Sway Index Research Articles

Long-term effects of mild and moderate COVID-19 on static and dynamic balance

IntroductionCOVID-19 affects both musculoskeletal and central nervous systems. However, there is no research on its impact on balance in mild to moderate cases. This study aims to compare static and dynamic balance, as well as fall risk, between individuals with mild to moderate COVID-19 and those without the disease.Methods: in this case control study 30 subjects (25–45 years old) with mild to moderate severity of covid-19 and 30 healthy subjects were compared. Outcome measures of Timed Up & Go, Timed Unipedal Stance Test and the overall sway & stability index via Biodex balance device were used to evaluate static and dynamic balance and risk of fall. ResultsSignificant differences between groups were observed in most Biodex indexes: Modified Clinical Test of Sensory Interaction and Balance (mCTSIB): modes 1, 3, and 4 (p ≤ 0.001). Fall Risk Test (FRT): with eyes open/closed, on normal/narrow surfaces (p < 0.05). Unipedal Stance Test (UPST): with eyes open (p = 0.023) and closed (p = 0.00). DiscussionAll indicators of balance and fall risk were different in covid-19 patients than healthy people except the mCTSIB test mode 2 (p = 0.11) and TUG test (p = 0.33). In simple activities, balance disorder due to Covid-19 is not evident, but in more detailed tests, it is effective even with moderate and mild severity. ConclusionEven after 3–6 months of the recovery, there were significant differences in overall sway & stability index between people with covid-19 and healthy subjects.

Analysis of posture and balance impairments in individuals with chronic nonspecific neck pain-an observational study.

Neck pain is one of the most burdensome chronic musculoskeletal problems globally. Impaired proprioception is associated with Chronic Nonspecific neck pain as the structures of the cervical spine are crucial for proprioception and balance. There is a paucity of literature examining objective measures of balance and postural sway in patients with Nonspecific neck pain. This study was observational and consisted of 126 samples (63 cases and 63 controls who were recruited using convenience sampling. The demographics of the samples were collected and the postural and balance impairment was assessed using Biodex Balance SD. Mean, Median, and SD were obtained and the inferential analysis was done using the Whitney U Test and the level of significance was accepted at p < 0.05. The subjects with neck pain showed had a lower static stability index, static sway index, static stability index- forward backward and static sway index lateral scores than the normal counterparts. There are significant differences in the overall static stability index, (p < 0.001). There was a significant difference in static sway index(p = 0.003), and static stability index lateral (p = 0.004). There was no significant difference for static sway index forward and backward (p = 0.550) and lateral sway index (p = 0.711). Subjects with neck pain showed had a lower static stability index, static sway index, static stability index- forward backward and static sway index lateral scores than the normal counterparts and there was a significant difference between the static sway and static stability index in forward and backward directions as well as in lateral direction. These findings may help to assess the specific balance parameters and address the underlying causes of balance issues in patients with neck pain and also provide a comprehensive care to the patients. The trial was registered with CTRI India with registration number: CTRI/2022/07/044222.

IMPAIRED GAIT AND BALANCE DISORDERS AS RISK MARKERS FOR FALLS IN CHRONIC CEREBRAL ISCHEMIA

The main clinical syndromes of chronic cerebral ischemia (CCI) are impaired gait and balance disorders, which increase risks for falls. The objective of the study is to analyze correlation between impaired gait and postural instability to determine risk markers for falls in CCI patients. Materials and Methods. We examined 104 CCI patients (15 men and 89 women, median age 70 (63; 76) years). The patients did not have significant functional limitations in daily life (modified Rankin scale, 0–2 points). Thirteen patients (13 %) had a history of acute cerebrovascular accidents, thirty-seven patients (36 %) had a history of falls. Moderate cognitive impairment was detected in 53 patients (51 %). Impaired gait and balance disorders were assessed according to Tinetti test, Berg balance scale, and stabilometric platform. Statistica 13.0, SPSS 22 was used for statistical data processing. Results. According to the Tinetti test, impaired gait was detected in 101 patients (97 %), balance disorders were found in 32 patients (31 %). According to the Berg balance scale, most patients had a low risk for falls. Stabilometry showed a decrease in the limits of stability, mainly forward. Discriminant analysis revealed that significant predictors of falls in CCI patients are the “forward” limit of stability (&lt;59 points), female gender, age (&gt;67 y.o.), depression (&gt;9 points, HADS), sway index (eyes closed) in the clinical test for sensory integration and balance (&gt;0.855), balance score for the Tinetti test (&lt;15 points), and a history of acute cerebrovascular accident. Conclusion. Stabilometry along with clinical assessment can improve the effectiveness of determining the risk group for falls in CCI patients.

