“Space Pants” help alleviate leg pain

Stephen Scott suffers from peripheral artery disease (PAD). Heat therapy using “space pants” developed by Purdue University researchers have enabled Scott to stand longer and walk longer distances.

He gets up in the early morning hours to make his coffee. He turns on the TV. He channels his inner-astronaut and puts on his space pants one leg at a time. He attaches the portable water pump to the space pants. He flips a switch and then settles into his recliner for 90 minutes of therapy.

The space pants and pump are two items being used in a clinical trial led by a Purdue University researcher who is exploring the use of non-surgical and in-home options to help people such as Scott manage peripheral artery disease (PAD).

Statistics from the American Heart Association show that PAD is increasing. More than 8.5 million people in the U.S. and more than 200 million people worldwide are affected by lower-extremity PAD, which is the narrowing of the peripheral arteries serving the legs. The most common symptoms of PAD include cramping, pain or tiredness in the leg or hip muscles while walking.

Bruno Roseguini, an assistant professor in Purdue’s Department of Health and Kinesiology, is studying whether leg heat therapy is beneficial for patients suffering from PAD. Roseguini also researches the use of heat therapy in athletic recovery. His findings indicate that leg heat therapy increases blood flow and accelerates recovery following muscle injury in young individuals. He is now testing that in older adults.

Roseguini’s study participants use water-circulating trousers – a special pair of tight-fitting pants that look like a wetsuit but with water tubes – that are used by astronauts to regulate their body temperature while in space. Participants put the pants on and then hook up the tubes to a small pump that sends warm water around the lower limbs.

The goal is to get people moving again with limited pain. While there is no cure, there are therapy, medication and surgery options for PAD. Increased physical activity, dietary changes and lifestyle modifications can help with symptom management. Frequent supervised use of a treadmill in a clinical setting is recognized as the preferred treatment for symptomatic PAD.

Heat therapy has been used in a variety of methods for back pain, muscle recovery and more. Roseguini said this type of treatment is different from compression therapies for knees, legs or trauma, which are traditionally used to prevent blood clots

“My goal is to find non-invasive therapies that can be used in a home setting to restore blood flow and help people move again,” Roseguini said. “Leg heat therapy can be done in the home setting and is practical for patients with multiple conditions and who cannot participate in standard exercise routines.”

A growing number of studies indicate that heat therapy improves the health of blood vessels and facilitates skeletal muscle recovery following injury.

“Heat therapy is a powerful tool for rehabilitation,” Roseguini said.

Roseguini’s other goal is to make the therapy mobile, which doesn’t exist – yet. When he started his clinical studies, the “portable” water pump was the size of a 1970s-era microwave. It is now the size of a single-serve coffee machine, but the individual is tethered to it and an electrical outlet. “I want the patients to be able to receive the therapy while walking and performing their daily living activities, such as going to the grocery store,” Roseguini said.

Currently, the heat therapy regimen calls for putting on the pants, waiting 30 minutes for the water to warm up to the proper temperature and then be hooked up to the pump for 90 minutes every day for eight weeks.

“It’s like putting your legs in a hot tub without getting wet,” Scott said. “It feels good.”

After retiring from a career in power plant maintenance, Scott made an appointment with his physician to discuss his leg pain. After the diagnosis, the physician gave him three options: Start walking more, have surgery or participate in Roseguini’s clinical trial.

“The biggest thing was I couldn’t stand for a very long amount of time, and my walking was limited,” Scott said.

Clinically speaking, Scott is not allowed to know what treatment options he has received. But after going through the trials, Scott said he can now stand for long periods of time and can walk longer distances.

Scott agrees with Roseguini’s results so far. “What matters is that they are working to find some help or relief, which can benefit someone else down the line.”

Roseguini’s health research aligns with Purdue’s Giant Leaps celebration, acknowledging the university’s global advancements made in “Health, Longevity and Quality of Life” as part of Purdue’s 150th anniversary. This is one of the four themes of the yearlong celebration’s Ideas Festival, designed to showcase Purdue as an intellectual center solving real-world issues. 

For his research on heat therapy, Roseguini has received funding from the American Heart Association, the National Institutes of Health and the Indiana Clinical and Translational Sciences Institute.