Sit-to-stand biomechanics of individuals with multiple sclerosis

Trunk biomechanical changes between the sit-to-stand and stand-to-sit performed at self-selected and fast speeds in stroke survivors

PURPOSE

To compare the trunk biomechanical characteristics between the sit-to-stand and stand-to-sit performed at self-selected and fast speeds in stroke survivors and healthy-matched controls.

METHODS

Thirty individuals (15 stroke survivors and 15 healthy-matched controls) were included. The following biomechanical characteristics were determined: peak of trunk forward flexion and time until the peak of trunk forward flexion, total duration, phase I (sit-to-stand: time spent from the beginning to seat-off; stand-to-sit: time spent from the beginning to seat-on) and II durations (sit-to-stand: time spent from seat-off to the end of the task; stand-to-sit: time spent from the seat-on to the end of the task). Two-way repeated measures ANOVA was used (α = 5%).

RESULTS

The maximum angle of trunk forward flexion and time spent until the maximum angle of trunk forward flexion in both tasks were significantly higher in stroke survivors. For both groups and speeds, phase I duration and peak of trunk forward flexion of the stand-to-sit were significantly higher than that of the sit-to-stand (11.41≤F ≤ 33.60; 0.001 ≤ p ≤ 0.002) and, phase II duration was significantly higher during the sit-to-stand than that of the stand-to-sit (21.27 ≤ F ≤ 65.10; p ≤ 0.001).

CONCLUSIONS

These results confirm specific trunk biomechanical characteristics between sit-to-stand and stand-to-sit in stroke survivors and healthy-matched controls.

30-Second Chair Stand and 5-Times Sit-to-Stand Tests Are Interesting Tools for Assessing Disability and Ability to Ambulate among Patients with Multiple Sclerosis

Multiple Sclerosis (MS) is a demyelinating and chronic disease with variable neurological symptoms. There are different scales that score the level of disability, but only few papers have taken into consideration the 5-times sit-to-stand (5STS) test and the 30 s chair stand test (30CST), which are valid and easily obtainable indicators of other neurological diseases. The aim of our research is to verify the validity, reproducibility, and responsiveness of these tests. Patients afflicted with MS were enrolled in the AISM outpatient facility. The inclusion criterion was an EDSS score less than 6.5. We performed the 5STS, 30CST, and timed 25-foot walk (T25-FW) tests and recorded EDSS scores in the first evaluation. Then, we recorded the performance after 5 days (conducted by a second blind operator to ensure test-retest reproducibility), and the last evaluation was made after 12 sessions of physiotherapy. We recruited 38 patients diagnosed with MS. The results show significant data regarding validity, reproducibility, and responsiveness for both scales. The data argue in favor of adding these tests to the relevant clinical assessments. These two tests are simple, reliable, and easy to administer, and the data confirm that they can be included in the evaluation of patients with MS.

An Overview of Physical Exercise Program Protocols and Effects on the Physical Function in Multiple Sclerosis: An Umbrella Review

Multiple sclerosis is a disease that concerns a growing number of people, especially females. There are different interventions proposed for this population, and physical activity is one of them. A proper and well-structured physical activity program can be a cheap, feasible, and practical instrument to help this population improve their quality of life. Consequently, the present study aimed to analyze, through an umbrella review, published articles to evaluate the protocols and the effect of intervention on different types of multiple sclerosis and eventually to propose a standardized intervention for this population. Systematic reviews and meta-analyses of randomized controlled trials on multiple sclerosis and physical activity effects were searched for on the electronic databases PubMed, Web of Science, and Scopus up to 22 December 2022. The quality of the studies included was determined and the results were narratively analyzed. The included studies present heterogeneity in the population, in the study design and protocols, and in the outcomes evaluated. Most of the studies detected positive outcomes on the physical function of people with multiple sclerosis. This study highlights the necessity of future studies on a population with similar characteristics, adopting similar protocols to evaluate their feasibility and validity to make physical intervention prescribed as a medicine.

Validity of the 30-Second Sit-to-Stand test as a measure of lower extremity function in persons with multiple sclerosis: Preliminary evidence

BACKGROUND

The 30-Second Sit-To-Stand (30SSTS) is a quick, inexpensive, safe, and widely used clinical measure of lower extremity function. To date, there is limited evidence regarding the use of 30SSTS in multiple sclerosis (MS). The purpose of this study was to examine the construct validity of the 30SSTS test in persons with MS compared with non-MS healthy controls.

