Effect of a rigid ankle foot orthosis and an ankle foot orthosis with an oil damper plantar flexion resistance on pelvic and thoracic movements of patients with stroke during gait.

BACKGROUND: Impairments of trunk movements in gait of stroke are often reported. Ankle foot orthosis (AFO) is commonly used to improve gait of stroke; however, the effect of different types of AFOs on the pelvic and thoracic movements during gait in stroke has not been clarified. METHODS: Thirty-four patients with stroke were randomly allocated to undergo 2 weeks of gait training by physiotherapists while wearing a rigid AFO (RAFO) with a fixed ankle or an AFO with an oil damper (AFO-OD) that provides plantarflexion resistance and free dorsiflexion. A motion capture system was used for measurements of shod gait without AFO at baseline and with and without AFO after gait training. Two-way repeated ANOVA, Wilcoxon signed-rank test, and Mann-Whitney U test were performed for the data after the gait training to know the effect of different kinds of AFOs. RESULTS: Twenty-nine patients completed the study (AFO-OD group: 14, RAFO group: 15). Interactions were found in pelvic rotation angle, change of shank-to-vertical angle (SVA) in the stance, and paretic to non-paretic step length, which increased in AFO-OD group with AFOs (p < 0.05), while the SVA decreased in RAFO group with AFOs (p < 0.05). The main effects were found in pelvic rotation at the contralateral foot off, and thoracic tilt at foot off when an AFO was worn. The change of SVA in stance was positively correlated with the pelvic rotation in the AFO-OD group (r = 0.558). At initial contact, pelvic rotation was positively correlated with thoracic rotation in both groups. CONCLUSIONS: The findings in 29 patients with stroke showed that pelvic and thoracic movements especially the rotation were affected by the type of AFOs. Pelvic rotation and lower limb kinematics exhibited significant improvements with AFO-OD, reflecting more desirable gait performance. On the other hand, the increase in thoracic in-phase rotation might expose the effect of insufficient trunk control and dissociation movement. Trial registration UMIN000038694, Registered 21 November 2019, https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_his_list.cgi?recptno=R000044048 .

Ankle-foot orthosis with an oil damper versus nonarticulated ankle-foot orthosis in the gait of patients with subacute stroke: a randomized controlled trial.

BACKGROUND: Gait improvement in patients with stroke has been examined in terms of use or non-use of an ankle-foot orthosis (AFO), but the effects of different kinds of AFOs remain unclear. In this study, the effect on gait of using an AFO with an oil damper (AFO-OD), which has plantarflexion stiffness without dorsiflexion resistance, was compared with a nonarticulated AFO, which has both dorsiflexion and plantarflexion stiffness, in a randomized controlled trial. METHODS: Forty-one patients (31 men, 10 women; mean age 58.4 ± 11.3 years) in the subacute phase of stroke were randomly allocated to two groups to undergo gait training for 1 h daily over 2 weeks by physiotherapists while wearing an AFO-OD or a nonarticulated AFO. A motion capture system was utilized to measure shod gait without orthosis at baseline and after training with the allocated AFO. Data analysis focused on the joint kinematics and kinetics, spatial and temporal parameters, ground reaction force, and shank-to-vertical angle. Unpaired t-test or Mann-Whitney U test was performed to clarify the difference in gait with an AFO between the two AFO groups after training, with a significance level of p = 0.05. RESULTS: Thirty-six patients completed the study (17 in the AFO-OD group and 19 in the nonarticulated AFO group). The ankle joint was more dorsiflexed in single stance (p = 0.008, effect size r = 0.46) and peak ankle power absorption was larger in stance (p = 0.007, r = 0.55) in the AFO-OD group compared with the nonarticulated AFO group. Peak power absorption varied among patients in the AFO-OD group. Increased dorsiflexion angles were also found at initial contact (p = 0.008, r = 1.51), pre-swing (p = 0.045, r = 0.91), and the swing phase (p = 0.045, r = 0.91) in the AFO-OD group. There was no difference in peak plantarflexion moment, ankle power generation, spatial or temporal parameters, ground reaction force, or shank-to-vertical angle between the two groups. CONCLUSIONS: The results of this study showed that an AFO with plantarflexion stiffness but without dorsiflexion resistance produced greater improvement in ankle joint kinematics and kinetics compared with the nonarticulated AFO, but the results of peak power absorption varied greatly among patients. Trial registration UMIN000028126, Registered 1 August 2017, https://upload.umin.ac.jp/cgi-bin/icdr/ctr_menu_form_reg.cgi?recptno=R000032197.

