Motor patterns evaluation of people with neuromuscular disorders for biomechanical risk management and job integration/reintegration

Neurological diseases are now the most common pathological condition and the leading cause of disability, progressively worsening the quality of life of those affected. Because of their high prevalence, they are also a social issue, burdening both the national health service and the working environment. It is therefore crucial to be able to characterize altered motor patterns in order to develop appropriate rehabilitation treatments with the primary goal of restoring patients' daily lives and optimizing their working abilities. In this thesis, I present a collection of published scientific articles I co-authored as well as two in progress in which we looked for appropriate indices for characterizing motor patterns of people with neuromuscular disorders that could be used to plan rehabilitation and job accommodation programs. We used instrumentation for motion analysis and wearable inertial sensors to compute kinematic, kinetic and electromyographic indices. These indices proved to be a useful tool for not only developing and validating a clinical and ergonomic rehabilitation pathway, but also for designing more ergonomic prosthetic and orthotic devices and controlling collaborative robots

Assessing Performance, Role Sharing, and Control Mechanisms in Human-Human Physical Interaction for Object Manipulation

abstract: Object manipulation is a common sensorimotor task that humans perform to interact with the physical world. The first aim of this dissertation was to characterize and identify the role of feedback and feedforward mechanisms for force control in object manipulation by introducing a new feature based on force trajectories to quantify the interaction between feedback- and feedforward control. This feature was applied on two grasp contexts: grasping the object at either (1) predetermined or (2) self-selected grasp locations (“constrained” and “unconstrained”, respectively), where unconstrained grasping is thought to involve feedback-driven force corrections to a greater extent than constrained grasping. This proposition was confirmed by force feature analysis. The second aim of this dissertation was to quantify whether force control mechanisms differ between dominant and non-dominant hands. The force feature analysis demonstrated that manipulation by the dominant hand relies on feedforward control more than the non-dominant hand. The third aim was to quantify coordination mechanisms underlying physical interaction by dyads in object manipulation. The results revealed that only individuals with worse solo performance benefit from interpersonal coordination through physical couplings, whereas the better individuals do not. This work showed that naturally emerging leader-follower roles, whereby the leader in dyadic manipulation exhibits significant greater force changes than the follower. Furthermore, brain activity measured through electroencephalography (EEG) could discriminate leader and follower roles as indicated power modulation in the alpha frequency band over centro-parietal areas. Lastly, this dissertation suggested that the relation between force and motion (arm impedance) could be an important means for communicating intended movement direction between biological agents.Dissertation/ThesisDoctoral Dissertation Biomedical Engineering 201

ISBS 2018 AUCKLAND CONFERENCE SCHEDULE FINAL

This document contains the ISBS 2018 Auckland Conference Schedule of keynotes, oral podiums, oral posters, social events, workshops, SPRINZ-HPSNZ-AUT Millennium applied half day and teachers day

The contemporary model of vertebral column joint dysfunction and impact of high-velocity, low-amplitude controlled vertebral thrusts on neuromuscular function

Peer reviewedPublisher PD

Fusion, 2018

https://hsrc.himmelfarb.gwu.edu/smhs_fusion/1010/thumbnail.jp

Quantifying and predicting upper limb capability and dysfunction of breast cancer survivors

Breast cancer will affect one in every nine Canadian women during their lifetime. As diagnostic and treatment methods improve, survival rates are approaching 90%. However, an alarming 30-82% of survivors suffer from persistent upper limb morbidity as a result of their cancer treatments (Kwan, Jackson, Weir, Dingee, McGregor, & Olivotto, 2002; Lauridsen, Overgaard, Overgaard, Hessov, & Cristiansen, 2008; Rietman, Dijkstra, Debreczeni, Geertzen, Robinson, & De Vries, 2004). These persistent disabilities compromise function and quality of life, hindering survivors from returning to work and leading functional and independent lives. In order to prevent and rehabilitate upper limb morbidities, quantification of the physical capabilities of this population must occur. This thesis quantified the upper limb physical capabilities and limitations of breast cancer survivors by producing the most comprehensive collection of 3-D kinematics, muscle activation patterns, muscle-specific strength, and quality of life and disability measures during a wide range of functional tasks. Compared to the contralateral limb, the affected side demonstrated reduced humeral elevation (-6.5°) and external rotation angles (-8.9°), increased humeral internal rotation (+13.1°), reduced scapular protraction (-3.9°) (although both sides demonstrated protraction), increased upward rotation (+2.8°) and increased posterior tilting (+4.1°) of the scapula. These relationships varied with the task being performed. Muscle activation patterns revealed increased total muscle effort on the affected side during work tasks (p = 0.0258), and reductions in pectoralis major sternal activation (p<0.0001 – p = 0.0230). Increased muscle effort, weakness and discomfort levels were evident in both primary and secondary muscles (muscles outside the field of surgery and radiation). Humeral internal (IR) and external rotation (ER) co-activation was defined in both healthy (H) and breast cancer survivor populations (BCP) (H: r2 = 0.70 (IR) and 0.35 (ER); BCP: r2 = 0.77 (IR) and 0.77 (ER)). Humeral abduction angle and task intensity were important factors in the prediction of co-activation in both populations. Inclusion of physiological cross-sectional area (PCSA) weightings did not sufficiently improve the representation of co-activation in the healthy population. Healthy co-activation relationships were successfully extrapolated to a novel set of IR exertions (r2 = 0.76 IR exertions; r2 = 0.40 ER exertions). Comparisons made between populations identified differing muscle strategies used by survivors to maintain glenohumeral joint stability. Compared to healthy population co-activation, the survivors demonstrated greater activation of IR and ER muscles during their respective rotation type. Survivors demonstrated increased (≤8.7%) activation of pectoralis major muscle activation compared to the healthy population. An optimization-based muscle force prediction model was used to reflect specific muscle dysfunction of the pectoralis major muscles, and population-specific co-activation was enforced as a constraint. Empirically measured EMG was more closely associated to muscle force predictions of external rotator muscles (r = 0.567) than internal rotator muscles (r = 0.347). Model predictions were influenced by exertion type, co-activation constraint, hand force and pectoralis major capability constraints. The model predicted muscle forces more closely to empirical measurements of activation when the co-activation constraint was enforced, emphasizing the importance of consideration of antagonistic muscle activation in biomechanical modeling. This comprehensive description of physical capabilities of the breast cancer population has never been performed in such detail. This body of work has furthered the knowledge available regarding the capacity and functional limitations of survivors and preliminary recommendations regarding therapeutic treatment and directions for future works have been suggested. The continued development of this research and future application of interventions designed to address these disabilities will promote the eventual return to function and work of survivors through targeted rehabilitation and treatment strategies. Development of effective rehabilitation and prevention strategies could potentially lower the social and economic burdens of survivor aftercare and dramatically enhance the quality of life of survivors, allowing them to lead highly functional and independent lives