METHODS

Twenty ambulatory persons with MS and twenty age- and sex-matched healthy controls completed the 30SSTS, Timed 25-Foot Walk (T25FW), Timed Up and Go (TUG), Six-Minute Walk (6MW), and Godin Leisure-Time Exercise Questionnaire (GLTEQ). Persons with MS also completed the Patient Determined Disease Steps (PDDS) and 12-item MS Walking Scale (MSWS-12).

RESULTS

Persons with MS had significantly worse performance on the TUG (mean difference [95% confidence interval] = 1.4 [0.5, 2.3] sec) and 6MW (-259.2 [-450.8, -67.6] ft), but not on the 30SSTS (-1.6 [-1.5, 4.6] reps) and T25FW (-0.59 [-0.1, 1.2] ft/sec) compared with controls. There were significant moderate-to-strong correlations between the 30SSTS with T25FW, TUG, and 6MW scores in persons with MS (r = 0.48, -0.65 and 0.61, respectively), whereas the 30SSTS was only significantly associated with 6MW scores (r = 0.43) in controls. The 30SSTS was negatively associated with MS-related walking disability assessed by the PDDS and MSWS-12 (r_s = -0.52 and -0.64, respectively), but was not significantly associated with the GLTEQ in MS and controls (r = 0.30 and 0.17, respectively).

CONCLUSION

This study provides initial support for the construct validity of the 30SSTS as a measure of lower extremity function in persons with MS. Our findings warrant the inclusion of the 30SSTS as a feasible and valid measure of physical function in clinical research and practice involving persons with MS.

Trunk and lower extremity biomechanics during sit-to-stand after stroke: A systematic review

OBJECTIVES

This systematic review aimed to pool available evidence of differences in trunk and lower extremity biomechanics during the different phases of a sit-to-stand (STS) task between persons with stroke and to healthy controls.

METHODS

Four electronic databases (Medline, Web of Science, EMBASE, and Cochrane Library) were systematically searched up to, and including, December 2021. Studies were included if they investigated kinematic, kinetic and/or electromyographic outcome measures of adults with stroke during STS and compared results with healthy controls. Data from eligible studies were categorized according to STS subphases if reported (Phase I: Movement onset to seat-off; Seat-off; Phase II: Seat-off to movement termination; Whole task [if no subtasks reported]). The Newcastle-Ottawa Scale was used to assess risk of bias.

RESULTS

Twenty-one studies were included in this systematic review. Methodological quality ranged from 13% to 75%; mean score was 55%. The findings of this systematic review suggest that after stroke, people rise to stand (phase I) with increased lateral trunk flexion and displacement of the center of pressure (COP) towards the non-paretic side, decreased anterior pelvic tilt, decreased hip flexion and altered timing of lower limb muscle activation. In addition, during phase II, lateral pelvic translation and weight distribution asymmetry was increased, knee extension velocity was decreased and delayed, stabilization was decreased and COP velocity was increased compared with healthy subjects.

CONCLUSIONS

This systematic review clearly showed changes in kinematics, kinetics and muscle recruitment after stroke, with differences between the different phases of STS. Therapeutic interventions should focus on subphases of this functional task to optimize performance in daily living.

Functional Performance, Leg Muscle Strength, and Core Muscle Endurance in Multiple Sclerosis Patients With Mild Disability: A Cross-Sectional Study

This study aimed to investigate the relationship of sit-to-stand and walking performance with leg muscle strength and core muscle endurance in people with multiple sclerosis (PwMS) with mild disabilities. In this study, 49 PwMS (Expanded Disability Status Scale score = 1.59 ± 0.79) and 26 healthy controls were enrolled. The functional performances, including sit-to-stand and walking performances, were evaluated with the five-repetition sit-to-stand test, timed up and go test, and 6-min walking test. The PwMS finished significantly slower five-repetition sit-to-stand, timed up and go, and 6-min walking test than the healthy controls. In addition, the significant contributors were the weakest trunk lateral flexor endurance for five-repetition sit-to-stand; the Expanded Disability Status Scale score, and the weakest hip adductor muscle for timed up and go; the weakest hip extensor muscles strength for 6-min walking test. The functional performances in PwMS, even with mild disabilities, were lower compared with healthy controls. Decreases in both leg muscle strength and core muscle endurance are associated with lower functional performance in PwMS.

