The Effects of Foot Position on the Performance of the Sit-To-Stand Movement With Chronic Stroke Subjects

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 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.

The Effects of Sit-to-Stand Training Combined with Real-Time Visual Feedback on Strength, Balance, Gait Ability, and Quality of Life in Patients with Stroke: A Randomized Controlled Trial

This study aimed to investigate the effects of lower limbs muscles' strength, balance, walking, and quality of life through sit-to-stand training combined with real-time visual feedback (RVF-STS group) in patients with stroke and to compare the effects of classic sit-to-stand training (C-STS group). Thirty patients with stroke were randomly divided into two groups. The RVF-STS group received sit-to-stand training combined with real-time visual feedback using a Wii Balance Board (n = 15), and the C-STS group received classic sit-to-stand training (n = 15). All participants received training for 20 min once a day, 5 days a week for 6 weeks, and both groups underwent general physical therapy for 30 min before training. Before and after the training, the muscle strength of the hip flexor, abductor, and knee extensor were measured, and the Wii Balance Board was used to perform the center of pressure test and Berg Balance Scale to evaluate static and dynamic balance. Additionally, the 10 m walking test and the Timed Up and Go test were performed to evaluate gait function. The Stroke-Specific Quality of Life was used to measure the quality of life. The results showed that the lower extremity muscle strength, balance ability, walking ability, and quality of life of the RVF-STS group significantly improved in comparison of the pre- and post-differences (p < 0.05), and it also showed significant differences between groups (p < 0.05). This study showed that sit-to-stand training combined with real-time visual feedback was effective at improving the muscle strength of the lower extremities, balance, gait, and quality of life in patients with stroke. Therefore, repeating sit-to-stand training combined with real-time visual feedback could be used as an effective treatment method for patients with stroke.

Development of a sit-to-stand assistive device with pressure sensor for elderly and disabled: a feasibility test

Elderly patients face difficulty in performing the sit-to-stand motion; hence, their dependency on assistive devices for activities of daily living is increasing. However, the existing devices do not provide support according to the individual's characteristics. This study aimed to develop a sit-to-stand motion assistive chair that detects the user's weight using a load sensor and assists them to stand up by adjusting the speed themselves as per their weight and preference. Additionally, we investigated the feasibility of the developed device. A device for assisting patients in the sit-to-stand motion in rising up from the chair by electrical motorization was developed. This device senses the load on the seat plate using the load sensor and transmits it to the display through which the users can control the speed themselves using the speed control device. To test its feasibility, the electromyographic muscle activation was analyzed for the erector spinae, quadriceps, tibialis anterior, and gastrocnemius muscles in the sit-to-stand motion using this device in five healthy adults. When compared with the non-use of the device, the use of the developed assistive chair device significantly decreased the muscle activation of the erector spinae, quadriceps, tibialis anterior, and gastrocnemius by 37.27%, 20.44%, 14.50%, and 10.56% on the left and by 17.98%, 24.48%, 32.61%, and 6.05% on the right, respectively. The assistive device with a pressure sensor can effectively assist elderly patients with reduced muscle strength and balance in performing the sit-to-stand motion.

Effectiveness of Heel-Raise-Lower Exercise after Transcutaneous Electrical Nerve Stimulation in Patients with Stroke: A Randomized Controlled Study

OBJECTIVE

This study was conducted to investigate the effect of the heel-raise-lower exercise on spasticity, strength, and gait speed after the application of 30 min of transcutaneous electrical nerve stimulation (TENS) in patients with stroke.

METHODS

The participants were randomly divided into the TENS group and the placebo group, with 20 participants assigned to each group. In the TENS group, heel-raise-lower exercise was performed after applying TENS for six weeks. The placebo group was trained in the same manner for the same amount of time but without electrical stimulation. The spasticity of the ankle plantar flexors was measured using the composite spasticity score. A handheld dynamometer and a 10-m walk test were used to evaluate muscle strength and gait speed, respectively.

RESULTS

Spasticity was significantly more improved in the TENS group (mean change -2.0 ± 1.1) than in the placebo group (mean change -0.4 ± 0.9) (p < 0.05). Similarly, muscle strength was significantly more improved in the TENS group (6.4 ± 3.3 kg) than in the placebo group (4.5 ± 1.6 kg) (p < 0.05). Moreover, participants assigned to the TENS group showed a significant greater improvement in gait speed than those in the placebo group (mean change -5.3 ± 1.4 s vs. -2.7 ± 1.2 s).

