Initial Double Support Research Articles

Impact of deep brain stimulation on gait in Parkinson disease: A kinematic study

BackgroundThe effect of Deep Brain Stimulation (DBS) on gait in Parkinson’s Disease (PD) is poorly understood. Kinematic studies utilizing quantitative gait outcomes such as speed, cadence, and stride length have shown mixed results and were done mostly before and after acute DBS discontinuation. ObjectiveTo examine longitudinal changes in kinematic gait outcomes before and after DBS surgery. MethodWe retrospectively assessed changes in quantitative gait outcomes via motion capture in 22 PD patients before and after subthalamic (STN) or globus pallidus internus (GPi) DBS, in on medication state. Associations between gait outcomes and clinical variables were also assessed. ResultGait speed reduced from 110.7 ± 21.3 cm/s before surgery to 93.6 ± 24.9 after surgery (7.7 ± 2.9 months post-surgery, duration between assessments was 15.0 ± 3.8 months). Cadence, step length, stride length, and single support time reduced, while total support time, and initial double support time increased. Despite this, there was overall improvement in the Movement Disorder Society-Unified Parkinson Disease Rating Scale-Part III score “on medication/on stimulation” score (from 19.8 ± 10.7–13.9 ± 8.6). Change of gait speed was not related to changes in levodopa dosage, disease duration, unilateral vs bilateral stimulation, or target nucleus. ConclusionQuantitative gait outcomes in on medication state worsened after chronic DBS therapy despite improvement in other clinical outcomes. Whether these changes reflect the effects of DBS as opposed to ongoing disease progression is unknown.

Exploring Teslasuit's Potential in Detecting Sequential Slip-Induced Kinematic Changes among Healthy Young Adults.

This study aimed to assess whether the Teslasuit, a wearable motion-sensing technology, could detect subtle changes in gait following slip perturbations comparable to an infrared motion capture system. A total of 12 participants wore Teslasuits equipped with inertial measurement units (IMUs) and reflective markers. The experiments were conducted using the Motek GRAIL system, which allowed for accurate timing of slip perturbations during heel strikes. The data from Teslasuit and camera systems were analyzed using statistical parameter mapping (SPM) to compare gait patterns from the two systems and before and after slip. We found significant changes in ankle angles and moments before and after slip perturbations. We also found that step width significantly increased after slip perturbations (p = 0.03) and total double support time significantly decreased after slip (p = 0.01). However, we found that initial double support time significantly increased after slip (p = 0.01). However, there were no significant differences observed between the Teslasuit and motion capture systems in terms of kinematic curves for ankle, knee, and hip movements. The Teslasuit showed promise as an alternative to camera-based motion capture systems for assessing ankle, knee, and hip kinematics during slips. However, some limitations were noted, including kinematics magnitude differences between the two systems. The findings of this study contribute to the understanding of gait adaptations due to sequential slips and potential use of Teslasuit for fall prevention strategies, such as perturbation training.

The contribution of walking speed versus recent stroke to temporospatial gait variability

BackgroundInconsistent results have been reported for temporospatial gait variability after stroke. Given the large differences in gait speed across stroke subjects and relative to healthy controls, it is not clear which changes in temporospatial gait variability can be ascribed to the walking speed during gait evaluation versus the consequences of stroke. Research questionsDoes temporospatial gait variability differ between (1) stroke subjects grouped in clinically-relevant functional ambulation classes, (2) the paretic and non-paretic legs within each class, and (3) stroke and healthy subjects after controlling for gait speed? MethodsStroke subjects were evaluated at their comfortable speed < 2 months post-onset and classified into the household (<40 cm/s, n = 38), limited-community (40–80 cm/s, n = 35), and full-community (>80 cm/s, n = 14) walkers. Coefficients of variation (CVs) for paretic and non-paretic stance, initial double-support, and single-support times, step length, step cadence, and step width were compared across the stroke ambulation classes and between the two legs. For the parameters with significantly different CVs between stroke subjects and 33 age-matched controls walking at very-slow and free speeds, a 1-way ANCOVA was used with the gait speed as a covariate. ResultsFor most step parameters, CVs were greater in slower stroke ambulation classes except for the smaller step width CV. The differences between the paretic and non-paretic legs emerged in slower walkers only. After controlling for the gait speed, CVs of stroke subjects no longer significantly differed from controls walking at very-slow speed. With controls walking at free speed, however, CVs for the paretic and non-paretic single-support times and the non-paretic step time remained significantly different. SignificanceGait is more variable at slower speeds both in stroke subjects and healthy controls. After accounting for the free gait speed, the increased variability of only a few temporal parameters may be attributed to a recent stroke.