Effect of different seat heights on lumbar spine flexion during stand-to-sit motion.

[Purpose] This study aimed to investigate the movement of the thorax, lumbar spine, and pelvis when healthy participants sit on a chair, and to identify the kinematic characteristics due to changes in the height of the seat. [Participants and Methods] Twenty healthy participants (14 males, 6 females; mean age, 29 ± 5 years) were recruited for this study. They performed stand-to-sit motion using one seat with a height of 100% that of the lower leg length (standard) and another with a height of 60% that of the lower leg length (lower). A three-dimensional motion analysis system and four force plates were used to analyze each joint angle. [Results] The mean lumbar spine flexion angle was significantly increased in the lower versus the standard seat. As a kinematic characteristic, the pelvis tilted posteriorly while the thorax tilted anteriorly, which increased the lumbar spine flexion angle. The pelvis was tilted posteriorly when the hip joint flexed about 60° regardless of the seat height. [Conclusion] The lumbar spine flexion angle increased in the lower seat stand-to-sit motion, which suggested an increase in the load on the lumbar spine. The lumbar spine flexion angle was influenced by the characteristic movements of the thorax and pelvis.

Where do healthy older adults take more time during the Timed Up and Go test?

[Purpose] We need to regularly evaluate motor function to sustain the health of community-dwelling older adults. Our study aimed to identify the kinematic characteristics of healthy older adults in the Timed Up and Go test because the criteria for assessing the motor function of healthy older adults are unclear in the widely used clinical simple methods. [Participants and Methods] In total, 22 healthy younger and 28 healthy older adults participated in this study. Using a 3D motion analysis system, we measured the time ratios, trajectories, trajectory length per unit time, and body inclination angles during the Timed Up and Go test. We compared the kinematic characteristics of the older and younger adults. [Results] The older adults required a longer time ratio to complete the turn and sit subtasks. The trajectory of the older adults' turn subtask was longer than that of the younger adults. Older adults' body inclination angles during the turn subtask were smaller than that of the younger adults. [Conclusion] Healthy older adults had a different kinematic index from younger adults during the Timed Up and Go turn subtask. Therefore, we suggest the kinematic index of posture and turning radius be used to measure Timed Up and Go as a clinically useful index for understanding the motor characteristics of older adults.

The relationship between movement of the shank while running and foot alignment factors that lead to the onset of Achilles peritendinitis.

[Purpose] To clarify the relationship between movement of the shank relative to the global reference frame (shank angle) while running, and foot alignment factors that lead to the onset of Achilles peritendinitis. [Participants and Methods] This study included 54 healthy male participants. Running at a constant speed was measured by three-dimensional motion analysis. The shank angle at the time of the first peak of vertical ground reaction force and maximum ankle dorsiflexion were analyzed. The magnitude of ankle plantarflexion, inversion, and adduction angle in the propulsive phase as well as static foot alignment (navicular index, and range of ankle dorsiflexion angle) were measured. The relationships between shank angle features and these parameters were investigated. [Results] Outward inclination of the shank occurred at the time of the first peak of vertical ground reaction force and maximum ankle dorsiflexion, with this increase in movement correlating with parameters that increased the risk of Achilles peritendinitis. [Conclusion] These findings suggest that evaluation of the shank angle on the frontal plane while running may be used to estimate the onset of Achilles peritendinitis in clinical practice.

Changes in kinematic chain dynamics between calcaneal pronation/supination and shank rotation during load bearing associated with ankle position during plantar and dorsiflexion.

