Effect of Anterior Ankle-Foot Orthoses on Weight Shift in Persons With Stroke.

OBJECTIVE: To examine the effects of an anterior ankle-foot orthosis (AAFO) on the speed and accuracy of weight shift in persons with stroke. DESIGN: Cross sectional, repeated measures. SETTING: Neurologic rehabilitation department. PARTICIPANTS: People with stroke (N=24) who were unable to voluntarily dorsiflex the foot against gravity. INTERVENTION: The weight-shift performance was measured with and without the AAFO. MAIN OUTCOME MEASURES: The speed and accuracy of sustained and cyclic bilateral weight shift were measured using the computerized dynamic posturography. The movement velocity, maximum excursion, and directional control of sustained weight shift were calculated using the limits of stability test. The on-axis velocity gap, directional control, and stability of cyclic bilateral weight shift were calculated using the rhythmic weight shift test. RESULTS: For sustained weight shift, the maximum excursion of weight shift to the affected side was greater with the AAFO (P=.002). For cyclic bilateral weight shift, the on-axis velocity gap in the mediolateral (ML) direction was smaller at a fast speed (P=.004). The stability of the ML and anteroposterior weight shift was higher at slow (P=.002 and P<.001, respectively) and fast (P=.001 and P<.001, respectively) speeds when wearing the AAFO. CONCLUSIONS: The findings demonstrated that persons with stroke who wear an AAFO might improve the excursion of the sustained weight shift to the affected side and the speed and stability of cyclic bilateral weight shift in the ML direction.

Effects of an anterior ankle-foot orthosis on walking mobility in stroke patients: get up and go and stair walking.

OBJECTIVE: To examine the effects of an anterior ankle-foot orthosis (AAFO) on walking mobility in stroke patients. DESIGN: Cross-sectional and repeated-measures study design. SETTING: A university's neurologic rehabilitation department. PARTICIPANTS: Ambulant stroke patients (N=21). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Walking mobility was measured by the Timed Up and Go (TUG) test and the Timed Up and Down Stairs (TUDS) test. The paired t test was used to determine the difference between the mobility performances measured with and without the AAFO. RESULTS: There were significant differences between mobility performances with and without an AAFO in the TUG test (P=.038) and the TUDS test (P=.000). CONCLUSIONS: This study supports the effect of an AAFO on walking mobility in stroke patients. The findings demonstrate that stroke patients wearing an AAFO may ambulate with greater speed and safety on level surfaces and stairs.

Effects of the type and direction of support surface perturbation on postural responses.

BACKGROUND: Postural control is organized around a task goal. The two most frequently used types of tasks for postural control research are translational (translation along the anterior-posterior axis) and rotational (rotation in sagittal plane) surface perturbations. These types of perturbations rotate the ankle joint, causing different magnitudes and directions of body sway. The purpose of this study was to investigate the effects of the type (translation vs. rotation) and direction (forward/toe up vs. backward/toe down) of the perturbation on postural responses. METHOD: Nineteen healthy subjects were tested with four perturbations, i.e., forward and backward translation and toe up and toe down rotation. The onset latency and magnitude of muscle activations, angular changes, and COM displacements were measured. In addition, the kinematic data were divided into two phases. The initial phase reflected the balance disturbance induced by the platform movement, and the reversal phase reflected the balance reaction. RESULTS: The results showed that, in the initial phase, rotational perturbation induced earlier ankle movement and faster and larger vertical COM displacement, while translational and forward/toe up perturbations induced larger head and trunk angular change and faster and larger horizontal COM displacement. In the reversal phase, balance reaction was attained by multi-joint movements. Translational and forward/toe up perturbations that induced larger upper body instability evoked faster muscle activation as well as faster and larger hip or knee joint movements. CONCLUSIONS: These findings provide insights into an appropriate support surface perturbation for the evaluation and training of balance.

Effect of age on postural performance and control strategies during changes in visual input and dual-tasking stances.