Gait assessment in shaped pathways: The test-retest reliability and concurrent validity of the figure of eight test and L test in multiple sclerosis patients without mobility aids

PURPOSE

To our knowledge, no other studies have demonstrated the reliability and validity of the Figure of Eight Walking Test (F8WT) and L Test in patients with multiple sclerosis (MS). The aim of the study was to prove the test-retest reliability and concurrent validity of the F8WT and L Test in patients with MS.

METHODS

A cross-sectional study was conducted with 52 patients with MS. A clinical neurologist evaluated patients by Expanded Disability Status Scale (EDSS). Participants completed the F8WT, L Test, Timed Up and Go Test (TUG), and Timed 25-Foot Walk Test (T25FW) in the first assessment session. Then, the F8WT and L Test was retested one hour later. The same evaluator completed all of the assessments.

RESULTS

The ICC of both tests were excellent (ICC_F8WT: 0.972, ICC_{L Test}: 0.986). F8WT and L test measurement did not show a systematic bias and were within the agreement limits. The Standard Error of Measurement (SEM₉₅) and Minimal Detectable Change (MDC₉₅) values of the F8WT was 0.58 and 1.60, respectively. Besides, L Test's SEM₉₅ and MDC₉₅ were 0.59 and 1.63. The correlation between F8WT with TUG, T25FW and EDSS was 0.849, 0.810 and 0.453. On the other hand, the L test's correlation coefficient with TUG, T25FW and EDSS 0.682, 0.706 and 0.535, respectively (p < 0.01). Individuals with "EDSS ≤ 1″ had statistically significantly better L-test and F8WT scores than those with "EDSS: 1 to 4.5″ (p < 0.01).

CONCLUSION

F8WT and L Test is a valid and reliable physical performance test in MS patients without mobility aids. Both tests demonstrate advanced gait assessment in L and 8 shaped pathways to provide more comprehensive evaluation than horizontal pathways.

A Framework for Movement Analysis of Tasks: Recommendations From the Academy of Neurologic Physical Therapy's Movement System Task Force

The American Physical Therapy Association's Vision Statement of 2013 asserts that physical therapists optimize movement in order to improve the human experience. In accordance with this vision, physical therapists strive to be recognized as experts in movement analysis. However, there continues to be no accepted method to conduct movement analysis, nor an agreement of key terminology to describe movement observations. As a result, the Academy of Neurologic Physical Therapy organized a task force that was charged with advancing the state of practice with respect to these issues, including the development of a proposed method for movement analysis of tasks. This paper presents the work of the Task Force, which includes (1) development of a method for conducting movement analysis within the context of the movement continuum during 6 core tasks (sitting, sit to stand, standing, walking, step up/down, and reach/grasp/manipulate); (2) glossary of movement constructs that can provide a common language for movement analysis across a range of tasks: symmetry, speed, amplitude, alignment, verticality, stability, smoothness, sequencing, timing, accuracy, and symptom provocation; and (3) recommendations for task and environmental variations that can be systematically applied. The expectation is that this systematic framework and accompanying terminology will be easily adapted to additional patient or client-specific tasks, contribute to development of movement system diagnostic labels, and ultimately improve consistency across patient/client examination, evaluation, and intervention for the physical therapy profession. Next steps should include validation of this framework across patient/client groups and settings.

The clinical correlates of the chair sit to stand performance in people with multiple sclerosis

