Bionics and prosthetics have continued to interweave across the last few decades and will continue at a rapid rate into the future with new ideas and concepts being developed all the time.
What Are Prosthetics?
So… what are Prosthetics (or prosthesis)? Prosthetics are an artificial body part used to replace function of a missing arm or leg.
Prosthetic limbs have come a long way in the past decades. Some 25 years ago the only types of knees clients with an above knee amputation could use were mechanical knees which worked off physics and the movement of weight around a knee axis and relied on the user’s strength and control to provide safety during walking. These days bionic systems have developed with knees capable of ‘reading’ the situation and responding in real time to provide safety for the user.
Similarly upper limb prosthetics were only available in body powered varieties which meant the user had to perform specific movements of their shoulders to cause excursion of a cable system connected to a harness and result in movement of the terminal device or joints in their upper limb prosthesis to achieve function. Now there is a wide range of upper limb technology which is getting closer and closer to mimicking more natural upper limb function.
As time has gone by and prosthetics have developed it is evident that bionics is a critical field that continues to expand the many options available to our clients to better meet their mobility, safety and functional needs.
What Are Bionics?
What are Bionics? Bionics can be defined as the replacement or enhancement of organs or other body parts by mechanical versions.
Currently there are bionic above knee systems available which use state-of-the-art sensor systems to mimic a natural walking pattern and provide an extremely high level of safety and function for the user.
These knees have sensors which detect movement at up to 100 times per second and then respond by controlling resistance in their control mechanisms to provide the appropriate safety or mobility as required at each stage of the walking cycle. These types of knees can be controlled through hydraulic control or smart fluids such as magnetorheological fluid and these control mechanisms change the way the knee reacts in each situation; the sensors act like a ‘brain’ in the knee and control the knee function to keep the user safe.
Upper limb bionic technology has developed to include systems capable of reading muscle activity and muscle activity patterns and controlling upper limb components off this muscle function.
They can include sockets which have electrodes which are essentially specialised sensors built into the walls and positioned over functioning muscle bellies in the residual limb. These tiny ‘sensors’ detect a change in muscle activity so when the user wants to perform a movement they can squeeze the muscle and this activity is detected by the sensor and this is converted into movement of the terminal device (hand or hook) on the prosthetic limb.
There are even systems emerging which allow the user to simply think about performing a movement as they did pre-amputation and the sequence of muscle activation which occurs allows movement of multiple upper limb joints at a single time which is exciting and ground breaking technology in the field of upper limb prosthetics.
If you have any questions or would like to know more about this, please speak to your prosthetist.