CONCLUSIONS

These findings show the benefits of heel-raise-lower exercise after TENS for functional recovery in patients with stroke.

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.

Temporal Features of Muscle Synergies in Sit-to-Stand Motion Reflect the Motor Impairment of Post-Stroke Patients

Sit-to-stand (STS) motion is an important daily activity, and many post-stroke patients have difficulty performing STS motion. Previous studies found that there are four muscle synergies (synchronized muscle activations) in the STS motion of healthy adults. However, for post-stroke patients, it is unclear whether muscle synergies change and which features primarily reflect motor impairment. Here, we use a machine learning method to demonstrate that temporal features in two muscle synergies that contribute to hip rising and balance maintenance motion reflect the motor impairment of post-stroke patients. Analyzing the muscle synergies of age-matched healthy elderly people ( n = 12 ) and post-stroke patients ( n = 33 ), we found that the same four muscle synergies could account for the muscle activity of post-stroke patients. Also, we were able to distinguish post-stroke patients from healthy people on the basis of the temporal features of these muscle synergies. Furthermore, these temporal features were found to correlate with motor impairment of post-stroke patients. We conclude that post-stroke patients can still utilize the same number of muscle synergies as healthy people, but the temporal structure of muscle synergies changes as a result of motor impairment. This could lead to a new rehabilitation strategy for post-stroke patients that focuses on activation timing of muscle synergies.

How toe-out foot positioning influences body-dynamics during a sit-to-stand task

BACKGROUND

Toe-out foot positioning is increasingly analyzed as a compensatory body-mechanical strategy to reduce pain and joint constraints in people with degenerative joint disease during gait. However, its influence during functional tasks, such as sit-to-stand, has not been reported.

RESEARCH QUESTION

How uni- and bilateral toe-out foot positioning influence body-dynamics during a STS task?

METHODS

The study was conducted on 15 healthy participants. Seven feet conditions were tested: neutral (N); right toe-out angle of 10° (U10), 20° (U20), and 30° (U30); bilateral toe-out angle of 10° (B10), 20° (B20), and 30° (B30). Execution time, trunk kinematic, vertical ground reaction force ratio as well as maximal knee and hip joint moments were analyzed and compared.

RESULTS

A significant difference was found across conditions in the STS execution time (p = 0.036) showing a main effect on temporal parameters using both uni- and bilateral toe-out foot positioning. A significant difference between conditions was also obtained for the vertical force ratio (p = 0.018) and the maximal knee flexion moment (p = 0.008). Post-hoc tests demonstrated a significant difference on force ratio and on knee flexion moment only while using a more pronounced unilateral toe-out foot positioning.

SIGNIFICANCE

The influence of toe-out foot positioning on body-dynamics during STS supports the idea of an alteration of body-mechanical strategy, as reported in literature gait studies. The results could have an impact on the management of patients using these strategies in order to reduce the onset of secondary joint diseases such as osteoarthritis.

The Use of Wearable Sensors for the Movement Assessment on Muscle Contraction Sequences in Post-Stroke Patients during Sit-to-Stand

Electromyography (EMG) sensors have been used to study the sequence of muscle contractions during sit-to-stand (STS) in post-stroke patients. However, the majority of the studies used wired sensors with a limited number of placements. Using the latest improved wearable technology with 16 sensors, the current study was a thorough investigation to evaluate the contraction sequences of eight key muscles on the trunk and bilateral limbs during STS in post-stroke patients, as it became feasible. Multiple wearable sensors for the detection of muscle contraction sequences showed that the post-stroke patients performed STS with abnormal firing sequences, not only in the primary mover on the sagittal plane during raising, but also in the tibialis anterior, which may affect anticipatory postural adjustment in the gluteus medius, which may affect balance control. The abnormal tibialis anterior contraction until the early ascending phase and the delayed firing of the gluteus muscles highlight the importance of whole-kinetic-chain monitoring of contraction sequences using wearable sensors. The findings can be helpful for the design of therapeutic exercises.

Transitions sit to stand and stand to sit in persons post-stroke: Path of centre of mass, pelvic and limb loading - A pilot study

BACKGROUND

To explore the movement patterns utilized by persons post stroke from the simultaneous perspective of pelvic and limb loading with the path of centre of mass during the movement transitions sit to stand and stand to sit.

