Activation timing patterns of the abdominal and leg muscles during the sit-to-stand movement in individuals with chronic hemiparetic stroke

Perceived Discomfort, Neck Kinematics, and Muscular Activity During Smartphone Usage: A Comparative Study

OBJECTIVE

The present study aims to evaluate the effects of posture, task, and handgrip style on discomfort, neck kinematics, and concomitant muscular activity when using a smartphone (SP).

BACKGROUND

Along with the popularity of smartphones, musculoskeletal disorders have become prevalent among smartphone users. However, comprehensive aspects of discomfort, kinematics, and electromyographic responses across various conditions remain to be investigated.

METHOD

Twenty-four young smartphone users performed typing, video watching, and reading tasks while holding the smartphone both with one hand and with two hands while either sitting or standing. Neck kinematics and muscular activities were simultaneously recorded.

RESULTS

Working with SPs led to higher discomfort in the neck (p = 0.01), lower back (p = 0.01), and shoulder (p = 0.04) while sitting as compared to standing. Sitting was associated with greater neck flexion and more minor lateral bending for all tasks and grip styles (p < 0.05). Electromyographic analysis indicated significant differences between sitting and standing, with alterations being dependent on the test condition. Moreover, neck kinematics and muscular activities significantly differed based on the task nature, handgrip, and interactions.

CONCLUSION

This study highlights the risk of using smartphones in increased neck angle flexion and muscular activities fatigue. Thus, posture and handgrip should be considered while using SPs. As each test condition affects a specific dependent variable, a holistic approach is required to evaluate the responses of SP users' musculoskeletal systems.

APPLICATION

Results can be applied to develop guidelines for musculoskeletal disorders/discomfort prevention among SP users, especially with the rise of smartphone use during the COVID-19 pandemic.

Developmentally delayed children with different muscle tone have different muscle activity and acceleration during sit-to-stand

Developmental delays cover a wide range, with different movement characteristics occurring depending on differences in muscle tone. We aimed to investigate muscle activity and acceleration during sit-to-stand in developmentally delayed (DD) children with different muscle tones. Forty participants were divided into three groups: typically developing (TD) children (n=18), DD children with hypertonia (n=12), and DD children with hypotonia (n=10). Electromyography was used to measure muscle activity and BTS G-Walk was used to measure acceleration. As a result, the activities of the rectus abdominal muscle and quadriceps muscle were lower in DD children with hypertonia than in TD children (P<0.05). The activity of the tibialis anterior muscle was higher in DD children with hypotonia than in TD children (P<0.05). The trunk angle was greater in DD children with hypotonia than in TD children (P<0.05), and vertical acceleration was lower in DD children with hypertonia than in TD children (P<0.05). Based on these differences, we will be able to provide intervention programs appropriate for the characteristics of DD children with different muscle tone.

Analysis of inter-joint coordination during the sit-to-stand and stand-to-sit tasks in stroke patients with hemiplegia

BACKGROUND

Inter-joint coordination is an important factor affecting postural stability, and its variability increases after fatigue. This study aimed to investigate the coordination pattern of lower limb joints during the sit-to-stand (Si-St) and stand-to-sit (St-Si) tasks in stroke patients and explore the influence of duration on inter-joint coordination.

METHODS

Thirteen stroke hemiplegia patients (five with left paretic and eight right paretic) and thirteen age-matched healthy subjects were recruited. The Si-St and St-Si tasks were performed while each subject's joint kinematics were recorded using a three-dimensional motion capture system. Sagittal joint angles of the bilateral hip, knee and ankle joints as well as the movement duration were extracted. The angle-angle diagrams for the hip-knee, hip-ankle and knee-ankle joint were plotted to assess the inter-joint coordination. The inter-joint coordination was quantified using geometric characteristics of the angle-angle diagrams, including perimeter, area and dimensionless ratio. The coefficient of variation (CV) was performed to compare variability of the coordination parameters.

RESULTS

There were no significant differences in the perimeter, area and dimensionless ratio values of the bilateral hip-knee, hip-ankle and knee-ankle inter-joints during Si-St and St-Si tasks in the stroke group. The perimeter values of bilateral hip-knee and knee-ankle inter-joints in the stroke group were lower (P<0.05) than in the healthy group during Si-St and St-Si tasks. Although no significant bilateral differences were found, the inter-joint coordination in stroke patients decreased with the increased movement duration of both Si-St and St-Si tasks. Additionally, the CV of the hip-knee inter-joint area during the Si-St task in the stroke group was less than (P<0.05) that in the healthy group.