Effects of rTMS to primary motor cortex and cerebellum on balance control in healthy adults.

Both the primary motor cortex (M1) and the cerebellum are crucial for postural stability and deemed as potential targets for non-invasive brain stimulation (NIBS) to enhance balance performance. However, the optimal target remains unknown. The purpose of this study was to compare the role of M1 and the cerebellum in modulating balance performance in young healthy adults using facilitatory 5Hz repetitive transcranial magnetic stimulation (rTMS). Twenty-one healthy young adults (mean age = 27.95 ±1.15 years) received a single session of 5Hz rTMS on M1 and the cerebellum in a cross-over order with a 7-day washout period between the two sessions. Three balance assessments were performed on the Biodex Balance system SD: Limits of Stability (LOS), modified Clinical Test of Sensory Interaction on Balance (mCTSIB), and Balance Error Scoring System (BESS). No significant effect of rTMS was found on the LOS. The effect of rTMS on the mCTSIB was mediated by stimulation target, proprioception, and vision (p = .003, ηp 2 = 0.37). Cerebellar rTMS improved the mCTSIB sway index under eyes closed-foam surface condition (p = .02), whereas M1 rTMS did not result in improvement on the mCTSIB. The effect of rTMS on the BESS was mediated by stimulation target, posture, and proprioception (p = .049, ηp 2 = 0.14). Cerebellar rTMS enhanced reactive balance performance during most sensory deprived conditions.

Sex Differences and Association Between Modified Balance Error Scoring System Error and Sway Index Scores in Collegiate, Club Sport, and High School Athletes

The Modified Balance Error Scoring System (mBESS) remains the standard balance tool for evaluating sport-related concussion. Discrepancies between error and objective sway scoring remain a topic of assessment measures. The purpose was to examine sex differences between error and sway index scores and association between scores on the mBESS in collegiate and high school athletes. 119 athletes completed the mBESS on a Biodex BioSway. Measures consisted of mBESS errors and sway index scores produced by the BioSway. No sex differences were observed on mBESS errors and sway index scores by competition level and the overall sample. Moderate associations were observed between error and sway index scoring for single and tandem stances.

Adding Neurofeedback Training to Neuromuscular Training for Rehabilitation of Chronic Ankle Instability: A 3-Arm Randomized Controlled Trial.

Neurofeedback training (NFT) can aid in the treatment of the abnormal patterns of the brain brought on by physical injury, enhancing cognitive and behavioral abilities. The present study aimed to compare the effectiveness of combining neuromuscular training (NMT) and NFT (NMT+NFT) with NMT alone in rehabilitating athletes with chronic ankle instability (CAI). NMT+NFT will be more effective than NMT alone. A 3-arm, single-blind randomized controlled trial. Level 2. A total number of 62 athletes, aged 18 to 25 years, with CAI, participated in this study. The study subjects were allocated randomly to 3 groups: 21 cases in the control group, 21 cases in the combination group (CG) receiving NMT+NFT, and 20 cases in the neuromuscular group (NG) practicing NMT alone, undergoing exercises related to their groups for 8 weeks. Data were recorded and analyzed before and after the 8-week training program. The primary outcome measures were postural sway indices; secondary outcomes included ankle proprioception and biopsychosocial indices. NMT+NFT was more effective than NMT alone in terms of improving postural control during single- and 2-legged standing positions under the conditions of eyes closed and eyes open, proprioception at 20° of plantar flexion, as well as anxiety and depression in athletes with CAI. However, the findings revealed that NMT+NFT and NMT alone could both improve such indices. NMT+NFT as a treatment protocol improved postural control, ankle proprioception, anxiety, and depression greater than NMT alone. A combined protocol of NFT and NMT led to greater improvement compared with NMT alone. NFT was recommended as an adjunct therapy in the rehabilitation of athletes suffering from CAI.