Study of the differences in the gait parameters of healthy and diseased limbs in patients with knee osteoarthritis

Knee osteoarthritis is a prevalent condition that affects millions of people worldwide. It is a degenerative disease that occurs when the protective cartilage in the knee joint wears down over time, leading to pain, stiffness, and swelling in the knee. The actuality of knee osteoarthritis lies in its high prevalence, significant healthcare costs, and impact on quality of life. The article presents the results of the study of the difference in gait parameters of healthy and diseased limbs in patients with knee osteoarthritis. Twenty patients were examined. The diagnosis of knee osteoarthritis was established according to the criteria of the American College of Rheumatology. Gait parameters were studied using the GAITRite® system. The following parameters were studied: Temporal Definitions (Step Time, Gait Cycle Time, Single Support, Initial Double Support, Stance); Spatial Parameters and Definitions (Step Length, Stride Length, H-H Base of Support, Toe In / Toe Out). Among the investigated indicators, two demonstrated reliable differences between healthy and diseased limbs. It was found that Step Time for diseased limb was statistically significantly greater than for the opposite limb. At the same time, the foot support time of the healthy limb and, accordingly, the Initial Double Support indicator statistically significantly exceeded the similar indicators for the diseased limb. Summarizing the results of еру study, it can be stated that patients with knee osteoarthritis have a gait disorder in the form of asymmetric steps. Thus, the time of support on the foot decreases, and accordingly, the time of transferring the foot of the diseased limb increases. Changes in the diseased limb are also reflected in the opposite, healthy limb. An effort to increase the speed of movement during the examination causes an increase in movement on a relatively healthy limb in the form of an increase in the length of the step and a reduction in the time of transfer of the foot of the diseased limb. Keywords: knee joint; osteoarthritis; gait parameters; GAITRite.

Frequency‐dependent modulation of neural oscillations across the gait cycle

Balance and walking are fundamental to support common daily activities. Relatively accurate characterizations of normal and impaired gait features were attained at the kinematic and muscular levels. Conversely, the neural processes underlying gait dynamics still need to be elucidated. To shed light on gait‐related modulations of neural activity, we collected high‐density electroencephalography (hdEEG) signals and ankle acceleration data in young healthy participants during treadmill walking. We used the ankle acceleration data to segment each gait cycle in four phases: initial double support, right leg swing, final double support, left leg swing. Then, we processed hdEEG signals to extract neural oscillations in alpha, beta, and gamma bands, and examined event‐related desynchronization/synchronization (ERD/ERS) across gait phases. Our results showed that ERD/ERS modulations for alpha, beta, and gamma bands were strongest in the primary sensorimotor cortex (M1), but were also found in premotor cortex, thalamus and cerebellum. We observed a modulation of neural oscillations across gait phases in M1 and cerebellum, and an interaction between frequency band and gait phase in premotor cortex and thalamus. Furthermore, an ERD/ERS lateralization effect was present in M1 for the alpha and beta bands, and in the cerebellum for the beta and gamma bands. Overall, our findings demonstrate that an electrophysiological source imaging approach based on hdEEG can be used to investigate dynamic neural processes of gait control. Future work on the development of mobile hdEEG‐based brain–body imaging platforms may enable overground walking investigations, with potential applications in the study of gait disorders.