METHODS

A descriptive pilot study where kinetic and kinematic data were collected and compared between the contribution made by the less affected versus more affected lower limb and trunk during sit to stand and stand to sit following stroke. Movement analysis was undertaken using force-plates and a 3D VICON motion capture system.

FINDINGS

Data were successfully collected on nine subjects of whom four presented with left side more affected and eight were male. Two patterns were demonstrated for pelvic loading, four patterns for limb loading and five patterns for deviation of centre of mass. There were no consistent patterns of movement demonstrated dependent upon the more or less affected side. There was no consistent relationship between pelvic and limb loading and deviation of centre of mass throughout the movement phases.

INTERPRETATION

In contrast to assumptions often made with respect to limb loading, we found large variability in movement patterns utilized by person's with a hemiparetic presentation during sit to stand and stand to sit. The findings suggest that movement problems encountered by persons post-stroke are complex and identifies limitations with respect to current measurement techniques.

Effect of foot placements during sit to stand transition on timed up and go test in stroke subjects: A cross sectional study

BACKGROUND & OBJECTIVE

Timed up and go (TUG) test is been used as a screening tool for the assessment of risk of falling in individuals following stroke. Though TUG test is a quick test, it has fair sensitivity compared to other tests. This study was carried out to obtain and compare test scores for different types of foot placements during sit to stand transition in stroke subjects.

METHOD

A Cross-sectional study with purposive sampling included 28 post stroke subjects who were able to walk 6 meter with or without assistance. Timed Up and Go test was carried out with four different types of foot placements and scores were recorded. The data were compared using Kruskal-Wallis One way analysis of variance and Wilcoxon signed ranks test.

RESULT

There were comparable differences between asymmetric 1 test strategy which involved affected extremity to be placed behind the unaffected and other test strategies (Z = -4.457,-3.848,-4.458; p = 0.000).

CONCLUSION

The initial foot placements during sit to stand transition influenced the time taken to complete the test which was significantly higher in asymmetric 1 strategy, Incorporation of the initial foot placement mainly asymmetric 1 strategy into conventional TUG test would help in identifying accurately the subject's functional mobility and postural stability.

Effects of sit-to-stand training combined with transcutaneous electrical stimulation on spasticity, muscle strength and balance ability in patients with stroke: A randomized controlled study

Sit-to-stand is a fundamental movement of human being for performing mobility and independent activity. However, Stroke people symptoms experience difficulty in conducting the sit-to-stand due to paralysis and especially ankle spasticity. Recently, transcutaneouselectrical- stimulation (TENS) is used to reduce pain but also to manage spasticity. The purpose of this study was to determine (1) whether TENS would lead to ankle spasticity reduction and (2) whether sit-to-stand training combined with TENS would improve spasticity, muscle strength and balance ability in stroke patients. Forty-stroke patients were recruited and were randomly divided into two groups: TENS group (n=20) and sham group (n=20). All participants underwent 30-sessions of sit-to-stand training (for 15-min, five-times per week for 6-weeks). Prior to each training session, 30-min of TENS over the peroneal nerve was given in TENS group, whereas sham group received non-electrically stimulated TENS for the same amount of time. Composite-Spasticity-Score was used to assess spasticity level of ankle plantar-flexors. Isometric strength in the extensor of hip, knee and ankle were measured by handheld dynamometer. Postural-sway distance was measured using a force platform. The spasticity score in the TENS group (2.6±0.8) improved significantly greater than the sham group (0.7±0.8, p<0.05). The muscle strength of hip extensor in the TENS group (2.7±1.1kg) was significantly higher than the sham group (1.0±0.8kg, p<0.05). Significant improvement in postural-sway was observed in the TENS group compared to the sham group (p<0.05). Thus, sit-to-stand training combined with TENS may be used to improve the spasticity, balance function and muscle strength in stroke patients.

