Medial-lateral Stability Index Research Articles

Single-Session Cerebellar Transcranial Direct Current Stimulation Improves Postural Stability and Reduces Ataxia Symptoms in Spinocerebellar Ataxia.

Spinocerebellar ataxia (SCA) results in balance and coordination impairment, and current treatments have limited efficacy. Recent evidence suggests that combining postural training with cerebellar transcranial direct current stimulation (ctDCS) can improve these symptoms. However, the combined effects of ctDCS and postural training on individuals with spinocerebellar ataxia remain underexplored. Ten volunteers with (SCA type 3) participated in a triple-blind, randomized, crossover study to receive a single session of ctDCS (2mA for 20min) and a sham ctDCS session separated by at least one week. The Biodex Balance System was used to assess balance at each session, measuring overall stability index, anteroposterior stability index, and medial-lateral stability index. As secondary outcomes, cerebellar ataxia symptoms were evaluated using the 8-item Scale for Assessment and Rating of Ataxia. The assessments were conducted before and after each session. The results indicated that ctDCS enhanced the overall stability index when compared to sham ctDCS (Z = -2.10, p = 0.03), although it did not significantly affect the anteroposterior or medial-lateral stability indices. Compared to the baseline, a single session of ctDCS reduced appendicular symptoms related to cerebellar ataxia, as evidenced by improvements in the nose-finger test (Z = -2.07, p = 0.04), fast alternating hand movements (Z = -2.15, p = 0.03), and heel-to-shin slide (Z = -1.91, p = 0.05). In conclusion, our study suggests that a single session of ctDCS, in combination with postural training, can enhance balance and alleviate ataxia symptoms in individuals with cerebellar ataxia. This study was approved by the local research ethics committee (No. 2.877.813) and registered on clinicaltrials.org (NCT04039048 - https://www.clinicaltrials.gov/study/NCT04039048 ) on 2019-07-28.

Evaluation of Balance and Muscle Strength of Upper and Lower Limbs in Rock Climbers

Abstract Introduction. The purpose of this study was to evaluate the effects of bouldering on upper and lower limb muscle strength and body balance. Material and Methods. The study group consisted of 22 climbers (aged 27.23 ± 4.81) with at least 2 years of bouldering experience, while the control group consisted of 20 men (aged 23.10 ± 5.28) not practicing rock climbing. The study received approval from the local bioethical commission in Poland. Static and dynamic stabilographic parameters were measured with eyes open (EO) and closed (EC) on the Biodex Balance System SD USA (BBS) platform. Subsequently, the maximum muscle torques of the elbow, hip, knee and ankle joints were measured in isometric conditions. Hand-grip strength (HGS) with and without the thumb was assessed using a handheld dynamometer. Results. Climbers achieved significantly higher values of HGS with the thumb of both hands (p < 0.005), foot extensors strength (FES) in both limbs (p < 0.05) and left hip extensors (HES L) (p < 0.05). They also achieved significantly lower values of all stabilographic parameters, indicating better balance compared to the control group (p < 0.05). An interaction of HES x SIDE across the groups was observed (F(1,40) = 13.588, p < 0.001 η2 = 0.254). Moreover, there was a statistically significant negative correlation of ankle extensors strength with medial-lateral stability index (MLSI EC) (right: r = -0.418; left: r = -0.331) and fall risk index (FRI6-2) (right: r = -0.520; left: r = -0.435). Conclusions. Regular climbing training develops muscle strength, especially FES, HES, HGS, and improves balance. Climbing can be used for prevention of muscle weakness and equilibrium disorders.

Comparison of postural sway in individuals with and without dynamic knee valgus

BackgroundDynamic 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.MethodsIn 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).ResultsThe 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).ConclusionThough 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.

Somatic characteristic, morphological asymmetry and postural stability of youth male canoeists compared to control. A cross-sectional study.

