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[Purpose] This study aimed to verify muscle activity patterns during posterior gait assistance with a knee-ankle-foot orthosis (KAFO) in patients with severe acute stroke hemiplegia and clarify its relationships with physical therapy parameters. [Participants and Methods] We measured activity in the rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius muscles in 30 patients with acute stroke during KAFO posterior gait assistance and examined their muscle activity patterns using the Japan Coma Scale (JCS), Brunnstrom Recovery Stage (BRS), Berg Balance Scale (BBS), Functional Movement Screen (FMS), and Functional Independence Measure (FIM). We divided lower extremity muscle activity into first and second half of the stance phase, compared muscle activity during the first half of the stance phase and the second half of the stance phase. In addition, the relationship between muscle activity during gaiting and each parameter was analyzed. [Results] All four muscles showed significantly higher values in the first half of the stance phase than in the second half of the stance phase. Rectus femoris first half of the stance phase muscle activity showed a moderate correlation with the BRS, BBS, and FMS scores. [Conclusion] The amount of gastrocnemius muscle activity when KAFO assists walking from behind increases in the latter half of stance in healthy individuals. However, in patients with stroke, the activity was lower and deviated from the gastrocnemius muscle activity during walking in healthy individuals.
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[Purpose] To develop a knee joint for knee-ankle-foot orthoses that is easy to operate and allows for four levels of knee-flexion-movement adjustment, and to determine the effects of different flexion ranges of motion on knee flexion angle during gait. [Participants and Methods] Participants were eight healthy adults. Knee joint for knee-ankle-foot orthoses were made for each participant, and the knee flexion angle during gait was measured for each of the four knee joint settings: fixed in extension, 15° flexion range, 30° flexion range, and free flexion. [Results] Gait analysis showed that the knee flexion angle in the loading response phase was significantly greater in the 15° flexion range, 30° flexion range, and free-flexion settings than in the fixed-in-extension setting. While in the swing phase, the angle was greatest in the fixed setting, followed by the 15° flexion, 30° flexion, and free settings. [Conclusion] The proposed knee joint, when used in post-stroke gait practice using knee-ankle-foot orthoses, allows the gradual increase in the flexion range of motion of the joint as the weight-bearing capability of the lower limb improves, which would enable task-oriented practice similar to walking with ankle-foot orthoses as the next-stage target movement.
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OBJECTIVES: Knee-ankle-foot orthosis (KAFO) is sometimes used for gait training in stroke patients. The impact of the time of wearing KAFO on activities of daily living (ADL) recovery has not been clarified. This study aimed to examine the relationship between the days from onset to KAFO wearing and functional prognosis in patients after stroke. MATERIALS AND METHODS: This retrospective, observational study was conducted with stroke patients who were prescribed a KAFO. Patients were divided into early and delayed groups according to the median days from onset to KAFO wearing. Baseline characteristics were evaluated at the initiation of KAFO wearing. The primary outcome was the Functional Independence Measure (FIM) gain, which was scored by the nurse at baseline and discharge. RESULTS: 112 participants (mean age 67.9 ± 14.0 years, 51.8% male) were included. The time period measure from day of onset to KAFO wearing for the early group was significantly shorter than the delayed group (35.8 ± 6.6 days vs. 73.5 ± 28.9 days). The early group had a higher FIM at discharge (84.9 ± 28.0% vs. 65.1 ± 29.0%, P < 0.001) and higher FIM gain (36.9 ± 19.8% vs. 26.8 ± 22.3, P = 0.013) than did the delayed group. Multiple regression analysis showed that the early group was associated with FIM gain (coefficient = 8.607, P = 0.032). CONCLUSIONS: Early wearing of KAFO, irrespective of the difference in ADL at the time of KAFO wearing, may have a positive impact on the improvement of ADL in patients after stroke.
