DIFFERENCES IN HIP MUSCLE STRENGTH AND STATIC BALANCE IN PATIENTS WITH TRANSFEMORAL AMPUTATIONS CLASSIFIED AT DIFFERENT K-LEVELS: A PRELIMINARY CROSS-SECTIONAL STUDY

BACKGROUND: Following amputation, patients with lower limb amputations (LLA) are classified into different functional mobility levels (K-levels) ranging from K0 (lowest) to K4 (highest). However, K-level classification is often based on subjective criteria. Objective measures that are able to differentiate between K-levels can help to enhance the objectivity of K-level classification. OBJECTIVE(S): The goal of this preliminary cross-sectional study was to investigate whether differences in hip muscle strength and balance parameters exist among patients with transfemoral amputations (TFA) assigned to different K-levels. METHODOLOGY: Twenty-two participants with unilateral TFA were recruited for this study, with four participants assigned to K1 or K2, six assigned to K3 and twelve assigned to K4. Maximum isometric hip strength of the residual limb was assessed in hip flexion, abduction, extension, and adduction using a custom-made diagnostic device. Static balance was investigated in the bipedal stance on a force plate in eyes open (EO) and eyes closed (EC) conditions. Kruskal-Wallis tests were used to evaluate differences between K-level groups. FINDINGS: Statistical analyses revealed no significant differences in the parameters between the three K-level groups (p>0.05). Descriptive analysis showed that all hip strength parameters differed among K-level groups showing an increase in maximum hip torque from K1/2-classified participants to those classified as K4. Group differences were also present in all balance parameters. Increased sway was observed in the K1/2 group compared to the K4 group, especially for the EC condition. CONCLUSION: Although not statistically significant, the magnitude of the differences indicates a distinction between K-level groups. These results suggest that residual limb strength and balance parameters may have the potential to be used as objective measures to assist K-level assignment for patients with TFA. This potential needs to be confirmed in future studies with a larger number of participants. Layman's Abstract Patients with lower limb amputation (LLA) are classified into different mobility levels, so-called K-levels, which are ranging from K0 (lowest) to K4 (highest). K-level classification is relevant for the patients as it determines the type of prosthetic components available. However, K-level can vary greatly based on the clinician or orthopedic technician individual assessment. Objective data from physical performance tests can help to improve K-level classification. Therefore, muscle strength tests of the amputation stump as well as balance tests were performed in this study to determine whether these parameters have the potential to support K-level classification. Twenty-two participants with a thigh amputation participated in the study (four K1/2-, six K3- and twelve K4-participants). Hip muscle strength on the amputation side was assessed as well as static balance in the double leg stance with eyes open and eyes closed. Analysis of the data showed that all hip strength parameters differed between the K-level groups, with maximum strength increasing from the K1/2 group to the K4 group. Group differences were also seen in the balance parameters with greater body sway for the K1/2 group when compared to the K4 group, especially when participants had their eyes closed. These results show that muscle strength tests of the residual limb and static balance tests may serve as additional measures to improve K-level assignment for patients with LLA. This was only an initial study and further studies with a larger number of participants are required to confirm these results. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/37456/28905 How To Cite: John S, Orlowski K, Mrkor K.U, Edelmann-Nusser J, Witte K. Differences in hip muscle strength and static balance in patients with transfemoral amputations classified at different K-levels: A preliminary cross-sectional study. Canadian Prosthetics & Orthotics Journal. 2022; Volume 5, Issue 1, No.5. https://doi.org/10.33137/cpoj.v5i1.37456 Corresponding Author: Stefanie John,Department of Sports Science, Faculty of Humanities, Otto von Guericke University, Magdeburg, Germany.E-Mail: [email protected] ID: https://orcid.org/0000-0001-6722-7195

Postural stability disorders—early signs of aging—in physically non-active prisoners