To determine the relationships between selected morphological characteristics and the level of body composition asymmetry with postural stability among canoeists and a control group. The sample consisted of 43 males (21 canoeists 21.8±3.29 years and 22 university students 21.7±1.32 years). Measurements included body height and weight. Segmental body composition analysis was assessed using the bioelectrical impedance by determining: fat mass (FM, kg, %), fat-free mass (FFM, kg) and predicted muscle mass (PMM, kg). Postural stability was tested using the BIODEX Balance System. Anterior-posterior stability index (APSI), medial-lateral stability index (MLSI) and overall stability index (OSI) were calculated. Our findings suggest that the canoeists had statistically lower level of fatty tissue compared to controls. There was a statistically important difference between groups in lower limb FM (% and kg). In both groups morphological asymmetry was observed, but in most cases-in athletes. Asymmetries between right and left arms appeared in all parameters, while asymmetries between right and left legs were noted in all parameters except FM (kg). There were relationships between stature and body weight with postural stability in canoeists. Canoeists demonstrated better balance than controls, particularly in the APSI. For all stability indices, significant differences were observed between right and left legs across all participants. Athletes, with larger asymmetries or poorer balance, require more attention to improve performance and reduce the risk of overload injury. Future studies needed to develop sport-specific level of morphofunctional asymmetry which would be optimal for sport results and health as well.

Knee stability training exercise versus Biodex balance training on dynamic balance indices in individuals with knee osteoarthritis: A Randomized clinical trial

Objective. To compare the impacts of Knee stability training exercise versus Biodex balance training on dynamic balance indices in individuals suffering from knee osteoarthritis. Methods. This randomized, double-blind, pre-post measurement study included forty patients aged 45 to 65 with knee osteoarthritis. They were classified into 2 groups at random: group A (n = 20), which received knee stability training plus strengthening exercise, and group B (n = 20), which received Biodex balance training plus strengthening exercise. The Biodex Balance System and Visual Analog Scale were utilized to quantify dynamic balance indices as well as pain intensity at baseline and four weeks following therapy. Results. Statistically significant differences were reported in the overall stability index (OASI), anterior-posterior stability index (APSI), medial-lateral stability indices (MLSI), and Visual Analogue Scale (VAS) values before and after treatment for group A (p < 0.05) as well as before and after treatment for group B (p < 0.05). Statistically significant differences were reported among the two groups (A & B) regarding the post-treatment values of the OASI, APSI, MLSI, and VAS (p < 0.05). Conclusion. Improvement in all dynamic balance indices and pain was reported after knee stability training exercises and after Biodex balance training, with greater improvement after Biodex balance training.

Less impact absorption at the ankle joint is related to the single-leg landing stability deficit in patients with chronic ankle instability

Single-leg landing (SLL) stability deficits are common dysfunctions after lateral ankle sprain (LAS), and are associated with reinjury and needs to be addressed. SLL stability deficits could be associated with impact absorption ability. Thus, we evaluated these relationships. We recruited 46 patients with chronic ankle instability (CAI) and 64 control patients and measured their kinematics, SLL stability, and impact absorption ability. The SLL stability was evaluated by calculating the anterior-posterior stability index (APSI) and medial–lateral stability index (MLSI). The impact absorption ability was evaluated by calculating the energy absorption (EA). The large negative value of the EA indicated the absorption of a large amount of energy. The Japanese version of identification of functional ankle instability (IdFAI-J) score (P < 0.001), MLSI value (P = 0.004), and sagittal plane ankle EA value (less EA at ankle joint) (P < 0.001) were significantly high in CAI, and sagittal plane knee EA value (more EA at knee joint) (P < 0.041) was significantly low in CAI than in the control group. Multiple regression analysis showed that the APSI was associated with sagittal plane ankle EA (β = 0.275, P = 0.004). The MLSI was associated with sagittal plane ankle EA (β = 0.204, P = 0.034) and the idFAI score (β = 0.234, P = 0.015). The SLL stability impairment after LAS was related to decreased impact absorption ability at the ankle joint.