Effects of Swedish massage on gait spatiotemporal parameters in adult women with medial knee osteoarthritis: A randomized controlled trial

BackgroundPatients with knee osteoarthritis (OA) are always faced with functional limitations in daily activities due to knee pain. They are also at risk of falling because of compensatory kinetics and kinematics changes in walking, which is why they are seeking complementary therapies to deal with their problems. ObjectiveThe present research aimed to evaluate whether Swedish massage is effective in relieving the symptoms of knee OA and improving the gait spatiotemporal parameters of patients with knee OA. MethodsThirty adult women with knee OA participated in this study voluntarily. The intervention group (n = 15) received Swedish massage on their quadriceps for 20–30 min per session (12 sessions). During this period, the control group (n = 15) received their regular treatment. Osteoarthritis symptoms were evaluated by the Western Ontario and McMaster Universities Osteoarthritis Index. The spatiotemporal parameters of gait were also captured by the motion analysis system during barefoot walking. ResultsThe intervention group demonstrated significantly more pain relief and improved function compared to the control group. A significant increase was observed in the gait speed, total support time, and single support time (P < 0.05). Moreover, there was a significant decrease in the step width and initial double support time of the patients after receiving Swedish massage (P < 0.05). ConclusionIt can be concluded that Swedish massage may positively affect pain relief and function improvement in patients with knee OA. Also, Swedish massage was found to improve the spatiotemporal parameters in the patients. This may have important clinical implications regarding the rehabilitation of patients with knee OA.

Quantitative gait analysis of patients with severe sacroiliac joint dysfunction: a prospective clinical study.

Sacroiliac joint (SIJ) dysfunction is a chronic painful condition responsible for up to 30% of back pain. Treatment modalities include physiotherapy, intraarticular analgesic injections, ablation techniques or SIJ fusion. The severity of SIJ dysfunction is commonly assessed via subjective pain or disability scales. Quantitative gait analysis offers an objective means of evaluating patients with SIJ dysfunction prior to its surgical treatment. Ten patients diagnosed with severe SIJ dysfunction were matched with 10 healthy controls. All individuals underwent quantitative 3D gait analysis using the Qualisys program and statistical analysis was performed to identify significant differences in gait parameters between the two groups. Two groups of data were obtained; angular parameters described by the Gait Profile Score (GPS) and spatiotemporal parameters described in standard SI units. Statistically significant differences were found between the patient and control group for parameters: overall GPS (p = 0,049), hip abduction/adduction (p = 0,017) and ankle plantar/dorsal flexion (p = 0,003), stride length (p = 0,002), step length (p = 0,001), swing time (p = 0,03) and initial double limb support (p = 0,02). This paper is the first to perform complex quantitative gait analysis of patients with SIJ dysfunction and to compare it with healthy individuals. These results can provide clinicians with baseline gait values for these patients in order to objectively quantify the extent of their disease.

Gait outcomes following proximal tibial tumor resection and endoprosthetic reconstruction.

Despite the proximal tibia being a common site of primary malignant bone tumors, there is limited information about gait function following proximal tibial tumor resection and endoprosthetic reconstruction (PTR). What is the impact of PTR on gait and quality of life? This was a cross-sectional study of patients ≥18 years old who were ≥2 years post-PTR compared to a control group of similar age and sex distribution. Eighteen participants (9 PTR, 9 Control) were recruited. Gait spatial-temporal data, joint kinematics and kinetics were collected at preferred and fast walking speeds. Community walking cadence, health-related quality of life (SF-36) and knee joint torque were assessed. Comparisons were performed using one-way ANOVAs with Bonferroni corrections for multiple comparisons. Nonparametric tests were used for data not normally distributed. Mean age was 31 years for each group (PTR range = 18-42 yrs, Control range = 18-44 yrs). Compared to both control and nonsurgical limbs, the surgical limb exhibited significantly decreased % single limb support time, reduced heel rise during terminal stance and an absence of normally occurring knee flexion angles, extensor moments and power generation during initial double limb support. Additionally, a reduced peak plantar flexor moment was found for the surgical as compared to the control limb. The number of gait abnormalities increased during fast walking. Significantly reduced surgical knee extensor torque on isokinetic testing and weakness of the knee and ankle on clinical examination support gait findings. During community walking, the number of low frequency strides was an average of 5.3 % greater for the PTR group (p < 0.05). Norm-based PTR group SF-36 component scores were within normal values (53.4 physical, 56.5 mental). Gait abnormalities were consistent with ankle muscle resection and transposition and knee extensor mechanism disruption. Despite these deficits, walking speed and quality of life were relatively normal.