Background There is a need for a study of possible relationship between serving a prison sentence and developing postural stability dysfunction. The aim of the study was to analyze postural stability of physically inactive prisoners. The study group consisted of 24 male prisoners aged 34.6 ± 7.02 years, imprisoned in closed prison and 30 healthy, non-active physically, aged 36.9 ± 7.5 years, who consisted control group. The subjects were imprisoned for a mean of 105.43 ± 58.48 months. Methods The static balance test was conducted on bi-modular stabilometric platform CQStab2P. Results We found statistically significant differences in several stability parameters. Prisoners results were significantly worse in parameters measured with eyes open: MA (mean amplitude p < 0.01), MAAP (mean amplitude in anterio–posterior plane p < 0.03), MAML (mean amplitude in medio—lateral plane p < 0.04), MaxAP (maximal sway in AP p < 0.01), MaxML (p < 0.01). With eyes closed the prisoner’s results were significantly worse in SPML (sway path in medio-lateral plane p = 0.01), better in MAML (p < 0.01) and MaxML (p < 0.01), and faster in MVML (mean velocity in medio-lateral plane p < 0.01). Conclusions (1) Diagnostics aimed at early diagnoses of ageing symptoms should be performed in prisons. It would allow for better prisoner management in terms of assessment of ability to work, free time activity offer and falls prevention. (2) In prisons, in addition to counteracting the typical causes of balance disorders, action should be taken to counteract the causes for balance disorders typical for prison environment, inter alia: sensory deprivation—by implementing programmes comprehensively activating prisoners, and hypokinesis—by implementing physical activity programmes that cater for the needs of older prisoners.

Static Postural Control Deficits in Adults with Myotonic Dystrophy Type 1, Steinert Disease

Background: Myotonic dystrophy type 1 (DM1) is characterized by progressive and predominantly distal muscle atrophy and myotonia. Gait and balance impairments, resulting in falls, are frequently reported in this population. However, the extent to which individuals with DM1 rely more on a specific sensory system for balance than asymptomatic individuals (AI) is unknown. Objective: Evaluate postural control performance in individuals with DM1 and its dependence on vision compared to AI. Methods: 20 participants with DM1, divided into two groups based on their diagnosis, i.e. adult and congenital phenotype, and 12 AI participants were recruited. Quiet standing postural control was assessed in two visual conditions: eyes-open and eyes-closed. The outcomes measures were center of pressure (CoP) mean velocity, CoP range of displacement in anteroposterior and mediolateral axis, and the 95% confidence ellipse’s surface. Friedman and Kruskal-Wallis analysis of variance were used to compare outcomes between conditions and groups, respectively. Results: Significant group effect and condition effect were observed on postural control performance. No significant difference was observed between the two DM1 groups. The significant differences observed between the AI group and the two DM1 groups in the eyes-open condition were also observed in the eyes-closed condition. Conclusions: The result revealed poorer postural control performance in people with DM1 compared to AI. The DM1 group also showed similar decrease in performance than AI in eyes-closed condition, suggesting no excessive visual dependency.

The effects of ankle Kinesiotaping on postural control in healthy taekwondo athletes

Background and Study Aim. Although Kinesiotape is widely used by athletes, information about its effect is unclear. Its effect on postural control might directly affect an athlete's performance. In this study, it is aimed to find out whether ankle Kinesiotaping in taekwondo athletes affects postural control. Material and Methods. Twenty-four healthy university students – taekwondo athletes (12 females, 12 males) were included in the study voluntarily (Age 21.00 ± 1.53 years; height 173.33 ± 7.29 cm; body weight 63.41 ± 9.41 kg). Kinesiotape was carried out to the dominant ankle of the participants. Kinesiotape was applied supportively to peroneus longus, peroneus brevis, and tibiofibular ligament. All participants were taken to postural control measurements twice with Kinesiotape (KT) and without KT. Postural control was measured using the Biodex Balance System with eyes open (EO) and eyes closed (EC). Overall Stability Index (OSI), anterior-posterior sway (AP) and medio-lateral sway (ML) scores were used in the evaluation of postural control. Wilcoxon test was used to compare balance scores under EO condition, and the t-test was used for dependent groups to compare balance scores under EC condition. Results. In EO condition, no significant difference was found between OSI, AP, and ML scores of the taekwondo athletes with KT and without KT (p > 0.05). In EC condition, no significant difference was found between OSI, AP, and ML scores of male taekwondo athletes with KT and without KT (p > 0.05). It was found that Kinesiotape in EC condition decreased OSI and AP sway scores in female taekwondo athletes (p < 0.05). Conclusions. It was determined that ankle Kinesiotaping of taekwondo athletes did not change the postural balance in EO condition. In EC condition it did not change the postural sway of male taekwondo athletes, but it improved the postural control performances of female taekwondo athletes.

