Stephan Becker

Background: Sensorimotor foot orthoses (SMFOs) regulate muscle tone. Within this growing body of evidence, the impact of two SMFO elements, the retrocapital pad and toe bar, on the plantar flexors has not yet been investigated. It has been observed and postulated that combining these two elements may reduce calf muscle activity. Material and methods: This randomized crossover study included 29 healthy participants (age, 25.8 ± 6.5 years). Each participant performed 30-seconds walking and running trials on a treadmill to compare the SMFOs and no-foot orthoses (NFOs) conditions. The activities of the gastrocnemius medialis and lateralis were measured using surface electromyography (sEMG). Statistical parametric mapping (SPM) was calculated and analyzed using a paired t-test-like statistic (significance level, α = 0.05). Results: No significant differences in muscle activity were observed between the SMFOs and NFOs conditions during either walking or running in healthy adults. Conclusion: The effects of SMFOs observed in clinical practice may not appear to extend to healthy young adults.

Background/Objectives: Pes planovalgus is one of the most common misalignments in children. In this study the established biomechanical foot orthoses (BMFO) are being compared with a more recent treatment: sensorimotor foot orthoses (SMFO). SMFO are a more recent treatment and aim to correct malalignment by specifically modulating muscle activity rather than relying solely on passive mechanical support, as is the case with BMFO. Methods: Thirty-two children and adolescents aged six to six-teen participated in this study. After randomized group allocation, the rearfoot angle was analyzed by two-dimensional gait analysis in the SMFO-group (n=18) and the BMFO group (n=14) under three conditions: without foot orthoses (baseline), with foot orthoses (immediate) and after four weeks of use. Results: (1) SMFO and BMFO significantly improved the rearfoot angle immediately after application, (2) the achieved correction was maintained over four weeks in both groups, and (3) despite baseline differences, the superior rate of improvement in the SMFO-group resulted in comparable rearfoot alignment between SMFO and BMFO at the four-week follow-up. Conclusions: Based on the results, it can be concluded that SMFO and BMFO are comparable methods for treating pes planovalgus in children and adolescents.

Background: Sensorimotor foot orthoses (SMFO) may be a helpful intervention to improve balance by enhancing proprioceptive input within the sensorimotor control loop. SMFO intervention could have beneficial effects on reducing risk of ankle sprains and falls.Methods: A total of 57 healthy adults (age: 48.5 ± 11.8 years) completed a static balance test (30 s) on a force plate, with open eyes (OE) and closed eyes (CE). Balance performance was assessed by using posturography to measure the sway area (mm²), under SMFO and no foot orthoses (NFO) conditions.Results: Descriptive statistics show a reduced median of 1.9 cm² (29.6%) for SMFO with CE. No interaction was found, while main effects showed significant differences (vision: p < 0.001, sole: p = 0.004). post-hoc tests underlined these results and static balance improved by a median 0.8 cm² (14.5%) with SMFO compared to NFO.Conclusion: The SMFO seems to support static balance and sensorimotor system, which could help to avoid falls and injuries as ankle sprains. Further age groups, long-term effects and the impact on dynamic balance must be studied.

Background: Preventive team testing showed an above-average number of pes cavus among soccer players. This raised the question of whether wearing relatively small soccer shoes - as it is often the case for soccer players - shoes might be responsible and cause a kind of foot compression and a muscular-induced pes cavus. Methods: This cross-sectional study included 198 male youth and adult soccer players (age: 18.6±5.8 years, height: 176.3±14.8 cm, body mass: 69.9±11.5 kg). The delta between shoe and foot length was compared with arch index (AI) and normalised truncated navicular height (NTNH) and especially for those whose shoes were too small. Results: The data confirms that among soccer players, 34% had a pes cavus, only 15% were free of pes planus or pes cavus and 27% wore shoes that were too small. Contrary to the authors hypothesis, the NTNH revealed a general relationship with the delta between foot length and shoe length. Players with shoes that were too small had a significantly higher arch (AI = 0.24) than players with adequate shoe size (AI = 0.25), but on average, the arch was still in the range of a normal foot. No correlation was found between the magnitude of the delta and the AI value for the subgroup of players whose shoes that were too small. Conclusions: The data confirm the increased prevalence of pes cavus among soccer players, but could not confirm the authors’ hypothesis that this may be caused by wearing shoes that are too small.

