The Office of Naval Research (ONR) in the US is set to collaborate with Walter Reed National Military Medical Centre, the Naval Research Laboratory, and certain universities in the country to develop a smart artificial leg called Monitoring Osseointegrated Prostheses (MOIP).

MOIP will feature sensors that are specially designed to monitor walking gait, notify prosthetic wear and tear, and warn users of potential infection.

To avoid the pain and skin infections commonly observed with existing wooden leg prosthetics, MOIP will use an alternative titanium fixture that is surgically implanted into the thigh bone or femur.

Following bone growth at the connection point, a small metallic connector is left protruding from the remaining leg, allowing attachment of an accompanying artificial limb.

The artificial leg can also be detached at will and the same procedure is applicable for upper limbs.

ONR Warfighter Performance department programme officer Dr Liming Salvino said: “This new class of intelligent prostheses could potentially have a profound impact on warfighters with limb loss.

“MOIP not only can improve quality of life, but also usher in the next generation of prosthetic limbs.”

To detect, eradicate and prevent infection due to metal, MOIP will include electrochemical sense-and-respond approaches and smart skin technologies.

“This new class of intelligent prostheses could potentially have a profound impact on warfighters with limb loss.”

An amputee’s residual limb will be embedded with the bio-compatible sensor array, while additional sensors will be included in the osseointegrated prosthetic.

The array is designed for tracking changes in body temperature and pH balance, which are considered as indicators of infection.

The sensors will also monitor fusion and healing processes between the bone and prosthetic limb, as well as assess the prosthetic’s strength and changes to movement and walking gait.

The University of Michigan engineering professor Dr Jerome Lynch and his team have created a prototype of the MOIP sensor array using osseointegrated prosthetics and synthetic bone models that are manufactured at the university.