Effects of familiarity with musical style on music-evoked emotions: An EEG study

Learning mechanisms have been postulated to be one of the primary reasons why different individuals have similar or different emotional responses to music. While existing studies have largely examined mechanisms related to learning in terms of cultural familiarity or recognition, few studies have conceptualized it in terms of an individual’s level of familiarity with musical style, which could be a better reflection of an individual’s composite musical experiences. Therefore, the current study aimed to bridge this research gap by investigating the electrophysiological correlates of the effects of familiarity with musical style on music-evoked emotions. 49 non-musicians listened to 12 musical excerpts of a familiar musical style (Japanese animation soundtracks) and eight musical excerpts of an unfamiliar musical style (Greek Laïkó music) with their eyes closed as electroencephalography is being recorded. Participants rated their felt emotions after each musical excerpt is played. Behavioral ratings showed that music of the familiar musical style was felt as significantly more pleasant as compared to the unfamiliar musical style while no significant differences in arousal were observed. In terms of brain activity, music of the unfamiliar musical style elicited higher (1) theta power in all brain regions (including frontal midline), (2) alpha power in frontal region, and (3) beta power in fronto-temporo-occipital regions as compared to the familiar musical style. This is interpreted to reflect the need for greater attentional resources when listening to music of an unfamiliar style, where listeners are less familiar with the syntax and structure of the music as compared to music of a familiar style. In addition, classification analysis showed that unfamiliar and familiar musical styles can be distinguished with 67.86% accuracy, Thus, clinicians should consider the musical profile of the client when choosing an appropriate selection of music in the treatment plan, so as to achieve better efficacy.

Examining the Relationship Between a Neuromuscular Control Baseline Battery for Sport-Related Concussion and Anterior Cruciate Ligament Injury Risk

ObjectiveTo examine the relationship between the m-CTSIB and Landing Error Scoring System in a sample of collegiate female athletes.BackgroundRecent literature has linked concussion and neuromuscular deficits in the lower extremity after injury. Neuromuscular control is frequently assessed using balance measures for concussion, but also dynamically to identify anterior cruciate ligament injury (ACL) risk via jump-landing movement screening.Design/MethodsThirty-nine healthy, collegiate female soccer (n = 22) and volleyball (n = 17) athletes completed the modified-Clinical Test of Sensory Interaction of Balance (m-CTSIB) and the Landing Error Scoring System (LESS). Measures consisted of total m-CTSIB sway index scores on individual conditions (firm surface eyes open [condition 1] and eyes closed [2], foam surface eyes open [3] and eyes closed [4]), m-CTSIB overall score, and total LESS errors. LESS scores were also categorized into a low (0–4 errors) and high (5 + errors) risk to determine if athletes with worse neuromuscular control on the LESS has worse balance on the m-CTSIB. A Spearman's rank-order correlation was conducted to determine the strength of the relationship between LESS and m-CTSIB performance. A series of Mann-Whitney U test were performed to determine differences between low and high LESS performance on m-CTSIB performance.ResultsThere was a weak, negative correlation between LESS and m-CTSIB performance (rs(37) = −0.153, p = 0.35). Further, there were no differences between the low and high risk LESS groups on sway index scores on conditions 1 (U = 158.5, p = 0.39), 2 (U = 156.0, p = 0.36), 3 (U = 165.5, p = 0.51), or 4 (U = 128.5, p = 0.08), as well as overall m-CTSIB scores (U = 150.5, p = 0.28).ConclusionsThere appears to be a lack of relationship between the LESS and m-CTSIB tests, revealing the independence of static and dynamic lower extremity neuromuscular function. Athletes who may be more at risk for ACL injury due to abnormal jump-landing biomechanics, do not differ from low-risk athletes on baseline balance assessment.

