The aim of this thesis is to investigate the responses of the neuromuscular system to changes and constraints during explosive multi-segment movements of the lower limbs. The trunk segment was constrained into different positions during pendulum rebound exercises to observe how the neuromuscular system reorganises the movement. It was also aimed to examine how the neuromuscular system coordinates maximal countermovement jumps when the muscle forcegenerating properties of part and all muscles involved in these movements are reduced by the acute effects of fatigue or increased after training. The kinematic characteristics of pendulum rebound exercises were affected by constraining the trunk segment. Greater knee joint angular velocity was achieved when the movements were performed in the upright sitting posture (90) in comparison to the other sitting conditions (135° and 180°). The constraint applied on the trunk segment did not result in the emergence of a particular segmental movement between the hip, knee and ankle joints and variability was observed in the initiation of the joint extension of all rebound conditions. The absence of a fixed order for joint extension initiation showed that sequential and temporal variances can emerge during rebound jumps, where the hip joint, in most cases,e xtendedb efore the other joints. The biarticular musclesw ere suggestedto regulatet he distribution of forces between joints by transporting the large amounts of energy produced by monoarticular muscles, irrespective of the constraints imposed on the trunk segment. It was proposed the existence of a pre-programmed pattern that guides the execution of the movement irrespective of the constraints applied on the trunk segment. Fatiguing part and/or all muscle groups involved in maximal countermovemenjtu mps suggestedt he existence of a common drive that mediates and controls the activation timing between agonistantagonist muscle pairs. A similar muscle activation pattern found after fatigue indicated that the neuromuscular system does not reorganise the co-ordination strategy of explosive movements to compensate for the acute effects of muscular fatigue and acts without the knowledge of the muscle force-generating properties. The decline in the ability of the muscles to produce force was the major factor responsible for the decreases observed in jump height and changes in several kinematic and kinetic variables of the movement. The early occurrence of the peak joint angular velocity may have contributed to jump height decrease and indicated that an "optimal" solution (high countermovement jump performance) was not found under fatigue. It was suggested that training under fatigue should be avoided because the subjects may learn a muscle activation pattern that does not represent an optimal solution. Countermovement jump training (specific stimulus) was more effective than a weight lifting programme (non-specific stimulus) to improve jump height performance. This occurred despite the greater gains in isokinetic peak torque of the knee flexor and extensor muscles achieved after the nonspecific training programme in comparison to the specific training programme. It was observed that the training using non-specific stimulus did not cause the neuromuscular system to reorganise the controls. The neuromuscular system was able to reorganise the movement after the training programme that used a specific stimulus. It was concluded that the increased jump height performance observed after the countermovement jump programme can be attributed to a compounded effect, in which the increased ability of the extensor muscles to generate large amounts of energy around the hip joint was linked to the ability of the biarticular muscles to transfer part of this energy to the distal joints. It was noticed that movement co-ordination changes are sensitive to the order in which the training stimuli are introduced. Jump height performance was improved to a greater extent when the countermovement jumps programme followed the knee extensor and flexor muscles strengthening programme than when the training programmes were introduced in the opposite order.

Magister Scientiae (Physiotherapy) - MSc(Physio) / Background: Globally, the leading cause of lower limb amputation is diabetes mellitus. In South Africa, there is a rise in diabetes-related lower limb amputation with a marked increase in the number of persons with diabetes mellitus in rural areas. However, there is no information on the number of people who are living with a lower limb amputation. An amputation does not only have an impact on a person’s physical functioning but can result in poor quality of life, dependence and exclusion from societal participation. Rehabilitation and prosthetic interventions are known to facilitate those with a lower limb amputation to return to independence in activities of daily living, improved quality of life and inclusion in society. Access to health care is very challenging for persons living in rural areas. Challenges to accessing health care include limited rehabilitation staff, harsh terrain and far distances from services, a lack of access to transport, or the lack of confidence in the service provided by the healthcare institutions. For optimal and patient-centred outcomes, rehabilitation services are of paramount importance. Due to the challenges with providing services in rural areas, community-based rehabilitation is the ideal model for providing rehabilitation to persons with lower limb amputation in rural settings. In order to plan an appropriate community-based approach to rehabilitation, establishing the prevalence of disability and patient-specific needs are imperative. Aims of the study: The aims of this study were firstly, to determine the period prevalence of people living with a lower limb amputation within the rural OR Tambo District of the Eastern Cape in order to determine the need for services and secondly, to gain a deeper understanding of the rehabilitation needs of persons living with a lower limb amputation within the rural OR Tambo District of the Eastern Cape.

