozen shoulder, it is not known if corticosteroid injections improve the course of frozen shoulder. This study aimed to assess the disease-modifying effects of an intra-articular corticosteroid administration at the freezing phase of frozen shoulder. Twenty-four Sprague-Dawley rats were divided into four groups. Their unilateral shoulders were immobilized for the first 3 days in all groups, followed by an intra-articular corticosteroid injection in Group A, an injection and the cessation of immobilization in Group B, no further intervention in Group C, and the cessation of immobilization in Group D. All rats were sacrificed in Week 3 of study, at which point the passive shoulder abduction angles were measured and the axillary recess tissues were retrieved for histological and Western blot analyses. The passive shoulder abduction angles at the time of sacrifice were 138° ± 8° (Group A), 146° ± 5° (Group B), 95° ± 11° (Group C), 132° ± 8° (Group D), and 158° ± 2° (Control). The histological assessments and Western blots showed greater fibrosis and inflammation in the groups that did not receive the corticosteroid injection (Groups C and D) compared to the corticosteroid-injected groups (Groups A and B). These findings demonstrate the anti-inflammatory and disease-modifying effects of corticosteroid injections during the freezing phase of frozen shoulder in an animal model.

Efficacy of Intra-articular Triamcinolone and Hyaluronic Acid in a Frozen Shoulder Rat Model.

BACKGROUND: Intra-articular corticosteroid or hyaluronic acid (HA) is commonly prescribed for frozen shoulder. However, few studies have investigated histological and molecular changes after injection. PURPOSE: To compare the effectiveness of intra-articular injections of triamcinolone and HA in a frozen shoulder rat model and verify a greater effect of triamcinolone in passive shoulder abduction compared with HA. STUDY DESIGN: Controlled laboratory study. METHODS: Twenty male Sprague-Dawley rats were randomly allocated into 4 groups (n = 5 in each): control group, which did not receive cast immobilization or injection, and 3 experimental groups, which received 3 weeks of unilateral shoulder immobilization followed by intra-articular injections (normal saline, triamcinolone, or HA) at the immobilized shoulder. Passive shoulder abduction angle, histological and immunohistochemical staining, and Western blotting results were assessed 2 weeks after injection. The intensity and extent of staining were converted to semiquantitative scores for further analysis. RESULTS: Shoulder abduction angles before sacrifice were 153.0°± 2.7° (control group), 107.0°± 5.7° (saline group), 139.0°± 9.6° (triamcinoline group), and 110.0°± 10.6° (HA group), showing significant differences between control and saline groups, control and HA groups, saline and triamcinoline groups, and triamcinoline and HA groups (P < .001) but not between control and triamcinoline groups (P = .053). Histologic evaluation revealed an increase in synovial folds and thickening of the capsular membrane in the saline and HA groups; this change was not evident in the triamcinolone group. A comparison of semiquantitative scores revealed greater expression levels of proteins involved in fibrosis and angiogenesis in the saline and HA groups compared with the control and triamcinolone groups. In Western blotting, the expression of inflammatory cytokines and the receptor for advanced glycation end products was significantly lower in the triamcinolone and HA groups than in the saline group. CONCLUSION: Triamcinolone injection was more effective than normal saline or HA injection in improving range of motion and reversing fibrotic and angiogenic features of frozen shoulder. Both triamcinolone and HA injections elicited anti-inflammatory effects. CLINICAL RELEVANCE: The antifibrotic and antiangiogenic properties of triamcinolone and the anti-inflammatory properties of both triamcinolone and HA should be considered when performing injections in clinical settings.

Comparing the Lower-Limb Muscle Activation Patterns of Simulated Walking Using an End-Effector-Type Robot with Real Level and Stair Walking in Children with Spastic Bilateral Cerebral Palsy.

