Search

Background: There is a paucity of data on mid to long-term gait outcomes after total knee arthroplasty. The aims of this longitudinal study were: to assess the evolution of both clinical and gait outcomes before and up to seven years after primary total knee arthroplasty (TKA) in a cohort of patients with knee osteoarthritis.Methods: This study included 28 patients evaluated before and up to seven years after primary TKA with both gait analysis and patient reported outcomes; of these, 20 patients were evaluated one year after surgery as well. Kinematic outcomes during gait (gait velocity, dimensionless gait veolicity, maximal knee flexion and knee range of motion), pain relief, Western Ontario and MacMaster Osteoarthritis Index (WOMAC), quality of life and patient satisfaction were assessed and compared at each visit with the paired Wilcoxon signed rank test (p < 0.05).Results: The significant improvement achieved at one year after TKA was stable up to seven years after surgery, with all clinical and kinematic outcomes unchanged, except for gait velocity, with a significant decrease over time (1.3 (1.1-1.4) m/s one year after TKA versus 1.0 (0.9-1.1) m/s, p < 0.05 up to seven years after).Conclusion: Patients with knee osteoarthritis significantly improve their clinical and kinematic outcomes at one year postoperatively and maintain the gain up to seven years after primary TKA, except for gait velocity which decreases over time, most likely along with ageing.

Background Excessive Knee Flexion Gait Pattern (KFGP) is a common gait deviation in many pathological conditions. The contractures of the muscles that have been identified as being responsible of KFGP are: iliopsoas, hamstring and gastrocnemius. Research question How do isolated contractures of the iliopsoas, hamstrings and gastrocnemius impact knee flexion during gait? Methods Three levels of contracture (mild, moderate and severe) were simulated bilaterally using an exoskeleton on 10 healthy participants for iliopsoas, hamstring and gastrocnemius muscles. A gait analysis session was performed to evaluate the joint kinematics according to the different simulated contractures. Thirty one parameters were chosen to analyze the kinematics of the thorax, pelvis, hip, knee and ankle. A principal component analysis (PCA) was used to determine the kinematic parameters influenced by contractures. Results In addition to a permanent knee flexion observed for the three muscles with contracture: the contracture of the iliopsoas induces a large hip flexion with pronounced anterior pelvis tilt; the contracture of the hamstrings induces an ankle dorsiflexion during the support phase with a posterior pelvis tilt; the contracture of the gastrocnemius induces an absence of first and second rocker of the ankle with a slight flexion of hip and a slight anterior pelvis tilt. Significance These results support the identification of the muscles responsible for a KFGP. A better knowledge of the interactions between contractures and associated joint kinematics of the same and adjacent joints will support the interpretation of gait analyses by more precisely and faster targeting the concerned muscle.

Contracture is a permanent shortening of the muscle-tendon-ligament complex that limits joint mobility. Contracture is involved in many diseases (cerebral palsy, stroke, etc.) and can impair walking and other activities of daily living. The purpose of this study was to quantify the reliability of an exoskeleton designed to emulate lower limb muscle contractures unilaterally and bilaterally during walking. An exoskeleton was built according to the following design criteria: adjustable to different morphologies; respect of the principal lines of muscular actions; placement of reflective markers on anatomical landmarks; and the ability to replicate the contractures of eight muscles of the lower limb unilaterally and bilaterally (psoas, rectus femoris, hamstring, hip adductors, gastrocnemius, soleus, tibialis posterior, and peroneus). Sixteen combinations of contractures were emulated on the unilateral and bilateral muscles of nine healthy participants. Two sessions of gait analysis were performed at weekly intervals to assess the reliability of the emulated contractures. Discrete variables were extracted from the kinematics to analyse the reliability. The exoskeleton did not affect normal walking when contractures were not emulated. Kinematic reliability varied from poor to excellent depending on the targeted muscle. Reliability was good for the bilateral and unilateral gastrocnemius, soleus, and tibialis posterior as well as the bilateral hamstring and unilateral hip adductors. The exoskeleton can be used to replicate contracture on healthy participants. The exoskeleton will allow us to differentiate primary and compensatory effects of muscle contractures on gait kinematics.