Functional donor-site morbidity after soleus muscle-flap procedure in the treatment of lower limb severe injuries.

The gastrocnemius and soleus muscle flaps are the most commonly used transfer flaps to treat lower limb severe lesions. The use of the muscle as coverage tissuemay incur in functionality loss and motor control deficits. The aim of this study is to assess whether functional deficits are present during gait, posture and heel rise test (HRT). From 2008-2013 we treated 9 patients suffering from complex injury of the lower third of the leg (Gustilo III B). A population of 9 patients (group A) was examined after reconstruction with a soleus muscle flap. The results were compared with a control population (group B: 9 patients). Each patient performed at least 3 gait tests at a fast pace, 2 posture tests and 2 HRT on an inclined plane. Gait parameters for group A: Spatio-temporal parameters such as step length, cadence were reduced compared to the homolateral leg (p < 0.05). The initial double support phase was shorter in relation to the final phase and the first peak in the vertical ground reaction component was reduced compared to the contralateral leg.Posture for the group A: the mediolateral excursion (during open- and closed-eyes test) and the related mean velocity (in the open-eyes test) were significantly lower compared to the control group (p < 0.05).HRT for group A: the number of rises and relative height and angular excursion were reduced in the operated leg in relation to the control group (p < 0.05) and to the contralateral leg. The patients treated with the soleus muscle used as tissue defect coverage completely recovered the ability to walk but showed some deficits in kinetic parameters during the body weight-loading phase. During gait prolonged muscle activity compared to controls was observed. The absence of soleus (group A) revealed no significant alterations in postural control. However, the HRT remained the most relevant test to measure patients' performance when treated with soleus flap in relation to the control group.

Functional Comparison of a Pediatric Patient With Osteosarcoma and Limb-Sparing Distal Femoral Endoprosthesis With an Identical Twin

Background/Objective: In children, limb salvage techniques have been more slowly adopted because of concerns of complications from multiple surgical procedures, the sacrificing of the physis, and the leg-length discrepancy that can ensue. The purpose of this study was to compare gait and function between a pediatric patient with a distal femur replacement and his identical, healthy twin brother. Methods: Design: A single, case-control design was used. Participants: A 13-year-old adolescent boy underwent a distal femoral resection and endoprosthetic reconstruction with a noninvasive extendible endoprosthesis. The control was the healthy, identical twin brother of the case patient. Main Outcome Measure(s): Functional movement testing consisting of 5× Sit-to-Stand Test, 10-m Walk Test, Timed Up and Go (TUG) test, and L-test. Spatiotemporal gait analysis was used to assess degree of asymmetry. Results: Comparisons were mixed across the functional movement testing, with the patient performing inferiorly on the 5× Sit-to-Stand Test and the 10-m Walk Test and superiorly on the TUG test and the L-test. Degree of asymmetry for step time, swing time, single support, and initial double support were all significantly different (P ≤ .05), with the patient being less symmetric in all measures. Limitations: This study is limited by its small sample size and a comparison with a single time point. Conclusion: Although the patient is doing well functionally, asymmetries remain compared with his twin. Future research should focus on more direct comparison of subjects who have undergone different treatment options for sarcoma.

Increased double limb support times during walking in right limb dominant healthy older adults with low bone density