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Aparatos Ortopédicos , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Anciano , Anciano de 80 o más Años , Tobillo/fisiología , Femenino , Pie/fisiología , Ortesis del Pié , Estado Funcional , Humanos , Rodilla/fisiología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Accidente Cerebrovascular/fisiopatología , Factores de TiempoRESUMEN
[Purpose] We aimed to evaluate knee joint movement and muscle activity ratio changes in stroke hemiplegic patients in recovery phase after using a knee-ankle-foot orthosis with an adjustable knee joint for 1 month; we also aimed to discuss the practical implications of our findings. [Participants and Methods] The participants were 8 hemiplegic patients in the recovery phase of stroke who were prescribed knee-ankle-foot orthosis with adjustable knee joint. We measured knee joint angles and electromyographic activity of the vastus medialis and biceps femoris during walking in two conditions: the knee-ankle-foot orthosis knee joint fixed in the extended position and the knee joint moved from 0° to 30° in the flexion direction. Measurements were taken 2 weeks after completion to account for habituation of the orthosis and repeated 1 month later. [Results] When the knee joint was moving from 0° to 30° in the flexion direction, the knee joint angle at initial contact and the minimum flexion angle of the gait cycle decreased significantly between the first and second measurements. When knee joint flexion was 30°, the muscle activity ratio of the vastus medialis increased significantly in the loading response and mid-stance compared to when it was fixed. [Conclusion] Setting the knee joint of a knee-ankle-foot orthosis in accordance with the knee joint movement may increase the muscle activity ratio of the vastus medialis from loading response to mid-stance.
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BACKGROUND: Functionality and versatility of microprocessor-controlled stance-control knee-ankle-foot orthoses (M-SCKAFO) are dictated by their embedded control systems. Proper gait phase recognition (GPR) is required to enable these devices to provide sufficient knee-control at the appropriate time, thereby reducing the incidence of knee-collapse and fall events. Ideally, the M-SCKAFO sensor system would be local to the thigh and knee, to facilitate innovative orthosis designs that allow more flexibility for ankle joint selection and other orthosis components. We hypothesized that machine learning with local sensor signals from the thigh and knee could effectively distinguish gait phases across different walking conditions (i.e., surface levels, walking speeds) and that performance would improve with gait phase transition criteria (i.e., current states depend on previous states). METHODS: A logistic model decision tree (LMT) classifier was trained and tested (five-fold cross-validation) on gait data that included knee flexion angle, thigh-segment angular velocity, and thigh-segment acceleration. Twenty features were extracted from 0.1 s sliding windows for 30 able-bodied participants that walked on different surfaces (level, down-slope, up-slope, right cross-slope, left cross-slope) at a various walking speeds (self-paced (1.33 m/s, SD = 0.04 m/s), 0.8, 0.6, 0.4 m/s). The LMT-based GPR model was also tested with another validation set containing similar features and surfaces from 12 able-bodied volunteers at self-paced walking speeds (1.41 m/s, SD = 0.34 m/s). A "Transition Sequence Verification and Correction" (TSVC) algorithm was applied to correct for continuous class prediction and to improve GPR performance. RESULTS: The LMT had a tree size of 1643 with 822 leaf nodes, with a logistic regression model at each leaf node. The local sensor LMT-based GPR model identified loading response, push-off, swing, and terminal swing phases with overall classification accuracy of 98.38 for the initial training set (five-fold cross-validation) and 90.60% for the validation set. Applying TSVC increased classification accuracy to 98.72% for the initial training set and 98.61% for the validation set. Sensitivity, specificity, precision, F-score, and Matthew's correlation coefficient results suggest strong evidence for the feasibility of an LMT-based GPR system for real-time orthosis control. CONCLUSIONS: The novel machine learning GPR model that used sensor features local to the thigh and knee was viable for dynamic knee-ankle-foot orthosis-control. This highly accurate GPR model was generalizable when combined with TSVC. Our approach could reduce sensor system complexity as compared with other M-SCKAFO approaches, thereby enabling customizable advantages for end-users through modular unit orthosis designs.