Background Contractures of a major joint in the lower limbs may impair human walking in addition to other daily living activities. A contracture is defined as the inability of a joint to perform the full range of motion and excessive resistance during passive mobilization of the joint. Few studies have reported methods describing how to evaluate contractures. Understanding the association among all of these studies seems essential to improve patient management. Therefore, we conducted a systematic review on this topic to elucidate the influence of contractures on gait kinematics. Methods An electronic search in the literature will be conducted. Studies were screened by title and abstract and full texts were evaluated secondarily for definitive inclusion. The quality of the included studies was assessed independently by the two review authors with the Modified Quality Assessment Checklist. The included studies were separated into three categories: pathological contracture versus healthy controls (descriptive), simulated contracture versus healthy controls (experimental), and pre- and post-kinematics after surgical muscle lengthening (surgery). Findings From a total of 4402 references, 112 original articles were selected, and 28 studies were identified in this systematic review. No significant difference between raters was observed on the total score of the Modified Quality Assessment Checklist. Interpretation Contractures influence walking depending on the location (muscle) and the contracture level (muscle–tendon length). After giving a definition of contracture, this review identified some contracture alterations, such as plantarflexion, knee flexion and hip flexion contractures, with a kinematic description and presented possible different compensations.

Soft-tissue contracture is usually defined as a permanent shortening of the musculotendinous complex limiting the mobility of a joint. Contracture is mainly due to the consequences of joint immobilization and is one of the main causes of gait disorders. Different approaches have been used to evaluate the influence of contractures on gait, such as observational, experimental, simulation, and animal studies. The main effects of contracture can be summarized muscle by muscle: soleus contracture causes an ankle plantarflexion; gastrocnemius contracture causes a knee flexion and an ankle plantarflexion; hamstring contracture causes a knee flexion and an increased posterior pelvic tilt; psoas contracture causes a hip flexion and a specific knee flexion pattern. Identifying and understanding specific gait patterns associated with contractures support clinical gait analysis and therefore the management of patients with gait deviations. However, contractures are rarely isolated and are often combined with other clinical impairments, such as spasticity and weakness, making their interpretation complex. New approaches, such as advanced neuromusculoskeletal simulations and machine learning, are needed to improve knowledge on the relationships between impairments (including contractures) and gait deviations

Introduction Ankle plantarflexion contracture results from a permanent shortening of the muscle-tendon complex. It often leads to gait alterations. The objective of this study was to compare the kinematic adaptations of different degrees of contractures and between isolated bilateral gastrocnemius and soleus emulated contractures using an exoskeleton. Methods Eight combinations of contractures were emulated bilaterally on 10 asymptomatic participants using an exoskeleton that was able to emulate different degrees of contracture of gastrocnemius (biarticular muscle) and soleus (monoarticular muscle), corresponding at 0°, 10°, 20°, and 30° ankle plantarflexion contracture (knee-flexed and knee-extended). Range of motion was limited by ropes attached for soleus on heel and below the knee and for gastrocnemius on heel and above the knee. A gait analysis session was performed to evaluate the effect of these different emulated contractures on the Gait Profile Score, walking speed and gait kinematics. Results Gastrocnemius and soleus contractures influence gait kinematics, with an increase of the Gait Profile Score. Significant differences were found in the kinematics of the ankles, knees and hips. Contractures of soleus cause a more important decrease in the range of motion at the ankle than the same degree of gastrocnemius contractures. Gastrocnemius contractures cause greater knee flexion (during the stance phase) and hip flexion (during all the gait cycle) than the same level of soleus contractures. Conclusion These results can support the interpretation of the Clinical Gait Analysis data by providing a better understanding of the effect of isolate contracture of soleus and gastrocnemius on gait kinematics.

L'improvisateur est un Etranger Absolu de la musique. Il peut parler toutes les langues et les hors-champs de la langue, bruits, cris, chuchotements, s'identifier aux bruissements du monde, se découvrir un devenir minéral, végétal, animal. Mais de langue propre, sauf par parti-pris idéologique, il n'en a aucune. Ou plutôt, c'est dans la mesure où il n'en a aucune qu'il m'intéresse, qu'il est moi, c'est à dire un autre...

Introduction : La retraction limite la mobilite des articulations. L’objectif de cette etude est de concevoir et d’evaluer la reproductibilite d’un exosquelette capable d’emuler des retractions. Methode : Quatre combinaisons de retraction ont ete emulees sur neuf participants « sains » : unilaterales et bilaterales sur les muscles gastrocnemiens et soleaires. Deux sessions d’analyse de la marche ont ete effectuees a une semaine d’intervalle afin d’evaluer la reproductibilite de l’emulation des retractions. Resultats : L’exosquelette a ete construit avec succes selon les regles fixees. Une reproductibilite d’acceptable a excellente de ce nouvel outil a ete mesuree pour l’emulation de retractions sur les muscles gastrocnemiens et soleaires. Conclusion : Cette nouvelle approche permettra de mieux comprendre les alterations de marche en lien avec les retractions en differenciant alterations et compensations.