The Effect of Sex, Sport Participation, and Concussion History on Baseline Concussion Balance Test Performance in Division-I Collegiate Athletes

ObjectiveExplore the effect of baseline characteristics such as sex, sport, and concussion history on the Concussion Balance Test (COBALT) performance in collegiate athletes.BackgroundThe COBALT is a recently developed clinical balance assessment specifically for athletic populations following concussion. The task conditions of the COBALT are designed to challenge sensory integration and reweighting processing underlying postural control. It has been documented that balance performance is influenced by factors such as sex and sport in collegiate athletes.Design/MethodsOne-hundred twenty seven collegiate athletes (77 male, 50 female; age: 19.81 ± 1.39; height: 68.77 ± 5.57 in; mass: 80.98 ± 26.15 kg), who participated in Division-I football, soccer, or cheerleading were included. Participants completed the 4 baseline conditions (Condition 3, 4, 7, 8) of the COBALT. Condition 3 (C3) included a side-to-side headshake with eyes closed. For Condition 4 (C4) the participant stood with hands clasped, elbows extended, and thumbs up while rotating their trunk side-to-side, visually focusing on their thumbs. Conditions 7 (C7) and 8 (C8) repeated C3 and C4 on a foam surface. Two 20-second trials of each condition were completed on a forceplate and the mean angular sway velocity (°/s) were calculated and number of errors were counted. ANOVAs and ANCOVAs were used to assess the potential effects on COBALT performance.ResultsThere were no significant differences in postural sway for any COBALT condition based on sex (p > 0.05). Females demonstrated more errors than males on C7 (p < 0.001). Cheerleaders had more balance errors compared to football athletes for C3 and C7 (p < 0.05) and soccer athletes for C7 (p < 0.05). Concussion history did not have an effect on COBALT performance (p > 0.05).ConclusionsUnderstanding factors that may influence COBALT performance at baseline may enhance concussion evaluation in collegiate athletes with suspected balance deficits following concussion. While concussion history had no effect, sex and sports participation may influence performance and should be considered when interpreting COBALT results post-concussion.

A Wearable Head Mounted Display Bio-Signals Pad System for Emotion Recognition

Multimodal bio-signals acquisition based on wearable devices and using virtual reality (VR) as stimulus source are promising techniques in emotion recognition research field. Numerous studies have shown that emotional states can be better evoked through Immersive Virtual Environments (IVE). The main goal of this paper is to provide researchers with a system for emotion recognition in VR environments. In this paper, we present a wearable forehead bio-signals acquisition pad which is attached to Head-Mounted Displays (HMD), termed HMD Bio Pad. This system can simultaneously record emotion-related two-channel electroencephalography (EEG), one-channel electrodermal activity (EDA), photoplethysmograph (PPG) and skin temperature (SKT) signals. In addition, we develop a human-computer interaction (HCI) interface which researchers can carry out emotion recognition research using VR HMD as stimulus presentation device. To evaluate the performance of the proposed system, we conducted different experiments to validate the multimodal bio-signals quality, respectively. To validate EEG signal, we have assessed the performance in terms of EEG eyes-blink task and eyes-open and eyes-closed task. The EEG eyes-blink task indicates that the proposed system can achieve comparable EEG signal quality in comparison to the dedicated bio-signals measuring device. The eyes-open and eyes-closed task proves that the proposed system can efficiently record alpha rhythm. Then we used signal-to-noise ratio (SNR) and Skin Conductance Reaction (SCR) signal to validate the performance for EDA acquisition system. A filtered EDA signal, with a high mean SNR of 28.52 dB, is plotted on HCI interface. Moreover, the SCR signal related to stimulus response can be correctly extracted from EDA signal. The SKT acquisition system has been validated effectively by the temperature change experiment when subjects are in unpleasant emotion. The pulse rate (PR) estimated from PPG signal achieved the low mean average absolute error (AAE), which is 1.12 beats per minute (BPM) over 8 recordings. In summary, the proposed HMD Bio Pad offers a portable, comfortable and easy-to-wear device for recording bio-signals. The proposed system could contribute to emotion recognition research in VR environments.