Objective: This study aimed to evaluate the motor and non-motor factors associated with sit-to-stand performance in people with Multiple Sclerosis (PwMS). Design: Observational cross-sectional study. Subjects: A total of 88 individuals with MS participated in this study. Main Measures: Standing performance was measured using the five-times-sit-to-stand test (FTSTS). The Berg Balance Scale to assess balance, the 10-Meter Walking Test (10-MWT) was used to assess walking speed; the Patient Determined Disease Steps (PDDS) was used to assess disability level. Furthermore, Brief International Cognitive Assessment for MS (BICAMS) was used to assess cognitive status, Hospital Anxiety and Depression scale (HADS) to assess depression and anxiety, and the Modified Fatigue Impact scale (MFIS) to evaluate fatigue. Spearman correlation coefficient was used to determine the relationship between all these variables and the FTSTS. Furthermore, multiple linear regression was conducted to determine predictive factors of the FTSTS. Results: FTSTS score was correlated significantly with BBS, PDDS, BICAMS, 10-MWT and MFIS (r ranged from 0.3 to 0.52; P < .05). However, there was no significant correlation observed between the FTSTS and HADS-depression or HADS-anxiety. Considering the multiple regression analysis, the following factors were significantly predictive of the FTSTS: 10-MWT, MFIS and the BICAMS-z score (R²: 0.433, P < .0001). Conclusion: The study concludes that sit to stand is multifactorial and is potentially associated with walking speed, cognitive function and fatigue. These factors should be considered by healthcare professionals in interpreting the sit-to-stand performance of PwMS and in designing rehabilitation interventions.

Functional muscle balance assessment in multiple sclerosis

BACKGROUND

Chronic demyelinisation in multiple sclerosis (MS) involves changes in the muscle structure and development of motor disorders.

OBJECTIVE

The aim of this research is to assess the muscle balance of thigh muscle in MS using a noninvasive method, to have information about the muscle status prior to the rehabilitation and to prevent muscle damage.

METHODS

The studied group consisted of 20 patients: 9 men and 11 women, with a mean age of 42 years. The patients were diagnosed with MS in different stages. The clinical evaluation included clinical examination, neurological examination, functional evaluation by using the Hamilton score, the activity daily living (ADL) scale and the Kurtze (EDSS) scale. For the muscle assessment we used tensiomyography (TMG), an evaluation method for the functional potential of the muscle, depending on the muscle composition. The TMG parameters are displacement (Dm), contraction time (Tc) and sustain time (Ts) for biceps femoris (mBF) and rectus femoris (mRF).

RESULTS

The value of Dm shows low values for both studied muscle groups, but closer to the normal value for mBF. The average normal Tc values for mBF are 30.25 ± 3.5 ms and 32.83 ± 4.5 for mRF. The values are low values for mRF and high for mBF. The normal values of Ts are not standard values and can be compared healthy individuals' values. These parameters could monitor the evolution and in our research have lower values for mRF. In the thigh, there was a significant difference in the Dm values, with higher values in mBF and also with higher values in the right lower limb. Analyzing the Ts results, we noticed a difference between the two muscle groups with a significant reduction in mRF, showing the inability to achieve anterior-posterior symmetry and the tendency to develop type I fibers at mBF level.

CONCLUSIONS

Our study showed the presence of a structural and functional asymmetry explained by the tendency of increasing the tonus at mRF level in order to compensate the knee stability. We noticed a decrease in Tc value at the mRF level, but close to the value of the two lower limbs. TMG analysis revealed the asymmetry of the muscle composition at the level of the antagonist muscle groups of the thigh, with an increase in the percentage of type II fibers in the previous group, which became hyperton, and a decrease in the percentage of type I fibers in the posterior group.

Effect of a Combined Program of Strength and Dual Cognitive-Motor Tasks in Multiple Sclerosis Subjects

This study investigated the effects of a 24-week combined training program (CTP) based on strength exercises and cognitive–motor tasks performed concurrently in participants with multiple sclerosis. A randomized, controlled intervention study was carried out. In total, 31 subjects with a confirmed diagnosis of multiple sclerosis (14 men and 17 women) were stratified and randomized into an intervention group (17 subjects) and a control group (14 subjects). The intervention group completed three weekly training sessions for 24 weeks, while the control group pursued their normal daily activities. In this program, cognitive–motor tasks were completed at once (dual tasking). A 3D photogrammetry connected to a selective attention system designed for dual tasking while walking was used. Ground reaction forces were measured using two force plates, one for sit-to-stand testing, while the other was used for static force measurement. Postural equilibrium was examined using a stabilometric plate based for Romberg test assessment. The 24-week training program for multiple sclerosis patients improved their static peak force by 11% (p < 0 .05), their rate of force development by 36% (p < 0.05), and their balance (p < 0.05). Performance in daily activities such as walking or sitting-to-standing improved significantly in multiple sclerosis participants. CTP training was effective in reducing the dual-task costs of step length (48%) and walking velocity (54%), as compared to a matched control group.