Background Lower limb deficits have been widely studied during gait in cerebral palsy, deficits in upper body have received little attention. The purpose of this research was to describe the characteristics of trunk movement of cerebral palsy children in terms of type of deficits (diplegia/hemiplegia) and gross motor function classification system (1, 2 or 3). Methods Data from 92 cerebral palsy children, which corresponds to 141 clinical gait analysis, were retrospectively selected. Kinematic parameters of trunk were extracted from thorax and spine angles in the sagittal, transverse and coronal planes. The range of motion and the mean positions over the gait cycle were analysed. Intra-group differences between the children with diplegia or hemiplegia, gross motor function classification systems 1 to 3 and typically developing participants were analysed with Kruskal–Wallis tests and post hoc tests. Pearson correlation coefficients between the gait profile score normalised walking speed and kinematic parameters of the thorax were assessed. Findings The results revealed: 1) the range of motion of the thorax and spine exhibited more significant differences between groups than the mean positions; 2) greater levels of impairment were associated with higher thorax range of motion, and 3) the children with diplegia and gross motor function classification system 3 exhibited a greater range of motion for all planes with the exception of spine rotation. Interpretation This study confirmed that greater levels of impairment in cerebral palsy are associated with greater thorax range of motion during gait. The thorax plays an important role during gait in cerebral palsy.

Introduction La marche en flexion excessive de genoux est un defaut frequent chez les patients atteints de paralysie cerebrale. Les retractions des muscles ayant ete identifiees comme pouvant etre responsables d’une marche de type « genoux flechis » sont les : ilio-psoas, ischio-jambiers et gastrocnemius. Ainsi notre objectif etait de comparer les effets des retractions de differents muscles pouvant causer une marche « genoux flechis » sur la cinematique. Materiel et methodes Des retractions (faibles, moyennes et fortes) ont ete emulees bilateralement a l’aide d’un exosquelette sur 10 participants « sains » pour les muscles ilio-psoas, ischio-jambiers et gastrocnemius. Une session d’analyse de la marche a ete effectuee afin d’evaluer la cinematique articulaire selon les differentes retractions emulees. Trente et une variables ont ete choisies pour analyser la cinematique du thorax, bassin, hanche, genou et cheville. Une analyse en composante principale (ACP) a ete utilisee pour determiner les variables cinematiques influencees par la contracture. L’effet sur la cinematique (base sur les variables selectionnees via l’ACP) des trois muscles retractes a ete compare (test de Kruskal-Wallis). Resultats En plus d’une flexion permanente de genou observee pour les 3 muscles retractes, la retraction des ilio-psoas induit un important flexum de hanche avec une anteversion du bassin prononcee ; la retraction des ischio-jambiers induit une dorsiflexion de cheville durant la phase d’appui avec une retroversion du bassin ; la retraction des gastrocnemius induit une absence de premier et deuxieme pivot de la cheville avec un leger flexum de hanche et une legere anteversion du bassin. Discussion – conclusion Sur la base de ces resultats, il est possible d’identifier les muscles responsables d’un pattern de marche « genoux flechis ». Une meilleure connaissance de ce type de cinematique permet d’ameliorer l’interpretation des analyses de marche en ciblant le muscle altere de maniere plus precise et plus rapide.

s / Gait & Posture 39S (2014) S1–S141 S27 muscles of each lower limb. All these data allowed us to compute the GDI [1], the Gillette Gait Index (GGI) [2] and our EMG index. Moreover,we recorded twovideos (face andprofile) of eachpatient to compute his/her Edinburgh Visual Gait Score (EVGS) [4]. To evaluate our EMG index, we then compute its correlation with each of these three kinematics-based indices. Results: EMGprofiles of healthy subjects are presented on Fig. 1 (left) for each of the seven muscles selected. They are actually consistent with previous recording reported in literature [4]. Mean index value for patients is 63.0 (±10.4, SD) and the range was between 47.8 and 91.6. The EMG profile of one patient with quit low score (57.1 in average) is presented on Fig. 1 (right). Computed by sides, the correlations with our index goes from fair for GDI (R2 =0.42) to good for GGI and EVGS (respectively R2 =0.62 and R2 =0.69). This result remains similar when computed by subjects (mean of two sides) with slightly higher R2 values of 0.49 for GDI, 0.72 for GGI and 0.71 for EVGS. Discussionandconclusions:Ourmain result is that our index is consistent with kinematics indices as correlations are fair to good. It thus can be used to evaluate gait and is complementary to one of these three kinematical indices providing synthetic vision on patients’ motor control abilities. In conclusion, as EVGS and our index use ordinary and simple clinical devices, the physician can compute both of them to get relevant information both for kinematics and neuromotor aspects in clinical routine.

