Low back pain among Italian runners: A cross-sectional survey.

BACKGROUND: Low Back Pain (LBP) is commonly reported as a very frequent disorder in sports, but its prevalence in runners remains unclear. OBJECTIVES: To determine the prevalence of LBP in a wide sample of Italian runners. DESIGN: A cross-sectional online survey. SETTING: A national survey, according to the CHERRIES and STROBE guidelines, was performed in 2019. PARTICIPANTS: 2539 Italian runners. METHODS: A sample of Italian runners registered with national running associations was recruited. The survey was conducted using an online survey development platform. The questionnaire was self-reported and included 38 questions. MAIN OUTCOME MEASURES: Descriptive statistics and frequencies were used to analyze results. Relationships between demographics, daily habits and running characteristics and the responses given was calculated with Cramer's V. Only correlation values higher >0.60 were deemed of interest. RESULTS: 2539 questionnaires (63.5%) were valid for analysis. In total, 22.6% of runners reported having experienced LBP in the past year. Most participants (77.0%) reporting episodes of LBP believed it was not caused by running. No significant correlations (Cramer's V < 0.60) were found between LBP and demographics, training characteristics or lifestyle habits. CONCLUSION: The prevalence of LBP among Italian runners was 22,57%. LBP was not associated with training, equipment or lifestyle.

Alterations in jaw clenching force control in people with myogenic temporomandibular disorders.

Isometric bite force control, via measures of force accuracy, force steadiness and force proprioception, was assessed in patients with myogenic temporomandibular disorders (TMDs) compared to healthy controls. Twelve people with myogenic TMDs and twelve age- and gender-matched asymptomatic controls performed maximal voluntary contractions (MVC) of unilateral jaw clenching followed by submaximal isometric contractions, with and without visual feedback of force, at 10, 30 50% and 70% MVC. Force performance was assessed with indices of accuracy (mean distance, MD) and precision (standard deviation, SD) and reported as a percentage of the MVC. A mixed-effect model was used to evaluate differences in MVC, MD and SD. The MVC was lower in the TMD group when clenching either ipsilateral or contralateral to the side of greatest pain (p < 0.05). No difference in MD was observed between groups. The SD depended on the interaction between group and painful side (p = 0.04) with the TMD group displaying higher SD when executing the task with the most painful side when compared to the ipsilateral or contralateral sides of the control group. The reduced maximal bite force and force steadiness observed in people with myogenic pain may interfere with masticatory function and should be considered when planning therapeutic interventions for TMDs.

Effect of fluid shear stress on the permeability of the arterial endothelium.

The localization of atherosclerotic lesions is due, in part, to regional variations in the permeability of arterial endothelium to macromolecules. In turn, endothelial permeability may be influenced by fluid shear stresses. The spatial variation in endothelial permeability is reviewed and evidence for shear stress dependence upon permeability is presented. These results are examined in light of various signaling mechanisms that increase permeability by increasing the transport of water and macromolecules through the junctions separating endothelial cells. Signaling pathways cause a change in the dense peripheral band of actin and actin stress fibers or alter the phosphorylation of junction proteins which affects their ability to localize in junctions. Future directions to clarify the effect of shear stress on permeability are considered.