Background. The Biodex Biosway® Balance System and SWAY Balance® Mobile smartphone application (SBMA) are portable instruments that assess balance function with force plate and accelerometer technology, respectively. The validity of these indirect clinical measures of postural sway merits investigation. Purpose. The purpose of this study was to investigate the concurrent validity of standing postural sway measurements by using the portable Biosway and SBMA systems with kinematic measurements of the whole body Center of Mass (COM) derived from a gold-standard reference, a motion capture system. Study Design. Cross-sectional; repeated measures. Methods. Forty healthy young adults (21 female, 19 male) participated in this study. Participants performed 10 standing balance tasks that included combinations of standing on one or two legs, with eyes open or closed, on a firm surface or foam surface and voluntary rhythmic sway. Postural sway was measured simultaneously from SBMA, Biosway, and the motion capture system. The linear relationships between the measurements were analyzed. Results. Significant correlations were found between Biosway and COM velocity for both progressively challenging single and double leg stances (τ_b = 0.3 to 0.5, p<0.01 to <0.0001). SBMA scores and COM velocity were significantly correlated only for single leg stances (τ_b = −0.5 to −0.6, p<0.0001). SBMA scores had near-maximal values with zero to near-zero variance in double leg stances, indicating a ceiling effect. Conclusion. The force plate-based Biodex Biosway is valid for assessing standing postural sway for a wide range of test conditions and challenges to standing balance, whereas an accelerometer-based SWAY Balance smartphone application is valid for assessing postural sway in progressively challenging single leg stance but is not sensitive enough to detect lower-magnitude postural sway changes in progressively challenging double leg stances.

The purpose of this study was to identify and differentiate the motor strategies associated with sensory reweighting adapted during specific sensory integration tasks by healthy young adults. Thirty-six subjects (age range: 21-33 years) performed standing computerized dynamic posturography balance tasks across progressively increasing amplitudes of visual (VIS), somatosensory (SOM) and both (VIS+SOM) systems perturbation conditions. Adaptation in the motor strategy was measured as changes in electromyographic (EMG) activities and joint angles. The contribution of the perturbed sensory input in maintaining postural stability was calculated to determine the sensory reweighting. A multivariate design was used to model a linear combination of motor adaptation variables that discriminates specific sensory integration tasks. Results showed a significant progressive decrease in postural sway per unit amplitude of sensory perturbation in each condition, indicating dynamic sensory reweighting. Linear discriminant function analysis indicated that the adaptation in motor strategy during the VIS condition was associated with increased activity of EMG and joint angles in the upper body compared to the lower body. Conversely, during the SOM and VIS+SOM conditions, the adaptation in motor strategy was associated with decreased activity of EMG and joint angles in the lower body compared to the upper body. Therefore, the adaptation in motor strategies associated with sensory reweighting were different for different sensory integration tasks.

Background/Objectives: The purpose of this umbrella review was to assess the risk of bias and the methodological and reporting quality of systematic reviews that evaluated the effects of thoracic spine manipulation (TSM) on individuals with mechanical neck pain. Methods: To be included, publications needed to be systematic reviews including studies with participants with neck pain >18 years old; at least two groups where the experimental intervention was TSM; assessed pain and/or function; and were published in English. Reviews limited to narrative, scoping, or retrospective studies, or those with cervical radiculopathy, were excluded. An electronic search was conducted in May 2025 using PubMed, CINAHL (EBSCO Host), and the Cochrane Library to identify relevant articles from inception to May 2025. Quality and risk of bias were assessed using A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2), Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020), and Risk of Bias in Systematic Reviews (ROBIS). Findings were summarized narratively and graphically. Results: Seven reviews (27 unique studies; 1394 participants, aged 18–62 years) met the inclusion criteria. Some evidence supported TSM for short-term improvement in neck pain, but confidence in results was low to critically low based on the AMSTAR 2 results. Four reviews had a high overall risk of bias, and three had a low risk. Reporting compliance varied widely (0–100%). Conclusions: While all the included systematic reviews suggested that TSM is a viable short-term option for individuals with neck pain, the overall confidence in these results ranged from low to critically low, making it difficult to draw firm conclusions about the true benefit of TSM in clinical practice. Registered prospectively in PROSPERO (CRD420251034330).