CONCLUSION

Stroke patients exhibit different inter-joint coordination patterns than healthy controls during the Si-St and St-Si tasks. The duration affects joint coordination, and inter-joint coordination is limited on the hemiplegic side joint pairs, which may lead to inconsistency in the rhythm of the left and right leg inter-joint movements and increase the risk of falls. These findings provide new insights into motor control rehabilitation strategies and may help planning targeted interventions for stoke patients with hemiplegia.

Effects of visual-motor illusions with different visual stimuli on the sit-to-stand of people with hemiplegia following stroke: A randomized crossover controlled trial

BACKGROUND

The objective of this study was to determine the effects of different visual stimuli during visual-motor illusion on sit-to-stand in people with hemiplegia following stroke.

METHODS

This was a randomized crossover controlled trial. Twenty people with hemiplegia following stroke were randomly divided into groups. The video images used for visual-motor illusion were ankle dorsiflexion without resistance (standard visual-motor illusion [standard illusion]) and maximum effort dorsiflexion with resistance (power visual-motor illusion [power illusion]). People with hemiplegia following stroke underwent both illusion interventions with a 1-week washout period in between; group A started with the standard illusion intervention and group B started with the power illusion intervention. Outcomes included the sit-to-stand duration, maximum weight-bearing value, trunk movement during sit-to-stand, ankle joint movement during sit-to-stand, and active ankle dorsiflexion movement on the paralyzed side.

RESULTS

The angular velocity of the trunk and ankle joints increased significantly during sit-to-stand, and sit-to-stand duration decreased significantly in response only to power illusion. In addition, the change in angular velocity of active ankle dorsiflexion was significantly greater in response to power illusion than was the change in response to standard illusion.

CONCLUSION

Power illusion induces a greater improvement in paralyzed ankle dorsiflexion function than standard illusion, resulting in shorter sit-to-stand duration.

Gluteus Maximus Muscle Activation Characteristics During a Chair-Rise in Adults With Chronic Stroke

BACKGROUND AND PURPOSE

A successful chair-rise is an important indicator of functional independence post-stroke. Lower extremity electromyographic analyses provide a basis for muscle activation from which clinical intervention protocols may be derived. Gluteus maximus activation during the chair-rise has not been thoroughly researched in the chronic stroke population. This study investigated the magnitude and onset of gluteus maximus activation during the chair-rise comparing adults post-stroke with healthy controls.

METHODS

In this cross-sectional study, adults with chronic stroke (n = 12) and healthy controls (n = 12) completed 4 natural-speed chair-rise trials. Magnitude and onset of bilateral gluteus maximus activation were measured during the movement with secondary comparative data from biceps femoris and vastus lateralis muscles. Kinetic and kinematic measurements were used to quantify chair-rise phases and movement cycle duration.

RESULTS

Significant decreases in paretic ( P = 0.002), and nonparetic ( P = 0.001) gluteus maximus magnitudes were noted post-stroke compared with ipsilateral extremities of healthy adults. Significant gluteus maximus onset delays were noted in paretic extremities compared with nonparetic extremities post-stroke ( P = 0.009) that were not apparent in comparative muscles. Similar onset times were noted when comparing the paretic extremity post-stroke to the ipsilateral extremity of healthy controls ( P = 0.714) despite prolonged movement cycle durations in those with chronic stroke ( P = 0.001). No onset delays were evident in the biceps femoris ( P = 0.72) or vastus lateralis ( P = 0.338) muscles.

DISCUSSION AND CONCLUSIONS

Despite apparent unilateral muscle weakness post-stroke, bilateral decreases in gluteus maximus activation magnitudes and compounding onset deficits of the paretic extremity were observed during chair-rising. Further research is needed to determine whether interventions maximizing bilateral activation magnitudes and improving temporal activation congruency during chair-rising will carry over to functional gainsVideo Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A387 ).

Effects and Adaptation of Visual-Motor Illusion Using Different Visual Stimuli on Improving Ankle Joint Paralysis of Stroke Survivors—A Randomized Crossover Controlled Trial