This study explores the complex dynamics of rank-order stability by analyzing the current-to-final rank difference (CFRD), a metric that provides a dynamic view of rank fluctuations and their impact on the final ranking. This approach enables the identification of critical event phases that significantly influence the final rank. Specifically, we examine how varying team sizes and performance levels shape temporal trends in CFRD during 24-hour cycling races. A comprehensive dataset covering four consecutive years (2019-2022) of a 24-hour cycling race on a 17.9 km repetitive driven road track, encompassing diverse team sizes (solo rider, or teams of 4 and 10), is used. The results indicate significant interactions between time, team size, and performance F(18.04) = 1.74; p = 0.03). As the race progresses, the final standings become progressively more predictable. Solo riders exhibit the least clarity in their final standing throughout the race. In contrast, larger teams achieve a clearer indication of their final ranking earlier in the race. Medium-performance teams, especially solo riders, show lower clarity in their final standing across the race duration, whereas high- and low-performance teams tend to exhibit more predictable outcomes at earlier stages of the race. Overall, this study advances our understanding of endurance team cycling, and offers valuable insights for strategic decision-making and race optimization.

Background: Measuring postural sway and comparing results in a pre-post design or with reference values can increase diagnostic accuracy and the quality of certain treatments and rehabilitation. The process of continuously regulating and sustaining a stable posture involves intricate sensorimotor control. Methods: All 173 participants (78♂, 95♀; 21.9 ± 2.7 years, 172.6 ± 9.8 cm; 70.0 ± 13.3 kg; BMI: 22.7 ± 2.8) were students in sport and health sciences. Static posturography (open eyes, closed eyes) was performed for 30 s under standardized conditions on a force plate and the parameters analyzed were the sway path length (SPL) and the area of ellipse (AoE). Results: On average, with eyes open the SPL was 250 ± 116 mm, and the AoE was 125 ± 82 mm² measured with eyes open. With eyes closed, the SPL increased to 337 ± 151 mm and the AoE increased to 175 ± 125 mm². An examination of possible sex differences in static balance revealed only a significant difference for the AoE with closed eyes. In general women achieved slightly better scores than men did. Body height did not have an influence on balance. Conclusion: The present dataset provides reference values for young and sportive adults between 18 and 30 years of age. An examination of possible gender differences in static balance revealed a significant difference only between men and women for AoE with closed eyes. Body height does not have an influence on balance but the literature is inconsistent and further research is needed. Owing to the popular use of posturography in practice, further reference values are needed, and more attention should be given to ΔSPL and ΔAoE (open eyes, closed eyes) as well as the interpretation of the relationship between the SPL and AoE.

Background: Patellofemoral pain (PFP) significantly affects patients’ daily activities and consequently reduces their quality of life. Custom-made foot orthoses (FOs) are a common method of medical treatment that positively influences biomechanical factors such as the kinematics of the lower extremity and reduces pain perception in patients. However, there is a gap in research regarding the influence of different FO treatments on knee pain. Therefore, this study addresses the impact of biomechanical foot orthoses (BMFOs) and sensorimotor foot orthoses (SMFOs) on patients with foot deformity and PFP. Methods: A total of 26 participants (9 men, 17 women; 27.7 ± 10.7 years; 175.0 ± 0.1 cm; 75.7 ± 18.8 kg; BMI: 24.7 ± 5.6) took part in this randomized controlled clinical trial. In the pre-test, knee pain was evaluated using the Kujala Anterior Knee Pain Scale after the physician’s anamnesis and plantar pressure measurement. A 3-month intervention with SMFO and BMFO was performed, and weekly development was evaluated using 11-item visual analog scales (VASs). Repeated measures analyses of variance were used to assess differences between time of measurements (ToMs) and the interaction effect between ToMs and treatment groups (SMFO, BMFO). Results: Statistical analysis revealed no statistically significant interaction between ToMs and treatment groups but a significant main effect on Kujala anterior knee pain scores (M_Diff = 10.189; p = 0.014) and 12-week VAS (p = 0.001). Conclusions: The findings indicate that both treatment approaches effectively alleviated perceived knee pain in the PFP sample with foot deformity, with neither approach demonstrating superior efficacy. This trial was registered in the WHO International Clinical Trials Registry Platform (ICTRP) and German Clinical Trials Register (DRKS00035082).