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Árboles de Decisión , Marcha/fisiología , Aparatos Ortopédicos , Diseño de Prótesis , Algoritmos , Fenómenos Biomecánicos , Trastornos Neurológicos de la Marcha , Humanos , Rodilla , Modelos Logísticos , Aprendizaje Automático , Análisis de Regresión , Muslo , CaminataRESUMEN
[Purpose] The purpose of this study was to evaluate the early effects of a knee-ankle-foot orthosis on static standing balance in people with subacute stroke. [Participants and Methods] Timed static standing balance in four standing conditions (feet apart with eyes open, feet apart with eyes closed, feet together with eyes open, and tandem stance with eyes open) was assessed in 29 inpatients (mean age: 67.3 ± 13.3â years) with subacute stroke with and without a knee-ankle-foot orthosis on the paretic lower limb. [Results] In the group of participants who were unable to stand without a knee-ankle-foot orthosis, the proportion of participants who were able to stand with a knee-ankle-foot orthosis was significantly increased in the following conditions: feet apart with eyes open and feet apart with eyes closed. In the group of participants who were able to stand without a knee-ankle-foot orthosis, the mean duration of time for which the participants with a knee-ankle-foot orthosis were able to stand was significantly longer than that for those without a knee-ankle-foot orthosis for all standing conditions. [Conclusion] A knee-ankle-foot orthosis may be a useful assistive device to support static standing balance for people with subacute stroke.
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This case report provides insights into the physiotherapy management of a 12-year-old male with Duchenne muscular dystrophy (DMD). DMD is a devastating genetic disorder characterized by progressive muscle degeneration and weakness. Skeletal muscle degeneration is induced by a genetic disorder. It is a common X-linked condition that causes hypertrophy of the calves and proximal muscular weakness in children. It frequently results in early mortality, wheelchair confinement, and delays in motor development. Physiotherapy interventions aim to optimize functional abilities and quality of life in individuals with DMD. This case report highlights the effectiveness of physiotherapy in managing DMD progression. This study presents a case exhibiting notable clinical symptoms, highlighting the urgency for advanced treatments to combat this debilitating disease. Outcome measures such as body mass index, spirometry, manual muscle testing, and the World Health Organization Quality-of-Life scale are used to report patient progress. The treatment plan was carried out for six weeks, five times a week. Physiotherapy strategies include diet management, stretching and splinting techniques, and pulmonary training. While current treatments focus on symptom management, ongoing research holds promise for the development of more effective therapies to improve outcomes and quality of life for affected individuals. Multidisciplinary care, including neurophysiotherapy rehabilitation, plays a crucial role in managing the symptoms and complications of DMD, emphasizing the importance of comprehensive support for patients and their families. At the end of our rehabilitation, the patient showed significant improvement in the outcome measures.
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Introduction: Lower limb orthoses (LLOs) and assistive devices (ADs) can be used together or separately to improve mobility when performing daily activities. The goal of this study was to examine utilization of LLOs and ADs in a national sample of adult LLO users. Methods: A survey was designed to ask participants whether they typically use their LLOs and/or ADs to perform 20 daily activities. LLO users from orthotic clinics across the United States were invited to complete the survey. Descriptive statistics were used to examine utilization trends. Results: Survey responses from 1036 LLO users were analyzed. Community-based activities were performed with LLOs by at least 80% of participants. Activities that involved walking short distances in the home were more often performed without LLOs or ADs. Among participants with the four most prevalent health conditions, LLO use in the community was greatest among participants with Charcot-Marie-Tooth disease. Conclusions: LLOs were frequently used for a wide range of community-based activities. Simultaneous use of ADs and LLOs may be most beneficial for LLO users when performing activities outside of the home. Clinicians can discuss LLO and AD use with patients to optimize their functional outcomes at home and in the community.
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Introduction: The C-Brace microprocessor-controlled stance and swing control orthosis has been shown to improve function, mobility, and quality of life. A systematic registry to gather long-term, real-world safety and effectiveness data in patients fit with a C-Brace has not been performed. Methods: International multicenter registry. Patients undergoing routine C-Brace fittings were assessed at baseline and 1 year after fitting. Primary outcomes were fast walking speed (FWS) measured by 25-foot or 10-meter walk test, Timed Up and Go (TUG) and the Activity-specific Balance Confidence (ABC) Scale. Secondary and exploratory outcomes included the Patient-specific Functional Scale (PSFS), falls, pain, PROMIS Pain Interference (PI), and quality of life. Results: 48 subjects with 1-year baseline and follow up data were analyzed. With the C-Brace, FWS improved by + 0.26 ± 0.33 m/s (p < .0001), TUG by -8.1 ± 14.6 sec (p < .0001), and ABC by + 24.9 ± 25.8% (p < .0001). Mean falls reduced from 33 ± 77 to 3.0 ± 5.6 (p = .0005). PSFS increased by 3.60 ± 2.34 points (p < .0001). Outcomes for pain, PI and quality of life showed significant improvements with the C-Brace. Conclusion: The C-Brace is an effective option to improve safety, mobility, and quality of life for patients needing a KAFO for ambulation.
