Background: Fatigue is the most disabling ‎symptom for individuals with multiple ‎sclerosis which can significantly affect postural control by impairing the ability of the central nervous system to modulate sensory inputs and coordinate motor responses. This systematic review aimed to accumulate the existing evidence. This systematic review aimed to investigate the effect of ‎fatigue on postural control in individuals with multiple ‎sclerosis.‎ Methods: This systematic review was performed in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement and registered in PROSPERO with ID CRD42022376262‎. Web of Science, PubMed, Scopus, and Google Scholar was systematically searched until January 2023, and a manual search was performed using the reference lists of included studies. Two authors independently selected the studies, extracted data, and evaluated their ‎methodological quality using the Downs and Black checklist. The process was later discussed ‎with a third author.‎ Results: Five studies were included in this review, of which consistent evidence investigating a direct ‎relationship between fatigue and ‎postural control in individuals with multiple ‎sclerosis. All the studies reported negative effects on postural control. Four ‎studies executed walking tests as fatigue protocols, and one study used a strength testing protocol for both legs, which served as a fatigue-inducing activity‎. Conclusions: The available evidence suggests that individuals with multiple ‎sclerosis may experience postural control deficits due to fatigue. However, the present body of literature exhibits limitations in terms of its quality and methodology. Gender differences, balance, fatigue task, and muscle function are important factors that need to be taken into account when investigating the relationship between fatigue and postural control deficits in MS. Further high-quality research is necessary to comprehend the complex interplay between MS-related fatigue and postural control deficits after physical activity.

Background: Dynamic knee valgus (DKV) is a multi-planar faulty movement pattern that can cause faulty postural control. This study aimed to compare individuals with and without DKV aged 18–30 years old in terms of postural sway (PS). Methods: Based on the inclusion and exclusion criteria, 62 individuals with (33) and without (29) DKV were selected and assigned to two groups by conducting the single-leg squat test in the screening stage. The Biodex balance system was then employed to compare the two groups in PS. Mann–Whitney U test was conducted to compare the groups in PS. The statistical significance was set at an alpha of p ≤ 0.05. Results: The result showed that there were no significant differences between individuals with and without DKV in terms of the anterior-posterior, medial-lateral, and overall stability indices (p > 0.05). Conclusion: Apparently, there are no significant differences between individuals with and without DKV in PS due to several possible factors including differences in the measurement tools for postural control, the sensitivity of variables in the postural stability test, and the movement variability and postural stability test (single-leg stance versus double-leg stance). Therefore, it is suggested that future studies should analyze PS in more functional tasks by changing the methodological patterns.

Introduction:Cognitive limitations in Down syndrome affect learning. Furthermore, improper performance of movement and low muscle tone are among the crucial causes of pos tural control impairment and gait ins tability in Down syndrome. This s tudy was aimed to inves tigate the role of secondary cognitive tasks on time of the s tance phase of subjects with Down Syndrome. Materials and Methods: 20 males with Down syndrome with a mean age of 11.50 ± 2.28 years were selected from the patients regis tered by the Down Syndrome Association in Rasht, Anzali, and Lahijan, Gilan Province, Iran. Participants performed two different cognitive tasks while walking on the Foot Medisense machine and the timing of the s tance-phase was measured. Results: The results showed no significant difference between the intra-group factors in the right and left heel s trike phase. However, the foot flat phase, mid-s tance phase, heel-off, and toe-off phase in the right and left heel s trike phase have shown significant differences. Furthermore, a significant difference between intra-group factors for the left and right leg was observed. Conclusion: Our data indicate that the evaluation of the s tance-phase could be used for the assessment of motor function in children with Down syndrome.

Background Dynamic knee valgus (DKV) is a multi-planar faulty movement pattern that can cause faulty postural control. The primary objective of this study is to investigate the differences in postural sway (PS) between individuals aged 18–30 years old diagnosed with and without DKV. Methods In this cross-sectional study, 62 students (39 males and 23 females) with and without DKV (age: 24.58 ± 2.63 years) were selected and assigned to two groups by conducting the single-leg squat test in the screening stage. The Biodex balance system was then employed to compare the two groups in PS. Mann–Whitney U test was conducted to compare the groups in PS (p ≤ 0.05). Results The study’s findings indicate that individuals with DKV did not exhibit any significant differences, compared to those without, about the anterior-posterior stability index (with p values for both static and dynamic situations at 0.309 and 0.198, respectively), medial-lateral stability index (with p values for both static and dynamic situations at 0.883 and 0.500, respectively), and overall stability index (with p values for both static and dynamic situations at 0.277 and 0.086, respectively). Conclusion Though several possible factors could contribute to the lack of significant differences in postural sway between individuals with and without DKV, such as measurement tool differences, variable sensitivity in postural stability tests, and differences in movement variability and test stance, we recommend analyzing postural sway in more functional tasks and with different methodological patterns in future studies. Such research could help develop targeted interventions for individuals with DKV and offer a better understanding of the relationship between postural control and DKV.