Trpm5 channels encode bistability of spinal motoneurons and ensure motor control of hindlimbs in mice

Bistable motoneurons of the spinal cord exhibit warmth-activated plateau potential driven by Na+ and triggered by a brief excitation. The thermoregulating molecular mechanisms of bistability and their role in motor functions remain unknown. Here, we identify thermosensitive Na+-permeable Trpm5 channels as the main molecular players for bistability in mouse motoneurons. Pharmacological, genetic or computational inhibition of Trpm5 occlude bistable-related properties (slow afterdepolarization, windup, plateau potentials) and reduce spinal locomotor outputs while central pattern generators for locomotion operate normally. At cellular level, Trpm5 is activated by a ryanodine-mediated Ca2+ release and turned off by Ca2+ reuptake through the sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) pump. Mice in which Trpm5 is genetically silenced in most lumbar motoneurons develop hindlimb paresis and show difficulties in executing high-demanding locomotor tasks. Overall, by encoding bistability in motoneurons, Trpm5 appears indispensable for producing a postural tone in hindlimbs and amplifying the locomotor output.

Posture and Health: Are the Biomechanical Postural Evaluation and the Postural Evaluation Questionnaire Comparable to and Predictive of the Digitized Biometrics Examination?

Background: Postural tone alterations are expressions of myofascial and, therefore, of structural, visceral, and emotional disorders. To prevent these disorders, this study proposes a quantitative investigation method which administers a postural evaluation questionnaire and a postural biomechanical evaluation to 100 healthy subjects. Methods: The reliability of the method is studied by comparing both assessments with digitized biometrics. In addition, 50 subjects undergo the biomechanical evaluation form twice, by four different operators, to study the intraoperative repeatability. Results: The results show a satisfactory overlap between the results obtained with the postural evaluation questionnaire and the postural biomechanical evaluation compared to computerized biometrics. Furthermore, intraoperative repeatability in the use of the biomechanical evaluation form is demonstrated thanks to a minimal margin of error. Conclusions: This experience suggests the importance of undertaking this path in both the curative and the preventive sphere on a large scale and on different types of people who easily, and even unknowingly, may face dysfunctional syndromes, not only structural and myofascial but also consequently of the entire body’s homeostasis.

Abdominothoracic Postural Tone Influences the Sensations Induced by Meal Ingestion

Postprandial objective abdominal distention is frequently associated with a subjective sensation of abdominal bloating, but the relation between both complaints is unknown. While the bloating sensation has a visceral origin, abdominal distention is a behavioral somatic response, involving contraction and descent of the diaphragm with protrusion of the anterior abdominal wall. Our aim was to determine whether abdominal distention influences digestive sensations. In 16 healthy women we investigated the effect of intentional abdominal distention on experimentally induced bloating sensation (by a meal overload). Participants were first taught to produce diaphragmatic contraction and visible abdominal distention. After a meal overload, sensations of bloating (0 to 10) and digestive well-being (−5 to + 5) were measured during 30-s. maneuvers alternating diaphragmatic contraction and diaphragmatic relaxation. Compared to diaphragmatic relaxation, diaphragmatic contraction was associated with diaphragmatic descent (by 21 + 3 mm; p < 0.001), objective abdominal distension (32 + 5 mm girth increase; p = 0.001), more intense sensation of bloating (7.3 + 0.4 vs. 8.0 + 0.4 score; p = 0.010) and lower digestive well-being (−0.9 + 0.5 vs. −1.9 + 0.5 score; p = 0.028). These results indicate that somatic postural tone underlying abdominal distention worsens the perception of visceral sensations (ClinicalTrials.gov ID: NCT04691882).

Potential Mechanisms of the Alexander Technique: Toward a Comprehensive Neurophysiological Model

The Alexander technique (AT) has been practiced for over 125 years. Despite evidence of its clinical utility, a clear explanation of how AT works is lacking, as the foundational science needed to test the underlying ideas has only recently become available. The authors propose that the core changes brought about by Alexander training are improvements in the adaptivity and distribution of postural tone, along with changes in body schema, and that these changes underlie many of the reported benefits. They suggest that AT alters tone and body schema via spatial attention and executive processes, which in turn affect low-level motor elements. To engage these pathways, AT strategically engages attention, intention, and inhibition, along with haptic communication. The uniqueness of the approach comes from the way these elements are woven together. Evidence for the contribution of these elements is discussed, drawing on direct studies of AT and other relevant modern scientific literature.