Predictors of static and dynamic balance control in kidney transplant recipients.

We aimed to evaluate balance control and lower extremity muscle strength in kidney transplant recipients (KTRs) including acomparison to ahealthy control group and determine the predictors of static and dynamic balance control after kidney transplantation. In this study 40 KTRs and 40healthy controls were included. Balance control was assessed using the Biodex balance system. The static postural stability test (SPST) and clinical test of sensory integration and balance (CTSIB) were used to assess static balance control whereas the dynamic postural stability test (DPST) and limits of stability test (LOST) were used for dynamic balance control. Lower extremity muscle strength was measured with ahand-held dynamometer. Renal functions and laboratory findings of KTRs were recorded. All the stability index scores of SPST and sway index in CTSIB were significantly higher in KTRs compared to healthy controls. The right anteroposterior stability index score in DPST and the reaction time in LOST were significantly higher whereas overall score in LOST and lower extremity muscle strength were significantly lower in KTRs. The linear regression analysis revealed that hemoglobin was the predictor of static balance control accounting for 11% of the variance and body weight was the predictor of dynamic balance control accounting for 34% of the variance. Balance control, both static and dynamic, are impaired in KTRs as well as lower extremity muscle strength. Hemoglobin level is apredictor of static balance control whereas body weight is apredictor of dynamic balance control after kidney transplantation.

The effect of warm-up on postural sway in the dominant and non-dominant leg

Although the chronic effects of a long-term warm-up program have been widely studied, to our knowledge, the number of studies examining the acute effects of a single warm-up session on inter-limb balance asymmetries in symmetrical sports such as cycling is limited. The aim of this study was to examine the effect of warm-up on postural sway in the dominant and non-dominant leg in male bicycle athletes. Sixteen healthy young male volunteers who engage in cycling sports participated in the study. The participants' age was determined as 15.50±1.15 years, body weight as 56.06±7.79 kg, height as 169.87±4.98 cm, and sports experience as 4.31±1.25 years. The postural control performance on the dominant and non-dominant leg of the athletes was evaluated on Biodex Balance System balance device platform for 20 seconds before and after a 10-minute warm-up exercise performed at a constant pedaling frequency of 80 RPM on a bicycle ergometer. In the comparison of the pre-test to post-test dominant leg Overall Sway Index (t=3.456; p=0.004), Anterior-Posterior (Z=-3.160; p=0.002) and Medial-Lateral (Z=-2.428; p=0.015) postural control scores of the participants, a significant decrease was found in the post-test. It was determined that warm-up exercise can only improve acute postural control in the dominant leg. The effects of the study can be extended to different sports branches with symmetrical features in order to obtain comparable results.

Effect of ovulation on postural sway in association with sex hormone variation across the menstrual cycle in college students: an observational study

BackgroundPoor balance associated with increased postural sway is a risk factor for the high incidence of injuries found during specific menstrual cycle phases. This fact led to the hypothesis that female reproductive hormones affect soft tissue and neuromuscular function, reducing postural balance and resulting in a high injury prevalence among female college students. So, the current study aimed to identify the influence of ovulation in association with sex hormone variation across the menstrual cycle on postural sway in college students.Material and methodsForty female college students were enrolled in this study. They were recruited among physical therapy students at Deraya University, New Minya, Egypt. They were aged from 17 to 22 years. They were allocated to a single group. Progesterone and estradiol blood levels were measured to detect the timing of the follicular and luteal phases, and a urine luteinizing hormone (LH) strip test was used to determine when ovulation occurred. The dynamic postural sway index was assessed by using the Biodex Balance system. All measurements were taken on the early follicular (1st–3rd) day, the ovulatory (11th–13th) day, and the mid-luteal phase (21st–23rd) day from the onset of menstruation.ResultsStatistical analysis showed that the anteroposterior, mediolateral, and overall sway index increased significantly during the ovulatory phase compared to the earlier follicular and mid-luteal menstrual cycle phases in female college students (P < 0.05). There was no significant variance between the early follicular and mid-luteal phases (P > 0.05).ConclusionsIt can be concluded that increased female sex hormones during ovulation affect postural sway, which may disturb balance and increase the risk of injuries in college students.