[Purpose] This study aimed to elucidate the dynamics of the kinematic chain of shank rotation accompanying calcaneal pronation/supination during weight-bearing changes associated with ankle positions during plantar/dorsiflexion and whether this biomechanical phenomenon is affected by age. [Participants and Methods] The study included 54 participants (108 legs, 25 young and 29 old participants). A 3-dimensional motion analysis system measured the calcaneal pronation/supination and the shank rotation angles during pronation/supination of the foot when upright. The kinematic chain ratio was defined as the linear regression coefficient (shank rotation angle/calcaneal pronation/supination angle). The kinematic chain ratio was measured during plantar flexion, in an intermediate position, and dorsiflexion. [Results] Significant differences in the kinematic chain ratio were related to ankle position but not age. The mean kinematic chain ratio in all participants was 0.9 ± 0.3 for plantar flexion, 1.0 ± 0.2 for an intermediate position, and 1.3 ± 0.4 for dorsiflexion, showing significant differences between the 3 ankle positions. [Conclusion] During dorsiflexion, the long axis of the shank and that of the subtalar joint are nearly parallel; thus, shank rotation increases (larger kinematic chain ratio). During plantar flexion, a larger angle is created; thus, shank rotation decreases (smaller kinematic chain ratio). When analyzing the kinematic chain between calcaneal pronation/supination and shank rotation, it is essential to consider the ankle position during plantar/dorsiflexion.

Factors that determine kinematic coupling behavior of calcaneal pronation/supination and shank rotation during weight bearing: ananalysis based on foot bone alignment using radiographic images.

[Purpose] This study aimed to identify factors that determine the kinematic coupling behavior of calcaneal pronation/supination and shank rotation in a standing position. [Participants and Methods] Study participants included 15 healthy adults (30 legs). Kinematic coupling behavior was quantified as the linear regression coefficient (kinetic chain ratio [KCR]) of the angle of shank rotation against the angle of calcaneal pronation-to-supination measured using a 3-dimensional motion analysis system during pronation and supination of both feet while standing. The relationship between the KCR and the foot bone alignment was also analyzed using 35 parameters that were evaluated based on plain radiography. [Results] Greater the height of the medial longitudinal arch, and greater the backward tilt of the long axis of the talus and the backward tilt of the talar articular surface of the calcaneus, larger the KCR. This alignment differed between the genders. [Conclusion] This study suggested that the KCR increases as the subtalar joint axis approaches the long axis of the shank secondary to the lifting of the medial longitudinal arch of the foot and decreases as the subtalar joint axis approaches the long axis of the foot secondary to the lowering of the medial longitudinal arch of the foot.

CyanoBase and RhizoBase: databases of manually curated annotations for cyanobacterial and rhizobial genomes.

To understand newly sequenced genomes of closely related species, comprehensively curated reference genome databases are becoming increasingly important. We have extended CyanoBase (http://genome.microbedb.jp/cyanobase), a genome database for cyanobacteria, and newly developed RhizoBase (http://genome.microbedb.jp/rhizobase), a genome database for rhizobia, nitrogen-fixing bacteria associated with leguminous plants. Both databases focus on the representation and reusability of reference genome annotations, which are continuously updated by manual curation. Domain experts have extracted names, products and functions of each gene reported in the literature. To ensure effectiveness of this procedure, we developed the TogoAnnotation system offering a web-based user interface and a uniform storage of annotations for the curators of the CyanoBase and RhizoBase databases. The number of references investigated for CyanoBase increased from 2260 in our previous report to 5285, and for RhizoBase, we perused 1216 references. The results of these intensive annotations are displayed on the GeneView pages of each database. Advanced users can also retrieve this information through the representational state transfer-based web application programming interface in an automated manner.

Motion analysis of wheelchair propulsion movements in hemiplegic patients: effect of a wheelchair cushion on suppressing posterior pelvic tilt.

[Purpose] This study sought to ascertain whether, in hemiplegic patients, the effect of a wheelchair cushion to suppress pelvic posterior tilt when initiating wheelchair propulsion would continue in subsequent propulsions. [Subjects] Eighteen hemiplegic patients who were able to propel a wheelchair in a seated position participated in this study. [Methods] An adjustable wheelchair was fitted with a cushion that had an anchoring function, and a thigh pad on the propulsion side was removed. Propulsion movements from the seated position without moving through three propulsion cycles were measured using a three-dimensional motion analysis system, and electromyography was used to determine the angle of pelvic posterior tilt, muscle activity of the biceps femoris long head, and propulsion speed. [Results] Pelvic posterior tilt could be suppressed through the three propulsion cycles, which served to increase propulsion speed. Muscle activity of the biceps femoris long head was highest when initiating propulsion and decreased thereafter. [Conclusion] The effect of the wheelchair cushion on suppressing pelvic posterior tilt continued through three propulsion cycles.