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Introduction: A knee-ankle-foot orthosis (KAFO) prevents knee buckling during walking and enables gait training for acute hemiplegic stroke patients with severe gait disturbances. Although the goal of gait training with a KAFO is to improve gait ability, that is, to acquire walking with an ankle-foot orthosis (AFO), it is not clear how gait training with a KAFO contributes to improving gait ability. Therefore, this study aimed to investigate the relationship between muscle activities during walking with a KAFO and the improvement of gait ability in hemiplegic stroke patients with severe gait disturbance. Methods: A prospective cohort study was conducted. Fifty acute hemiplegic stroke patients who could not walk with an AFO participated. Muscle activities of the paretic rectus femoris, biceps femoris, tibialis anterior, and soleus were assessed with surface electromyogram during walking with a KAFO. Electromyograms were assessed at the beginning of gait training and at the time the Ambulation Independence Measure score improved by 3 or higher, or discharge. Results: Even in patients with complete hemiplegia, paretic rectus femoris, biceps femoris, and soleus showed periodic muscle activity during walking with a KAFO. Twenty-three patients improved to an Ambulation Independence Measure score of 3 or higher and were able to walk with an AFO (good recovery group). At the beginning of gait training, paretic rectus femoris muscle activity during the first double-limb support phase was significantly higher in the good recovery group than in the poor recovery group. The rectus femoris muscle activity significantly increased from before to after acute rehabilitation, which consisted mainly of gait training with a KAFO. Discussion: For acute hemiplegic stroke patients with severe disturbance, the induction and enhancement of paretic quadriceps muscle activity during walking with a KAFO play an important role in acquiring walking with an AFO.
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BACKGROUND: Accurate prediction of recovery is essential to determine whether a knee-ankle-foot orthosis (KAFO) is required in the subacute phase of stroke. However, there are currently no reliable methods to predict such recovery. OBJECTIVE: This study aimed to determine whether muscle strength of the affected lower limb (affected side LL strength) in stroke patients in the subacute phase who cannot walk without a KAFO can be used to predict the continuous need for a KAFO, using a hand-held dynamometer. METHODS: We enrolled patients with severe hemiplegia (nâ=â51) who were unable to walk without a KAFO for 10 days after stroke onset. They were divided into two groups depending on the continuous need for a KAFO at 1 month after onset; the KAFO and non-KAFO groups. Logistic regression analysis was used to investigate whether the affected side LL strength was a predictor of the continuous need for a KAFO at 1 month after onset. In addition, significant predictors were analyzed using receiver operating characteristic (ROC) curves. RESULTS: The KAFO and non-KAFO groups included 23 (45.10%) and 28 (54.90%) patients, respectively. The affected side LL strength and pusher syndrome severity were identified as predictors of the continuous need for a KAFO. The predictor with the highest predictive ability was the affected side LL strength, with an area under the ROC curve of 0.80 (95% CI, 0.68-0.93). CONCLUSIONS: Affected side LL strength may be a highly accurate predictor of the need for a KAFO in the subacute phase of stroke.