Determining an optimal posturography dataset to identify standing behaviors in the post-stroke subacute phase. Cross-sectional study.

A key issue for posturography is the expression of robust results, in a simplified way. Most studies of individuals post-stroke concern the chronic phase, with small sample sizes. By reducing the number of posturographic indices, we aimed to determine an optimal dataset and understand typical postural behaviors in the subacute post-stroke phase. In this cross-sectional study ancillary to the DOBRAS cohort, individuals were assessed as soon they could complete a full posturography session (with and without vision) after a first hemispheric stroke. Body-weight distribution on the mediolateral (ML) axis, position of the center of pressure on the antero-posterior (AP) axis, and postural sway on both axes were computed. Balance ability in daily life was quantified with the Postural Assessment Scale for Stroke. Data were analyzed by principal component and hierarchical clustering analyses as well as multiple linear regression. We enrolled 95 individuals (median age: 67.0 years [Q1; Q3 56.0; 72.0]; 68% males). Vision suppression had a marginal effect, only increasing postural sway. Regardless of the visual condition, posturographic behavior was captured by a set of 3 indices that explained almost all the information. One postural sway index (ML or AP) gave more information (48%) than both position indices (ML 26% and AP 15%). These 3 indices identified 3 standing behaviors: 1) stable and symmetric, 2) asymmetric, unstable, and positioned backward, and 3) very unstable and positioned forward. Balance ability in daily life was explained (49% of the information, 95%CI [35; 63]) by weight-bearing asymmetry and postural sway on the ML axis, which played an independent role (both p<10-5), with similar impact. Three typical behaviors allow standing after stroke: described by only 3 posturographic indices. Weight-bearing asymmetry is not the primary parameter and should not be considered in isolation as an outcome. To increase the feasibility of posturography in the early subacute phase and to simplify evaluation sessions, trials could be limited to eyes open. NCT03203109.

A randomized controlled trial on impact of group exercise programme on fall risk, balance, strength, fear of fall and quality of life of older adults

Introduction. A parallel group Randomized Controlled Trial was aimed to determine the impact of a group exercise programme on fall risk and its modifiable risk factors in older adults. Methods. 86 older adults having increased fall risk were assigned to group exercise programme or individualized exercise programme. Intervention consisted of warm up, balance retraining exercises and cooldown and lower limb strengthening exercises derived from Otago Exercise Programme (OEP) forming the core program for 2 times in a week for the period of 10 weeks. Demographic data, Timed Up and Go test, 5-times sit to stand test, sway index and dynamic postural stability, fear of fall and physical and mental components of Quality of Life were assessed before and after 10 weeks and after 6 months of intervention. Results. A significant intra-group effect was demonstrated for both groups at post-intervention in all the outcomes, (p &lt; 0.005). No differences were observed between groups for any outcome (p &gt; 0.005) except SF 12 score which was improved more in experimental group (p &gt; 0.005). Conclusions. Group exercise program was effective in reducing fall risk and fear of fall, improving balance and lower extremity strength and enhancing the quality of life of older adults.