Effect of heel pressure pad attached to ankle-foot orthosis on the energy conversion efficiency in post-stroke hemiplegic gait.

[Purpose] This study aimed to analyze the effect of heel pads in ankle-foot orthoses on dynamic motion aspects of gait in stroke patients from the viewpoint of energy conversion efficiency. [Subjects] Fourteen chronic stroke patients who were ambulatory and had lower extremity motor function categorized as Brunnstrom stage IV participated in the study. [Methods] A three-dimensional motion analysis system was used to assess the effect of heel pad intervention on dynamic motion gait parameters using a single-system A-B-A design. [Results] The results showed that a heel pad attached to the ankle-foot orthosis caused significant retention of the center-of-pressure at the heel during the heel rocker function and significant increase in the dorsiflexion moment and the height of the center of gravity. [Conclusion] The present study showed that a heel pad attached to the calcaneal region of an ankle-foot orthosis caused slight retention of the center-of-pressure at the heel during the heel rocker function along with center of gravity elevation in the stance phase and improved the energy conversion efficiency, especially on the non-paretic side.

Analysis of movements involved in raising lower garments during toileting in patients with stroke and hemiplegia: An analysis focused on manipulation on the paretic side.

BACKGROUND: Movements to raise lower garments in patients with stroke and hemiplegia consist of downward reach, non-paretic-side manipulation, and paretic-side manipulation. In this study, we focused on paretic-side manipulation, which is particularly difficult, and investigated the factors that make it challenging. METHODS: Forty-eight patients with stroke and hemiplegia (23 and 25 patients in independent and dependent groups, respectively) participated in this study. First, we investigated the difficulty of each manipulation using a visual analog scale to confirm the usefulness of focusing on paretic-side manipulation. Characteristics of the paretic side manipulation were compared between the dependent and independent groups using a three-dimensional motion analysis system. FINDINGS: The dependent group showed greater difficulty in manipulation on the paretic side compared to manipulation on the non-paretic side. The dependent group had a lower paretic limb loading ratio (p < 0.01), greater pelvic rotation angle (p < 0.01), and longer paretic side manipulation time (p < 0.01) than those in the independent group. INTERPRETATION: The factors that contributed to greater difficulty in manipulating the paretic side were a lower limb loading rate and larger pelvic rotation angle toward the paretic side. These factors make it difficult to reach the lower garment and result in inefficient manipulation of the paretic side.

CRYPTIC PRECOCIOUS/MED12 is a novel flowering regulator with multiple target steps in Arabidopsis.

The proper timing of flowering is of crucial importance for reproductive success of plants. Regulation of flowering is orchestrated by inputs from both environmental and endogenous signals such as daylength, light quality, temperature and hormones, and key flowering regulators construct several parallel and interactive genetic pathways. This integrative regulatory network has been proposed to create robustness as well as plasticity of the regulation. Although knowledge of key genes and their regulation has been accumulated, there still remains much to learn about how they are organized into an integrative regulatory network. Here, we have analyzed the CRYPTIC PRECOCIOUS (CRP) gene for the Arabidopsis counterpart of the MED12 subunit of the Mediator. A novel dominant mutant, crp-1D, which causes up-regulation of SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1), FRUITFULL (FUL) and APETALA1 (AP1) expression in a FLOWERING LOCUS T (FT)-dependent manner, was identified in an enhancer screen of the early-flowering phenotype of 35S::FT. Genetic and molecular analysis of both crp-1D and crp loss-of-function alleles showed that MED12/CRP is required not only for proper regulation of SOC1, FUL and AP1, but also for up-regulation of FT, TWIN SISTER OF FT (TSF) and FD, and down-regulation of FLOWERING LOCUS C (FLC). These observations suggest that MED12/CRP is a novel flowering regulator with multiple regulatory target steps both upstream and downstream of the key flowering regulators including FT florigen. Our work, taken together with recent studies of other Mediator subunit genes, supports an emerging view that the Mediator plays multiple roles in the regulation of flowering.