Background: With age, people begin to experience deterioration in standing balance, especially when sensory input is suddenly removed or added. Here, we sought to explore the effects of age on postural performance and postural control strategies. Methods: The convenience sample consisted of 15 young, 10 middle-aged, and 14 elderly healthy adults. They were instructed to stand with their feet together in four randomly administered conditions involving visual input removal/addition and single-/dual-tasking. Dual-tasking involved continuous subtraction by 3s. Results: Postural sway displacement in the two older groups seemed larger than that in the younger group; however, neither the main effect of group (F2, 36 = 1.152, p = .327) nor the group × time interaction effect (F4, 27 = 0.229, p = .922) was significant. Greater stiffness of the lower leg muscles was observed in the vision-addition condition than in the vision-removal condition in only the elderly group (t13 = -2.755, p = .016). The dual-tasking condition resulted in smaller sway displacement (F1, 36 = 7.690, p = .009) and greater muscle stiffness (F1, 36 = 5.495, p = .025). In the vision-removal condition, the increase in muscle stiffness due to dual-tasking was significantly larger in the middle-aged (t9 = -3.736, p = .005) and elderly groups (t13 = -2.512, p = .026). Conclusions: In healthy older individuals, age-related changes were observed in control strategies used to maintain standing balance upon changes in visual input. The dual-task paradigm induced the use of an ankle-stiffening strategy in middle-aged and elderly adults.

Effect of Marriage on Burnout among Healthcare Workers during the COVID-19 Pandemic.

Since the onset of the COVID-19 pandemic, burnout symptoms have been prevalent among healthcare workers. Living with spouses can be complex and was associated with an increased burnout risk during the COVID-19 pandemic. This study investigated the relationship between living with spouses and burnout among healthcare workers during the COVID-19 pandemic. We distributed questionnaires to participants working in a hospital affiliated with a medical university in Taiwan. The questionnaires were the Copenhagen Burnout Inventory, which comprises personal burnout (PB), work-related burnout (WB), and client burnout subscales; the Nordic Musculoskeletal Questionnaire; and information on basic demographic variables, family factors, living habits, work-related factors, and physical health factors. Multiple linear regression and mediation analysis were used. We obtained 1615 (63.81%) valid questionnaires. After analysis revealed that marriage was an independent risk factor for PB; however, the effect of marriage on WB was nonsignificant after controlling for risk factors. Parenthood, less alcohol use, reported sleep duration less than six hours, less overtime, less shift work, and participation in leisure activities with family and friends were found to be mediators between marriage and a lower WB level. In addition, chronic diseases, frequent neck pain, and shoulder pain were suppression factors. In summary, marriage was associated with an increased risk of PB. Married individuals sustain a high WB level because of changes in family roles, living conditions, and work conditions. Overall, helping healthcare workers to maintain well-being in marriage or family living may be effective in decreasing burnout during the COVID-19 pandemic.

Effects of Different Assistive Seats on Ability of Elderly in Sit-To-Stand and Back-To-Sit Movements.

The ability to perform sit-to-stand (STS) and back-to-sit (BTS) movements is important for the elderly to live independently and maintain a reasonable quality of life. Accordingly, this study investigated the STS and BTS motions of 28 healthy older adults (16 male and 12 female) under three different seat conditions, namely nonassisted, self-designed lifting seat, and UpLift seat. The biomechanical data were acquired using a three-dimensional (3D) motion analysis system and force plates, and were examined by one-way repeated-measures ANOVA to investigate the effects of the different seat conditions on the joint angle, joint moments, and movement duration time (α = 0.05). No significant difference was observed in the STS duration among the three test conditions. However, the BTS duration was significantly increased in the UpLift seat condition. Moreover, the peak flexion angle of the hip during STS motion was also significantly higher in the UpLift condition. For both motions (STS and BTS), the lifting seats significantly decreased the knee and hip joint moments, but significantly increased the ankle joint moment. Moreover, compared to the nonassistive seat, both assistive lifting seats required a greater ankle joint strength to complete the STS and BTS motions.

Effects of different types of sensory signals on reaching performance in persons with chronic schizophrenia.