Game-like interactive exercise versus visual feedback in patients with chemotherapy induced peripheral neuropathy post mastectomy: A randomized comparative study

Background Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most frequent side effects of antineoplastic agents, with a prevalence of 19 to 85%. In terms of clinical manifestations, CIPN is primarily a sensory neuropathy with motor and autonomic alterations of varying intensity and duration. CIPN consider as major problem for both cancer patients and survivors, as well as for their healthcare providers, possibly increasing the risk of falling. Objective: To evaluate the efficacy of game-like interactive exercise versus visual feedback training on the risk of falling and sensory integration in patients with chemotherapy-induced peripheral neuropathy after mastectomy. Methods: In this randomized comparative study, 30 female patients diagnosed with chemotherapy-induced peripheral neuropathy after mastectomy were randomly allocated into two equal groups; group (A) underwent game-like interactive exercise using the Biodex Balance System (BBS), while group (B) underwent a visual feedback training program using BBS. The treatment was applied for three sessions per week for four consecutive weeks. All subjects in both groups were assessed using the fall risk index and sensory integration test (sway index) in four sensory conditions at baseline and at the end of the study for both groups.

The Effect of Different Physiotherapy Programs on Pain, Balance and Trunk Functional Capacity in Adolescents with Low Back Pain

Background. Low back pain is a common problem, adversely affecting balance and strategy for controlling the trunk muscles. There are various methods to treat low back pain, therefore, studies comparing the effectiveness of different programs can help improve the rehabilitation program for patients with low back pain.&#x0D; The aim. To evaluate the effect of trunk stabilization and balance exercises performed with different devices on pain, balance and trunk functional capacity in adolescents with low back pain.&#x0D; Methods. 12 adolescents with low back pain participated in this study. They were divided into two groups. The first group received 20 minutes of stabilization exercises and 10 minutes of balance training using the Biodex balance system. The second group received 20 minutes of stabilization exercises and 10 minutes of balance training using a vibration platform. All subjects were evaluated before and after 10 physiotherapy procedures. Self-reported pain, balance and static endurance of trunk muscles were assessed before and after the interventions.&#x0D; Results. Both programs significantly reduced pain, improved control of the center of gravity within the base of support, reduced the time required to shift weight in different paths, reduced sway index in conditions of eyes open or eyes closed on a firm or foam surface, improved dynamic and static overall postural stability and increased static endurance of trunk muscles. Improvement in control of the center of gravity within the base of support, and reduction in the time required to shift weight in different paths, were more significant in the group that received balance training using the Biodex balance system compared with that in the group that received balance training using a vibration platform.&#x0D; Conclusions. Balance training using the Biodex balance system was more effective in improving control of the center of gravity within the base of support and reducing the time required to shift weight in different paths than balance training using a vibration platform.&#x0D; Keywords: low back pain, balance, trunk stability, Biodex balance system, vibration platform.&#x0D; &#x0D;

Changes in Postural Control Ability after Wearing Corrective Glasses for Distance in Older Adults and Their Causes.

Deterioration of postural control in older adults is unavoidable due to age-associated degeneration of the visual system. Our study objective was therefore to verify whether there is a positive effect on postural control ability after providing older adults, whose postural control function had deteriorated, with corrective glasses to correct refractive errors. Twenty-seven participants, 66 to 90 years of age, were included in this study. Stability index, synchronization index, and sway power index were measured by using the TETRAX balance system and comparatively analyzed before and after wearing the corrective glasses for distance. The stability index after wearing corrective glasses significantly decreased compared to before wearing them (p < 0.05). Four synchronization areas, among six, showed a significant increase in the synchronization index after wearing corrective glasses compared to before wearing them (p < 0.05). The sway power index significantly decreased in the mid–high and the high frequency after wearing the corrective glasses (p < 0.05). Optimal visual information can be obtained through the correction of residual refractive errors, eliciting a positive effect on the overall posture control by improving the sensory integration ability with the somatic nervous system responsible for posture control, maximizing the lower extremity motor function of the elderly.

Effects of Soccer Exercise on Balance Ability and Kinesthesia of the Lower Limb Joints in Children Aged 5-6 Years.

Age-, height- and weight-matched children were recruited to the experimental group (EG; n = 31) and control group (n = 32). Following a 16-week soccer training program, balance ability and dominant-side lateral knee and ankle kinesthesia changes were tested. Regarding balance ability, the Sway Index, when children stood on a firm or foam surface with their eyes closed in the static balance test, and the dynamic balance test time were 13.5%, 11.6%, and 14.3% lower in the EG than in the control group, respectively. The scores in the left and right directions were 23.7% and 24.2% higher in the EG, respectively. Regarding kinesthesia, the angle of knee extension and ankle metatarsal flexion and dorsiflexion were 13.4%, 20.0%, and 16.8% lower in the EG than in the control group. These results indicate children in the EG had a better performance. After soccer exercise, children aged 5-6 years displayed improved balance in the left and right directions and improved knee extension, ankle plantarflexion, and dorsiflexion kinesthesia.