Therapeutic effect of gait training with two types of ankle-foot orthoses on the gait of the stroke patients in the recovery phase.

Objectives: This study aimed to demonstrate the therapeutic effect of gait training using ankle-foot orthoses (AFOs) on the gait of stroke patients when not wearing AFOs with two different types of AFO, an AFO with an oil damper (AFO-OD) that resists plantarflexion and an AFO with a plantarflexion stop (AFO-PS), and to display the possible differences between the AFO types. Patients and methods: Forty-two patients (38 males, 4 males, mean age: 59.7±10.9; range, 38 to 81 years) with subacute stroke were randomized to either an AFO-PS or an AFO-OD group. Participants were given gait training in a two-week period by physiotherapists wearing their allocated AFO. Nineteen patients were assigned to the AFO-PS group and 20 to the AFO-OD group. Patients' gait without an AFO before gait training and then after two weeks of training wearing allocated AFOs was recorded through a three-dimensional movement capture system. Results: A therapeutic effect through two weeks of continuous use of AFOs and gait training was found in both AFO groups (main effect of time) in the spatiotemporal factors, ankle joint moments, ankle power generation, shank-to-vertical angle, and center of gravity velocity throughout the stance phase, pre-swing knee angular velocity, and hip flexion moment in pre-swing. The results did not show a large interaction between two AFOs group. Conclusion: These findings reveal that both AFOs had significant therapeutic effects on stroke gait. There was no significant difference between the two AFO groups. Further studies with a control group representing the effects of gait training without wearing an AFO are needed.

Differences in mediolateral dynamic stability during gait initiation according to whether the non-paretic or paretic leg is used as the leading limb.

We investigated mediolateral dynamic stability at first foot off and first initial contact during gait initiation according to whether the paretic or non-paretic leg was used as the leading limb. Thirty-eight individuals with stroke initiated gait with the paretic and non-paretic legs as the leading limb, and their movements were measured using a 3D motion analysis system. Margin of stability (i.e., the length between the extrapolated center of mass and lateral border of the stance foot) was used as an index of dynamic stability, with a large value indicating dynamic stability in the lateral direction. However, an excessively large margin of stability value (i.e., when the extrapolated center of mass is outside the medial border of the stance foot) indicates dynamic instability in the medial direction. Differences in the margin of stability between tasks were compared using the Wilcoxon signed-rank test. The minimum margin of stability was observed just before first foot off. When the non-paretic leg was used as the leading limb, the margin of stability tended to be excessively large at first foot off compared with when the paretic leg was used (p < 0.001). In other words, the extrapolated center of mass was outside the medial border of the paretic stance foot. In conclusion, lateral stability was achieved when using the non-paretic leading limb because the extrapolated center of mass was located outside the medial border of the stance foot. However, medial dynamic stability was lower for the non-paretic leading limb compared with the paretic leading limb.

Effect of types of ankle-foot orthoses on energy expenditure metrics during walking in individuals with stroke: a systematic review.

PURPOSE: This systematic review is aimed at evaluating the efficacy of AFO types and comparison between them on the energy expenditure metrics of walking in individuals who had suffered a stroke with (sub)acute or chronic evolution. METHODS: The following databases were searched; PubMed, Scopus, ISI Web of Knowledge, Embase and Cochrane Library based on the population intervention comparison outcome (PICO) method. RESULTS: A total of 15 trials involving 195 participants were selected for the final evaluation. All trials, except one, examined individuals in chronic phase. Although the evidence from the selected studies was generally weak, the consensus was that an AFO may have a positive immediate effect on the energy expenditure metrics including energy cost, physiological cost index, mechanical work and vertical center of mass trajectory on the affected leg, in both overground walking and treadmill walking in adults with chronic stroke. There were insufficient studies to evaluate the medium term efficacy of wearing an AFO combined with gait training on metabolic cost parameters during ambulation. There were also insufficient studies for comparison among different designs of AFOs. CONCLUSIONS: An AFO can immediately improve energy expenditure metrics of walking in stroke survivors. There is a need for further well-designed randomized trials to evaluate long-term effect of gait training using AFOs and comparison among the different types of orthoses.IMPLICATIONS FOR REHABILITATIONAn AFO can immediately improve the energy expenditure metrics during walking after stroke.Measurement of energetic parameters of walking wearing a orthotic device such as an AFO can evaluate gait economy in stroke populations.

