Smart garments for painful swollen limbs

When Dr Massi Hesam was growing up in Iran, she and other family members spent hours massaging her aunt’s swollen limbs. 

Hesam’s aunt had lymphoedema – a painful and often disabling condition where the lymphatic system doesn’t work properly and fluid builds up, usually in someone’s arms or legs.

Some people are born with lymphoedema, like Hesam's aunt, but often it develops if the lymphatic system – the network that removes waste and fluid from tissues and pushes it into the bloodstream – is damaged, for example when lymph nodes are removed during cancer treatment. 

Almost 40 percent of breast cancer survivors develop lymphoedema and there could be up to 250 million people living with the condition worldwide.

There is no cure; treatment involves extensive massaging of the areas where fluid builds up – basically pushing it back into the right channels. That’s what Hesam and her family were doing with her aunt.

Later her aunt got a massage chair, Hesam says. “She was sitting on that almost all day – it was the only way to control her lymphoedema.”

But it was an inexact science. How much massage pressure was right, and in which direction? Where were the best places to apply pressure, and how long should the massage last?

“Massage chairs are not designed for this purpose; it’s not that efficient. I witnessed how hard it was for my auntie to control it,” Hesam says. “[When I became a researcher] it was always in the back of my head.”

Now working with the Auckland Bioengineering Institute (ABI) Biomimetics Lab at Waipapa Taumata Rau, the University of Auckland, Hesam is working to bring precise data and personalised treatment to the control of lymphoedema. 

“For my PhD, I designed a compression sensor to measure the external pressure that is applied to a surface. Now I'm using that to design variables where I would want to measure the external pressure on the body.”

Pressure from touch on the body surface is surprisingly subjective, Hesam says. Imagine a handshake with a stranger. One person might experience it as being at a good, normal level of pressure, whereas the other might feel it as bone-crushing or limp.

It’s the same with pressure applied with lymphoedema massage – it’s individual. 

These days, lymphoedema is increasingly treated with what’s called an ‘intermittent pneumatic compression’, or IPC device – a sort of cross between a compression sock you might wear on the plane, and an all-of-limb blood pressure cuff.

The device wraps around someone's arm or a leg and has chambers which inflate and deflate increasing the flow of blood and lymphatic fluid. Clinicians can dial up or down the squeezing from the cuff, but it’s still an inexact science.

Which is where Hesam’s sensors come in. Her team at the ABI has recently received $1 million through the Government’s Endeavour Smart Ideas fund to develop soft, skin-friendly sensor garments that will fit under an IPC pressure cuff and measure the level of squeezing being applied. 

“We’re working with a commercial partner – a New Zealand company named Medella Health,” Hesam says. Medella has developed an IPC device named Flowpresso used for lymphoedema. 

Imagine a pressure cuff wrapped right around someone’s lower leg. 

“So there is a nice assumption that the initial pressure inside the chamber is what the patients receive on their body, but that’s not correct.

“We did a lot of research and we discovered the pressure is not homogeneously distributed all over the limb, partly because human limbs don’t have a uniformly cylindrical shape.” 

The way a technician wraps the cuff also changes the pressure. “There’s an inconsistency between the pressure inside the cuff and what patients actually feel.”

Hesam’s goal is to develop garments fitted with rows of sensors, which offer real-time measurement of the pressure being applied by the cuff to an individual patient’s body, enabling clinicians to adjust the treatment setup more accurately. 

“The patient wears our smart garment over the area affected by oedema [swelling], and the intermittent pneumatic compression suit is wrapped over it. Clinicians adjust the treatment based on the real-time pressure data.”

Personalised medicine

Hesam’s long-term plan is to integrate artificial intelligence (AI) into the system. 

“In the second phase, we are going to fit the data to an AI algorithm to make everything automated and personalise the treatment,” she says.

Future versions will include sensors that also monitor swelling volume in real time, helping the AI model learn how each patient’s body responds to pressure.

As for the timing?

“If we want to be optimistic, I would say after a year we should have the hardware, and by the end of three years we can have the first pilot test.”

Hesam still thinks of her aunt managing her swollen limbs with a massage chair at home. “I want to be able to help her.”