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Hemiplejía , Accidente Cerebrovascular , Humanos , Extremidad Inferior , Fuerza Muscular , Aparatos Ortopédicos , Accidente Cerebrovascular/complicacionesRESUMEN
Kikkawa T, Takashima A. Practice of gait training using lower-limb orthosis and body weight-supported walker for severe acute motor axonal neuropathy: a case report. Jpn J Compr Rehabil Sci 2023; 14: 49-53. Introduction: Acute motor axonal neuropathy (AMAN) requires aggressive gait rehabilitation from the early phase of its onset due to the long time required to achieve independent gait. In this report, we describe the progress of gait training using a combination of lower-limb orthosis and body weight-supported (BWS) walker in a patient with severe AMAN. Case: A 30-year-olds man diagnosed with AMAN underwent two high-dose intravenous immunoglobulin treatments and combined steroid pulse therapy. The patient was admitted to the convalescent rehabilitation ward for 87 days with a Medical Research Council (MRC) score of 7 points for muscle strength and 13 points for Functional Independence Measure (FIM) motor items. He started gait training with a knee-ankle-foot orthosis on the 128th day. Thereafter, the distance of gait training increased with the use of lower-limb orthosis and BWS walker. At the time of discharge, the patient's MRC score had improved to 24 points and his FIM motor items score to 31 points. He was able to walk 90 m using ankle-foot orthosis and forearm walker and was transferred to a rehabilitation facility on day 237. Discussion: Gait training with lower-limb orthosis and BWS walker was performed on a patient with severe AMAN. As a result, gait training distance increased without adverse events. Gait training can be performed safely and effectively by combining lower-limb orthosis and BWS walker when gait ability is expected to improve, even in severely ill patients.
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INTRODUCTION: The C-Brace microprocessor stance and swing control orthosis was designed to overcome safety and functional limitations of traditional knee-ankle-foot orthoses (KAFOs) for individuals with lower limb paresis. However, a systematic comparison to established KAFO types has not been performed in a bigger sample. METHODS: International multicenter, randomized, controlled, cross-over clinical trial. Legacy KAFO users at risk of falling were randomized to KAFO/C-Brace or C-Brace/KAFO use for three months with each orthosis. Primary outcome was balance assessed with the Berg Balance Scale (BBS). Secondary outcomes were falls, mobility, function, and quality of life. RESULTS: Intention-to-treat analysis with 102 participants. With the C-Brace, the BBS improved by 3.3 ± 6.3 points (p < 0.0001). Significantly fewer participants presented BBS scores <40 indicative of increased fall risk (16 vs. 36, p = 0.018). Mean falls reduced from 4.0 ± 16.8 to 1.1 ± 3.3 (p = 0.002). Outcomes for function, mobility, and quality of life showed significant improvements with the C-Brace. DISCUSSION: The improvements in fall risk and mobility can be attributed to the stumble recovery and controlled knee flexion during weight bearing of the C-Brace and have a positive impact on the quality of life of users. CONCLUSION: The C-Brace represents an option for KAFO users with increased fall risk and reduced mobility.
When prescribing traditional knee-ankle-foot orthoses (KAFOs), their known limitations, such as limited function and mobility, and the requirement to walk with compensatory mechanisms, especially on non-level terrains, should be considered.For patients with compromised balance and increased risk of falling when using a traditional KAFO, a microprocessor stance and swing control orthosis (MP-SSCO) may be considered as an orthotic option to reduce their fall risk.For patients with mobility restrictions using a traditional KAFO, a MP-SSCO may be considered to improve function, mobility, reintegration into normal living, and quality of life.
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A knee ankle foot orthosis (KAFO) may be prescribed to the person with severe neuromusculoskeletal impairment of the lower limb to promote walking stability. The locked knee ankle foot orthosis (L-KAFO) is among the KAFO's routinely prescribed; however, long-term use of the L-KAFO is associated with musculoskeletal (arthrogenic and myogenic) and integumentary changes, and gait asymmetry with increased energy expenditure. Consequently, the risk of developing low back pain, osteoarthritis of the lower limbs and spinal joints, skin dermatitis, and ulceration increases, all of which impact quality of life. This article synthesizes the iatrogenic biomechanical and physiological perils of long-term L-KAFO use. It promotes using recent advances in rehabilitation engineering to improve daily activities and independence for proper patient groups.