Determination of Fall Risk Predictors from Different Groups of Variables

Abstract Introduction. Risk factors associated with falling in the elderly are numerous. Most existing tools use a combination of functional assessment and risk scoring based on known risk factors. The aim of the study was to verify which parameters could be used to predict fall risk (FR) in older women. Material and Methods. The study involved 56 inactive females aged 71.77 ± 7.43(SD). Backward stepwise regression analysis was performed to determine which independent variables predict FR in older women. Results. Significant predictors of FR were: in model 1 – age and body mass (in 32%); in model 2 – knee extensor strength of the right lower limb (KEs R) (in 20%); in model 3 – the Timed up and Go test (TUG) (in 25.5%); and in model 4 – medial-lateral stability index with eyes open (MLSI EO) (in 35%). By means of backward stepwise regression analysis using the above models, the variables that significantly influence FR in seniors were body mass, MLSI EO, KEs, and age. The above analysis shows that these indicators (model 5) may predict FR in older women in 59% of cases. Conclusions. It was determined that variables that significantly influence FR in seniors were body mass, age, KEs, and MLSI EO. Research should be continued to identify more predictors and define norms that indicate FR.

Validity of the frame subtraction method in dynamic postural stability.

BackgroundThe movement of targeted subjects can be calculated using the frame subtraction method. However, the validity of this evaluation method of dynamic postural stability has not been clarified yet. This study aimed to verify the validity of the evaluation method for jump landing using the frame subtraction score based on the ground reaction force (GRF).MethodsTwenty subjects performed single-leg jump landing, and their dynamic postural stability index (DPSI), medial‒lateral stability index (MLSI), anterior‒posterior stability index, and vertical stability index (VSI) were calculated from the GRF. Simultaneously, motion images were captured using digital video cameras in the sagittal and frontal planes. After the motion images were analyzed using the frame subtraction method, the frame subtraction scores in the frontal, sagittal, and combined planes were calculated. To confirm its validity, the relationship between the frame subtraction scores and GRF parameters was investigated using Pearson's correlation analysis.ResultsThe frame subtraction scores in the frontal and combined planes were significantly correlated with the DPSI, MLSI, and VSI (r = 0.46–0.75, P < 0.05).ConclusionsTherefore, the frame subtraction method could be applied to the evaluation of dynamic postural stability. Markerless systems are deemed useful in clinical practice.

Does Physical Activity Moderate the Relationship between Myopia and Functional Status in Children 9-11 Years of Age?

Although previous studies have reported an association between physical activity (PA) and myopia in school-aged children, little is known about the link between myopia and children’s functional status. The purpose of this study was to investigate dynamic balance control in relation to the daily PA levels of myopic schoolchildren aged 9–11 years (n = 52) versus a non-myopic control group (n = 53). A single leg stance test performed on the instability platform of the Biodex Balance System was used to assess balance control. The overall stability index (OSI), anterior-posterior stability index (APSI) and medial-lateral stability index (MLSI) were analyzed. PA levels were calculated using the World Health Organization European Childhood Obesity Surveillance Initiative family record form. Myopes and non-myopes were separated into three subgroups based on PA level (low, moderate and high). Myopia significantly affected OSI (F = 40.46, p < 0.001), APSI (F = 33.93, p < 0.001) and MLSI (F = 49.51, p < 0.001). There were significant differences (p < 0.001) between myopic and non-myopic children with low and moderate levels of PA, whilst there were no differences between compared children with high levels of PA. High PA levels had a positive impact on balance control in myopes. Our results showed that PA levels moderate the relationship between myopia and children’s functional status.

Effects of Transcranial Direct Current Stimulation over the Primary Motor Cortex in Improving Postural Stability in Healthy Young Adults.