The effects of visual control whole body vibration exercise on balance and gait function of stroke patients

[Purpose] This study aims to verify the effects of visual control whole body vibration exercise on balance and gait function of stroke patients. [Subjects and Methods] A total of 22 stroke patients were randomly assigned to two groups; 11 to the experimental group and 11 to the control group. Both groups received 30 minutes of Neuro-developmental treatment 5 times per week for 4 weeks. The experimental group additionally performed 10 minutes of visual control whole body vibration exercise 5 times per week during the 4 weeks. Balance was measured using the Functional Reach Test. Gait was measured using the Timed Up and Go Test. [Results] An in-group comparison in the experimental group showed significant differences in the Functional Reach Test and Timed Up and Go Test. In comparing the groups, the Functional Reach Test and Timed Up and Go Test of the experimental group were more significantly different compared to the control group. [Conclusion] These results suggest that visual control whole body vibration exercise has a positive effect on the balance and gait function of stroke patients.

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.

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

[Purpose] The purpose of this study was to determine the activation timing patterns of abdominal and leg muscles during the sit-to-stand movement in individuals with chronic hemiparetic stroke. [Subjects] Twenty adults with chronic hemiparetic stroke participated in this study. [Methods] Subjects performed five sit-to-stand movements at a self-selected velocity without using their hands. Surface electromyography was used to measure the reaction time of the bilateral transverse abdominis/internal oblique, rectus femoris, and tibialis anterior muscles during the sit-to-stand movement. [Results] There were significant differences in the reaction time between the affected and unaffected sides of the abdominal and leg muscles. Muscles on the unaffected side had faster reaction time than those on the affected side. Activation of the transverse abdominis/internal oblique muscles was delayed relative to activation of the tibialis anterior muscle during the sit-to-stand movement. [Conclusion] Our findings provide information that may aid clinicians in the examination and management of paretic muscles for transfers in individuals with chronic hemiparetic stroke.

Sit-to-stand biomechanics of individuals with multiple sclerosis

BACKGROUND

It is unclear how people with multiple sclerosis, who often have compromised strength and balance, compare to healthy controls during sit-to-stand movements. The purpose of this study was to compare sit-to-stand biomechanics among three groups: people with multiple sclerosis who exhibit leg weakness, people with multiple sclerosis who have comparable strength to controls, and healthy controls.

METHODS

Twenty-one individuals with multiple sclerosis (n=10 exhibiting leg weakness: n=11 exhibiting comparable strength to controls), and 12 controls performed five sit-to-stand trials while kinematic data and ground reaction forces were captured. ANOVAs followed by Tukey's post-hoc tests (α=0.05) were used to determine group and limb differences for leg strength, movement time, and sagittal-plane joint kinematics and kinetics.

FINDINGS

Persons with multiple sclerosis exhibiting leg weakness displayed decreased leg strength, greater trunk flexion, faster trunk flexion velocity and decreased knee extensor power compared to the other two groups (p<0.05; d≥0.87), and slower rise times compared to controls(p<0.03; d≥1.17). No differences were found between controls and the multiple sclerosis-comparable strength group. Across all 3 groups, leg strength was moderately correlated with trunk kinematics and knee extensor velocities, moments and powers of the sit-to-stand (p≤0.05).

INTERPRETATION

Participants with multiple sclerosis exhibiting leg weakness took longer to stand and appeared to use a trunk-flexion movement strategy when performing the sit-to-stand. The majority of group differences appear to be a result of leg extension weakness. Treatment that includes leg strengthening may be necessary to improve sit-to-stand performance for people with multiple sclerosis.

Effects of foot position of the nonparetic side during sit-to-stand training on postural balance in patients with stroke

[Purpose] We aimed to investigate postural balance after sit-to-stand (STS) training with different nonparetic foot positions in stroke patients. [Subjects] Thirty-six subjects who experienced a stroke (21 males, 15 females) participated and were divided into the symmetric foot position (SYMM), asymmetric foot position (ASYM), and step foot (STEP) groups. [Methods] Each group performed repetitive sit-to-stand training 5 times a week for 6 weeks. The timed up-and-go test (TUG), functional reach test (FRT), and F-mat system correcting the anterior/posterior (A-P) and medial/lateral (M-L) distance of the center of pressure (COP) were used to measure the static and dynamic postural balance pre- and postintervention. ANCOVA was used to analyze differences among groups, and preintervention variables were used as covariates. [Results] The TUG, FRT, and A-P and M-L distance of the COP in the ASYM and STEP groups were significantly decreased after intervention compared with the SYMM group. All parameters in the STEP group were lower than those in the ASYM group, without a significant difference. [Conclusion] The asymmetric foot position during STS is a good intervention to improve the static and dynamic postural balance in stroke patients. Especially, using a step to change the foot position is effective in improving STS performance.

