A clubfoot is characterized by a three-dimensional deformity with an equinus, varus, cavus and adduction component. Nowadays the Ponseti method is the preferred treatment for clubfeet, aiming to achieve a normal appearing, functional and painless foot. The reoccurrence of clubfoot components in treated clubfeet, a relapse, is a known problem in clubfoot patients. 3Dgait analysis can be used in assessment of foot function and residual deviations in gait or possible relapses. Gait analysis is frequently used to analyse differences in gait between clubfoot and healthy controls. However, the usage of multisegment foot models is, although of importance considering the characteristics of the clubfoot, rare. In order to capture the full multi-planar and multi-joint nature of a clubfoot, it is highly important to implement multi-segment foot models in gait analysis. In order to improve treatment of individual relapse clubfoot kinematics differences in clinical relevant functional outcomes should be known.
PURPOSE: To compare the responses in knee joint muscle activation patterns to different perturbations during gait in healthy subjects.SCOPE: Nine healthy participants were subjected to perturbed walking on a split-belt treadmill. Four perturbation types were applied, each at five intensities. The activations of seven muscles surrounding the knee were measured using surface EMG. The responses in muscle activation were expressed by calculating mean, peak, co-contraction (CCI) and perturbation responses (PR) values. PR captures the responses relative to unperturbed gait. Statistical parametric mapping analysis was used to compare the muscle activation patterns between conditions.RESULTS: Perturbations evoked only small responses in muscle activation, though higher perturbation intensities yielded a higher mean activation in five muscles, as well as higher PR. Different types of perturbation led to different responses in the rectus femoris, medial gastrocnemius and lateral gastrocnemius. The participants had lower CCI just before perturbation compared to the same phase of unperturbed gait.CONCLUSIONS: Healthy participants respond to different perturbations during gait with small adaptations in their knee joint muscle activation patterns. This study provides insights in how the muscles are activated to stabilize the knee when challenged. Furthermore it could guide future studies in determining aberrant muscle activation in patients with knee disorders.
BackgroundGait analysis has been used for decades to quantify knee function in patients with knee osteoarthritis; however, it is unknown whether and to what extent inter-laboratory differences affect the comparison of gait data between studies. Therefore, the aim of this study was to perform an inter-laboratory comparison of knee biomechanics and muscle activation patterns during gait of patients with knee osteoarthritis.MethodsKnee biomechanics and muscle activation patterns from patients with knee osteoarthritis were analyzed, previously collected at Dalhousie University (DAL: n = 55) and Amsterdam UMC, VU medical center (VUmc: n = 39), using their in-house protocols. Additionally, one healthy male was measured at both locations. Both direct comparisons and after harmonization of components of the protocols were made. Inter-laboratory comparisons were quantified using statistical parametric mapping analysis and discrete gait parameters.ResultsThe inter-laboratory comparison showed offsets in the sagittal plane angles, moments and frontal plane angles, and phase shifts in the muscle activation patterns. Filter characteristics, initial contact identification and thigh anatomical frame definitions were harmonized between the laboratories. After this first step in protocol harmonization, the offsets in knee angles and sagittal plane moments remained, but the inter-laboratory comparison of the muscle activation patterns improved.ConclusionsInter-laboratory differences obstruct valid comparisons of gait datasets from patients with knee osteoarthritis between gait laboratories. A first step in harmonization of gait analysis protocols improved the inter-laboratory comparison. Further protocol harmonization is recommended to enable valid comparisons between labs, data-sharing and multicenter trials to investigate knee function in patients with knee osteoarthritis.
MULTIFILE
The clubfoot deformity is one of the most common congenital orthopaedic “conditions”. Worldwide approximately 100,000 children are born with unilateral or bilateral clubfoot every year. In the Netherlands the incidence is approximately 175 every year. This three dimensional deformity of the foot involves, equinus, varus, adductus, and cavus . Left untreated the clubfoot leads to deformity, functional disability and pain. Physical impairments of children with clubfoot might lead to limitations in activities and therefore impede a child’s participation. In clinical practice, the orthopaedic surgeon and physiotherapists are regularly consulted by (parents of) clubfoot patients for functional problems such as impaired walking and other daily activities. This does not only affect long-term and physical health of a child, it will also affect the development of social relationships and skills as well. Since walking is a main activity in children to be able to participate in daily life, our previous study (financially supported by SIA Raak Publiek) focussed on gait differences between children with clubfoot and controls. However, differences in gait characteristics do not necessarily lead to functional limitations and restricted participation. Therefore, providing insight in participation and a child’s performance in other activities than walking is necessary. Insight in a child’s participation will also indicate the functional outcome of the treatment, which on its turn could provide essential information concerning a possible relapse.. Early identification of a relapse is important since it could prevent the need for major surgical interventions. The occurrence of a relapse clubfoot will probably also lead to functional differences in the foot as well as problems during activity and participation. Therefore, the main focus of this study is the functional outcomes of physical activities and the characterisation of participation of children with clubfeet in daily activities of childhood.