Simple SummaryTranscranial direct current stimulation (tDCS) is used as an adjuvant rehabilitation treatment to improve postural control and lower limb function. This study explored the effects of sham and anodal tDCS over the leg region of M1 on static and dynamic postural stability in healthy young adults. Jump-landing tasks were used to examine dynamic postural stability. Static postural stability was assessed by a single-leg stand on force plates with open eyes. Anodal tDCS had an immediate improving effect on static and dynamic postural stability, and might evolve as an adjuvant rehabilitation treatment to enhance postural deficits in the future.Transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) is of increasing interest to improve motor performance in healthy adults and patients with respective deficits. This study aimed to examine whether tDCS over M1 can improve static and dynamic postural stability in young healthy adults. Seventeen healthy participants (mean age = 25.14 ± 2.50 (standard deviation, SD) years) received sham and anodal tDCS (2 mA) over the vertex at the Cz electrode position for 15 min. Static and dynamic postural stability were evaluated before and immediately after tDCS. The center of pressure (COP) sway area (COPSA) and COP maximum displacements to medio-lateral (COPML) and antero-posterior directions (COPAP) were used to evaluate static postural stability. The anterior–posterior stability index (APSI), medial–lateral stability index (MLSI), vertical stability index (VSI), dynamic postural stability index (DPSI), and time to stabilization (TTS) in forward (FL), 45° anterior lateral (LL), and 45° anterior medial (ML) direction landing, as well as the Y-balance composite score (YBTCS) were used to assess dynamic postural stability. The results showed that the LL-TTS (p = 0.044), non-dominant leg COPSA (p = 0.015), and YBTCS (p < 0.0001) were significantly improved in the real stimulation as compared with the sham stimulation session, and anodal tDCS significantly changed dominant leg COPAP (p = 0.021), FL-APSI (p < 0.0001), FL-TTS (p = 0.008), ML-TTS (p = 0.002), non-dominant leg YBTCS (p < 0.0001), and dominant leg YBTCS (p = 0.014). There were no significant differences in all obtained balance values in the sham stimulation session, except for non-dominant leg YBTCS (p = 0.049). We conclude that anodal tDCS over M1 has an immediate improving effect on static postural stability and dynamic performance in young healthy adults. This makes tDCS a promising adjuvant rehabilitation treatment to enhance postural stability deficits in the future.

Does insole hardness affect the dynamic postural stability of basketball athletes during jump landing?

This study aimed to examine the effects of shoe insole hardness on the dynamic postural stability of basketball athletes during jump landing manoeuvres. Twenty college basketball athletes were recruited to complete a single-leg jump landing task on a force plate in three insole conditions (soft-, rigid- and no-insole). Kistler force plate and Pedar-X insole system were used to collect the ground reaction force (GRF) and plantar pressure data. Dynamic Postural Stability Index (DPSI), Anterior-Posterior Stability Index (APSI), Medial-Lateral Stability Index (MLSI), and Vertical Stability Index (VSI) were then calculated from GRF data. DPSI, APSI, MLSI, and VSI were statistically conducted among the three insole conditions by a one-way ANOVA with repeated measures. MLSI were decreased when wearing soft- and rigid insoles compared with no-insole condition (p &lt; 0.05). However, there were no significant differences in APSI and VSI among the three insole conditions. In the midfoot region, contact areas were increased in the soft- and rigid insole than the no-insole condition (p &lt; 0.0001). Dynamic balance of basketball athletes in the medial-lateral direction could be enhanced by wearing insoles during jump landings tasks. However, the postural stability of basketball athletes did not increase with insole hardness increasing.

Effects of vitamin D supplementation and aerobic exercises on balance and physical performance in children with Down syndrome

Background/Aims Children with Down syndrome are prone to vitamin D deficiency. Vitamin D supplements are commonly used to treat and prevent vitamin D deficiencies. There is growing evidence that support the role of vitamin D improving muscles and central nervous system function. The aim of this study was to investigate the interaction effects of vitamin D supplementation combined with aerobic exercises and conventional physical therapy on balance and physical performance in children with Down syndrome. Methods A randomised controlled trial was conducted for 38 children with Down syndrome, with ages ranging from 8 to 12 years. They were divided randomly into two groups. The control group (n=19) received conventional physical therapy and aerobic exercises, while the study group (n=19) received conventional physical therapy, aerobic exercises and vitamin D in the form of an oral daily dose of vitamin D3 400 IU (cholecalciferol). The children in both groups participated in the same physical therapy for 45 minutes, 3 days a week for 12 weeks, and undertook 15 minutes of aerobic exercise after the physical therapy sessions. Balance was evaluated by using the Biodex Stability System and physical performance was evaluated by using the 6-Minute Walk Test. Results All groups showed a significant improvement in the medial-lateral stability index, the anterior-posterior stability index, the overall stability index and the 6-Minute Walk Test after treatment (P&lt;0.05). The study group showed a significant improvement in the measured variables compared with that of the control group (P&lt;0.05). Conclusions Vitamin D supplements, combined with aerobic exercises and conventional physical therapy, could improve balance and physical performance in children with Down syndrome. Therefore, vitamin D and aerobic exercises should be considered as an adjunctive to physical therapy.