The role of postural control in physical activity

Background: Postural control concerns control of body position in space in two aspects: 1. stability that is understood as ability to maintain projection of center of gravity on support surface 2. orientation understood as proper relation of individual body segments towards each other and towards surrounding In pediatric physiotherapy different term is used that constitute synonym of postural control - it is postural reflex mechanism of which the most important factor is postural tone Aim of study: To determine relation between postural control and moderate physical activity in children? Material/Methods: Method used in the study encompasses physiotherapeutic assessment of postural control before and after two weeks period of moderate physical activity. It included multi-sport activities (with prevalence of activities with use of water equipment), that stimulate postural control. 23 children (11 girls and 12 boys) aged 7-16 were examined. Their postural control was assessed with use of two parameters: size of postural tone (Postural Tone Coefficient) and body stabilization (Body Stabilization Test). Obtained results were processed statistically Results: After two weeks of moderate physical activity, parameters that concern postural control were improved. In the statistical analyze improvement appears to be statistically significant on the level of p < 0,05. Conclusions: Moderate physical activity influences postural control improvement.

Management of syncope: from evidence to clinical practice

Syncope is defined as a transient loss of consciousness (T-LOC) due to temporary global cerebral hypoperfusion. It is characterized by rapid onset, short duration, loss of postural tone possibly causing patient fall, and spontaneous full recovery. Syncope has a high prevalence and incidence within the general population with a relevant impact on both quality of life and health care costs. The diagnosis of syncope is often inaccurate and subject to delay, and management is greatly variable. The main objective of this monograph is to discuss a methodological diagnostic approach to signs and symptoms suggestive of syncope, aiming for a management optimization. The present work is based on a systematic review of recent international guidelines.

Effect of holiday on postural tone and selected parameters of body posture in young people with Down syndrome

Background: Regular physical therapy of people with Down syndrome improves the efficiency of such treatment. However, it remains unclear whether a discontinuation of the therapy over the period of summer holiday influences the effects of the therapeutic process. The aim of this study was to evaluate the effect of summer holiday on postural tone and quantitative parameters of body posture (angle of trunk rotation in the transverse plane and the spinal curvatures such as kyphosis or lordosis in the sagittal plane) in young people with Down syndrome.Material/Methods: Twenty one people aged 14 to 24 years were examined, with IQ scores from 54 to 35 on the Wechsler Intelligence scale. The experimental group was young people with Down syndrome whereas the control group were people with moderate intellectual disability without additional neurological, orthopaedic and other genetic disorders. The postural tone coefficient (PTC) and values of the spinal curvature (lordosis and kyphosis) and angle of trunk rotation (ATR) were evaluated twice. The first measurement was performed after 10 months of regular neurorehabilitation according to the neurodevelopment concept while the second - after 2 months of summer holiday.Results: During the holiday, the PTC value reduced significantly in the controls, from 0.40 to 0.37 (p=0.02), whereas in young people with Down syndrome, postural tone did not change significantly (p=0.33). In terms of the parameters of body posture, one significant change was observed in the group of patients with Down syndrome (kyphosis, p=0.00).Conclusions: No significant correlations were found between postural tone and values of kyphosis, lordosis and angle of trunk rotation, except for the relationship between PTC and angle of trunk rotation obtained in the main thoracic measurement (Th5- Th12, p=0.03).

Influence of Asymmetrical Tonic Neck Reflex on motor development of infants with hypotony of posture

Introduction: One of the commonly used terms in the assessment of CNS functioning is muscle tone. In literature we can find many different and not standardized definitions. Postural tone depends on topographic distribution in proximal and distal parts of body and antigravital activity. For diagnostic and therapeutic purpose the term postural tone is used. The aim of this study was to assess (monitoring) the psychomotor development of infants between 2 months and 2 years of life with abnormal posture tone (hypotonia of posture) and asymmetry of postural and motor patterns. Infants participated in NDT-Bobath therapeutic intervention. Material and methods: 65 infants fulfilling specified criteria were examined during 2 years of prospective study. According to hypotonic type, infants were divided into two groups. The presence of asymmetrical tonic neck activity in spontaneous movements was coded in two-points scale (1 or 2). Results: All infants were examined at first visit with INSITE developmental scale which displayed psychomotor retardation. At the age of 2 years, only 21,87% from first group and 100% from second group still were assessed as retarded. Conclusions: Disintegrated activity ATOS decreased the level of motor development of 24-month-old infants even to 4 months of developmental age. In the second group, the number of infants with more disorders in quality of movement and decreased final developmental age is much bigger.