Thesis (M.Sc.(Physiotherapy)), Faculty of Health Sciences, University of the Witwatersrand, 2009 / Background: The impact of non-traumatic lower limb amputation on participant’s quality of life (QOL) is unknown. In an effort to provide better care for people with lower limb amputation, there is a need to first know the impact of this body changing operation on people’s quality of life. Aim of the study: To determine the impact of lower limb amputation on QOL in people in the Johannesburg metropolitan area during their reintegration to their society/community of origin. Objectives: 1. To establish the pre-operative and post-operative:  QOL of participants (including the feelings, experiences and impact of lower limb amputation during the time when they have returned home and to the community).  The functional status of participants.  Household economic and social status of these participants. 2. To establish factors influencing QOL. Methods: A longitudinal pre (amputation) test –post (amputation) test study utilized a combination of interviews to collect quantitative data and in-depth semistructured interviews to gather qualitative data. Consecutive sampling was used to draw participants (n=73) for the interviews at the study sites pre-operatively. The three study sites were Chris Hani Baragwanath Hospital, Charlotte Maxeke Johannesburg General Hospital and Helen Joseph Hospital. Participants were then followed up three months later for post-operative interviews and key informants were selected for in-depth interviews (n=12). Inclusion criteria: Participants were included if they were scheduled for first time unilateral (or bilateral amputation done at the same time) lower limb amputation. The participants were between the ages of 36-71 years. Exclusion criteria: Participants who had an amputation as a result of traumatic or congenital birth defects were excluded from the study. Participants with comorbidities that interfered with function pre-operatively were not included. Procedures: Ethics: Ethical clearance was obtained from the Committee for Research on Human Subjects at the University of the Witwatersrand and permission was obtained from the above hospitals. Participants gave consent before taking part in the study. Instrumentation: A demographic questionnaire, the EQ-5D, the Modified Household Economic and Social Status Index (HESSI), the Barthel Index (BI) and semi-structured in-depth interviews were used. Data collection: Participants were approached before the operation for their preoperative interviews using the above questionnaires and then followed up postoperatively using the same questionnaires and some were selected to participate in semi-structured in-depth interviews three months later. Pilot study: The demographics questionnaire and the modified HESSI were piloted to ensure validity and reliability. iii Data analysis: Data were analyzed using the SPSS Version 17.0 and STATA 10.0. The significance of the study was set at p=0.05. All continuous data are presented as means, medians, standard deviations and confidence intervals (CI 95%). Categorical data are presented as frequencies. Pre and post operative differences were analyzed using Wilcoxon Signed-rank test. A median regression analysis (both the univariate and multivariate regression) was done to establish factors influencing QOL. Pre and post operative differences in the EQ-5D items and the BI items were analyzed using Chi square/Fischer’s exact depending on the data. Data were pooled for presentation as statistical figures in tables. Both an intension to treat analysis and per protocol analysis were used. A grounded theory approach was used to analyze the concepts, categories and themes that emerged in the qualitative data. Results: Twenty-four participants (33%) had died by the time of follow up. At three months, n=9 (12%) had been lost to follow up and 40(55%) was successfully followed up. The preoperative median VAS was 60 (n=40). The postoperative median VAS was 70. The EQ-5D items on mobility and usual activities were reported as having deteriorated significantly postoperatively (p=0.04, p=0.001respectively) while pain/discomfort had improved (p=0.003). There was no improvement in QOL median VAS from the preoperative status to three months postoperatively The preoperative median total BI score was (n=40). The postoperative median total BI score was 19. There was a reduction in function (median BI) from the preoperative status to three months postoperatively (p<0.001). The ability to transfer was improved three months postoperatively (p=0.04). Participants were also found to have a decreased ability to negotiate stairs (p<0.001). Mobility was significantly reduced three months postoperatively (p=0.04). During the postoperative stage (n=40), 38% of the participants were married. Most (53%) of the participants had no form of income. The highest percentage of participants in all instances (35%) had secondary education (grade10-11), while 25% had less than grade 5. Only one participant was homeless, 18% lived in shacks, 55% lived in homes that were not shared with other families. People with LLA in the Johannesburg metropolitan area who had no problem with mobility preoperatively (EQ-5D mobility item), who were independent with mobility (BI mobility item) preoperatively, who were independent with transfer preoperatively (BI transfer item) had a higher postoperative quality of life (postoperative median EQ-5D- VAS) compared to people who were dependent or had problems with these functions preoperatively. Being females was a predictor of higher reported quality of life compared to being male. Emerging themes from the qualitative data were psychological, social and religious themes. Suicidal thoughts, dependence, poor acceptance, public perception about body image, phantom limb related falls and hoping to get a prosthesis were reported. Some reported poor social involvement due to mobility problems, employment concerns, while families and friends were found to be supportive. Participants had faith in God. Conclusion: Participants’ QOL and function were generally scored high both preoperatively and postoperatively but there was a significant improvement in QOL and a significant reduction in function after three months although participants were generally still functionally independent. Good mobility preoperatively is a predictor of good QOL postoperatively compared to people with a poor preoperative mobility status Generally, most participants had come to terms with the amputation and were managing well while some expressed that they were struggling with reintegration to their community of origin three months postoperatively with both functional and psychosocial challenges.