Visual-motor illusion (VMI) is an intervention to induce kinesthetic sensation from visual stimuli. We aimed to compare the effects of VMI of different visual stimuli on the paralyzed side ankle joint of stroke hemiplegic patients (hemiplegic patients) and to clarify their indication. We applied two types of VMI images of ankle dorsiflexion: ankle dorsiflexion without resistance (standard VMI (S-VMI)) and maximum effort dorsiflexion with resistance (power VMI (P-VMI)). Twenty-two hemiplegic patients were divided into two groups: Group A, which received S-VMI first and P-VMI one week later (n = 11), and Group B, which received P-VMI first and S-VMI one week later (n = 11). Immediate effects were evaluated. Outcomes were the dorsiflexion angle and angular velocity, degree of sense of agency (SoA), and sense of ownership. Patient’s characteristics of cognitive flexibility were assessed using the Trail making test-B (TMT-B). Fugl-Meyer assessment and the Composite-Spasticity-Scale were also assessed. P-VMI was significantly higher than S-VMI in SoA and dorsiflexion angular velocity. Additionally, the degree of improvement in dorsiflexion function with P-VMI was related to TMT-B and degree of muscle tone. Therefore, P-VMI improves ankle function in hemiplegic patients more than S-VMI but should be performed with cognitive flexibility and degree of muscle tone in mind.

Postural Maintenance Is Associated With Walking Ability in People Receiving Acute Rehabilitation After a Stroke

OBJECTIVES

The Postural Assessment Scale for Stroke Patients (PASS) assesses the ability of people post stroke to maintain or change a given posture from lying to standing, and the items on which people with different walking status perform differently may suggest potential interventions. The purpose of this study was to (1) examine the association of PASS scores at admission for acute rehabilitation with walking status at admission and 3 months post stroke (3 M), and (2) identify PASS items that discriminate walking status.

METHODS

In this prospective observational study, 93 people post stroke were assessed with the PASS and a 2.44-m gait speed test at admission, with walking status assessed by telephone interview at 3 M. Those who could walk over a 2.44-m distance without the assistance of a walking aid or another person were considered to be independent in walking; others were considered to be dependent. Those who were dependent at admission were divided into the "regained independence" and "remained dependent" groups based on their status at 3 M. The association of the PASS at admission with 3 levels of walking status (independent at admission, regained independence, and remained dependent) was examined using the Kruskal-Wallis test. For those dependent at admission, the association of PASS score at admission with walking status at 3 M was examined using logistic regression and receiver operating curve analysis.

RESULTS

PASS scores at admission differed significantly across the 3 walking status groups and were significantly associated with walking status at 3 M (odds ratio = 0.864; 95% CI = 0.798-0.935) over and above length of stay. People post stroke who were dependent at admission and had PASS scores ≥22 were more likely to regain independence at 3 M. Nine PASS items differed among the 3 groups.

CONCLUSIONS

PASS score is significantly associated with walking status at admission and at 3 M. The identified 9 items suggest possible interventions for acute rehabilitation.

IMPACT

This study identified 9 PASS items that could guide clinicians in selecting interventions for acute rehabilitation.

Effects of kinesthetic illusion induced by visual stimulation on the ankle joint for sit-to-stand in a hemiparesis stroke patient: ABA' single-case design

[Purpose] The purpose of this study was to investigate the effect of kinesthetic illusion induced by visual stimulation to the paralyzed side ankle joint on the sit-to-stand of a hemiparesis stroke patient. [Participant and Methods] A 33-year-old male with left hemiparesis due to a right putamen hemorrhage participated. This study used the ABA’ single-case design. Phase A and A’ conducted only conventional physiotherapy. Phase B conducted kinesthetic illusion induced by visual stimulation and conventional physiotherapy. To create a kinesthetic illusion, a video image of the patient’s ankle joint dorsiflexion movement on the non-paralyzed side was inverted and placed on the patient’s paralyzed ankle. The patient observed this display for 5 min. We evaluated weight-bearing symmetry values during sit-to-stand, duration of sit-to-stand, trunk and ankle joint movement on the paralyzed side during sit-to-stand, active ankle dorsiflexion angle on the paralyzed side, and the composite spasticity score. [Results] The weight-bearing symmetry values, movement of the ankle dorsiflexion during sit-to-stand, active ankle dorsiflexion angle, and composite spasticity score were significantly improved in phase B as compared with phase A and the effect was sustained in phase A’. [Conclusion] Kinesthetic illusion induced by visual stimulation for a hemiparesis stroke patient affected the ankle dorsiflexion function, resulting in an improved asymmetry during sit-to-stand as assessed by weight-bearing symmetry values.