BackgroundOlder adults with low bone mineral density (BMD) may exhibit early markers for physical frailty; however, there is a lack of understanding of the dominant limb support patterns during walking. Research questionThe purpose of this study was to investigate limb support times during walking in healthy older adults with low BMD. MethodsSeventy-seven right limb dominant older adults (48 female subjects, 29 male subjects) participated in the study. Each participant's BMD (g/cm2) was measured by dual-energy x-ray absorptiometry (DEXA), and a motion capture system was utilized to measure temporal-spatial gait parameters (cadence, speed, stride length, and limb support times). The limb support times included initial double limb support (IDS), single limb support (SS), and terminal double limb support (TDS) in the stance phase. ResultsThose limb support times were significantly different (F = 44.28, p = 0.001) and demonstrated an interaction with dominance (F = 9.44, p = 0.003). In stance phase, the IDS was longer on the non-dominant limb (t = −3.07, p = 0.003); however, the TDS was significantly longer on the dominant limb (t = 3.07, p = 0.003). The stride length was longer on the dominant limb (t = 2.45, p = 0.02) and was positively associated with single limb support on the dominant limb (r = 0.34 p = 0.001) compared with the non-dominant limb (r = −0.29, p = 0.001). SignificanceThis longer stride length and single limb loading pattern on the dominant limb could increase asymmetrical balance in the stance phase. The gait modification strategies used to increase stride length on the non-dominant limb may allow for more functional symmetrical gait. Further investigation of asymmetric limb support patterns and gait modification strategies might be needed to enhance functional gait performance.

Gender differences in asymmetrical limb support patterns between subjects with and without recurrent low back pain

New insight regarding limb-dominance effects on temporal-spatial gait parameters is needed to further investigate subjects with recurrent low back pain (LBP). Although an asymmetrical gait pattern was found to reflect natural functional differences, there is a lack of information regarding gender differences on dominant limb support patterns in subjects with LBP. The purpose of this study was to investigate temporal-spatial gait parameters based on limb dominance and gender between subjects with and without LBP. One hundred and ten right limb dominant older adults (51 subjects with LBP and 59 control subjects) participated in the study. A three-dimensional motion capture system was utilized to measure temporal-spatial gait parameters, including initial double, single, and terminal double limb support times and walking speed. The gender differences between subjects with and without LBP were analyzed based on dominance for those parameters. Overall, limb dominance demonstrated significant differences on single and terminal double limb support times as well as walking speed. Limb dominance also demonstrated interactions on group x gender for single limb support time and walking speed. The male subjects with LBP demonstrated significantly increased single limb support times on the non-dominant limb. The significant gender and group interactions based on limb dominance account for a possible pain avoidance, asymmetrical limb support pattern. The causal pathway in dominance dependency gait by unweighted ambulation might be considered as an intervention for correcting these gait deviations in subjects with LBP. The specific modification recovery profiles of the subjects with LBP could shed light on variability of current LBP experiences of the subjects and reasons for gait deviations. Clinicians need to consider the mechanism of dominant limb dependency, which requires postural control strategies in male subjects with recurrent LBP.

Effect of observation on lower limb prosthesis gait biomechanics: Preliminary results.

The Hawthorne effect, a subcategory of reactivity, causes human behavior to change when under observation. Such an effect may apply to gait variation of persons with prosthetics or orthotics devices. This study investigated whether the presence of observers directly affects the gait pattern of users of lower limb prostheses. Within-subject intervention study. Primary outcome measures were gait parameters of initial double support time and upper body lateral tilt angle, which were collected with a mobile sensor attached to the subjects' back. To make subjects feel unwatched, a certain amount of deception was necessary, and two different conditions were created and statistically compared against each other: one in which the subjects were initially unaware of the attention of observers and another one in which the same subjects were aware of a group of observers. Data from two subjects using trans-femoral prosthesis are reported. Findings included a change in step initial double support percentage by up to 14.2% (p = 0.019). Considerable changes were also noted in secondary outcome measures including speed, stride length, and stride symmetry. A reactivity effect of observation exists in prosthetics gait analysis. More comprehensive studies may be motivated by these preliminary findings. Results of this study suggest that users of lower limb prostheses walk differently when their gait is being assessed (e.g. in the prosthetist's office) than in situations without observers. This may in part explain the clinical experience that modifications of prosthetic fit or alignment provide only short-term betterment.