The extent to which sensory impairments in the foot, ankle and lower limb persist into the chronic phase of stroke is unclear. Furthermore, the extent to which these impairments influence walking, balance and falls is not well understood. This thesis investigated the prevalence, functional importance and measurement of lower limb somatosensory impairments in ambulatory people with chronic stroke. Methods This thesis comprised three studies: the first, a qualitative investigation, explored the views and experiences of people with chronic stroke (n=13). This led to the second study: a cross sectional observational study in which the prevalence, distribution and functional relevance of lower limb sensory impairments were investigated in chronic stroke participants (n=180) and healthy controls (n=46). The final study, informed by the findings from the first two studies, a “synthesis” review of current sensory measures and patient and carer involvement, developed and evaluated three novel, functionally oriented measures of lower limb somatosensory discrimination in chronic stroke (n=32) and healthy controls (n=32). Results People with stroke felt problems with foot, ankle and lower limb sensation affected their walking, balance and contributed to falls. Furthermore, sensory impairments in the lower limb are prevalent with up to 59% of chronic stroke survivors having a deficit of one or more somatosensory modality. Despite this, weak associations between traditional measures of tactile and proprioceptive sensation and walking, balance and falls were demonstrated. Novel, functionally oriented measures of tactile and proprioceptive discrimination were developed and evaluated. These measures were reliable and valid, showing greater sensitivity to predicting the presence of sensory impairments and had stronger associations with functional measures than traditional sensory tests. Conclusions This thesis has provided a comprehensive picture of lower limb somatosensory dysfunction in chronic stroke survivors. Sensory impairments persist into the chronic phase of stroke in the majority of stroke survivors. The extent to which such impairments influence functional ability warrants further investigation. The use of functionally oriented measures that assess higher-level somatosensation is encouraged.

<p>Subsequent to a difficult surgery or a sever injury to the lower part of the body, often partial </p><p>load bearing is needed to stimulate an optimal rehabilitation. Today, this is achieved by teaching </p><p>the patient the optimal load by iteration. This has been shown insufficient for many patients, due </p><p>to their difficulties of remembering the correct amount of load. Furthermore, patients who lack </p><p>proprioception are unable to feel the load. </p><p> </p><p>A portable measuring system would enhance the patient possibility of optimal loadings. This </p><p>thesis has two main objects. 1. A study of the state of the art on existing commercial system, </p><p>related patents and measuring techniques. 2. A new measuring technique, which is the part that </p><p>most of all determine the system performance, was developed. A new design, using off the shelf, </p><p>products is proposed. </p><p> </p><p>The design uses a finite number of thin sensors placed onto an insole. By placing the sensors at </p><p>the plantar pressure points most of the total load is captured by the insole setups. To compensate </p><p>for the measuring error fitting methods were evaluated. The result depends on the insole </p><p>calibration methods. The best result without individual calibration is: mean error for the group of </p><p>0.5% of the total patient load and a deviation of 24%. With individual calibration reduces the </p><p>deviation to about 12%.</p>

