[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-study-detail:100658935":3},{"organization":4,"outcomesModule":7,"designInfo":24,"detailedDescription":27,"studyPopulation":28,"armGroups":29,"interventions":23,"overallOfficials":36,"centralContacts":40,"locations":49,"responsibleParty":65,"collaborators":23,"id":69,"slug":70,"hasResults":71,"nctId":72,"briefTitle":73,"officialTitle":74,"acronym":75,"eligibilityCriteria":76,"healthyVolunteers":77,"sex":78,"minAge":79,"maxAge":23,"enrollmentInfo":80,"targetDuration":23,"studyType":83,"phases":23,"briefSummary":84,"conditions":85,"keywords":88,"overallStatus":51,"whyStopped":23,"lastUpdateSubmitDate":93,"lastUpdatePostDateStruct":94,"startDateStruct":97,"completionDateStruct":99,"leadSponsor":101,"locationsCount":102},{"fullName":5,"class":6},"Centre National de Rééducation Fonctionnelle et de Réadaptation","OTHER",{"primaryOutcomes":8,"secondaryOutcomes":13,"otherOutcomes":23},[9],{"measure":10,"description":11,"timeFrame":12},"On-Off Quadriceps Electromyographic Activity During the Gait Cycle","Difference in Fine-Wire Electromyographic Activity of the Four Quadriceps Heads Between Participants With Post-Stroke Stiff-Knee Gait and Healthy Controls.\n\nFine-wire electromyographic activity will be recorded with a telemetric electromyograph equipment from the rectus femoris, vastus intermedius, vastus medialis, and vastus lateralis during walking.\n\nFor each muscle, the EMG envelope will be calculated from the raw EMG signal using root mean square processing and expressed over the time-normalized gait cycle.\n\nThe primary analysis will compare quadriceps activation patterns (On-Off) between participants with post-stroke stiff-knee gait and healthy controls assessed at a slow walking speed, with particular attention to the pre-swing and early-swing phases of gait. On-Off activation patterns will be expressed as period(s) during the gait cycle (%).\n\nThe four quadriceps heads will be evaluated individually to identify muscle-specific differences in activation between groups.","Baseline",[14,17,20],{"measure":15,"description":16,"timeFrame":12},"Peak Knee Flexion During the Swing Phase of Gait","Difference in Peak Knee Flexion During the Swing Phase Between Participants With Post-Stroke Stiff-Knee Gait and Healthy Controls.\n\nPeak knee-flexion angle (expressed in degrees) during the swing phase will be measured using a 10-cameras optoelectronic system and compared between participants with post-stroke stiff-knee gait and healthy controls.",{"measure":18,"description":19,"timeFrame":12},"Knee Kinematic Profile During the Gait Cycle","Difference in Sagittal-Plane Knee Kinematics Between Participants With Post-Stroke Stiff-Knee Gait and Healthy Controls.\n\nThe knee flexion-extension angle (expressed in degrees) will be evaluated throughout the time-normalized gait cycle using a 10-cameras optoelectronic system and compared between the two groups.",{"measure":21,"description":22,"timeFrame":12},"Lower-Limb Kinematics","Differences in Hip, Knee, and Ankle Kinematics Between Participants With Post-Stroke Stiff-Knee Gait and Healthy Controls.\n\nThree-dimensional kinematic angle measurements (expressed in degrees) of the hips, knees, and ankles collected with a 10-cameras optoelectronic system will be evaluated to characterize differences in gait patterns between the two groups.",null,{"allocation":23,"interventionModel":23,"interventionModelDescription":23,"primaryPurpose":23,"observationalModel":25,"timePerspective":26,"maskingInfo":23},"CASE_CONTROL","CROSS_SECTIONAL","Stiff-knee gait (SKG) is a common gait impairment following stroke. It is characterized by insufficient knee flexion during the swing phase of walking and may interfere with foot clearance, increase the risk of falls, and lead to compensatory gait strategies associated with increased energy expenditure.\n\nSeveral mechanisms have been proposed to explain SKG after stroke. These include weakness of the hip flexor muscles, reduced propulsion resulting from weakness of the ankle plantar flexors, and inappropriate or spastic activation of the quadriceps during pre-swing and early swing. Inappropriate quadriceps activity may oppose the passive knee flexion that normally develops during these phases of the gait cycle.\n\nDetermining whether individual quadriceps muscles demonstrate abnormal activation is difficult because quadriceps activity during normal walking varies both within and between individuals and is influenced by walking speed. This is particularly relevant when comparing healthy individuals with patients after stroke because patients with hemiparesis generally walk at slower speeds.