Repetitive sit-to-stand training with the step-foot position on the non-paretic side, and its effects on the balance and foot pressure of chronic stroke subjects

[Purpose] This study aimed to improve the asymmetrical weight-bearing ratio by applying repetitive sit-to-stand training methods that feature a step-foot position to the paretic-side foot of hemiplegic patients; it sought also to provide the information needed to apply weight-bearing and balance training to hemiplegic patients. [Subjects and Methods] The subjects were divided into two groups: a spontaneous group and a step group. They all performed repetitive sit-to-stand training five times per week for a total of six weeks. The Biodex Balance System, TUG, and 5XSST were used to measure the static and dynamic standing balance of each patient. A foot mat system was used to measure foot pressure. [Results] In the balance measurements, differences in the Overall index, Ant-post index, Med-lat index, Fall risk index, TUG, and 5XSST after training was significantly different between the two study groups. In evaluating foot pressure measurements, we found that the COP (Ant-post), Peak pressure: hind foot, and Contact area: hind foot measurements significantly differed between the groups after the training. [Conclusion] Repetitive sit-to-stand training that involves positioning the non-paretic leg upward can be considered a significant form of training that improves the symmetric posture adjustment and balance of hemiplegic patients following a stroke.

Effect of arm position and foot placement on the five times sit-to-stand test completion times of female adults older than 50 years of age

The five times-sit-to stand test (FTSTS) is a clinical test which is commonly used to assessed the functional muscle strength of the lower limbs of older adults. The aim of this study was to examine the effect of different arm positions and foot placements on the FTSTS completion times of older female adults. [Subjects and Methods] Twenty-nine healthy female subjects, aged 63.1±5.3 years participated in this cross-sectional study. The times required to complete the FTSTS with 3 different arm positions (hands on thighs, arms crossed over chest, and an augmented arm position with the arms extended forward) and 2 foot placements (neutral and posterior) were recorded. The interaction effect and main effect of arm positions and foot placements were examined using a 3 (arm position) × 2 (foot placement) two-way repeated measures analysis of variance (ANOVA). [Results] There was no interaction effect among the 3 arm positions in the 2 foot placements. A significant main effect was identified for foot placement, but not arm position. Posterior foot placement led to a shorter FTSTS time compared to that of normal foot placement. [Conclusion] With the same arm position, FTSTS completion times with posterior foot placement tended to be shorter. Therefore, the standard foot placement should be used for FTSTS administration.

Unstable Surface Improves Quadriceps:Hamstring Co-contraction for Anterior Cruciate Ligament Injury Prevention Strategies

Background:

Increasing quadriceps:hamstring muscular co-contraction at the knee may reduce the risk of anterior cruciate ligament (ACL) injury. The purpose of this investigation was to examine muscle activation in the quadriceps and hamstrings and peak kinematics of the knee, hip, and trunk when performing a single-leg drop (SLD) on to a Bosu ball (unstable surface) compared with on to the floor (stable surface).

Hypotheses:

(1) The SLD on an unstable surface would lower the quadriceps to hamstrings electromyographic (EMG) activation ratio (Q:H EMG activation ratio) compared with being performed on the floor. (2) Lower Q:H EMG activation ratio would be caused by a relative increase in hamstring activation, with no significant change in quadriceps activation.

Study Design:

Controlled laboratory study.

Methods:

Thirty-nine Division I National Collegiate Athletic Association (NCAA) female athletes performed 3 SLDs per leg onto a Bosu ball and onto the floor. Muscle activity of the vastus lateralis and lateral hamstrings were used to estimate peak quadriceps and hamstring activation, along with the Q:H EMG activation ratio. Kinematic measures at the knee, hip, and trunk were also estimated. Differences between landings were assessed using a 2-level analysis of variance (limb and surface).

Results:

The maximum Q:H EMG activation ratio was significantly reduced when athletes performed an SLD onto the Bosu ball (20%, P < 0.001) compared with the floor. Peak hamstring activity was higher when athletes landed on a Bosu ball (18% higher, P = 0.029) compared with when they landed on the floor.

Conclusion:

Compared with landing on the floor (a stable surface), landing on a Bosu ball (unstable surface) changed the athlete’s co-contraction at the knee and increased hamstring activity. However, landing on a Bosu ball also decreased the athlete’s knee flexion, which was an undesired effect.