Effect of upper extremity constraints on functional and dynamic postural control in children with hemiplegic cerebral palsy

ABSTRACT Purpose To compare the effects of upper extremity constraints on functional and dynamic postural control in children with hemiplegic cerebral palsy. Materials and Methods Twelve children with hemiplegic cerebral palsy and 12 typically developing children ages 5 to 12 years (GMFCS I–II) were evaluated with the Timed Up and Go (TUG) and Biodex Balance System during three upper extremity (UE) conditions: 1) Free UEs (no constraints), 2) Simple UE constraint (unaffected/dominant UE constrained with a sling), and 3) Difficult UE constraint (Simple constraint plus the other UE holding cup of water). Results The UE condition had significant effects on Overall Stability Index (OSI) (F(2,44) = 24.899, p < .001), Medial-Lateral Stability Index (MLSI) (F(2,44) = 4.380, p = .018), Anterior-Posterior Stability Index (F(2,44) = 6.187, p = .004), and TUG scores (F(2,44) = 113.372, p < .001). Group was significant for OSI (F(1,22) = 7.906, p = .010), MLSI (F(1,22) = 13.113, p = .002), and TUG (F(1,22) = 36.282, p < .001). Conclusions The upper extremity appears to have a role in maintaining functional balance and postural stability in children with hemiplegic cerebral palsy and should be considered during intervention programs.

안정성 및 기능적 불안정성 발목관절의 정적 균형 능력에 대한 키네시오 테이핑의 즉각적인 효과 비교 : 예비연구

The aim of this study is to find out the immediate effect of kinesio taping on static balance for stable ankles and functional instability ankles in general adults, and whether kinesio taping affects stable ankles as well as functional instability ankles. Twenty-two healthy adults were selected and divided into two groups(stable ankle group and functional instability ankle group) according to the Cumberland Ankle Instability Tool (CAIT). If the subject's CAIT score is 28 or higher, it is classified as a stable ankle, and if the CAIT score is 24 or lower, it is classified as a functional ankle instability. To determine the effectiveness of kinesio taping, the static balance ability(overall, anterior-posterior, and medial-lateral stability index) was measured by the Biodex Balance System®. As a result, there was no significant difference on the static balance between before and after application of kinesio taping in both groups. And there was no significant difference between stable ankle and functional instability ankle groups. These results indicate that kinesio taping on stable and functional instability ankles for healthy adults has no immediate effect on static balance. In future studies, it will be necessary to examine the short-term and long-term effects of kinesio taping on elderly and subjects with ankle injuries.

Effect of workshops for coaches on the motor ability of balance in children practicing sports in late childhood

BackgroundThe coach attitude impacts the whole mind and body system of a child athlete from emotional and motivational aspects to motor skills like motor coordination. It translates into the ability to control and stabilize posture. The vestibular system plays an important role in this regulation. This system, next to the visual system and mechanoreceptors, is responsible for balance and control during posture transition. Moreover, the vestibular system is influenced by emotional factors. Therefore the authors of this study focused on the changes in the balance stability of children practicing sport after the implementation of the psychological workshops for coaches.MethodsFifty-nine children at the age of 9–12 practicing soccer, art gymnastic and sport gymnastic were divided into two groups. The experimental group consisted of 31 participants and 28 in the control group. Experimental group children were under the influence of the 3 coaches who attended three workshops over 12 weeks period. Control group children were coached by 5 coaches who attended no workshops. Postural stability tests were performed on children before and after the workshops.ResultsThe statistically significant changes were observed in selected parameters of children’s balance stability after the experiment. The significant difference between the experimental and control group in Overall Stability Index (OSI) (p < 0.0002), Anterior–Posterior Stability Index (AP) (p < 0.01), Medial–Lateral Stability Index (ML) (p < 0.01) with eyes open were observed after the experiment. The results show a significant deterioration in control group contrary to the experimental group where the improvement trend was observed. Moreover, the difference between the groups was observed in OSI parameter (p < 0.005) with eyes closed after the experiment.ConclusionThe results obtained by the authors of the current study may support the thesis that educating coaches allows for better results in postural stability of child’s athletes. Nevertheless, this thesis requires further research, with particular emphasis on the age and gender of young athletes.