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Objectives: The Ponseti method has led to vast improvements in outcomes for infants born with clubfoot deformity, but challenges with compliance during the bracing phase of the protocol remain. Unilateral braces promise higher compliance but often have led to unacceptably high recurrence. Methods: We have developed a novel unilateral brace for clubfoot deformity that strategically applies patient-specific, anatomically-targeted forces to the lower limb to maintain correction. We retrospectively reviewed the cases of 26 patients with minimum follow-up of 24 months. The data were analyzed for recurrence rates, caregiver-reported compliance, and differences in Pirani score, dorsiflexion, abduction, hindfoot eversion, and resting rotation between initial and final follow-up. Results: Most patients (N = 23, 88%) were compliant with the bracing protocol. Two patients showed recurrence of deformity (8%). There were statistically significant improvements in Pirani score, dorsiflexion, abduction, hindfoot eversion, and resting external rotation. A subset of patients with sub-optimal correction at baseline showed improvement in all parameters across the course of bracing. Conclusions: This novel unilateral brace for maintenance of clubfoot correction after Ponseti treatment demonstrates rates of recurrence rates and caregiver-reported compliance at 2 years of follow up that are comparable to outcomes with traditional bilateral foot abduction orthoses.
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Impairments resulting from stroke lead to persistent difficulties with walking. Subsequently, an improved walking ability is one of the highest priorities for people living with stroke. The degree to which gait can be restored after a stroke is related to both the initial impairment in walking ability and the severity of paresis of the lower extremities. However, there are some patients with severe motor paralysis and a markedly disrupted corticospinal tract who regain their gait function. Recently, several case reports have described the recovery of gait function in stroke patients with severe hemiplegia by providing alternate gait training. Multiple studies have demonstrated that gait training can induce "locomotor-like" coordinated muscle activity of paralyzed lower limbs in people with spinal cord injury. In the present review, we discuss the neural mechanisms of gait, and then we review case reports on the restoration of gait function in stroke patients with severe hemiplegia.
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Recurvatum is defined as hyperextension of the knee in the stance phase of gait. Recurvatum knee is a naturally occurring common gait deviation in those with cerebral palsy, along with crouch knee, jump knee, and stiff knee gaits. Early and late recurvatum occur in the first and second halves of stance. Early recurvatum is associated with dynamic calf contraction that raises the heel and pushes the knee into hyperextension as the forefoot contacts the floor. Late recurvatum occurs after the foot is already flat on the floor. As the body weight comes forward over the foot, the tibia stops its forward motion too early as the ankle comes to its range-of-motion limit. The advancing body then moves forward over a hyperextending knee. Surgical hamstring lengthening can have recurvatum as a side effect. There are several strategies to decrease this risk. Medial hamstring lengthening may be safer than combined medial and lateral lengthening. The concept here is that less lengthening or less aggressive lengthening means less recurvatum risk. However, combined medial and lateral lengthening can be reasonably safe from the risk of causing recurvatum if the knee is showing enough preoperative flexion in stance to warrant the increased surgery. More flexion in stance relates to less risk, while less flexion in stance relates to more risk. Knee flexion in stance can be measured. This is done by measuring knee flexion at initial contact and knee flexion in stance in a gait lab or with stop-action video. If there is minimal knee flexion in stance, hamstring lengthening might not be advisable, even if the hamstrings are tight on popliteal angle testing. There are other factors that contribute to recurvatum risk, such as knee hyperextension on static exam, equinus contracture, and jump knee gait. For treatment of recurvatum, the mainstay is the use of ankle foot orthoses set in dorsiflexion. Surgical equinus correction in those with early stance recurvatum can be effective but it is not likely to be effective in those with late stance recurvatum.
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Murayama M. Effectiveness of a knee-ankle-foot orthosis with a knee extension aid in gait training for stroke patients. Jpn J Compr Rehabil Sci 2021; 12: 32-37. Objective: To evaluate the effectiveness of a knee-ankle-foot orthosis (KAFO) with a newly developed knee extension aid in gait training for stroke patients with severe leg paralysis. Methods: The participants were 7 recovering stroke patients prescribed a KAFO. With the KAFO knee joint set to allow free flexion, knee flexion angle, lower limb muscle activity, and time of plantar ground contact were measured during assisted walking with the knee extension aid or a conventional support loop. Results: When first using the knee extension aid, knee flexion angle at initial ground contact was significantly decreased and time from heel strike on the paralyzed side to forefoot strike was prolonged compared with the support loop. After using the knee extension aid for 1 week, in addition to the two parameters above, maximum knee flexion angle during the swing phase, knee extension displacement from the maximum flexion angle to initial ground contact, and the muscle activity ratio of the biceps femoris during the swing phase were significantly increased compared with the support loop. Conclusion: This knee extension aid may be indicated for patients who have difficulty in initial heel strike due to excessive knee flexion at the end of the swing phase.