Previous studies have reported movement abnormalities in persons with schizophrenia. This study aimed to examine the differences between persons with chronic schizophrenia and healthy control participants in reaching movement and the effects of sensory signals on reaching performance in persons with chronic schizophrenia. A counter-balanced repeated-measures design was employed. Twenty persons with schizophrenia and 20 age- and gender-matched control participants were recruited in this study. Reaching performance was measured in three types of sensory signal conditions (visual, auditory, and no signal), i.e., two externally triggered and one self-initiated movement were assessed in reaction time/inter-response interval, movement time, peak velocity, percentage of time in which peak velocity occurred, and movement units. The results revealed significant main effects of group in reaction time/inter-response interval (p = 0.003), movement time (p < 0.001), peak velocity (p < 0.001), and movement units (p < 0.001). The persons with chronic schizophrenia demonstrated slower response to signals and in self-initiated movement, increased movement time, and less forceful and less smooth movement compared to healthy control participants when performing the reaching task. The interaction effect between group and signal in reaction time/inter-response interval was also significant (p < 0.001). The inter-response interval for self-initiated reaching was the shortest in healthy controls. Conversely, the inter-response interval for self-initiated reaching was the longest in persons with schizophrenia. The main effect of the signal on movement time was significant (p < 0.001). The movement time of reaching was longer in response to the auditory signal than in response to visual or self-initiated. The differences in percentages of time in which peak velocity occurred between persons with schizophrenia and healthy controls (p > 0.01) and across the three conditions (p > 0.01) were non-significant. Neither duration of illness nor antipsychotic dosage was significantly associated with reaching performance (all p > 0.01). In conclusion, these findings indicate that reaching movement in persons with chronic schizophrenia is slower, less forceful, and less coordinated compared to healthy control participants. In addition, persons with chronic schizophrenia also had shorter inter-response interval for self-initiated movement and shorter movement time in auditory signal condition, independent of duration of illness and antipsychotic dosage.

Postural Stability of Patients with Schizophrenia during Challenging Sensory Conditions: Implication of Sensory Integration for Postural Control.

Postural dysfunctions are prevalent in patients with schizophrenia and affect their daily life and ability to work. In addition, sensory functions and sensory integration that are crucial for postural control are also compromised. This study intended to examine how patients with schizophrenia coordinate multiple sensory systems to maintain postural stability in dynamic sensory conditions. Twenty-nine patients with schizophrenia and 32 control subjects were recruited. Postural stability of the participants was examined in six sensory conditions of different level of congruency of multiple sensory information, which was based on combinations of correct, removed, or conflicting sensory inputs from visual, somatosensory, and vestibular systems. The excursion of the center of pressure was measured by posturography. Equilibrium scores were derived to indicate the range of anterior-posterior (AP) postural sway, and sensory ratios were calculated to explore ability to use sensory information to maintain balance. The overall AP postural sway was significantly larger for patients with schizophrenia compared to the controls [patients (69.62±8.99); controls (76.53±7.47); t1,59 = -3.28, p<0.001]. The results of mixed-model ANOVAs showed a significant interaction between the group and sensory conditions [F5,295 = 5.55, p<0.001]. Further analysis indicated that AP postural sway was significantly larger for patients compared to the controls in conditions containing unreliable somatosensory information either with visual deprivation or with conflicting visual information. Sensory ratios were not significantly different between groups, although small and non-significant difference in inefficiency to utilize vestibular information was also noted. No significant correlations were found between postural stability and clinical characteristics. To sum up, patients with schizophrenia showed increased postural sway and a higher rate of falls during challenging sensory conditions, which was independent of clinical characteristics. Patients further demonstrated similar pattern and level of utilizing sensory information to maintain balance compared to the controls.

Use of and Self-Perceived Need for Assistive Devices in Individuals with Disabilities in Taiwan.

Assistive devices (ADs) can help individuals with disabilities achieve greater independence, and it can enhance the quality of their lives. This study investigated the use of and self-perceived need for ADs in individuals with disabilities, and determined the influence of gender, age as well as type and degree of disability on the use of and self-perceived need for ADs. This descriptive study utilized a cross-sectional survey design with a convenience sample of participants. A total of 1018 subjects with disabilities who visited an exhibition of assistive technology and two ADs research and development centers completed a questionnaires either by themselves or via a caregiver who completed the questionnaire on behalf of the subject or via interviewers trained specifically for this study. The Mann-Whitney U test and Kruskal-Wallis test were used to determine the influence of participant characteristics on the use of ADs. The results showed that 77.2% and 83.3% of the participants reported that they used and needed AD(s) to engage in activities of daily living. The mean quantity of the use of and self-perceived need for total types of ADs were 3.0 and 5.3, respectively. Participants with different disabilities reported different percentages of the use of various types of ADs. No difference was found between genders and among the age groups in the use of quantity of ADs. Individuals with different types and degrees of disability used different quantities of ADs. Participants with physical, visual and multiple disabilities used significantly more ADs compared to participants with intellectual disability. The total quantity of ADs used increased significantly with increased severity of disability. The mean use of assistive devices was lower compared to the mean need of individuals with disabilities. Further study is required to determine why patients feel the need for but not currently use a specific assistive device.

Effects and after-effects of voluntary intermittent light finger touch on body sway.