Do Athletes With a Reconstructed Anterior Cruciate Ligament Respond Differently Than Controls to Visual Challenges When Dynamic Postural Stability is Assessed?

Individuals returning to sport after anterior cruciate ligament reconstruction (ACLR) are at an increased risk of sustaining a subsequent ACL injury. It is suspected that increased reliance on visual information to maintain stability may factor into this increased risk. The connection between visual reliance and ACLR is not well understood during dynamic tasks. Examination of the proposed visual reliance may help improve returning to sport standards and reduce subsequent ACL injury risk. A total of 12 ACLR individuals and 12 age- and sex-matched controls completed several trials of a normalized dynamic hop task on both limbs under 3 different visual conditions (eyes open, low visual disruption, and high visual disruption). Stroboscopic eyewear were worn by each participant to disrupt vision during testing. Ground reaction force data were collected during landing. Dynamic postural stability was assessed using 2 separate calculations: dynamic postural stability index and time to stability. No significant statistical interactions or group differences were observed. The stroboscopic eyewear did increase the medial-lateral stability index from the eyes open to the low visual disruption condition (P < .05). These findings suggest that ACLR individuals do not rely on visual information more than controls during a dynamic hop task.

The effects of visual cognitive tasks on landing stability and lower extremity injury risk in high-level soccer players

BackgroundVisual cognition plays a pivotal role in sports. It is widely recognized that there is an intriguing coupling that they could affect each other through interaction between visual cognition and motor control, but few studies linked the effects of visual cognitive tasks on landing stability to postural control and injury risk. Research questionWhether visual cognitive tasks affect the landing stability and lower limb injury risk of professional soccer players? MethodsThe current study used a three-dimensional Multiple Object Tracking (MOT) task to simulate visual cognitive difficulties experienced in soccer matches. Fifteen male high-level soccer athletes (height: 181.43 ± 7.36 cm, weight: 75.37 ± 10.67 kg, training years: 10.07 ± 2.98 yr) from our school team were recruited and completed a landing action from a high platform with and without MOT tasks. Vicon infrared high-speed motion capture system and three-dimensional force measuring platform were used to collect various outcomes simultaneously. ResultsThe Time to Stabilization (TTS) during landing was significantly prolonged, while the Medial-Lateral Stability Index (MLSI), Anterior-Posterior Stability (APSI), Dynamic Postural Index Stability Index (DPSI), the trajectory lengths, and envelope area of COP during landing were also increased during MOT dual-task. DiscussionThe decline of these indicators reflected the deterioration in postural stability and greater requirements for maintaining balance which could increase the risk of injury in soccer athletes. We advocate that adequate visual attention and visual information processing might play critical roles in maintaining dynamic balance through the supraspinal neural network.

The immediate effect of a single whole-body vibration session on balance, skin sensation, and pain in patients with type 2 diabetic neuropathy.

Patients with diabetic neuropathy usually suffer from impaired balance, pain, and decreased sole-foot sensation. The present research was designed to appraise the relic of whole-body vibration (WBV) on balance, pain, and sole-foot sensation in diabetic neuropathy patients. Present study was a single-blind randomized controlled clinical trial. Thirty-four patients with type 2 diabetic neuropathy were randomly divided into intervention groups (n=17) and control (n=17). The therapeutic program in the intervention group included standing on the platform of the WBV device, and in the control group included using the device in off mode. Dynamic balance (including overall, anterior-posterior, and medial-lateral stability indices) was measured using Biodex device, functional balance with timed up and go (TUG) test, pain using the visual analog scale (VAS), and sole-foot sensation of both feet with a monofilament. The outcomes were measured in both groups before and after the interventions. Sixteen people in each group were analyzed. Intra-group comparison showed a significant improvement in the mean pain (P = 0.000), functional balance (P = 0.011), right and left sole-foot sensation (P = 0.001), and overall (P = 0.000), anterior-posterior (P = 0.000) and medial-lateral (P = 0.000) stability indices for the intervention group in post-intervention compared to pre-intervention. However, changes in the control group were not statistically significant. Results of inter-group comparison indicated a significant improvement in all parameters in the intervention group, except for functional balance. WBV can be effective in reducing pain and improving the sole-foot sensation and dynamic balance.