Electromyographic Analyses of Trunk Musculature after Stroke: An Integrative Review

Background: Observational and intervention studies examining trunk electromyographic (EMG) activity following stroke are underpowered and fail criteria for systematic reviews of randomized control trials. Objective: To systematically evaluate and summarize evidence about trunk muscle activation after stroke during ADL and with diagnostic and therapeutic interventions.Methods: Search databases were Medline Complete, CINAHL and Health Sources: Nursing Academic Edition. Studies written in English after 1989 included these search terms: stroke, muscle activity, and trunk including abdominal or back muscles. Systematic reviews, single case studies, dissertations, or letters to the editor were excluded. Reviewers used Covidence to screen relevant research and extract information after title, abstract, and full-text screening. Information extracted related to stroke severity, time since onset, specific muscles and EMG analysis technique, and study limitations. Articles were classified as observational, intervention or device-related.Results: The electronic search yielded 188 articles and a hand search found 3. Title and abstract screening yielded 102 articles for full text screening. Ultimately, 45 articles were extracted. Trunk muscle recruitment during function and movement demonstrated significant differences in trunk EMG recruitment timing, magnitude, and symmetry after stroke when compared with healthy participants. Individuals with stroke demonstrated significant differences when comparing paretic to non-paretic side trunk EMG measures. Intervention studies showed some effect on improving trunk muscle activation but they had small sample sizes and methodological issues.Conclusions: Trunk muscle activation after stroke can be monitored with EMG during rehabilitation programs which challenge functional recovery.

Changes in Muscle Activation and Ground Reaction Force of the Lower Limbs According to Foot Placement During Sit-to-Stand Training in Stroke Patients

OBJECTIVE

The aims of the study were to investigate the kinetic effects of sit-to-stand training in various foot positions on the coronal plane in patients with strokes and to suggest appropriate exercises.

DESIGN

Thirty-six poststroke subjects participated in this study. The subjects performed three sit-to-stand trials in the following foot positions: (a) symmetric foot positioning (symmetric), (b) affected foot placed to the side (asymmetric 1), and (c) and less affected foot placed to the side (asymmetric 2). They were asked to perform sit-to-stand training at a spontaneous velocity and remain standing for 5 secs, whereas the vertical ground reaction force was measured using force platforms. The activation of lower limb muscles was evaluated using surface electromyography, and the peak and mean vertical ground reaction force and weight-bearing symmetry ratio were evaluated using force platforms.

RESULTS

Our results showed significant increases in the muscle activation, peak and mean vertical ground reaction force, and weight-bearing symmetry ratio of the lower limbs using the asymmetric 2 strategy (P < 0.05).

CONCLUSIONS

Our results suggest that sit-to-stand training with the less affected foot placed to the side by the width of the subject's foot may be the most beneficial in the rehabilitation of patients with hemiparetic stroke.

Evaluation of Whole-Body Vibration Exercise on Neuromuscular Activation Through Electromyographic Pattern of Vastus Lateralis Muscle and on Range of Motion of Knees in Metabolic Syndrome: A Quasi-Randomized Cross-Over Controlled Trial

Metabolic syndrome (MetS) is related to overweight and obesity, and contributes to clinical limitations. Exercise is used for the management of MetS individuals, who are often not motivated to perform this practice. Whole body vibration exercise (WBVE) produces several biological effects, besides being safe, effective, and feasible for MetS individuals. This pseudo-randomized and cross-over controlled trial study aimed to analyze the effects of WBVE on MetS individuals’ neuromuscular activation using the surface electromyography (sEMG) pattern (root mean square (RMS)) of the vastus lateralis (VL) muscle and on the range of motion (ROM) of the knees. Participants (n = 39) were allocated to two groups: the treatment group (TG), which was exposed to WBVE, and the control group (CG). WBVE interventions were performed twice a week, for a period of 5 weeks. ROM and sEMG were analyzed at baseline, after the first session, and before and after the last session. sEMG (%RMS) significantly increased in the acute effect of the last session of WBVE (108.00 ± 5.07, p < 0.008, right leg; 106.20 ± 3.53, p < 0.02, left leg) compared to the CG. ROM did not significantly change in TG or CG. In conclusion, 5 weeks of WBVE exerted neuromuscular effects capable of increasing VL muscle RMS in individuals with MetS, this effect being potentially useful in the physical rehabilitation of these individuals.

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.

Abdominal muscle activity according to knee joint angle during sit-to-stand

[Purpose] This study assessed the activity of the abdominal muscles according to the angle of the knee joints during sit-to-stand. [Subjects and Methods] Thirty healthy adult males participated in this study. Subjects initiated sit-to-stand at knee joint angles of 60°, 90°, or 120°. An electromyography system was used to measure the maximum voluntary isometric contraction of the rectus abdominis, external oblique, and internal oblique and transverse abdominis muscles. [Results] Percent contraction differed significantly among the three knee joint angles, most notably for the internal oblique and transverse abdominis muscles. [Conclusion] Wider knee joint angles more effectively activate the abdominal muscles, especially those in the deep abdomen, than do narrower angles.