Research on lower extremity health in patients with multiple sclerosis: a systematic scoping review

Background

Multiple sclerosis (MS) often affects ambulation and the function of the lower limbs. However, little is known about how much research has been conducted on lower extremity health in patients with MS.

Objective

To analyse empirical studies and their evidence on lower extremity health in patients with MS, in order to identify the need for future studies in key areas.

Methods

A systematic scoping review was conducted. A literature search of Medline (PubMed), CINAHL (EBSCO) and the Cochrane Library databases was performed. The search covered the period up to 15 January 2020 from the earliest records available. This led to the inclusion of 42 empirical articles. The data were analysed using content analysis and quantification techniques.

Results

The research on lower extremity health focused primarily on two main areas: gait and lower extremity muscle strength. Lower extremity health was assessed using a variety of methods, most of which consisted of objective physical tests and gait analysis. Patients with MS had many problems with the health of their lower extremities, which manifested in walking difficulties, balance problems, muscle weaknesses and spasticity. In the feet, pes cavus, claw toes, oedema and altered foot sensation were common.

Conclusions

MS affects lower limb and foot health, and these problems can affect patients’ daily lives. However, the extent of these problems is poorly understood, partly due to the dearth of research on lower limb and foot health. Therefore, further research is warranted in order to better understand the impact of MS on foot and lower limb health in everyday life.

Metrics extracted from a single wearable sensor during sit-stand transitions relate to mobility impairment and fall risk in people with multiple sclerosis

BACKGROUND

Approximately half of the 2.3 million people with multiple sclerosis (PwMS) will fall in any three-month period. Currently clinicians rely on self-report measures or simple functional assessments, administered at discrete time points, to assess fall risk. Wearable inertial sensors are a promising technology for increasing the sensitivity of clinical assessments to accurately predict fall risk, but current accelerometer-based approaches are limited.

RESEARCH QUESTION

Will metrics derived from wearable accelerometers during a 30-second chair stand test (30CST) correlate with clinical measures of disease severity, balance confidence and fatigue in PwMS, and can these metrics be used to accurately discriminate fallers from non-fallers?

METHODS

Thirty-eight PwMS (21 fallers) completed self-report outcome measures then performed the 30CST while triaxial acceleration data were collected from inertial sensors adhered to the thigh and chest. Accelerometer metrics were derived for the sit-to-stand and stand-to-sit transitions and relationships with clinical metrics were assessed. Finally, the metrics were used to develop a logistic regression model to classify fall status.

RESULTS

Accelerometer-derived metrics were significantly associated with multiple clinical metrics that capture disease severity, balance confidence and fatigue. Performance of a logistic regression for classifying fall status was enhanced by including accelerometer features (accuracy 74%, AUC 0.78) compared to the standard of care (accuracy 68%, AUC 0.74) or patient reported outcomes (accuracy 71%, AUC 0.75).

SIGNIFICANCE

Accelerometer derived metrics were associated with clinically relevant measures of disease severity, fatigue and balance confidence during a balance challenging task. Inertial sensors could feasibly be utilized to enhance the accuracy of functional assessments to identify fall risk in PwMS. Simplicity of these accelerometer-based metrics could facilitate deployment for community-based monitoring.

Knee Joint Biomechanics in Physiological Conditions and How Pathologies Can Affect It: A Systematic Review

The knee joint, as the main lower limb motor joint, is the most vulnerable and susceptible joint. The knee injuries considerably impact the normal living ability and mental health of patients. Understanding the biomechanics of a normal and diseased knee joint is in urgent need for designing knee assistive devices and optimizing a rehabilitation exercise program. In this paper, we systematically searched electronic databases (from 2000 to November 2019) including ScienceDirect, Web of Science, PubMed, Google Scholar, and IEEE/IET Electronic Library for potentially relevant articles. After duplicates were removed and inclusion criteria applied to the titles, abstracts, and full text, 138 articles remained for review. The selected articles were divided into two groups to be analyzed. Firstly, the real movement of a normal knee joint and the normal knee biomechanics of four kinds of daily motions in the sagittal and coronal planes, which include normal walking, running, stair climbing, and sit-to-stand, were discussed and analyzed. Secondly, an overview of the current knowledge on the movement biomechanical effects of common knee musculoskeletal disorders and knee neurological disorders were provided. Finally, a discussion of the existing problems in the current studies and some recommendation for future research were presented. In general, this review reveals that there is no clear assessment about the biomechanics of normal and diseased knee joints at the current state of the art. The biomechanics properties could be significantly affected by knee musculoskeletal or neurological disorders. Deeper understanding of the biomechanics of the normal and diseased knee joint will still be an urgent need in the future.