Subsequent to a difficult surgery or a sever injury to the lower part of the body, often partial load bearing is needed to stimulate an optimal rehabilitation. Today, this is achieved by teaching the patient the optimal load by iteration. This has been shown insufficient for many patients, due to their difficulties of remembering the correct amount of load. Furthermore, patients who lack proprioception are unable to feel the load. A portable measuring system would enhance the patient possibility of optimal loadings. This thesis has two main objects. 1. A study of the state of the art on existing commercial system, related patents and measuring techniques. 2. A new measuring technique, which is the part that most of all determine the system performance, was developed. A new design, using off the shelf, products is proposed. The design uses a finite number of thin sensors placed onto an insole. By placing the sensors at the plantar pressure points most of the total load is captured by the insole setups. To compensate for the measuring error fitting methods were evaluated. The result depends on the insole calibration methods. The best result without individual calibration is: mean error for the group of 0.5% of the total patient load and a deviation of 24%. With individual calibration reduces the deviation to about 12%.

The study is to propose a novel design for the lower limb rehabilitation system through the motion training of stepping upward or downward. A main goal of this design is to constrain the system dimension to a small value for home use purpose. It is also desired that the functioning of system is automatic that the direction of stepping upward or downward can be changed arbitrarily in the training process. The TRIZ theory, which offers a systematic thinking process for problem solving, is adopted in this study to construct the first step of conceptual design. From the theory, the problems of system design is mainly to deal with three issues, which are the spatial analysis and optimization, motion conversion design for ladder, and the motion control of ladder. The spatial analysis is to investigate the optimal trajectory of ladder motion that the total space of the system can be minimized. It is done by assuming a specific geometrical property of ladder trajectory and solving the optimization problem through the parameter optimization. The motion conversion design is to invent an approach to change the configuration of ladder from either open-to-close or close-to-open status. To do so, a small section of ladder trajectory is asked to be flexible and a mechanism to trigger the configuration change is proposed. The motion control is to maintain the user located in an almost same location while the training is preceded. In this study, the PID control scheme is adopted to examine whether the control goal can be properly achieved. This study reveals that a proper design can be obtained through the specific process of problem solving. The system is shown to function well when the above three issues are solved by the proposed schemes.

The long-term goal of this study is to improve the ability of designers and prosthetists to match the mechanical characteristics of prosthetic feet to patient specific parameters, including, needs, abilities and biomechanical characteristics. While patient measures of performance are well developed, there is a need to develop a practical method by which non-linear and time-dependent mechanical properties of the prosthetic component can be measured. In this study, testing methodologies were developed that separately evaluated the elastic and time-dependent properties. Three styles of feet were tested to span the range of designs of interest: a standard solid ankle cushioned heel (SACH) foot, two energy return feet for active users and a new prosthetic foot designed to provide partial energy return. The first testing regime involved mechanically characterizing prostheses under conditions similar to gait. The heels and toes of four sample feet were loaded to peak forces based on their design mass at a series of angles and forces that the prosthetic system would go through during the gait cycle, based on the waveform in ISO 22675. Tangential stiffnesses of the samples were determined using numerical differentiation. The force-displacement responses of prosthetic feet reflect increasing stiffnesses with increasing loads and a decreasing pylon angle. Key features reflecting foot design are: the relative stiffness of the heel and toe and the displacement gap at midstance. Stable feet tend to exhibit lower heel stiffnesses and higher toe stiffnesses, whereas dynamics energy return (DER) feet tend to exhibit higher heel stiffnesses and lower toe stiffnesses. The differences in heel and toe loading at midstance suggest that DER feet can aid in the transition from heel to toe, providing a smooth rollover whereas SACH feet provide greater stability. A second testing regime examined the time-dependent properties of the heel and toe. A three-parameter reduced relaxation response of the form was able to capture the force-relaxation characteristics with RMS differences ranging from 0.0006 to 0.0119. In this model, A is the initial decay, B is the decay coefficient, a linear decay term, and τ is a time constant. While the model is practical for comparing various prostheses at a single load level, a fully non-linear model is required to model the time-dependent response at all loading levels. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2008-04-16 11:27:02.51 / Otto Bock® Dupont Niagara Prothetics and Orthotics International Health Technology Exchange (HTX) Ontario Centres of Excellence