Effects of light touch on body sway have usually been investigated with some form of constant contact. Only two studies investigated transient sway dynamics following the addition or withdrawal of light touch. This study adopted a paradigm of intermittent touch and assessed body sway during as well as following short periods of touch of varying durations to investigate whether effects and after-effects of touch differ as a function of touch duration. In a modified heel-to-toe posture, 15 blindfolded participants alternated their index finger position between no-touching and touching on a strain gauge in response to low- and high-pitched auditory cues. Five trials of 46 s duration were segmented into 11 sections: a 6-s no-touching period was followed by five pseudo-randomly ordered touching periods of 0.5-, 1-, 1.5-, 2-, and 5-s duration, each of which was followed by another 6-s no-touching interval. Consistent with previous research, compared to no-touching intervals sway was reduced during touch periods with touch durations greater than 2 s. Progressive reductions in sway were evident after touch onset. After touch withdrawal in the 2-s touch condition, postural sway increased and returned to baseline level nearly immediately. Interestingly, in the 5-s touch condition, reductions in sway persisted even after touch withdrawal in the medio-lateral and antero-posterior plane for around 2.5 s and 5.5 s, respectively. Our intermittent touch paradigm resulted in duration-dependent touch effects and after-effects; the latter is a novel finding and may result from a more persistent postural set involved in proactive sway control.

Gastrocnemius inflexibility on foot progression angle and ankle kinetics during walking.

BACKGROUND: Gastrocnemius inflexibility is a major problem in many orthopedic and neurological patients. Clinically, inflexible gastrocnemius muscles interfere with the performance of functional abilities and associate with many overuse injuries of the lower extremity. The purpose of this study was to investigate the effects of the gastrocnemius inflexibility on the foot progression angle and ankle kinetics during walking. METHODS: There were 50 subjects, 23 patients with the inflexible gastrocnemius and 27 normal subjects, included in this investigation. Participants were asked to walk at two preset cadences of 100 steps/min and 140 steps/min. Data were collected from a motion analysis system and force plates. Kinematic and kinetic variables of gait were computed and analyzed. FINDINGS: Compared with the control group, greater toe-out foot progression angle (P=0.001, effect size=0.314) and knee external rotation (P=0.008, effect size=0.136) were found in the inflexible group during stance phase. Furthermore, significant greater plantarflexion moment (P=0.032, effect size=0.093) and medial ground reaction force (P=0.009, effect size=0.135) during midstance were discovered in the inflexible group. INTERPRETATION: The present results indicate that gastrocnemius inflexibility might bring about the changes in the joint angles, ankle moments and ground reaction forces. The abnormal joint alignment in the lower extremities and greater force upon joint tissue might be significant for the clinical considerations on soft tissue injuries for the patients with inflexible gastrocnemius muscles.

User satisfaction with orthotic devices and service in taiwan.

User satisfaction is afforded considerable importance as an outcome measurement in evidence-based healthcare and the client-centered approach. Several studies have investigated user satisfaction with orthoses. Few studies have investigated user satisfaction with orthoses in Taiwan. Therefore, the purpose of this study was to investigate the user satisfaction with orthotic devices and service using the Taiwanese version of Quebec User Evaluation of Satisfaction with Assistive Technology. We conducted a cross-sectional study of 280 subjects who had used orthoses and received services. The results showed that the mean satisfaction score was 3.74 for the devices and 3.56 for service. Concerning the participants, 69.1% and 59.6% were quite satisfied or very satisfied with their devices and service, respectively. The satisfaction score of orthotic service was lower than that of the devices. Regarding demographic characteristics, participants living in different areas differed only in service score (p = 0.002). The participants living in eastern area and offshore islands were the least satisfied with the orthotic service. For clinical characteristics, there was a significant difference in satisfaction scores among severity of disability (all p = 0.015), types of orthoses (all p = 0.001), and duration of usage (all p = 0.001). The participants with mild disability, wearing the pressure garment and using the orthosis for less than one year, were the most satisfied with their orthotic devices and service. There is a need for improved orthotic devices and services, especially with respect to the comfort of the devices and the provision of subsidy funding.

Postural responses to yaw rotation of support surface.

The purposes of this study were to investigate EMG and kinematic responses to yaw rotation of a support surface. Twenty people participated in four conditions, i.e., two velocities (240°/s, 120°/s) and two amplitudes (30°, 15°). Longer latency and smaller muscle responses were induced for yaw rotation, and distal ankle and knee muscles were activated earlier than trunk and neck muscles. Joint kinematics demonstrated larger angular displacements in axial rotation. Velocity and amplitude did not affect onset latency or magnitude of muscle activation but had significant effects on joint movements and COM displacements. Preliminary information about normative data of healthy subjects was obtained, and questions were generated about optimal velocity and amplitude test protocols that require further investigation.