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Gait restoration of individuals with spinal cord injury can be partially achieved using active orthoses or exoskeletons. To improve the walking ability of each patient as much as possible, it is important to personalize the parameters that define the device actuation. This study investigates whether using an optimal control-based predictive simulation approach to personalize pre-defined knee trajectory parameters for an active knee-ankle-foot orthosis (KAFO) used by spinal cord injured (SCI) subjects could potentially be an alternative to the current trial-and-error approach. We aimed to find the knee angle trajectory that produced an improved orthosis-assisted gait pattern compared to the one with passive support (locked knee). We collected experimental data from a healthy subject assisted by crutches and KAFOs (with locked knee and with knee flexion assistance) and from an SCI subject assisted by crutches and KAFOs (with locked knee). First, we compared different cost functions and chose the one that produced results closest to experimental locked knee walking for the healthy subject (angular coordinates mean RMSE was 5.74°). For this subject, we predicted crutch-orthosis-assisted walking imposing a pre-defined knee angle trajectory for different maximum knee flexion parameter values, and results were evaluated against experimental data using that same pre-defined knee flexion trajectories in the real device. Finally, using the selected cost function, gait cycles for different knee flexion assistance were predicted for an SCI subject. We evaluated changes in four clinically relevant parameters: foot clearance, stride length, cadence, and hip flexion ROM. Simulations for different values of maximum knee flexion showed variations of these parameters that were consistent with experimental data for the healthy subject (e.g., foot clearance increased/decreased similarly in experimental and predicted motions) and were reasonable for the SCI subject (e.g., maximum parameter values were found for moderate knee flexion). Although more research is needed before this method can be applied to choose optimal active orthosis controller parameters for specific subjects, these findings suggest that optimal control prediction of crutch-orthosis-assisted walking using biomechanical models might be used in place of the trial-and-error method to select the best maximum knee flexion angle during gait for a specific SCI subject.
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BACKGROUND: The quality of life (QoL) for patients with spinal cord injuries (SCI) is lower than that for healthy individuals. The main purpose of prescribing orthoses for these individuals is to improve their mobility and QoL. The hip knee ankle foot orthosis (HKAFO) has been the conventional choice for such patients, whilst the reciprocating gait orthosis (RGO) is a more contemporary option. Although the impact of these two types of orthoses on the biomechanics of walking has been previously evaluated in patients with SCI, there has been no specific comparison of their relative effects on QoL. OBJECTIVES: This study aimed to evaluate the Sickness Impact Profile (SIP-68) QoL questionnaire's total score and its sub-scores in patients with SCIs wearing either RGOs or HKAFOs. METHODS: This study was performed on 22 participants (11 participants wearing RGOs and 11 wearing HKAFOs). QoL scores were evaluated in each group of patients using the total and sub-scores from the SIP-68 questionnaire. RESULTS: There were no significant differences in the total SIP-68 scores between the RGO and HKAFO groups (p = .57). However, emotional stability and emotional independence sub-scores were significantly lower for the RGO users than for the HKAFO users (p = .03 and p = .01), respectively. CONCLUSIONS: Based upon this preliminary study, participants wearing RGOs or HKAFOs had similar QoL scores. However, those wearing RGOs may experience better emotional stability, communication, and emotional independence. This preliminary study does not provide definite conclusions since a large randomized control trial is required to compare the effects of these orthoses on the QoL scores in patients with SCIs.Implications for rehabilitationOur main aim in the current investigation was to shed light on the question that does the biomechanical superiority of the RGO to the HKAFO leads to better quality of life in SCI subjects who are using RGO. Regarding the fact that the primary goal of rehabilitation of people with SCI is to improve their quality of life, it seems that the more complicated newer orthosis (RGO) has no difference with the older type (HKAFO) in achieving the rehabilitation goals. More studies will in fact be necessary to find a definitive answer for this important question.According to the findings of our study, it seems to be more appropriate to prescribe RGO for male participants with higher body weight.