Gait analysis of patients with knee osteoarthritis before and after Chinese massage treatment

The objective of this study was to evaluate the effectiveness of Chinese massage therapy in patients with knee osteoarthritis (OA) by measuring lower-limb gait parameters. We recruited 20 women with knee OA, who then underwent Chinese massage therapy three times per week for 2 weeks. The patients underwent gait evaluation using a six-camera infrared motion analysis system. They completed Western Ontario and McMaster Universities Osteoarthritis Index questionnaires before and after treatment. We calculated the forward speed, step width, step length, total support time percentage, initial double support time percentage, and single support time percentage. We also measured the angles at the knee, hip, and ankle during the stance phase of walking. The results showed statistically significant mean differences in knee pain relief, alleviation of stiffness, and physical function enhancement after therapy (P < 0.05). The patients gained significantly faster gait speed, greater step width, and increased total support time percentage after the Chinese massage therapy (P < 0.05). There were no significant differences in the range of motion or initial contact angles of the knee, hip, or ankle during the stance phase of walking. We concluded that Chinese massage is a beneficial complementary treatment and an alternative therapy choice for patients with knee OA for short-term pain relief. Chinese massage may improve walking ability for these patients.

Excess Body Weight Loss is Associated with Nonpathological Gait Patterns in Women 4 to 5 Years After Bariatric Surgery

This study examined relationships between excess body weight (EBW) loss and current gait and functional status in women 5 years after Roux-en-Y gastric bypass surgery. Gait data were analyzed in nine female bariatric patients for relationships with longitudinal changes in weight, body composition, and physical function assessed by the Short Musculoskeletal Functional Assessment (SMFA) questionnaire and the timed "get-up-and-go" (TGUG) test. Gait characteristics in the bariatric sample were also compared to an age- and BMI-matched nonsurgical reference sample from the Fels Longitudinal Study. Bariatric patients lost an average of 36.4 kg (61.1%) of EBW between preoperative and 5-year follow-up visits (P < 0.01); SMFA function index scores and TGUG times also decreased (both P < 0.01). Degree of EBW loss was correlated with less time spent in initial double support and more time in single support (both P = 0.02), and for all gait variables, the bariatric sample fell within the 95% confidence intervals of gait/EBW relationships in the reference sample. Gait and function 5 years after bariatric surgery were characteristic of current weight, not preoperative obesity, suggesting that substantial, sustained recovery of physical function is possible with rapid surgical weight loss.

Age-related changes in spatiotemporal characteristics of gait accompany ongoing lower limb linear growth in late childhood and early adolescence

Walking gait is generally held to reach maturity, including walking at adult-like velocities, by 7–8 years of age. Lower limb length, however, is a major determinant of gait, and continues to increase until 13–15 years of age. This study used a sample from the Fels Longitudinal Study (ages 8–30 years) to test the hypothesis that walking with adult-like velocity on immature lower limbs results in the retention of immature gait characteristics during late childhood and early adolescence. There was no relationship between walking velocity and age in this sample, whereas the lower limb continued to grow, reaching maturity at 13.2 years in females and 15.6 years in males. Piecewise linear mixed models regression analysis revealed significant age-related trends in normalized cadence, initial double support time, single support time, base of support, and normalized step length in both sexes. Each trend reached its own, variable-specific age at maturity, after which the gait variables’ relationships with age reached plateaus and did not differ significantly from zero. Offsets in ages at maturity occurred among the gait variables, and between the gait variables and lower limb length. The sexes also differed in their patterns of maturation. Generally, however, immature walkers of both sexes took more frequent and relatively longer steps than did mature walkers. These results support the hypothesis that maturational changes in gait accompany ongoing lower limb growth, with implications for diagnosing, preventing, and treating movement-related disorders and injuries during late childhood and early adolescence.

Multiple Sclerosis Alters the Mechanical Work Performed on the Body’s Center of Mass During Gait

Patients with multiple sclerosis (MS) have less-coordinated movements of the center of mass resulting in greater mechanical work. The purpose of this study was to quantify the work performed on the body's center of mass by patients with MS. It was hypothesized that patients with MS would perform greater negative work during initial double support and less positive work in terminal double support. Results revealed that patients with MS perform less negative work in single support and early terminal double support and less positive work in the terminal double support period. However, summed over the entire stance phase, patients with MS and healthy controls performed similar amounts of positive and negative work on the body's center of mass. The altered work throughout different periods in the stance phase may be indicative of a failure to capitalize on passive elastic energy mechanisms and increased reliance upon more active work generation to sustain gait.