Five-repetition sit-to-Stand test among patients post-stroke and healthy-matched controls: the use of different chair types and number of trials

Background: In 2018, the American Physical Therapy Association (APTA) published a clinical guideline for adults with neurological conditions, which included recommendations for the Five-Repetition Sit-to-Stand test (5STSt). According to the APTA, a standard-height chair should be used, but there is no recommendation regarding seat depth. In addition, the APTA recommended the use of one trial of the test, based on expert opinion.Objectives: (1) Compare the 5STSt scores of patients post-stroke and healthy-matched controls using two types of chairs (one standardized and one adjusted to the individual's anthropometric characteristics); and (2) Verify whether different numbers of trial affect the 5STSt scores.Methods: Eighteen patients post-stroke and 18 healthy-matched controls performed three trials of the 5STSt for each type of chair. ANOVA was used for analysis (α = 0.05).Results: No significant interaction between groups and chairs was found. Patients post-stroke showed worsened performances in 5STSt when using both chairs compared to the healthy controls (p = .001). In both groups, the 5STSt scores were lower when using a standardized chair than an adjusted chair (p < .003) and different numbers of trials provided similar 5STSt scores (0.44 ≤ p ≤ 0.98).Conclusion: The 5STSt scores were affected by the physical characteristics of the chair, and an adjusted chair should be used. The APTA recommendation for one trial of the 5STSt is supported by the present results.

The importance of lower-extremity muscle strength for lower-limb functional capacity in multiple sclerosis: Systematic review

BACKGROUND

Lower-limb functional capacity is impaired in most people with multiple sclerosis (PwMS). Reductions in lower-extremity muscle mechanical function (e.g., muscle strength) appear to have critical implications for lower-limb functional capacity. However, no review has summarized the current knowledge about the importance of muscle strength for functional tasks in PwMS. Expanding the current knowledge would advance the design of both clinical and research interventions aiming to improve functional capacity in PwMS.

OBJECTIVES

(1) To identify studies that measured lower-extremity muscle mechanical function and lower-limb functional capacity outcomes in PwMS, and (2) to map associations between muscle strength and functional capacity.

METHODS

This review was based on a literature search (databases: PubMed, Embase). Included studies had to report data on lower-extremity muscle mechanical function and lower-limb functional capacity outcomes in PwMS. The associations between muscle strength and functional capacity were analyzed by using the reported correlation coefficients (R) recalculated to the determination coefficient R². Randomized trials and observational studies were included.

RESULTS

A total of 59 articles were reviewed; 17 (773 participants) reported associations between muscle strength and functional capacity. Lower-extremity muscle mechanical function explained a significant part of the variance in most lower-limb functional capacity tests (approximately 20-30%). This was particularly evident in muscle strength from the weakest leg. Muscle strength was predominantly tested on knee extensors and knee flexors by using isokinetic dynamometry during maximal isometric (0°/s) and dynamic (30-60°/s) contractions. Walking tests such as the timed 25-Foot Walk Test and 10-Min, 2-Min and 6-Min Walk Test were the most frequently performed functional capacity tests.

CONCLUSIONS

In PwMS, muscle strength of particularly the weakest limb explains 20% to 30% of the variance across a number of lower-limb functional capacity tests. Thus, exercise programs should focus on increasing lower-extremity muscle mechanical function in PwMS and minimizing strength asymmetry between limbs.

Electromyographic activity and kinematics of sit-to-stand in individuals with muscle disease

OBJECTIVE

The aim of this study was to compare activation levels of rectus femoris, biceps femoris, tibialis anterior, and soleus muscles and biomechanical properties of individuals with muscle disease and healthy individuals during sit-to-stand.