The Influence of Pronated Foot Posture on Knee Isokinetic Strength, Static and Dynamic Postural Stability in Healthy Young Individuals

Background: The foot is a complex body structure that plays an important role in static and dynamic situations. Previous studies have reported that altered foot posture might affect knee joint strength and postural stability, however their relationship still remains unclear. Objects: The purpose of this study was to identify whether pronated foot posture has an influence on knee isokinetic strength and static and dynamic postural stability. Methods: Forty healthy young males aged 18 to 26 years were included. Foot posture was evaluated using the Foot Posture Index-6 (FPI-6), and the subjects were divided into two groups according to their FPI-6 scores: a neutral foot group (n = 20, FPI-6 score 0 to +5) and a pronated foot group (n = 20, FPI-6 score +6 or more). Biodex Systems 3 isokinetic dynamometer was used to evaluate knee isokinetic strength and hamstring to quadriceps ratio at three angular velocities: 60°/sec, 90°/sec, and 180°/sec. The static and dynamic postural stability in a single-leg stance under the eyes-open and eyes-closed conditions were measured with a Biodex Balance System. Results: There were no significant differences between the groups in knee isokinetic strength and static postural stability (p > 0.05), but there was a significant difference in the medial– lateral stability index (MLSI) for dynamic postural stability under the eyes-closed condition (p = 0.022). The FPI-6 scores correlated significantly only with the dynamic overall stability index (OSI) and the MLSI (OSI: R = 0.344, p = 0.030; MLSI: R = 0.409, p = 0.009) under the eyesclosed condition. Conclusion: Participants with pronated foot had poorer medial–lateral dynamic stability under an eyes-closed condition than those without, and FPI-6 scores were moderately positively correlated with dynamic OSI and dynamic MLSI under the eyes-closed condition. These results suggest that pronated foot posture could induce a change in postural stability, but not in knee isokinetic strength.

Investigation of balance performance under different sensory and dual-task conditions in patients with chronic neck pain

BackgroundMost studies suggest that people with chronic neck pain (CNP) have decreased balance abilities. However, balance performance during performing concurrent tasks is not clarified. ObjectivesTo investigate balance performance under different sensory and dual-task conditions in people with and without CNP. MethodTwenty-two women with CNP and twenty-two asymptomatic women were tested using the Biodex Stability System. Overall stability index (OSI), anterior/posterior stability index (APSI), medial/lateral stability index (MLSI) were obtained in two sessions: eyes-open and eyes-closed. Both sessions consisted of four conditions: quiet standing, rotating head, counting backward, standing on foam. Higher index scores mean poorer balance. DesignCase-Control study. ResultsA mixed factorial ANOVA (2 × 8 design) showed that there was a main effect of CNP on OSI, APSI, and MLSI (p < 0.001), which indicates that CNP causes poor balance. Further, there was an interaction between CNP and test conditions for only OSI (p < 0.05). Simple effects tests showed that patients with CNP had higher OSI in all conditions except standing on foam with eyes-open, and quiet standing and counting backward with eyes-closed (p < 0.05). The largest effect size was obtained during rotating head with eyes-open (η2:0.301), followed by counting backward with eyes-open and quiet standing with eyes-open (η2:0.267 and 0.245). Performing a concurrent task, closing eyes, or standing on foam mostly increased OSI in both groups (p < 0.05). ConclusionsPatients with CNP have poorer balance under different sensory and dual-task conditions. Addressing balance assessment while performing concurrent tasks, especially head rotations, may offer new insights into the management of CNP.