Leg amputees wear commercial prosthetic devices that do not give any sensory information about the interaction of the device with the ground or its movement.
Amputees, relying on a very limited and uncomfortable haptic information from the stump-socket interaction, face grave impairments: risk of falls, decreased mobility, perception of the prosthesis as an extraneous body (low embodiment) and increased cognitive burden during walking with consequent psychological distress and device abandonments.
Because of these shortcomings, the majority of amputees remain wheelchair bound, immobile, or only partially integrated in the activities of daily life. Costs wasted on an unused prosthetic limb along with a sedentary lifestyle are associated with long-term medical problems (e.g. obesity, diabetes, cardiovascular diseases) and lifetime medical expenses.
In the US, these costs exceed €424k per person over his/her lifetime. For Europe, those costs will likely amount to at least 1/2 to 2/3 of the US costs (i.e. €250k – €330k). The mean 6-month direct medical costs of falls for hospitalized adults with transfemoral is about €23k. The mean costs for adults admitted to the emergency department is was about €16k.
There are some startups that are developing devices that can restore sensory feedback from the prosthesis, but they require a surgery for the patients. Not all the patients are eligible or willing to go through a surgery to use a sensory feedback restoration device.
We propose MYLEG, a unique device that restores sensory information about the prosthesis touch and movement through non-invasive electrical stimulation of the remaining skin of the patient. MYLEG does not need a surgery to be used and can be added to the currently available commercial prostheses. MYLEG is constituted by a sensorized insole that is added to the prosthesis, an external controller that transduces this information for a stimulating system constituted by portable stimulator and electrodes embedded in a portable belt. The optimal placement of the electrodes on the skin and the algorithms that control the stimulation make the elicited sensations very clear for the amputee, and thus the overall system easy to use.
The long-term vision of the MYLEG project is to improve mobility and prosthesis cognitive integration, by restoring sensory feedback, in people with leg amputation where they matter the most to them, during their daily life.
This will enable to blend the borders between everyday life and functional prosthetic use, with a threefold purpose:
- support independence in daily life through continuous sensory feedback
- enhance prosthesis acceptance and integration by enabling meaningful use in multiple settings
- reduce the economic burden on patients, healthcare systems and insurances caused by the disability (e.g. falls)