Our research will transform how upper arm bionic prosthetic function works, transforming the user experience to such a level that when a person picks up a cup or opens a door they can do so as naturally as an able-bodied person.
The need for bionic prosthetics
- Around 5,500 adults and children in the UK are living with an upper limb amputation or have congenital upper limb deficiency and hundreds more amputation procedures take place every year.
- According to the MOD, in Afghanistan 240 British servicemen suffered amputations after being wounded between 2007 and 2013
- Since that time many more serving and ex-military personnel have lost limbs through complications, or in other conflicts and accidents within the armed forces.
- Upper limb amputation is functionally more disabling than lower limb amputation because of the vast number of fine motor skills undertaken by the hand and arm.
- Limb-loss is extremely traumatic for patients and their families. It can impact on a patient’s mental as well as physical health and affect their emotional wellbeing, independence, mobility and financial situation.
Current prosthetic solutions
There are a variety of bionic limbs available; however, they all have a number of drawbacks that affect both wearability and functionality for the user.
- The functionality of even high-end upper limb bionic prosthetics is still extremely poor – they can be unreliable, impractical and difficult to use.
- Bionic limbs are crudely attached onto the amputation stump with sockets, straps and harnesses. Depending on their mobility, it can be extremely difficult for the patient to put on a bionic limb by themselves
- The sockets, harnesses as well as the bionic arm socket can all cause painful chafing, which can lead to infection
- Once fitted, the bionic limbs are difficult to manage, deliver very little practical benefit
- Currently electrodes and wires are placed on the skin to transmit signals however, these are prone to fall off making the arm unusable.
Bionic prosthetics – a future with functionality
Rather than develop new bionic prosthetics, we are focusing on developing pioneering technology that will enable existing and future upper limb bionic prosthetics to work as effectively as the human arm.
Bionic prosthetics without wires
Current bionic prosthetics are operated using wires, which are placed on to the skin and transmit signals from the arm stump enabling the arm and hand to move. However, these are only able to detect a limited number of clear signals so the prosthetic does not always function in the way desired, if at all. The wires also can restrict natural movement and often fall off as the wearer moves or due to sweat, making the bionic arm impractical to use.
Studies in the US and UK indicate that more than 66% of amputees find usability and comfort such an issue that most only wear their prosthesis for up to two hours a day and a significant number give up using it altogether.
Jon-Allan Butterworth Paralympic champion says;”I have access to the very best bionic limbs and frankly after a few hours its like walking around with an over sized pair of shoes on with the laces undone”.
Eradicating wires for good
We are working closely with UCL to develop a micro electronic device that will be implanted under the skin on the amputation stump. This device will allow signals to be sent directly from the brain through the patient’s muscles directly to the bionic prosthetic arm and back again.
The end result will be a prosthetic arm that works intuitively just like a human arm and is practical and affordable.
Project completion 2018
RAFT bionic prosthetics Research Scientists:
- Lilian Hook
RAFT bionic prosthetics Research Partner:
RAFT is collaborating with University College London (UCL) on this project.