Test-Retest Reliability of Postural Control Assessment on Biodex BioSway™.

Background Recent protocols for posturographic assessment of postural control and balance have included head shake test conditions to challenge the vestibular contributions of postural control in an effort to increase the diagnostic accuracy of identifying individuals with impaired balance. However, evidence is limited regarding the test-retest reliability of such assessment protocols. Purpose The purpose of this study was twofold: to determine the test-retest reliability of postural control assessment on the Biodex Biosway™, an accessible and field expedient tool for posturographic assessment, and to determine the test-retest reliability of the Head Shake Sensory Interaction and Balance Test (HS-SIB), an adaptation of the modified Clinical Test of Sensory Interaction and Balance (mCTSIB) which adds two head shake conditions to challenge the vestibular contributions to postural control. Study Design. This was a correlational time series cohort study completed in a biomechanics laboratory. Methods The sample consisted of nineteen healthy adults (10 females, 9 males). Sway Index, Equilibrium Score, and the area of the ellipse enclosing 95% of the anterior-posterior (AP) and medial-lateral (ML) center of gravity (COG) displacement (AREA95) are the 3 summary variables. Standard Error of Measurement (SEM) and Minimum Detectable Change (MDC) are also reported. Results Test-retest reliability was generally poor with limited exceptions. Moderate to good reliability was observed for the more challenging stance conditions (ICC range 0.58-0.81), including those with head shake. Conclusions Field-expedient systems, such as the Biodex BioSway™, may offer reliable posturographic testing where gold-standard methods are not available. Clinicians should be aware that less demanding test conditions have limited reliability; however, test-retest reliability of this assessment tool is improved with more challenged stance conditions and the inclusion of a head shake task.

The Evaluation of Gait and Balance for Patients with Early Diabetic Peripheral Neuropathy: A Cross-Sectional Study.

ObjectiveFalls often occur in patients with diabetic neuropathy due to biomechanical alternation. The implication of diabetic peripheral neuropathy (DPN) on gait and balance remains poorly understood.MethodsA total of 11 dynamic gait, balance and electrophysiological parameters were evaluated in 176 participants. The biomechanical parameters were compared between groups.ResultsStride length and stride velocity were significantly lower in all subgroups of DPN compared with healthy subjects (p<0.05). Stance phase and double support phase were significantly higher, but swing phase were significantly lower across all subgroups of DPN than healthy subjects (p<0.05). Under eyes-open standing, the ML and AP range parameters of CoM sway, ankle sway and hip sway, CoM sway index, ankle swing index in both subclinical and confirmed DPN patients were all significantly higher compared to healthy subjects (p<0.05). Under eyes-closed standing, AP range parameters of CoM sway in subclinical DPN and confirmed DPN patients were significantly higher than healthy subjects (p<0.05). The hip sway areas in diabetics were significantly higher compared to healthy subjects (p<0.05).ConclusionThe abnormal biomechanical parameters existed in the early stages of patients with DPN. The static balance under eyes-open and eye-closed condition is maintained by ankle joint compensation strategy and hip joint protection strategy. An early evaluation and better risk management is essential for diabetic patients with a history of more than 5 years even without DPN clinical symptoms and signs.Clinical Trial Registration NumberNo. ChiCTR1800019179, www.chictr.org.cn.

Maze Control Training on Kinesthetic Awareness in Patients with Stroke: A Randomized Controlled Trial.