Preserving or restoring the ability to walk without pain, fatigue or any gait alterations is considered a priority for activities of daily living and is closely related to quality of life. Numerous alterations of the neuro-musculo-skeletal system lead to gait deviations. To treat these alterations, a precise understanding of gait deviations is required. For patients with gait disorders, instrumented gait analysis can be performed to measure precisely the gait deviations. Among the varied causes of gait alterations, one of the most frequent is contractures that affect numerous pathologies. It corresponds to a permanent shortening of a musculo-tendinous complex limiting the mobility of the joints. It is involved in many pathologies (cerebral palsy, stroke, clubfoot, burns, etc.) The global objective of this thesis was to study the effects of contractures on human walking. For this purpose, a device for emulating contractures has been built and evaluated. This device consists of an exoskeleton and ropes to limit joint range of motion of the major lower limb muscles affected by contractures. With this device, the effect of contractures of the musculo-tendinous complex was analysed. Isolated contractures were emulated on 36 participants unilaterally and bilaterally and an instrumented gait analysis was performed. The kinematic patterns obtained for each joint were then used to link kinematic gait alterations with muscle contractures. It has been shown that contracture of gastrocnemius can cause a knee flexion pattern, while a contracture of the soleus shows moderate changes in knee kinematics. Moreover, the relationship between the level of contracture of gastrocnemius / soleus and the progression of the equinus gait (increase in plantar flexion during walking) is not linear. «Knee flexion» gait pattern may be caused by the contractures of the iliopsoas, hamstrings and gastrocnemius. Particular kinematic patterns have been identified in relation to the muscles responsible to the «knee flexion» gait pattern. It has also been shown that retractions of the muscles of the lower limb have important specific effects on the mean position of the trunk and pelvis in the sagittal plane. Behind the scientific objective, the results of this project have the potential to improve the choice of treatment strategies and therefore to have an impact on patient’s quality of life, Etre capable de marcher sans ressentir de douleur, fatigue ou autres altérations est considéré comme une priorité pour les activités quotidiennes et est étroitement lié à la qualité de vie de chacun. De nombreuses atteintes du système neuro-musculo-squelettique peuvent engendrer des altérations de la marche. Une compréhension précise de ces altérations est nécessaire pour optimiser les stratégies thérapeutiques. Parmi ces atteintes, la rétraction musculaire est l'une des plus fréquentes. Elle correspond à un raccourcissement permanent du complexe musculotendineux limitant ainsi la mobilité des articulations. Elle est impliquée dans de nombreuses pathologies (paralysie cérébrale, hémiplégie, pieds bots, brûlures, etc.) L'objectif global de ce travail de thèse était d'étudier les effets des rétractions sur la marche humaine. Pour cela, un dispositif permettant d'émuler des rétractions a été mis en place et évalué. Ce dispositif est composé d'un exosquelette et de cordes permettant de limiter les amplitudes articulaires, simulant ainsi la rétraction des principaux muscles des membres inférieurs atteints par cette pathologie. Grâce à ce dispositif, l'effet des rétractions des muscles a été analysé. Des rétractions isolées ont été émulées sur 35 participants unilatéralement et bilatéralement et une analyse quantifiée de la marche a été réalisée. Les patterns cinématiques obtenus sur chaque articulation ont été ensuite utilisés pour analyser les liens entre altérations de marche et rétractions musculaires. Il a été montré que la rétraction des gastrocnemius peut provoquer un pattern de marche genoux fléchis, alors qu'une rétraction du soleus montre peu de modifications de la cinématique du genou. De plus, le lien entre la sévérité de la rétraction des gastrocnemius / soleus et la progression de la marche digitigrade (augmentation de la flexion plantaire pendant la marche) n'est pas linéaire. La marche «genoux fléchis» peut être causée par les rétractions des ilio-psoas, ischio-jambiers et gastrocnemius. Des patterns cinématiques particuliers ont été identifiées en lien avec les muscles responsables de la marche «genoux fléchis». Il a été également montré que les rétractions des muscles du membre inférieur ont des effets importants spécifiques sur la position moyenne du tronc et du bassin dans le plan sagittal. Derrière son objectif scientifique, les résultats obtenus dans ce projet ont le potentiel d'améliorer le choix des stratégies de traitement et donc d'avoir un impact sur la qualité de vie des patients