\n\nExisting normative electromyographic data for the quadriceps have several limitations. Published studies have generally investigated only some of the four quadriceps heads, and the deep vastus intermedius has been insufficiently characterized during walking. Furthermore, available reference data have not consistently been obtained at walking speeds comparable with those observed in people with post-stroke hemiparesis.\n\nThe primary objective of this study is to compare the electromyographic activity of the four quadriceps heads between participants with chronic post-stroke hemiparesis and stiff-knee gait and healthy adult controls.\n\nA secondary objective is to compare gait kinematics between the two groups, particularly knee flexion during the swing phase, in order to investigate the relationship between altered quadriceps activation and the characteristic kinematic pattern of stiff-knee gait.\n\nThe study will include 24 healthy adult controls and 30 adults with chronic post-stroke hemiparesis with stiff-knee gait.\n\nHealthy controls will undergo quantitative gait analysis at the RehaLAB of the Rehazenter. Ultrasound-guided fine-wire electrodes will be inserted into each of the four quadriceps heads: rectus femoris, vastus intermedius, vastus medialis, and vastus lateralis.\n\nHealthy participants will be assessed while walking at a slow speed. This condition is selected because it is intended to provide a healthy reference dataset at a walking speed comparable with that typically observed in participants with post-stroke hemiparesis.\n\nParticipants in the stiff-knee gait group will undergo quantitative gait analysis using the same fine-wire EMG methodology for the four quadriceps heads. Three-dimensional lower-limb kinematics and surface EMG of selected additional lower-limb muscles will also be collected.\n\nFine-wire EMG is used rather than surface EMG for the quadriceps because selective assessment of individual quadriceps heads is required. Surface recordings may contain activity originating from adjacent muscles as a result of cross-talk, and the activity of the deep vastus intermedius cannot be adequately isolated using surface electrodes.\n\nThe primary analysis will compare fine-wire quadriceps EMG activation patterns between participants with stiff-knee gait and healthy controls assessed under the slow-speed reference condition. EMG signals will be evaluated over the time-normalized gait cycle. EMG envelopes will be estimated using the root mean square of the raw EMG signal. Particular attention will be paid to activation during pre-swing and early swing, during which inappropriate quadriceps activity may oppose normal knee flexion.\n\nEach quadriceps head will be evaluated individually, including the rectus femoris, vastus intermedius, vastus medialis, and vastus lateralis.\n\nSecondary analyses will compare gait kinematics between the two groups, with particular attention to sagittal-plane knee motion and peak knee flexion during the swing phase.\n\nThe primary statistical analysis will compare the time-normalized fine-wire EMG trajectories of each quadriceps head between participants with post-stroke stiff-knee gait and healthy controls assessed at the slow-speed reference condition.\n\nThe specific statistical method for this between-group comparison will be Statistical Parametric Mapping. Correction for multiple comparisons will be applied to the significance threshold.\n\nThe overall objective of the study is to establish detailed reference profiles of quadriceps activation during normal walking and determine how these profiles differ from those observed in people with post-stroke SKG. The study may help identify which quadriceps heads most frequently demonstrate atypical activation in SKG and improve understanding of the relationship between abnormal quadriceps activity and reduced knee flexion during the swing phase of gait.","The study population consists of adults with chronic post-stroke hemiparesis and stiff-knee gait receiving care at the Rehazenter and healthy adult volunteers.\n\nPatients with SKG are selected from individuals attending the Rehazenter who meet the study eligibility criteria. Healthy controls are recruited on a voluntary basis, including through invitations to Rehazenter personnel and family members of patients attending consultations.",[30,33],{"label":31,"type":23,"description":32,"interventionNames":23},"Post-Stroke Stiff-Knee Gait","Adults with chronic right- or left-sided hemiparesis following stroke who are able to walk independently and demonstrate reduced knee flexion during the swing phase of gait. Participants undergo quantitative gait analysis with ultrasound-guided fine-wire EMG of all four quadriceps heads and three-dimensional gait analysis.",{"label":34,"type":23,"description":35,"interventionNames":23},"Healthy Controls","Adults without a condition expected to affect gait and without abnormal knee kinematics on clinical observation.