Clinical evaluation of a mobile sensor-based gait analysis method for outcome measurement after knee arthroplasty

Clinical scores and motion-capturing gait analysis are today’s gold standard for outcome measurement after knee arthroplasty, although they are criticized for bias and their ability to reflect patients’ actual quality of life has been questioned. In this context, mobile gait analysis systems have been introduced to overcome some of these limitations. This study used a previously developed mobile gait analysis system comprising three inertial sensor units to evaluate daily activities and sports. The sensors were taped to the lumbosacral junction and the thigh and shank of the affected limb. The annotated raw data was evaluated using our validated proprietary software. Six patients undergoing knee arthroplasty were examined the day before and 12 months after surgery. All patients reported a satisfactory outcome, although four patients still had limitations in their desired activities. In this context, feasible running speed demonstrated a good correlation with reported impairments in sports-related activities. Notably, knee flexion angle while descending stairs and the ability to stop abruptly when running exhibited good correlation with the clinical stability and proprioception of the knee. Moreover, fatigue effects were displayed in some patients. The introduced system appears to be suitable for outcome measurement after knee arthroplasty and has the potential to overcome some of the limitations of stationary gait labs while gathering additional meaningful parameters regarding the force limits of the knee

Exploring Innovative Rehabilitation for the Knee using Ehealth, Biofeedback and Online Communities

Knee pain is regarded as an inevitable outcome in an ageing population and subsequent management, treatment and rehabilitation may exacerbate demand on stretched health services globally. Knee pain can be influenced by a number of factors; gender, body mass, activity profile, arthrokinematics, patient biopsychosociology and predisposing injury or trauma. Treatment options are typically viewed as pharmacological and non-pharmacological. Exercise and physical therapy are key elements within the latter option, alongside surgical procedures. Knee pain sufferers may vindicate their condition through clinical diagnosis and shift of locus of control; compliance to exercise interventions can depend on the scope of this shift. Such values should be acknowledged when monitoring individualised progression in the management of knee pain. Technology may have a role to play in capturing and influencing compliance within the scope of knee rehabilitation. The main aim of this thesis was to explore the use of innovative rehabilitation interventions for the knee that integrated eHealth, biofeedback and online communities. As this constitutes a complex scenario, this thesis has been reported using elements of the Medical Research Council (MRC) framework for the development and evaluation of complex interventions to improve health (Blackwood et al., 2010; Craig et al., 2008); notably the Preclinical (theory) stage, the Phase I (modelling) stage, and Phase II (exploratory trial). The findings further inform the options for rehabilitation around knee pain, encompassing latest generation techniques for addressing progressive joint disease and eHealth initiatives. These also included options for self-management and reporting that could be generalised to knee pain sufferers; an approach informed by the exploration of the reported experiences of individuals engaging with an online health community for knee pain. The eHealth component of the thesis looked to explore the use of simple Web 2.0 solutions and readily available domiciliary equipment for efficacy and accessibility

Biomechanical Evaluations of Bilateral and Unilateral TKR Patients During Level Walking and Stair Negotiation

Many total knee replacement (TKR) patients will need to have a contralateral knee replacement. Biomechanical differences between 1st and 2nd replaced limbs of bilateral TKR have not been examined during level walking or stair negotiation. Further, it is unknown if hip and ankle biomechanics of bilateral patients are altered, compared to the replaced and non-replaced limbs of unilateral patients during level walking and stair negotiation. Study one and two compared hip, knee, and ankle biomechanics of the 1st and 2nd replaced limbs of bilateral patients and both replaced and non-replaced limbs of unilateral patients during level walking and stair negotiation, respectively. Study three compared knee joint waveforms of the 1st replaced limbs of bilateral patients, replaced limbs of unilateral patients, and randomly selected limbs of asymptomatic controls during level walking. Study one found that 2nd replaced limbs exhibited lower peak loading-response knee extension moments than the first replaced limbs. Bilateral patients exhibited lower loading-response knee extension moments, knee abduction moments, and dorsiflexion moments, compared to unilateral patients. Bilateral patients also exhibited lower push-off peak hip flexion moments and vertical GRF. Study two found during ascent, bilateral patients exhibited decreased peak loading-response knee extension (KEM) and push-off plantarflexion moments. Unilateral replaced limbs KEM was lower than non-replaced. During descent, bilateral patients descended significantly slower, had lower peak loading-response vertical GRF and KEM, and push-off KEM. Bilateral patients had higher peak loading-response hip extension and push-off plantarflexion moments, and increased knee adduction ROM. Study three found TKR patients exhibited more flexed and abducted knees throughout stance, decreased sagittal knee ROM, increased early-stance adduction ROM, decreased LR knee extension and PO knee flexion moments, decreased LR and PO KAbM, increased KAbM at midstance, increased midstance vertical GRF, as well as decreased LR and PO vertical GRF. Additionally, bilateral patients exhibited reduced sagittal knee ROM, increased adduction ROM, decreased sagittal knee moments throughout stance, decreased KAbM throughout stance, an earlier LR peak vertical GRF, and a decreased PO vertical GRF, compared to unilateral patients