Effect of forearm axially rotated posture on shoulder load and shoulder abduction / flexion angles in one-armed arrest of forward falls.

BACKGROUND: Falling onto the outstretched hand is the most common cause of upper extremity injury. This study develops an experimental model for evaluating the shoulder load during a simulated forward fall onto one hand with three different forearm axially rotated postures, and examines the shoulder abduction angle and shoulder flexion angle in each case. METHODS: Fifteen healthy young male subjects with an average age of 23.7 years performed a series of one-armed arrests from a height of 5 cm onto a force plate. The kinematics and kinetics of the upper extremity were analyzed for three different forearm postures, namely 45° externally rotated, non-rotated, and 45° internally rotated. FINDINGS: The shoulder joint load and shoulder abduction/flexion angles were significantly dependent on the rotational posture of the forearm. The shoulder medio-lateral shear forces in the externally rotated group were found to be 1.61 and 2.94 times higher than those in the non-rotated and internally rotated groups, respectively. The shoulder flexion angles in the externally rotated, non-rotated and internally rotated groups were 0.6°, 8.0° and 19.2°, respectively, while the corresponding shoulder abduction angles were 6.1°, 34.1° and 46.3°, respectively. INTERPRETATION: In falls onto the outstretched hand, an externally rotated forearm posture should be avoided in order to reduce the medio-lateral shear force acting on the shoulder joint. In falls of this type, a 45° internally rotated forearm posture represents the most effective fall strategy in terms of minimizing the risk of upper extremity injuries.

Effects of foot orthoses on gait patterns of flat feet patients.

BACKGROUND: Although foot orthotics are widely prescribed for the treatment of flatfoot, the biomechanical effects of such devices are not yet fully clear. Accordingly, this study conducted an experimental investigation to evaluate the effects of orthoses on the gait patterns of patients with flatfoot during level walking. METHODS: Eleven adults with flatfoot deformities were recruited. For each participant, kinematic and kinetic data were measured under three test conditions, i.e. walking barefoot, walking with shoes, and walking with shoes and insoles. During each test, the participants' gaits patterns were recorded and analyzed using a motion analysis system, two Kistler force plates and EVaRT software. FINDINGS: The results showed that walking with shoes and insoles and walking with shoes conditions increased the peak ankle dorsiflexion angle and moment, and also reduced the peak ankle plantarflexion angle and moment. Furthermore, walking with shoes and insoles and walking with shoes conditions increased the peak knee varus moment. The effects of the orthoese on knee and hip were minimal and no significant differences were observed between walking with shoes and insoles and walking with shoes. INTERPRETATION: The results suggested that the foot insoles and shoes developed in this study might benefit the ankle joint in patients with flat feet. In view of the minimal changes between walking with shoes and insoles and walking with shoes, further studies may be required to clarify the interaction between the foot and the insole/shoe.

Effect of various forearm axially rotated postures on elbow load and elbow flexion angle in one-armed arrest of a forward fall.

BACKGROUND: Falling onto the outstretched hand is a major cause of upper extremity injury. The overall objectives of this study were to develop an experimental model for elbow load during a simulated fall onto one-armed arrest using three different forearm axially rotated postures as alternative fall arrest strategies. Additionally, the relationship between the elbow flexion angle and different axially rotated postures were also investigated. METHODS: Fifteen healthy young male Taiwanese graduate students with an average age of 23 years were studied. Subjects performed a one-armed arrest of a 5 cm fall onto a force plate. Each subject fell onto the force plate with his forearm 45 degrees axial externally rotated (ER), non-rotated (NR), and 45 degrees axial internally rotated (IR) postures. Kinematics and kinetics of the upper extremity were calculated and analyzed by using laboratory-developed motion analysis procedures. FINDINGS: The valgus-varus shear forces in the ER group were 1.4 times greater than the NR group, and 2.7 times greater than the IR group. The elbow joint remained at almost full extension in the ER (3.9 degrees) group, while elbow flexion angle was observed in the NR (24.6 degrees) and IR (40.3 degrees) groups. INTERPRETATION: A fall onto the outstretched hand with an externally rotated forearm should be avoided in order to reduce excessive valgus-varus shear force on the elbow joint. Knowledge of elbow kinematics and kinetics during a forward fall with various forearm axially rotated posture may be helpful in preventing injuries.