Objective To determine the influence of adding maze control training to the selected conventional physical therapy on kinesthetic awareness in patients with chronic stroke. Methods Thirty adult patients of both genders with chronic cerebral stroke were assigned to control and experimental groups randomly: the control group (A) received the selected conventional physical therapy rehabilitation program, while the experimental group (B) received the same program as group A in addition to the maze control training. Measurements for sway index, risk of fall, and knee proprioception before and after 8 weeks of treatment (24 sessions; three times per week). Results There were significant decreases of both sway index and risk of fall in both groups (p ≤ 0.001 in all measures), significant improvements of the knee proprioception in 30° and 75° in the experimental group (p value = 0.016 and ≤0.001, respectively). The in-between groups' comparison showed significant differences corresponding to both the sway index and risk of fall (p ≤ 0.001), and a significant difference in 75° (p ≤ 0.001). Conclusion Adding maze control training to the selected conventional physical therapy improved the kinesthetic awareness in patients with chronic stroke.

Comparison of Concurrent and Same-Day Balance Measurement Approaches in a Large Sample of Uninjured Collegiate Athletes.

BackgroundMeasures of postural stability are useful in assisting the diagnosing and managing of athlete concussion. Error counting using the Balance Error Scoring System (BESS) is the clinical standard, but has notable limitations. New technologies offer the potential to increase precision and optimize testing protocols; however, whether these devices enhance clinical assessment remains unclear.PurposeTo examine the relationships between metrics of balance performance using different measurement systems in uninjured, healthy collegiate athletes.Study DesignCross-sectional.MethodsFive hundred and thirty uninjured collegiate athletes were tested using the C3Logix app, which computes ellipsoid volume as a measure of postural stability during the six standard BESS conditions, while concurrently, errors were manually counted during each condition per standard BESS protocols. The association between concurrently measured ellipsoid volumes and error counts were examined with Spearman’s correlations. From this sample, 177 participants also performed two double-leg conditions on the Biodex BioSway force plate system on the same day. This system computes Sway Index as a measure of postural stability. The association of ellipsoid volume (C3Logix) and Sway Index (Biodex) was examined with Spearman’s correlations. Individual-level data were plotted to visually depict the relationships.ResultsC3Logix ellipsoid volume and concurrently recorded error counts were significantly correlated in five of the six BESS conditions (rs:.22-.62; p< 0.0001). C3Logix ellipsoid volume and Biodex Sway Index were significantly correlated in both conditions (rs=.22-.27, p< 0.004). However, substantial variability was shown in postural stability across all three measurement approaches.ConclusionModest correlation coefficients between simultaneous and same-day balance assessments in uninjured collegiate athletes suggest a need to further optimize clinical protocols for concussion diagnosis.Level of Evidence2b

Influence of force-time parameters of hip abductors on maintaining balance in frontal plane in young healthy females

Purpose: The aim of this study was to determine the impact of isometric and isokinetic hip abductor muscle strength on the quality of maintaining static balance in healthy subjects. Methods: The study enrolled 51 healthy women aged 18–25. Balance assessment was carried out according to the M-CTSIB protocol and Single Leg Stance Test (with eyes open and closed) using the Biodex Balance System. An isokinetic evaluation conducted at 30 °/s and an isometric evaluation of the hip abductors were performed with the Humac Norm system. Results: Regression analysis for Sway Index (SW) and Stability Index (ST) in bipedal standing showed a significant importance of the presence of visual feedback (RSW EO = –0.922; p &lt; 0.0001; RST EO = –0.613; p = 0.0493), and unstable surface (RSW US = 1.253; p &lt; 0.0001; RSW US = 2.547; p &lt; 0.0001). Regression analysis for single-leg stance showed correlations between the following indices: overall sway index (OR) in single-leg stance, the antero-posterior (AP) sway index and the medio-lateral (ML) sway index on the one hand and isometric abduction time to peak torque (ROR TPT = 0.769; p = 0.0005; RAP TPT = 0.565; p = 0.008; RML TPT = –1.74; p &lt; 0.05, respectively) as well as the test conditions on the other. Conclusions: Physiological activation of the hip abductors may be important for physiological maintenance of postural balance in young people, in both leg standing as well as in single-leg stance. The present results warrant prospective, randomized studies of larger groups that are diversified with regard to age and gender of the participants.