Clinical Relevance:

These findings highlight the potential utility of unstable surfaces as a training tool to reduce the risk of ACL injury in female athletes.

The effect of foot position on erector spinae and gluteus maximus muscle activation during sit-to-stand performed by chronic stroke patients

[Purpose] The aim of this study was to use surface electromyography (EMG) to investigate the effects of different foot positioning on bilateral erector spinae (ES) and gluteus maximus (GM) activation during sit-to-stand performed by individuals with stroke. [Subjects] Fifteen randomly selected participants with stroke were enrolled in this study. [Methods] All the participants were asked to perform sit-to-stand (STS) using three different strategies: (1) symmetric foot position, (2) unaffected foot placed behind the affected foot position (asymmetric-1), (3) affected foot placed behind the unaffected foot position (asymmetric-2). An EMG system was used to measure ES and GM muscle activities. The strategies were performed in a random order, and the mean values of five measurements were used in the analysis. One-way repeated measure ANOVA was used to determine the statistical significance of differences between the conditions. [Results] The affected ES muscle activity was significantly greater in asymmetric-2 (180.7±73.4) than in symmetrical foot placement (149.8±54.2). In addition, the affected ES, unaffected ES, and affected GM muscle activity were significantly greater in asymmetric-2 (180.7±73.4, 173.5±83.1, 98.3±90.3 respectively) than in asymmetric-1 foot placement (147.3±53.8, 151.2±76.5, 84.9±73.8 respectively). [Conclusion] Our results suggest that it may be more desirable for persons with stroke to place the affected foot behind the unaffected foot when performing STS to increase affected ES and GM muscle activation.

Subjective measures in sit-to-stand task in post-stroke hemiparesis: comment on Brière, Nadeau, Lauzière, and Gravel (2013)

In a recent study, Brière, Nadeau, Lauzière, and Gravel (2013 ) examined the perceptions of individuals post-stroke on their weight-bearing distribution and knee effort distribution in sit-to-stand tasks. The present comment emphasized the importance of the feeling of post-stroke hemiparesis in sit-to-stand task and identified areas of improvements of the target study.

Effects of dynamic stepping training on nonlocomotor tasks in individuals poststroke

BACKGROUND

During the physical rehabilitation of individuals poststroke, therapists are challenged to provide sufficient amounts of task-specific practice in order to maximize outcomes of multiple functional skills within limited visits. Basic and applied studies have suggested that training of one motor task may affect performance of biomechanically separate tasks that utilize overlapping neural circuits. However, few studies have explicitly investigated the impact of training one functional task on separate, nonpracticed tasks.

OBJECTIVE

The purpose of this preliminary study was to investigate the potential gains in specific nonlocomotor assessments in individuals poststroke following only stepping training of variable, challenging tasks at high aerobic intensities.

METHODS

Individuals with locomotor deficits following subacute and chronic stroke (n=22) completed a locomotor training paradigm using a repeated-measures design. Practice of multiple stepping tasks was provided in variable environments or contexts at high aerobic intensities for ≥40 sessions over 10 weeks. The primary outcome was timed Five-Times Sit-to-Stand Test (5XSTS) performance, with secondary measures of sit-to-stand kinematics and kinetics, clinical assessment of balance, and isometric lower limb strength.

RESULTS

Participants improved their timed 5XSTS performance following stepping training, with changes in selected biomechanical measures. Statistical and clinically meaningful improvements in balance were observed, with more modest changes in paretic leg strength.

CONCLUSIONS

The present data suggest that significant gains in selected nonlocomotor tasks can be achieved with high-intensity, variable stepping training. Improvements in nonpracticed tasks may minimize the need to practice multiple tasks within and across treatment sessions.

Foot placement and arm position affect the five times sit-to-stand test time of individuals with chronic stroke

Objectives. To investigate the effect of two foot placements (normal or posterior placement) and three arm positions (hands on the thighs, arms crossed over chest, and augmented arm position with elbow extended) on the five times sit-to-stand (FTSTS) test times of individuals with chronic stroke. Design. Cross-sectional study. Setting. University-based rehabilitation clinic. Participants. A convenience sample of community-dwelling individuals with chronic stroke (N = 45). Methods. The times in completing the FTSTS with two foot placements and the three arm positions were recorded by stopwatch. Results. Posterior foot placement led to significantly shorter FTSTS times when compared with normal foot placement in all the 3 arm positions (P ≤ 0.001). In addition, hands on thigh position led to significantly longer FTSTS times than the augmented arm position (P = 0.014). Conclusion. Our results showed that foot placement and arm position could influence the FTSTS times of individuals with chronic stroke. Standardizing the foot placement and arm position in the test procedure is essential, if FTSTS test is intended to be used repeatedly on the same subject.