Differences in paretic lower limb loading and fluidity in sit-to-walk according to selection of the leading limb in individuals with stroke.

BACKGROUND: Sit-to-walk is an asymmetric task that is challenging for individuals with stroke, and paretic limb loading at seat-off and movement fluidity may change according to whether the non-paretic or paretic leg is used as the leading limb. This study aimed to investigate differences in paretic limb loading and fluidity depending on whether the non-paretic limb or paretic limb was used as the leading limb. METHODS: Thirty-eight individuals with stroke performed sit-to-walk with each leg as the leading limb, and their movements were measured using a 3D motion analysis system. The paired t-test or Wilcoxon signed-rank test was used to assess differences according to limb selection in paretic limb loading ratio at seat-off and fluidity (Fluidity Index: ratio of the lowest to peak forward velocity before first initial contact). FINDINGS: Twenty-two of 38 participants preferred to use the paretic limb as the leading limb. When leading with the paretic limb, the paretic limb loading ratio was significantly larger (p = 0.002), and the Fluidity Index was lower (p = 0.007). INTERPRETATION: Sit-to-walk with the paretic leading limb seems to be an adaptive movement because many participants preferred leading with the paretic limb. However, selection of the leading limb in sit-to-walk involves a biomechanical tradeoff between paretic limb loading at seat-off and movement fluidity in individuals with stroke. Use of the paretic leading limb requires loading capacity of this limb, and the non-paretic leading limb must have high balance ability to merge sit-to-stand and gait initiation.

Effect of ankle-foot orthoses on functional outcome measurements in individuals with stroke: a systematic review and meta-analysis.

PURPOSE: To determine and compare the effect of ankle-foot orthosis (AFOs) types on functional outcome measurements in individuals with (sub)acute or chronic stroke impairments. METHODS: PubMed, Web of Knowledge, Embase, Scopus, ProQuest, and Cochrane were searched from inception until September 2020. Methodological quality assessment of 30 studies was conducted based on the Downs and Black checklist. Functional indices were pooled according to their standardized mean difference (SMD) and 95% confidence intervals (CI) in a random-effect model. A narrative analysis was performed where data pooling was not feasible. RESULTS: Overall pooled results indicated improvements in favor of AFOs versus without for the Berg Balance Scale (SMD: 0.54, CI: 0.19-0.88), timed-up and go test (SMD: -0.45, CI: -0.67 to -0.24), Functional Ambulatory Categories (SMD: 1.72, CI: 1.25-2.19), 6-Minute Walking Test (SMD: 0.91, CI: 0.53-1.28), Timed Up-Stairs (SMD: -0.35, CI: -0.64 to 0.05), and Motricity Index (SMD: 0.65, CI: 0.38-0.92). Heterogeneity was non-significant for all outcomes (I2 < 50%, p > 0.05) except the Berg Balance Scale and Functional Ambulatory Categories. Additionally, there was not sufficient evidence to determine the effectiveness of specific orthotic designs over others. CONCLUSIONS: An AFO can improve ambulatory function in stroke survivors. Future studies should explore the long-term effects of rehabilitation using AFOs and compare differences in orthotic designs.IMPLICATIONS FOR REHABILITATIONAn AFO can improve functional performance and ambulation in survivors of strokes.Wearing an AFO in rehabilitation care during the subacute phase post stroke may have beneficial effects on functional outcomes measured.There was no evidence as to the effectiveness of specific AFO designs over others.

Abnormal Gait Movements Prior to a Near Fall in Individuals After Stroke.

