Gait rehabilitation with an active pelvis orthosis for patients with Parkinson's disease : model-based predictions and assessment of an adaptive framework
(2023)
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- Authors
- Supervisors
- Ronsse, Renaud
- Abstract
- Parkinson's disease is a severe neurodegenerative disorder that affects sensorimotor control, leading to various gait impairments, such as decreased gait speed, stride length, and cadence. These impairments increase the risk of falling and significantly impact the daily lives of affected people. Additionally, they have a decreased level of long-range autocorrelations in series of stride durations, which is a subtle property of gait motor control characterizing natural gait variability. In this context, it is essential to develop innovative therapies that can compensate or mitigate these impairments. Wearable robots - such as active pelvis orthosis - have the potential to be part of this emerging therapeutic toolbox, since they can be used in daily life contexts. In this thesis, we assessed the effects of a walking assistance method relying on adaptive oscillators and delivered by an active pelvis orthosis. This framework is appealing in the context of walking assistance since it naturally adapts to the user's gait features. In this thesis, we first developed model-based predictions about the loss of long-range autocorrelations in the gait of patients with Parkinson's disease, and then we explored the potential of restoring these autocorrelations through the use of the proposed framework relying on oscillator-based walking assistance. This first step demonstrated that this type of assistance has the potential to improve gait variability in patients. Secondly, we examined the impact of this adaptive assistance, which intrinsically tends to normalize the gait pattern, on the level of long-range autocorrelations during walking experiments with healthy subjects. Indeed, many studies have demonstrated in the past that this long-range autocorrelation metric is impacted by external constraints, such as a treadmill or a metronome, or by pathologies, such as Parkinson's or Huntington's diseases. Ten healthy participants, aged between 56 and 77 years, performed four overground walking sessions, wearing the orthosis with different assistive parameters. The results indicated that the adaptive assistance provided by this device can enhance gait metrics typically affected by aging, such as the hip range of motion, walking speed, stride length and duration, without impacting natural gait variability represented by the level of long-range autocorrelations in series of stride durations. These findings hold significant potential for gait rehabilitation in patients with Parkinson's disease, since the gait metrics that are improved by the walking assistance are precisely those that are affected by this disease. In the last part of this thesis, we investigated the influence of the same wearable active pelvis orthosis on the gait of patients with Parkinson's disease. Eight patients with low to moderate disease progression (Hoehn and Yahr stages 1-2.5) performed overground gait training three times per week for four consecutive weeks, assisted by this device. The same metrics examined during the experiments with healthy individuals were assessed before, directly after, and one month after training. The results indicated improvements in hip range of motion, gait speed, stride length, and duration after training, which were maintained one month after its end. Regarding the level of long-range autocorrelations, the population's behavior was standardized towards a value closer to that of healthy individuals after training, but with no retention after one month. This thesis therefore opens the door to the use of oscillator-based walking assistance, adapting in real time to the user's gait kinematics. It also highlights the importance of considering a gait metric characterizing the proper functioning of the locomotor system, i.e., the level of long-range autocorrelations in series of stride durations, throughout the whole rehabilitation pathway.
- Affiliations
Citations
Otlet, V. (2023). Gait rehabilitation with an active pelvis orthosis for patients with Parkinson’s disease : model-based predictions and assessment of an adaptive framework. https://hdl.handle.net/2078.5/29930