Cerebral palsy is a neurologic disorder caused by lesions on an immature brain, often resulting in spasticity and gait abnormality. This study aimed to compare the muscle activation patterns of real level and stair walking with those of simulated walking using an end-effector-type robot in children with spastic cerebral palsy. The electromyographic activities of the vastus lateralis, biceps femoris, tibialis anterior and medial gastrocnemius of nine children with spastic bilateral cerebral palsy were measured during gait using a wireless surface EMG device. Morning walk was used for the simulated gait. Differences in the muscle activation patterns between the real and simulated gait conditions were analyzed. In the loading response, all four muscles showed reduced activity during two simulated conditions. In mid-stance, mGCM showed reduced activity during simulated conditions, whereas BFem showed greater activity during simulated level walking. In the swing phase, BFem and TAnt activity was reduced during the simulated conditions. The onset-offset of the VLat, BFem and TAnt activity was significantly delayed during simulated versus real level walking. No differences in activity onset-offset were observed between the simulated level and stair conditions. In conclusion, the robot-simulated gait showed differences in its muscle activation patterns compared with the real gait conditions, which must be considered for gait training using an end-effector-type robot.

Simple and Sensitive Detection of Bacterial Hydrogen Sulfide Production Using a Paper-Based Colorimetric Assay.

Hydrogen sulfide (H2S) is known to participate in bacteria-induced inflammatory response in periodontal diseases. Therefore, it is necessary to quantify H2S produced by oral bacteria for diagnosis and treatment of oral diseases including halitosis and periodontal disease. In this study, we introduce a paper-based colorimetric assay for detecting bacterial H2S utilizing silver/Nafion/polyvinylpyrrolidone membrane and a 96-well microplate. This H2S-sensing paper showed a good sensitivity (8.27 blue channel intensity/µM H2S, R2 = 0.9996), which was higher than that of lead acetate paper (6.05 blue channel intensity/µM H2S, R2 = 0.9959). We analyzed the difference in H2S concentration released from four kinds of oral bacteria (Eikenella corrodens, Streptococcus sobrinus, Streptococcus mutans, and Lactobacillus casei). Finally, the H2S level in Eikenella corrodens while varying the concentration of cysteine and treatment time was quantified. This paper-based colorimetric assay can be utilized as a simple and effective tool for in vitro screening of H2S-producing ability of many bacteria as well as salivary H2S analysis.

Gait Adaptation Is Different between the Affected and Unaffected Legs in Children with Spastic Hemiplegic Cerebral Palsy While Walking on a Changing Slope.

Walking on sloped surfaces requires additional effort; how individuals with spastic hemiplegic cerebral palsy (CP) manage their gait on slopes remains unknown. Herein, we analyzed the difference in gait adaptation between the affected and unaffected legs according to changes in the incline by measuring spatiotemporal and kinematic data in children with spastic hemiplegic CP. Seventeen children underwent instrumented three-dimensional gait analysis on a dynamic pitch treadmill at an incline of +10° to -10° (intervals of 5°). While the step length of the affected legs increased during uphill gait and decreased during downhill gait, the unaffected legs showed no significance. During uphill gait, the hip, knee, and ankle joints of the affected and unaffected legs showed increased flexion, while the unaffected leg showed increased knee flexion throughout most of the stance phase compared with the affected leg. During downhill gait, hip and knee flexion increased in the affected leg, and knee flexion increased in the unaffected leg during the early swing phase. However, the ankle plantar flexion increased during the stance phase only in the unaffected leg. Although alterations in temporospatial variables and joint kinematics occurred in both legs as the slope angle changed, they showed different adaptation mechanisms.

The Contribution of Neighborhood Tree and Greenspace to Asthma Emergency Room Visits: An Application of Advanced Spatial Data in Los Angeles County.

This paper aims to investigate the role of neighborhood tree and greenspace on asthma morbidity, especially asthma emergency room visits. We employed advanced spatial data which allow for precisely capturing both the quantity and the features of tree and greenspace within a neighborhood environment. The results from the spatial regression models in Los Angeles County revealed that the features of trees and greenspace, such as the configuration of the tree canopy, the level of tree clustering, and private neighborhood greenspaces contribute to decreasing asthma morbidity, in addition to the quantity of tree and greenspace acreages. Notably, however, large scale greenspace, such as golf courses, school playgrounds, and parks fails to reduce the number of asthma emergency room visits at the statistically significant level. These findings imply that the creation of dense or clustered tree patches and small-scale neighborhood greenspaces might play a substantial role in mitigating air quality and consequently reducing asthma emergency room visits.