OBJECTIVE: To investigate the abnormal kinematic and kinetic movements in the last gait cycle before a near fall in individuals poststroke, where a near fall is defined as a physical therapist feeling the need to stabilize a patient. DESIGN: Retrospective study. SETTING: A rehabilitation center. PARTICIPANTS: Twenty-five adults (22 men, 3 women; N=25) with an average age of 66.3 years and mean duration from stroke of 4 months who required manual assistance for a sudden imbalance during routine 3-dimensional motion analysis. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: We compared the averaged usual gait cycle and the last cycle before the near-falling gait cycle (pre-near-falling gait cycle). We obtained the following spatiotemporal parameters: gait velocity, gait cycle duration, mediolateral center of mass displacement, step length, step width, joint moments, and angular displacement of the trunk in a cycle. Peak values of joint moments and trunk angle displacement were calculated. RESULTS: Etiology for near falls included toe trip, mediolateral perturbation, and knee collapse. We found the following significant differences in the pre-near-falling gait cycle compared with the usual gait cycle: decreased gait velocity, prolonged total cycle time, and excessive mediolateral center of mass displacement. CONCLUSIONS: Decreased gait velocity, prolonged cycle time, and excessive mediolateral center of mass displacement may be a sign of an impending fall in people with impaired gait after stroke.

The effects of ankle-foot orthoses with plantar flexion stop and plantar flexion resistance using rocker-sole shoes on stroke gait: A randomized-controlled trial.

OBJECTIVES: This study aims to evaluate the effect of two ankle-foot orthoses (AFOs), AFO with plantar flexion stop (AFO-PlfS), and AFO with plantar flexion resistance (AFO-PlfR), while wearing standard shoes and rocker-sole shoes. PATIENTS AND METHODS: Between November 2017 and July 2018, in this randomized-controlled study, a total of 20 stroke patients (8 males, 12 females; mean age: 48.1 years; range, 33 to 65 years) in chronic phase were randomized to AFO groups (AFO-PlfS group, n=10 and AFO-PlfR group, n=10). Each group received the allocated AFO along with two kinds of shoes (standard shoe and rocker shoe) for a two-week adaptation. Two effects were separately evaluated: The orthotic effect and rocker shoe effect were defined as the evaluation of using an AFO wearing standard shoe compared to only standard shoe, and evaluation of using an AFO wearing rocker shoe compared to an AFO wearing standard shoe, respectively. The gait of each group was measured by three-dimensional motion analysis. RESULTS: A significant orthotic effect was found in both AFO groups in spatiotemporal parameters and maximum ankle dorsiflexion in the single-support phase. Additionally, the AFO-PlfR group showed a significant improvement in the parameters related to the first rocker of gait, but not for AFO-PlfS group concerning the orthotic effect. The rocker shoe effect was found in significant reduction of peak ankle plantar flexor moment and power ankle generation during preswing for both AFO groups. CONCLUSION: According to the orthotic effect, an AFO-PlfR can create better function in the improvement of parameters related to the first rocker. Although a rocker shoe can facilitate rollover for weight progression in the third rocker of gait, it cannot make a strong push-off function in stroke survivors.

Classification of abnormal gait patterns of poststroke hemiplegic patients in principal component analysis.

Motoya R, Yamamoto S, Naoe M, Taniguchi R, Kawahara A, Iwata T. Classification of abnormal gait patterns of poststroke hemiplegic patients in principal component analysis. Jpn J Compr Rehabil Sci 2021; 12: 70-77. Objective: The objective of this study was to classify the 10 types of characteristic abnormal gait by principal component analysis using quantitative indices of 10 types of abnormal gait. Methods: For abnormal gait pattern classification, principal component analysis was performed using the deviation values of the 10 types of abnormal gait of 90 subjects. Scatter plots of the factor loadings of the 1st and 2nd principal components of the 10 types of abnormal gait were prepared, and those arranged at near sites were grouped based on the positional relationship, through which abnormal gait patterns were classified. Results: It was suggested that abnormal gait patterns can be classified into insufficient knee flexion, hip hiking, and excessive lateral shift of the trunk over the unaffected side in the swing phase; knee extensor thrust pattern accompanying forefoot contact in the stance phase in addition to circumduction gait of the swing phase; and flexed knee gait pattern accompanying retropulsion of the hip in addition to median whip in the stance phase and excessive hip external rotation in the swing phase. Conclusions: It was clarified by these principal component analyses that information contained in the results of the 10 quantitative indices of abnormal gait of the 90 poststroke hemiplegia patients was compressed into several abnormal gait patterns. If observational abnormal gait analysis is performed after understanding this gait pattern classification, it may help improve the accuracy of gait analysis by observation.