METHODS

Fifteen patients (11 muscular dystrophy, 4 myopathy) and 15 healthy individuals were included in the study. A Noraxon superficial electromyography device and high-speed cameras were used to evaluate muscle activations and biomechanical properties.

RESULTS

There was a difference between the activation levels of bilateral rectus femoris, tibialis anterior, soleus, and right biceps femoris of patients and healthy subjects (p < 0.05). When groups were compared in terms of biomechanical properties, there was no difference in the range of motion during sit-to-stand (p > 0.05), but there was a difference in phase 1: flexion momentum phase, phase 3: extension phase, phase 4: stabilization phase, and total time of sit-to-stand (p < 0.05).

CONCLUSION

We observed that individuals with muscle disease are able to stand up in a similar sit-to-stand pattern to healthy individuals with longer duration and higher muscle activation levels. Prolonged high muscle activation during functional activities may cause fatigue and muscle destruction in patients. For this reason, planning of exercise programs for appropriate muscles and phases will enable the patients to perform the activity of sit-to-stand more easily. Thus, patients will become more functional and independent in their daily lives with less effort.

Biomechanical analysis of the timed up-and-go (TUG) test in children with and without Down syndrome

BACKGROUND

The timed up-and-go (TUG) test consists of multiple functional activities of daily living performed in a sequence, with the goal to complete the test as quickly as possible. Considering children with Down syndrome (DS) have been shown to take longer to complete the TUG test, it is imperative to identify which tasks are problematic for this population in order to individualize physical interventions.

RESEARCH QUESTION

Is the biomechanical pattern of each functional task during the TUG test different between children with DS and typically developing (TD) children?

METHODS

Thirteen children with DS and thirteen TD children aged 5-11 years old completed the TUG test. Kinematic data was captured using a Vicon motion capture system. We visually coded the TUG test into five phases: sit-to-stand, walk-out, turn-around, walk-in, and stand-to-sit. We focused on the center-of-mass (COM) movement in the sit-to-stand phase, spatiotemporal parameters in the walk-out phase, and intersegmental coordination in the turn-around phase.

RESULTS AND SIGNIFICANCE

Children with DS took longer to complete the entire test, as well as each of the five phases. During the sit-to-stand phase, children with DS produced smaller peak vertical COM velocity, medial-lateral COM excursion, and peak knee and hip extension velocity compared to TD peers. Children with DS walked at a slower velocity during the walk-out phase. Both groups demonstrated a similar intersegmental coordination pattern between the head, thorax, and pelvis during the turn-around phase although children with DS had slower average and peak angular velocity at the head, thorax, and pelvis. Our results suggest that children with DS were less able to anticipate transitioning between motor tasks and took longer to initiate motor tasks. Our TUG analysis provides the detailed insights to help evaluate individual motor tasks as well as the transition from one task to another for clinical populations.

Are static and functional balance abilities related in individuals with Multiple Sclerosis?

BACKGROUND

In people with Multiple Sclerosis (pwMS), balance assessment is essential in estimating the risk of falls, monitoring disease progression and verifying the effectiveness of rehabilitative treatment. Clinical tools and instrumental techniques are available for testing static and dynamic balance, but the relationship between such abilities is still not clear. Having information about this link would be important in properly planning the type and number of tests to administer.

METHODS

One hundred and six pwMS (Expanded Disability Status Scale, EDSS 0-6.5) stratified in three sub-groups (Class 1 EDSS 0-1.5, Class 2 EDSS 2-4 and Class 3 EDSS 4.5-6.5) and 42 healthy controls (HC) participated in the study. All underwent static posturography and instrumented Timed-Up-and-Go (TUG) performed using a wearable inertial sensor. Raw data were processed to extract postural sway features, overall duration of TUG and its main sub-phases (i.e. sit-to-stand, 180° turns and stand-to-sit).

RESULTS

All sway parameters of pwMS of Classes 2 and 3, as well as total TUG duration and time necessary to perform 180° turns, were found significantly higher than HC and Class 1 participants. However, poor correlations were found between sway and TUG parameters. When pwMS are grouped, small/moderate correlations (in the range 0.20-0.41) were found between all sway parameters and total TUG duration.

CONCLUSIONS

Static and dynamic balance in pwMS appear scarcely correlated, although both worsen as disability increases. This implies that they should be separately assessed using specific tests to have a complete view of postural control performance in MS.