\n\nParticipants undergo quantitative gait analysis with ultrasound-guided fine-wire EMG of the rectus femoris, vastus intermedius, vastus medialis, and vastus lateralis while walking at a slow speed selected to provide a reference condition comparable with the walking speed of participants with post-stroke stiff-knee gait. Three-dimensional gait kinematics is recorded simultaneously.",[37],{"name":38,"affiliation":5,"role":39},"Frédéric Dierick, PhD","STUDY_DIRECTOR",[41,46],{"name":42,"role":43,"phone":44,"phoneExt":23,"email":45},"Frédéric Chantraine, MD","CONTACT","+35226981","frederic.chantraine@rehazenter.lu",{"name":47,"role":43,"phone":23,"phoneExt":23,"email":48},"Céline Schreiber, MSc","celine.schreiber@rehazenter.lu",[50],{"facility":5,"status":51,"city":52,"state":52,"zip":53,"country":52,"countryCode":54,"cosmosGeoPoint":55,"geoPoint":60,"contacts":61},"RECRUITING","Luxembourg","2674","LU",{"type":56,"coordinates":57},"Point",[58,59],6.13268,49.60982,{"lat":59,"lon":58},[62,64],{"name":42,"role":43,"phone":63,"phoneExt":23,"email":45},"+352269894008",{"name":47,"role":43,"phone":23,"phoneExt":23,"email":23},{"type":66,"investigatorFullName":67,"investigatorTitle":68,"investigatorAffiliation":5,"oldNameTitle":23,"oldOrganization":23},"SPONSOR_INVESTIGATOR","Frédéric Chantraine","Medical Doctor","100658935","quadriceps-muscle-activity-and-gait-kinematics-in-patients-with-post-stroke-stiff-knee-gait-compared-with-healthy-controls-100658935",false,"NCT07857967","Quadriceps Muscle Activity and Gait Kinematics in Patients With Post-Stroke Stiff-Knee Gait Compared With Healthy Controls","Comparison of Quadriceps Electromyographic Activity and Gait Kinematics Between Patients With Post-Stroke Stiff-Knee Gait and Healthy Controls","FW QUADRI","Inclusion Criteria (Post-Stroke SKG Group):\n\n* Clinical diagnosis of cerebral stroke with hemiparesis.\n* Age greater than 18 years.\n* Right- or left-sided hemiparesis following stroke.\n* Stroke occurred at least 6 months before assessment.\n* Able to walk independently without a technical walking aid.\n* Reduced knee flexion during the swing phase of gait (stiff-knee gait) identified by visual observation by an experienced clinician.\n\nExclusion Criteria (Post-Stroke SKG Group):\n\n* Other disease or history of disease likely to influence gait, including peripheral neurological, cerebellar, vestibular, rheumatological, orthopedic, or metabolic disorders.\n* Visual or hearing impairment.\n* Medication likely to affect gait.\n* Botulinum toxin injection into the lower-limb muscles within the preceding 6 months\n* Use of illicit substances within 24 hours before the gait assessment.\n\nInclusion Criteria (Healthy-Control Group):\n\n* Age greater than 18 years.\n* No pathology likely to alter gait.\n* No abnormality of knee kinematics identified during visual observation by an experienced clinician.",true,"ALL","18 Years",{"count":81,"type":82},50,"ESTIMATED","OBSERVATIONAL","Stiff-knee gait (SKG) is a frequent gait abnormality in people with post-stroke hemiparesis and is characterized by insufficient knee flexion during the swing phase of walking. One potential mechanism is inappropriate activation of one or more heads of the quadriceps during pre-swing and early swing.\n\nThis observational study will compare quadriceps electromyographic activity and gait kinematics between adults with chronic post-stroke hemiparesis with SKG and healthy adult controls.\n\nThe study will include 30 participants with post-stroke SKG and 24 healthy controls. Quantitative gait analysis will be performed using three-dimensional motion analysis together with electromyography (EMG). Ultrasound-guided fine-wire electrodes will record the activity of all four heads of the quadriceps: rectus femoris, vastus intermedius, vastus medialis, and vastus lateralis.\n\nHealthy controls will be assessed while walking at a slow speed selected to provide a reference condition that is comparable with the walking speeds typically observed in participants with post-stroke hemiparesis.\n\nThe primary outcome is the difference in fine-wire EMG activation patterns of the four quadriceps heads between participants with post-stroke SKG and healthy controls, with particular attention to pre-swing and early swing.\n\nSecondary outcomes will assess differences in gait kinematics between groups, including peak knee flexion during the swing phase and knee flexion-extension patterns throughout the gait cycle.\n\nThe study aims to improve understanding of the muscular mechanisms underlying post-stroke SKG and to establish relevant fine-wire EMG reference patterns for all four quadriceps heads in healthy individuals walking at a speed comparable with patients with hemiparesis.",[86,87],"Stroke","Hemiparesis",[89,90,91,92],"Stiff-knee gait","Quadriceps","Electromyography","Gait analysis","2026-09-29",{"date":95,"type":96},"2026-10-05","ACTUAL",{"date":98,"type":96},"2025-04-15",{"date":100,"type":82},"2026-12-31",{"name":67,"class":6},1]