Stair negotiation has been identified by older adults as one of the most challenging locomotor tasks, one that is associated with a high risk for falls and serious injury. Currently lacking is a comprehensive understanding of the lower limb during stair negotiation in an older adult population. It has been identified that more research is needed to determine key determinants of difficulty and safety on stairs. The objective of this thesis was to investigate lower limb kinematics and kinetics during stair negotiation and evaluate the impact of handrail use on stair ambulation in young adults, older adults, and older adults with a fear of falling (FOF). The four studies that make up this dissertation provide a detailed picture of the lower limb joint kinematics and kinetics during stair ambulation, as well as provide insight into the role of handrail use and FOF in performance of stair negotiation. Specifically, in the first study principal component analysis (PCA) was used, of the scores generated from the PCA models four principal component (PC) scores were identified that could be used to correctly classify 95% of young and older adults. The second study provided a comprehensive data set of lower limb joint kinematics and kinetics during stair negotiation. The third study identified comparable centre of pressure velocities (VCOP) between young adults and older adults during stair negotiation with and without a handrail. Whereas older adults with FOF demonstrated reduced VCOP during stair negotiation without a handrail and further reduced VCOP when using the handrail. Furthermore, no significant difference in lower limb moments during stair negotiation with and without a handrail were found in older adults, as was similar for older adults with FOF. However, a gait assessment revealed that older adults with FOF demonstrated differences from ‘normal’ gait patterns during stair negotiation with and without a handrail. These studies provide a comprehensive normative dataset of the lower limb joint kinematics and kinetics during stair negotiation, as well as provide insight into the role of handrail use and fear of falling in performance of stair ambulation. It is important to appreciate the nature and extent of normal age-related adaption and compensatory strategies to identify unique patterns of movement due to the superimposition of pathology. / Thesis (Ph.D, Kinesiology & Health Studies) -- Queen's University, 2010-09-24 14:50:22.242

Masters of Science - Msc (Physiotherapy) / Vocational rehabilitation relates to rehabilitating a person with an amputation back into actively participating in society. Although vocational rehabilitation is important, before it can be implemented, the participation restrictions should be identified. Even though lower limb amputation surgery is commonly performed in South Africa, and given the high unemployment rate in the country, no research has been done into the participation restrictions and vocational needs of a person with a unilateral lower limb amputation in the Western Cape. The aim of this study was to determine and explore the participation restrictions and vocational rehabilitation needs in terms of hobbies, sport activities, employment and employment needs of persons with a unilateral lower limb amputation (LLA) in the Western Cape. The objectives were to: 1) Determine the participation restrictions of persons with a unilateral LLA in the Western Cape. 2) To explore the vocational rehabilitation needs of persons with a lower limb amputation. A mixed methods approach, and an explanatory sequential design was used in this study. The study was conducted in two phases. The first phase utilised a quantitative approach and the WHODAS 2.0 was used as the instrument to collect data. The second phase aimed to explain the data collected in the first phase in more depth, and semi-structured telephonic interviews were utilized to collect the qualitative data. The study was set in the Cape Metropole region of the Western Cape. Participants were recruited from Tygerberg Tertiary Hospital and a private sub-acute rehabilitation centre. In the quantitative (first) phase of the study, 50 participants were conveniently recruited to participate. In the second phase eight participants were purposefully selected from the pool of 50 participants from the first phase of the study who consented to participate in the second phase. Quantitative data was analysed using SPSS vs. 22 and analysed for descriptive and inferential statistics. Qualitative data has been analysed using Creswell's seven step process of thematic analysis. Ethical clearance has been obtained from the University of the Western Cape, permission to access patients' details has been obtained from Tygerberg Tertiary Hospital and private sub-acute rehabilitation centre. Written informed consent as well as permission for audio recording during the telephonic interview was obtained.