Patellofemoral pain (PFP) significantly affects patients’ daily activities and consequently reduces their quality of life. Custom-made foot orthoses (FO) are a common method of medical treatment that positively influence biomechanical factors such as the kinematics of the lower extremity and reduce pain perception in patients. However, there is a gap in the research regarding the influence of different FO treatments on knee pain. Therefore, this study addresses the impact of biomechanical foot orthoses (BMFO) and sensorimotor foot orthoses (SMFO) on patients with foot deformity and PFP. A total of 26 participants (9 men, 17 women; 27.7 ± 10.7 years; 175.0 ± 0.1 cm; 75.7 ± 18.8 kg; BMI: 24.7 ± 5.6) took part in this randomized-controlled clinical trial. In the pre-test, knee pain was evaluated using the Kujala anterior knee pain scale after the physician’s anamnesis and plantar pressure measurement. A 3-month intervention with SMFO and BMFO was performed, and weekly development was evaluated using 11-item visual analog scales (VASs). Repeated measures analyses of variance were used to assess differences between time of measurements (ToMs) and the interaction effect between ToMs and treatment groups (SMFO, BMFO). Statistical analysis revealed no statistically significant interaction between ToMs and treatment groups but a significant main effect on Kujala anterior knee pain scores (MDiff = 10.189; p = .014) and 12-week VAS (p = .001). The findings indicate that both treatment approaches effectively alleviate perceived knee pain in the PFP sample with foot deformity, with neither approach demonstrating superior efficacy. This trial was retrospectively registered in the WHO International Clinical Trials Registry Platform (ICTRP) and German Clinical Trials Register (DRKS00035082).

Background: Individuals may exhibit altered foot pronation during gait when fatigue sets in. Therefore, a more evidence-based understanding of these fatigue-induced changes may be helpful for future gait analysis and return-to-play tests since fatigue can provide new insights that might explain a person’s complaints. Methods: A total of 25 healthy individuals (12♂, 13♀; 24.3 ± 2.7 years; 174.9 ± 9.09 cm; 70 ± 14.2 kg; BMI: 22.7 ± 2.8) participated in this controlled non-randomized study of unilateral fatigue of the right foot’s stabilizing muscles with regard to the pronation of the foot, measured by navicular drop (ND) in static (statND; standing) and dynamic (dynND; walking) states. The left foot served as the control. Surface electromyography was used to verify fatigue. Results: While the statND did not change, the dynND increased significantly by 1.44 ± 2.1 mm (=22.3%) after the foot-stabilizing muscles experienced fatigue. No correlation was found between the statND and dynND. Conclusions: Muscular fatigue can affect foot pronation. The dynND appears to be more representative of the loads in everyday life, whereby most studies use the statND.

Individuals may exhibit altered foot mechanics, in this case foot pronation, only when fatigue sets in. Therefore, a more evidence-based understanding of these fatigue-induced changes may be helpful for future gait analysis and return to play tests, since fatigue could provide new insights that might explain a person’s complaints. Methods: 25 healthy test persons (24.3±2.7 years, BMI: 22.7±2.8) participated in this controlled non-randomized study of unilateral fatigue of the right foot stabilizing muscles with regard to the pronation of the foot, measured by navicular drop (ND) in a static (statND) und dynamic (dynND) state. The left foot served as a control. Surface electromyography was used to verify fatigue. Results: While statND didn’t change, the dynND increased significantly by 1.44±2.1 mm (= 22.3 %) after fatigue of the foot stabilizing muscles. No correlation was found between statND and dynND. Conclusion: Muscular fatigue can affect foot pronation. The dynND appears to be more representative of the loads in everyday life, whereby most studies work with the statND.