Validity and Reliability of a Smartphone App for Gait and Balance Assessment

Advances in technology provide an opportunity to enhance the accuracy of gait and balance assessment, improving the diagnosis and rehabilitation processes for people with acute or chronic health conditions. This study investigated the validity and reliability of a smartphone-based application to measure postural stability and spatiotemporal aspects of gait during four static balance and two gait tasks. Thirty healthy participants (aged 20–69 years) performed the following tasks: (1) standing on a firm surface with eyes opened, (2) standing on a firm surface with eyes closed, (3) standing on a compliant surface with eyes open, (4) standing on a compliant surface with eyes closed, (5) walking in a straight line, and (6) walking in a straight line while turning their head from side to side. During these tasks, the app quantified the participants’ postural stability and spatiotemporal gait parameters. The concurrent validity of the smartphone app with respect to a 3D motion capture system was evaluated using partial Pearson’s correlations (rp) and limits of the agreement (LoA%). The within-session test–retest reliability over three repeated measures was assessed with the intraclass correlation coefficient (ICC) and the standard error of measurement (SEM). One-way repeated measures analyses of variance (ANOVAs) were used to evaluate responsiveness to differences across tasks and repetitions. Periodicity index, step length, step time, and walking speed during the gait tasks and postural stability outcomes during the static tasks showed moderate-to-excellent validity (0.55 ≤ rp ≤ 0.98; 3% ≤ LoA% ≤ 12%) and reliability scores (0.52 ≤ ICC ≤ 0.92; 1% ≤ SEM% ≤ 6%) when the repetition effect was removed. Conversely, step variability and asymmetry parameters during both gait tasks generally showed poor validity and reliability except step length asymmetry, which showed moderate reliability (0.53 ≤ ICC ≤ 0.62) in both tasks when the repetition effect was removed. Postural stability and spatiotemporal gait parameters were found responsive (p < 0.05) to differences across tasks and test repetitions. Along with sound clinical judgement, the app can potentially be used in clinical practice to detect gait and balance impairments and track the effectiveness of rehabilitation programs. Further evaluation and refinement of the app in people with significant gait and balance deficits is needed.

Impact of Body Mass Index on Static Postural Control in Adults With and Without Diabetes: A Cross-Sectional Study

AimThe objective of this research was to determine the static postural control differences measured from a force platform in Type 2 diabetes mellitus (T2DM) and healthy control groups with different levels of body mass index (BMI), and detect the static postural control difference between T2DM and healthy control groups stratified by different BMI category. This research also explored the relationship of BMI and static postural performance.MethodsWe recruited 706 participants with T2DM and 692 healthy controls who were sufficiently matched for age, gender, and BMI in this cross-sectional study. The participants were stratified into three groups by BMI: normal weight, overweight, and obesity. All participants performed two-legged static stance postural control assessment on a firm force platform. The Center of Pressure (CoP) parameters were collected under eyes-open and eyes-closed conditions. Mann–Whitney U test was used to compare the static postural control parameters within each BMI category in both groups. The static postural control parameters among different weight groups were compared by Kruskal–Wallis test, post hoc pair-wise comparison were conducted. Generalized linear model was conducted to examine the association between BMI and static postural control parameters while controlling for confounding factors.ResultsHealthy control group had statistical difference in most CoP parameters compared to T2DM group based on all BMI categories. Normal weight participants presented significant difference compared with overweight and/or obesity for total track length (TTL) and velocity of CoP displacements in Y direction (V-Y) under eyes-open condition, and for most CoP parameters under eyes-closed condition in both groups. There were statistically significant correlations between BMI and most static postural control parameters under only eyes-closed condition according to the result of generalized linear model.ConclusionT2DM patients had impaired static postural control performance compared to healthy controls at all BMI categories. The findings also indicated the association between BMI and static postural control, where higher BMI individuals showed more static postural instability in both T2DM and healthy controls.