Assessing Ground Reaction Forces and Degenerative Changes of Sound Limb in Unilateral Lower Extremity Amputees: A Systematic Review

Abstract Background: There is a rising number of individuals undergoing lower extremity amputation (LEA) and is associated with increased risk of comorbidities. Osteoarthritis (OA) and Degenerative Joint Disease (DJD) are conditions that cause reduction in an individual’s function, independence, and quality of life. Research Design: A search of multiple databases using terms associated with possible functional declines as evidenced by the International Classification of Functioning, Disability and Health (ICF), followed by assessment of evidence using the PEDro scoring method will be conducted. Multiple reviewers will screen, sort, rate and extract data from articles. Methods: A computer-aided literature search of PubMed, CINAHL, and Google Scholar was performed to identify studies published beginning in 2009 that investigated factors that contribute to degenerative changes in the contralateral limb of a unilateral LEA. Results: A total of 21 studies were selected from a total of 56 collected studies. Predictors of osteoarthritis (OA) following lower limb amputation include age, etiology, level of amputation, gender, Body Mass Index (BMI), comorbidity, pain, phantom pain, streng and OA. The impact of ground reaction forces on the sound limb varies between studies. In general, poor gait mechanics and resulting compensatory mechanisms are significant contributors to the occurrence of OA. Conclusion: There is a dearth of information relating to the prevention of degenerative changes in those with LEA and protocols for pain management and training pre- and post-joint replacement. The incidence of OA in the contralateral limb is still not fully understood. Further investigation into the biomechanics of compensatory mechanisms is necessary to fully understand the functional impact on the population. It is imperative to develop thorough physical therapy protocols for individuals in early onset of OA and those undergoing joint replacement due to degeneration

The Impact of Anterior Cruciate Ligament Reconstructive Surgery on Neuromotor Function

The purpose of this dissertation was to examine the systemic neuromechanical implications in individuals who have had an ACL reconstruction (ACLR) compared to healthy controls. The specific aims addressed were to: 1) examine differences in inter-limb coordination during walking at different speeds, 2) examine differences in trunk, neck and head acceleration during gait, and 3) investigate whether the reaction time responses assessed during stepping are negatively affected by ACLR. The findings of study 1 revealed that maximal coordination stability was achieved when walking at the person’s preferred gait speed. However, individuals with a previous ACLR exhibited reduced coordination stability between the knees, indicative of decreased inter-limb coupling. Further, individuals within the ACLR group who deviated the most from anti-phase coordination during walking also demonstrated lower coordination stability. These findings could contribute to the secondary issues related to ACL damage. Study two examined differences in upper body accelerations during gait, revealing that the ACLR group had a diminished capacity to attenuate gait-related oscillations from the trunk to the head. Further, the vertical acceleration signals for the ACLR individuals were more complex, indicating that they had a reduced ability to optimally accelerations during walking. These results demonstrate the impact of ACL damage is not localized but is more systemic and can negatively impact postural control. The third study assessed how ACLR would impact of general neuromotor function and stepping reaction times. The findings revealed that ACLR individuals had slower reaction times during stepping compared to healthy controls. In contrast to the slowing of reaction time (under postural conditions), there were no changes across any other neuromotor/mechanical measures. This result indicates that the ACLR group had a reduced ability to respond to unexpected stimuli. Overall, the results of this investigation suggest that ACL damage has a wide-spread impact as it not simply localized to the injured knee. The collective results from these studies show changes in movement strategy prioritization in those with an ACLR. These novel findings provide an alternate perspective and may change the ways in which clinicians and healthcare providers assess individuals who have had ACL reconstructive surgery

Differential activation of lumbar and sacral motor pools during walking at different speeds and slopes

Organization of spinal motor output has become of interest for investigating differential activation of lumbar and sacral motor pools during locomotor tasks. Motor pools are associated with functional grouping of motoneurons of the lower limb muscles. Here we examined how the spatiotemporal organization of lumbar and sacral motor pool activity during walking is orchestrated with slope of terrain and speed of progression. Ten subjects walked on an instrumented treadmill at different slopes and imposed speeds. Kinetics, kinematics, and electromyography of 16 lower limb muscles were recorded. The spinal locomotor output was assessed by decomposing the coordinated muscle activation profiles into a small set of common factors and by mapping them onto the rostrocaudal location of the motoneuron pools. Our results show that lumbar and sacral motor pool activity depend on slope and speed. Compared with level walking, sacral motor pools decrease their activity at negative slopes and increase at positive slopes, whereas lumbar motor pools increase their engagement when both positive and negative slope increase. These findings are consistent with a differential involvement of the lumbar and the sacral motor pools in relation to changes in positive and negative center of body mass mechanical power production due to slope and speed.NEW & NOTEWORTHY In this study, the spatiotemporal maps of motoneuron activity in the spinal cord were assessed during walking at different slopes and speeds. We found differential involvement of lumbar and sacral motor pools in relation to changes in positive and negative center of body mass power production due to slope and speed. The results are consistent with recent findings about the specialization of neuronal networks located at different segments of the spinal cord for performing specific locomotor tasks

An explorative study of factors influencing health-related quality of life in patients with femoral fractures

