A computational design of lower limb amputee rehabilitation using functional electrical stimulation

There are more than one million annual amputations globally as a result of vascular diseases, trauma and cancer. Due to the increasing rate of diabetes and the population ageing, a growth of amputation is expected with the prediction that the amputee population will double by 2050. A prosthesis allows a certain restoration of functional mobility after an amputation. However, neither passive nor active prostheses can directly address the fundamental problems of chronic pain and muscle atrophy in millions of amputees worldwide. Chronic amputation-related pain impairs function. In addition, the early decline in the use of the affected limb results in progressive muscle atrophy with strength loss. Concurrently, a mechanical adaption occurs in order to compensate for the collective effects due to limb loss. A common compensation strategy is to overload the intact limbs in terms of time and intensity, which will cause secondary musculoskeletal disorders, further compromising their health-related quality of life.
The project will target the clear unmet needs of amputees by developing a novel functional electrical stimulation (FES) device. A ground-breaking, computational approach based on predictive musculoskeletal modelling will be developed and integrated into the device to design patient-centred rehabilitation. This device has the potential to prescribe the optimal rehabilitation protocol in pain management and mobility enhancement; its long-term application will prevent the onset and progress of musculoskeletal disorders and ultimately improve the quality of life. Dr Ding will receive support from a multidisciplinary team of researchers, business experts, clinicians and patients to ensure the project will impact various stakeholders.
Patients: given the high risk of multiple complications after an amputation, the development of such a new generation of therapies will be attractive to millions of amputees worldwide. Of further importance, are the costs of amputee rehabilitation services. To a civilian amputee, the rehabilitation cost in the first 5 years is approximately $107,200. To the military amputees, the costs will be even higher as they are younger at the time of injury and societal costs will be incurred over a longer period. As such, to prove the efficacy of the novel device in amputee rehabilitation will have a significant socioeconomic impact.
Clinicians: the computational rehabilitation design has the potential to enhance clinical decision making in the rehabilitation pathway. By modelling individual patient's performance and predicting the outcomes in the in-silico environment, the modelling approach will improve patient's satisfaction to current practice. The project will create a collaborative environment for engineers and clinicians to share intellectual investment and make a broad impact of computational modelling and simulation in the clinic.
Medical device industry: the application of FES therapy to the amputee population will directly expand the market size of electrical stimulators. The FES manufacturers could instantiate the rehabilitation protocol in their existing products to fulfil the application or develop a standalone product for amputees. The incorporation of the predictive amputee musculoskeletal model in the product design will lead to a reduced time to market and improved patient outcomes. The long-term FES application will also benefit the manufacturers of FES components such as electrodes, sensors and battery and add a broader socioeconomic impact.
Educational beneficiaries: the project will allow Dr Ding as a STEM (Science, Technology, Engineering and Maths) Ambassador to run activities in local schools focus on the biomechanics applications of STEM subjects. Also, she will disseminate impressive animations and case studies on musculoskeletal modelling and simulation in her lab website to attract a broad range of students to study biomechanics, making a wider academic impact.