Interventions for improving sit-to-stand ability following stroke

BACKGROUND

Standing up from a seated position is one of the most frequently performed functional tasks, is an essential pre-requisite to walking and is important for independent living and preventing falls. Following stroke, patients can experience a number of problems relating to the ability to sit-to-stand independently.

OBJECTIVES

To review the evidence of effectiveness of interventions aimed at improving sit-to-stand ability after stroke. The primary objectives were to determine (1) the effect of interventions that alter the starting posture (including chair height, foot position, hand rests) on ability to sit-to-stand independently; and (2) the effect of rehabilitation interventions (such as repetitive practice and exercise programmes) on ability to sit-to-stand independently. The secondary objectives were to determine the effects of interventions aimed at improving ability to sit-to-stand on: (1) time taken to sit-to-stand; (2) symmetry of weight distribution during sit-to-stand; (3) peak vertical ground reaction forces during sit-to-stand; (4) lateral movement of centre of pressure during sit-to-stand; and (5) incidence of falls.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (June 2013), CENTRAL (2013, Issue 5), MEDLINE (1950 to June 2013), EMBASE (1980 to June 2013), CINAHL (1982 to June 2013), AMED (1985 to June 2013) and six additional databases. We also searched reference lists and trials registers and contacted experts.

SELECTION CRITERIA

Randomised trials in adults after stroke where: the intervention aimed to affect the ability to sit-to-stand by altering the posture of the patient, or the design of the chair; stated that the aim of the intervention was to improve the ability to sit-to-stand; or the intervention involved exercises that included repeated practice of the movement of sit-to-stand (task-specific practice of rising to stand).The primary outcome of interest was the ability to sit-to-stand independently. Secondary outcomes included time taken to sit-to-stand, measures of lateral symmetry during sit-to-stand, incidence of falls and general functional ability scores.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened abstracts, extracted data and appraised trials. We undertook an assessment of methodological quality for random sequence generation, allocation concealment, blinding of outcome assessors and method of dealing with missing data.

MAIN RESULTS

Thirteen studies (603 participants) met the inclusion criteria for this review, and data from 11 of these studies were included within meta-analyses. Twelve of the 13 included studies investigated rehabilitation interventions; one (nine participants) investigated the effect of altered starting posture for sit-to-stand. We judged only four studies to be at low risk of bias for all methodological parameters assessed. The majority of randomised controlled trials included participants who were already able to sit-to-stand or walk independently.Only one study (48 participants), which we judged to be at high risk of bias, reported our primary outcome of interest, ability to sit-to-stand independently, and found that training increased the odds of achieving independent sit-to-stand compared with control (odds ratio (OR) 4.86, 95% confidence interval (CI) 1.43 to 16.50, very low quality evidence).Interventions or training for sit-to-stand improved the time taken to sit-to-stand and the lateral symmetry (weight distribution between the legs) during sit-to-stand (standardised mean difference (SMD) -0.34; 95% CI -0.62 to -0.06, seven studies, 335 participants; and SMD 0.85; 95% CI 0.38 to 1.33, five studies, 105 participants respectively, both moderate quality evidence). These improvements are maintained at long-term follow-up.Few trials assessing the effect of sit-to-stand training on peak vertical ground reaction force (one study, 54 participants) and functional ability (two studies, 196 participants) were identified, providing very low and low quality evidence respectively.The effect of sit-to-stand training on number of falls was imprecise, demonstrating no benefit or harm (OR 0.75, 95% CI 0.46 to 1.22, five studies, 319 participants, low quality evidence). We judged the majority of studies that assessed falls to be at high risk of bias.

