The human movement in biomedical engineering
The need
About , including those who have had limbs amputated due to complications from diabetes. Appropriate assistive technologies and therapies should be available, but there can be a gap between what people need and what engineers create.
The solution
Biomedical engineering students are being offered the opportunity to co-design assistive technology with people with a disability. This gives them a better understanding of the biomechanics’ application. Patient-specific digital models are also being developed so clinicians can choose the therapies and equipment that best suit an individual.
Biomedical engineering sits at the intersection of biology and technology. For Associate Professor Lauren Kark, investigating the human-machine interface is endlessly fascinating.
“It's really interesting to bring those two together. You have one system – engineering – that’s quite defined, and the human side that's undefined. And seeing how they marry is very, very, very interesting,” says Lauren, who oversees the academic program of the ʹڲƱ School of Biomedical Engineering.
“I think that's why biomechanics of human movement is so exciting; we’re trying to apply mathematical equations to a system that really defies or resists that at all points.”
Lauren sees human movement as a rapidly expanding research space. Improvements in cameras and software, and their decreased cost, mean that huge, specialist laboratories are no longer required for gathering data.
“It’s made it much more affordable and accessible to a lot of people. We can do a lot more gait [walking] analyses now than we ever could before.”
Increased computational power and the use of artificial intelligence are the other big developments. She points to the work of her colleague Dr Luca Modenese, who in minutes can develop a digital model of an individual’s neuro-musculoskeletal system using data from an MRI or CT scan.
It doesn't matter how fancy the prosthesis itself is, if it's not comfortable to wear, people aren't going to wear it.
Some orthopaedic surgeons are already using this patient-specific ‘digital twin’ to plan procedures before touching the patient.
“It's gone from, you know, science fiction, to something that almost could be integrated as part of the clinical management programs of patients,” says Lauren.
Smoothing the human-machine interface
Lauren trained as a mechanical engineer and started her professional life in an orthopaedics company designing hip replacements. After returning to ʹڲƱ to work on her PhD on amputee biomechanics, she noticed some engineers were focused more on the prosthetic device than on how a person would use it.
“They were placing the emphasis on making the components as technically amazing as possible and sort of neglecting the human-machine interface. I became increasingly interested in how the prostheses actually attaches to the human, because it doesn't matter how fancy the prosthesis itself is, if it's not comfortable to wear, people aren't going to wear it,” she explains.
In Australia, there are about , with about , according to the most recent analysis available. More broadly, about , with musculoskeletal issues such as arthritis or a bad back the most common.
Creating a prosthetic socket for a person is part science, part art. For example, fluid retention in the residual limb may change during the day depending on a person’s activity. This can compromise the fit of the prosthesis, alter the weight distribution, and lead to pain for the user.
“If there's a weakness in the chain, that's where it's going to happen – the human-machine interface. And it's so hard to get that right,” says Lauren.
One company, called , has pioneered 3D-printing of patient-specific sockets. A person’s residual limb can be scanned – whether they’re in Germany, Australia, Syria or Afghanistan – and that data can be sent to a 3D-printer to produce an appropriate socket.
It excites Lauren because it removes a bottleneck in prosthetic fitting and means donated prosthetics can be more easily adapted for people in developing countries.
Keeping the human in biomedical engineering
Lauren tries to emphasise the human aspect of bioengineering for her students. A few years ago, she set up the – now a pillar in ʹڲƱ’s – where students co-design and develop an assistive technology with a real client with a disability.
Past projects have included customised rowing prostheses, modified workshop tools for people with quadriplegia, walking frames with sensors to increase independence of older people with low vision, and squeeze gyms for children with autism.
The goal is for students to gain a better understanding of the biomechanics’ application and become more familiar with disability issues.
“Students who choose biomedical engineering are really driven by the opportunity for impact,” Lauren observes. “It's really about making a tangible difference to someone’s quality of life.”
And for staff and students at ʹڲƱ’s Assistive Technology Hub, the opportunities to do that are endless.