Includes abstract. Includes bibliographical references

Spatial Sensors for Quantitative Assessment of Retrieved Arthroplasty Bearings

Evaluation of retrieved joint arthroplasty bearings provides unique evidence related to the physiological environment in which bearing materials are expected to perform. This dissertation describes the development of novel spatial sensors and measurement strategies for standardized, quantitative assessments of arthroplasty bearings, including total knee replacements, unicompartmental knee replacements, and total hip replacements. The approach is to assess bearings that endured a finite duration of function in patients, with particular emphasis on expanding our understanding of the biomechanical conditions specific to bearing function and wear in the physiological environment. Several quantifiable parameters are identified that prove comparable to pre-clinical in vitro tibological evaluations, including knee wear simulation and analytical modeling. These comparisons provide clinical relevance to the existing methodologies, helping to verify that the biomechanical simulations accurately represent the in vivo conditions they are meant to simulate. The broad objective of this dissertation is to improve the longevity and function of arthroplasty bearing materials and designs. Assessments from the retrieved prostheses are discussed within the context of developing comprehensive approaches for the prospective evaluation of new materials and designs in joint replacements

Book of Abstracts 15th International Symposium on Computer Methods in Biomechanics and Biomedical Engineering and 3rd Conference on Imaging and Visualization

In this edition, the two events will run together as a single conference, highlighting the strong connection with the Taylor & Francis journals: Computer Methods in Biomechanics and Biomedical Engineering (John Middleton and Christopher Jacobs, Eds.) and Computer Methods in Biomechanics and Biomedical Engineering: Imaging and Visualization (JoãoManuel R.S. Tavares, Ed.). The conference has become a major international meeting on computational biomechanics, imaging andvisualization. In this edition, the main program includes 212 presentations. In addition, sixteen renowned researchers will give plenary keynotes, addressing current challenges in computational biomechanics and biomedical imaging. In Lisbon, for the first time, a session dedicated to award the winner of the Best Paper in CMBBE Journal will take place. We believe that CMBBE2018 will have a strong impact on the development of computational biomechanics and biomedical imaging and visualization, identifying emerging areas of research and promoting the collaboration and networking between participants. This impact is evidenced through the well-known research groups, commercial companies and scientific organizations, who continue to support and sponsor the CMBBE meeting series. In fact, the conference is enriched with five workshops on specific scientific topics and commercial software.info:eu-repo/semantics/draf

Recognizing complex faces and gaits via novel probabilistic models

In the field of computer vision, developing automated systems to recognize people under unconstrained scenarios is a partially solved problem. In unconstrained sce- narios a number of common variations and complexities such as occlusion, illumi- nation, cluttered background and so on impose vast uncertainty to the recognition process. Among the various biometrics that have been emerging recently, this dissertation focus on two of them namely face and gait recognition. Firstly we address the problem of recognizing faces with major occlusions amidst other variations such as pose, scale, expression and illumination using a novel PRObabilistic Component based Interpretation Model (PROCIM) inspired by key psychophysical principles that are closely related to reasoning under uncertainty. The model basically employs Bayesian Networks to establish, learn, interpret and exploit intrinsic similarity mappings from the face domain. Then, by incorporating e cient inference strategies, robust decisions are made for successfully recognizing faces under uncertainty. PROCIM reports improved recognition rates over recent approaches. Secondly we address the newly upcoming gait recognition problem and show that PROCIM can be easily adapted to the gait domain as well. We scienti cally de ne and formulate sub-gaits and propose a novel modular training scheme to e ciently learn subtle sub-gait characteristics from the gait domain. Our results show that the proposed model is robust to several uncertainties and yields sig- ni cant recognition performance. Apart from PROCIM, nally we show how a simple component based gait reasoning can be coherently modeled using the re- cently prominent Markov Logic Networks (MLNs) by intuitively fusing imaging, logic and graphs. We have discovered that face and gait domains exhibit interesting similarity map- pings between object entities and their components. We have proposed intuitive probabilistic methods to model these mappings to perform recognition under vari- ous uncertainty elements. Extensive experimental validations justi es the robust- ness of the proposed methods over the state-of-the-art techniques.

Constraints on coordination:Intrinsic dynamics, behavioral information and asymmetry in bimanual rhythmic coordination

Zonder oefening is het met pianospelen vrijwel onmogelijk om de handen onafhankelijk van elkaar te bewegen. De handbewegingen zijn op een bepaalde manier gekoppeld. Martine Verheul onderzocht hoe dat precies zit. Daarvoor liet ze haar proefpersonen met twee handen verschillende ritmes tikken. Naast persoonsgebonden verschillen blijken er ook taak-afhankelijke verschillen te zijn. Muzikale ervaring van de proefpersoon had een positief effect op de stabiliteit van tweehandige ritmische coördinatie. Daarna vergeleek Verheul links- en rechtshandigen bij het tikken van symmetrische en asymmetrische patronen. In tegenstelling tot taken waarbij de handen in verschillend tempo tikken blijkt bij het asymmetrisch tikken in een gelijk tempo de coördinatie even stabiel in beide handverdelingen. Verheul toont aan dat zowel de voorkeurshand als de niet-voorkeurshand de leidende rol op zich kan nemen. Die flexibiliteit vermindert echter bij het ouder worden. De coördinatieproblemen bij volwassenen met de ziekte van Parkinson komen niet voort uit de asymmetrische verdeling van symptomen over de twee lichaamshelften, maar zijn volgens Verheul het gevolg van centrale problemen met het koppelen van de ledematen.

Locomotion Trajectory Generation and Dynamic Control for Bipedal Walking Robots

Ph.DDOCTOR OF PHILOSOPH