AUTHORS' CONCLUSIONS

This review has found insufficient evidence relating to our primary outcome of ability to sit-to-stand independently to reach any generalisable conclusions. This review has found moderate quality evidence that interventions to improve sit-to-stand may have a beneficial effect on time taken to sit-to-stand and lateral symmetry during sit-to-stand, in the population of people with stroke who were already able to sit-to-stand independently. There was insufficient evidence to reach conclusions relating to the effect of interventions to improve sit-to-stand on peak vertical ground reaction force, functional ability and falls. This review adds to a growing body of evidence that repetitive task-specific training is beneficial for outcomes in people receiving rehabilitation following stroke.

Sit-to-Stand in People with Stroke: Effect of Lower Limb Constraint-Induced Movement Strategies

Background. Weight-bearing asymmetry and impaired balance may contribute to the increased fall risk in people with stroke when rising to stand from sitting. Objective. This study investigated the effect of constraint-induced movement (CIM) strategies on weight-bearing symmetry and balance during sit-to-stand in people with stroke. Methods. A nonrandom convenience sample of fifteen people with stroke performed the sit-to-stand task using three CIM strategies including a solid or compliant (foam) block strategy, with the unaffected limb placed on the block, and an asymmetrical foot position strategy, with the unaffected limb placed ahead of the affected limb. Duration of the task, affected limb weight-bearing, and centre of pressure and centre of mass displacement were measured in the frontal and sagittal plane. Results. Affected limb weight-bearing was increased and frontal plane centre of pressure and centre of mass moved toward the affected limb compared to baseline with all CIM strategies. Centre of mass displacement in the sagittal plane was greater with the compliant block and asymmetrical foot strategies. Conclusions. The CIM strategies demonstrated greater loading of the affected limb and movement of the centre of pressure and centre of mass toward the affected limb. The compliant block and asymmetrical foot conditions may challenge sagittal plane balance during sit-to-stand in people with stroke.

Lower limb muscle activation during the sit-to-stand task in subjects who have had a stroke

OBJECTIVE

The aim of this study was to compare electromyographic activities between and within the paretic and nonparetic lower limb muscles during the sit-to-stand (STS) task in subjects with hemiparesis as a result of stroke.

DESIGN

This is a cross-sectional study.

RESULTS

All monitored muscles of both lower limbs remained active during most of the sit-to-stand task; the muscles were activated before the seat-off and reached the maximum peak of electromyographic activity after the seat-off (P < 0.01). As compared with the paretic limb, the nonparetic limb exhibited earlier activation of the hamstrings (P < 0.01); longer activation period (P < 0.01); and higher electromyographic activity of the tibialis anterior, the soleus, and the quadriceps (P ≤ 0.02). The activity onset time was similar in all muscles of the nonparetic lower limb (P ≥ 0.053), whereas the tibialis anterior of the paretic lower limb was activated before the hamstring and the soleus (P ≤ 0.015). These results illustrate that muscle activation of both limbs during the sit-to-stand task was impaired but in a higher level in the paretic side.

CONCLUSIONS

Neuromuscular coordination abnormalities were observed in both lower limbs. The paretic limb was unable to recruit the muscles at the proper time and to achieve the amplitude for executing the sit-to-stand task, whereas significant compensations occurred on the nonparetic side.

Is it correct to always consider weight-bearing asymmetrically distributed in individuals with hemiparesis?

Injuries may cause unilateral deterioration of brain areas related to postural control resulting in lateralized motor disability with abnormal asymmetry in weight-bearing distribution. Although overloading toward the nonaffected limb has been described as the preferred posture among individuals with hemiparesis, characterization of the weight-bearing asymmetry is poorly and indirectly described. Therefore, this study aimed to describe weight-bearing distribution during upright stance, establishing criteria to consider asymmetry in hemiparesis when analyzed within the limits defined by controls matched by age and gender. Forty subjects with (n = 20) or without hemiparesis (n = 20) were included in procedures to record weight-bearing values between hemibodies, and these values were used to calculate a symmetry ratio. Control presented 95% confidence interval (CI) of the mean for symmetry ratio ranging from 0.888 to 1.072, defining limits to symmetry. Four subjects with hemiparesis (20%) had symmetry ratios inside limits defined by controls (i.e., weight-bearing symmetrically distributed), and 11 (55%) subjects without hemiparesis showed symmetry ratios outside the limits, suggesting asymmetrical weight-bearing distribution. It was concluded that asymmetry, when present in a control group, was more frequently overloading nonpredominantly used hemibody (nondominant side), differing from a hemiparesis group commonly forced to assume the nonaffected side as the predominantly used hemibody and where the overload was observed.