An unstable shoe with a rocker bottom redistributes external work

The purpose of this study was to examine the external work performed by individuals wearing a rocker bottom shoe compared to a standard shoe. It was hypothesized that individuals wearing a rocker bottom shoe would have changes in the amount of work over the course of contact with the ground. External work on the body's centre of mass (BCOM) was calculated for individuals in both conditions. Comparisons for external work were done for positive and negative work for the entire stance phase as well as the initial double support, single support and terminal double support periods. The results revealed that while wearing the rocker bottom shoes, individuals performed an increased amount of negative work and decreased positive work in the initial double support followed by increased positive work in single support compared to a standard sole shoe. Individuals also performed a decreased amount of positive and negative work in terminal double support when wearing the rocker bottom shoes. There were no differences, however, when the stance phase was considered undivided to subphases for either positive or negative work. The results indicate that use of rocker bottom shoes redistributes external work to earlier in the gait cycle, which may not be as energetically efficient. This shift will probably result in increased metabolic energy expenditure as it will require more energy output from proximal hip musculature, which is not as mechanically efficient as the ankle joint in late stance. This could be desirable for individuals who are wearing the shoes for increased caloric burn such as an exercise setting. Furthermore, the increased external work in single support may be causing additional work from the hip extensor musculature (i.e. gluteus maximus). This could possibly be desirable for strengthening and conditioning of the hip extensors.

Personalized rehabilitation of children with cerebral palsy using three-dimensional gait analysis

Objective To study the effectiveness of personalized rehabilitation treatments based on threedimensional gait analysis (3DGA) for improving the walking function of children with cerebral palsy (CP).Methods A total of 21 spastic CP children with diplegia or hemiplegia,IQ scores ＞60,and an average age of 8.5 years received 3DGA.They then received personalized rehabilitation treatment designed according to the 3DGA results.After four weeks of treatment the children accepted 3DGA again.Their gait descriptors before and after treatment were compared. Results After the personalized rehabilitation the subjects'clinical foot dorsiflexion angle,clinical popliteal fossa angle,walking velocity,stride length,step length,peak ankle dorsiflexion in prime stance,peaking ankle plantar flexion in last stance,peak back ground reaction forces (GRFs) and peak vertical GRF in stance all had improved significantly.The cadence,total support time,swing phase,initial double support time,peak knee extension in stance and the peak forward GRF were not,however,significantly different compared with before the personalized rehabilitation treatment. Conclusion Under the guidance of 3DGA,the walking function of spastic CP children improved significantly after 4 weeks of personalized rehabilitation treatment.3DGA can play an important role in formulating personalized rehabilitation protocols and guiding rehabilitation treatment for CP children. Key words: Three-dimensional gait analysis; Cerebral palsy; Rehabilitation

Coactivation of ankle muscles during stance phase of gait in patients with lower limb hypertonia after acquired brain injury

ObjectiveExamine (1) coactivation between tibialis anterior (TA) and medial gastrocnemius (MG) muscles during stance phase of gait in patients with moderate-to-severe resting hypertonia after stroke or traumatic brain injury (TBI) and (2) the relationship between coactivation and stretch velocity-dependent increase in MG activity. MethodsGait and surface EMG were recorded from patients with stroke or TBI (11 each) and corresponding healthy controls (n=11) to determine the magnitude and duration of TA–MG coactivation. The frequency and gain of positive (>0) and significant positive (p<0.05) EMG–lengthening velocity (EMG–LV) slope in MG were related to coactivation parameters. ResultsThe magnitude of coactivation was increased on the more-affected (MA) side, whereas the duration was prolonged on the less-affected (LA) side of both stroke and TBI patients. The difference reached significance during the initial and late double support. The magnitude of coactivation positively correlated with the gain of significant positive EMG–LV slope in TBI patients. ConclusionsIncreased coactivation between TA and MG during initial and late double support is a unique feature of gait in stroke and TBI patients with muscle hypertonia. SignificanceIncreased coactivation may represent an adaptation to compensate for impaired stability during step transition after stroke and TBI.