Combating Back Pain

Cal Poly team develops innovative spinal tape that monitors unsafe movements and raises posture awareness

by Emily Slater

Two Cal Poly engineering faculty members have teamed up on a research project that is eliciting excitement because it addresses the universal human experience of low back pain.

“Everyone can relate to back pain,” said biomedical engineering lecturer Britta Berg-Johansen, who added that up to 80% of the population will face one of the world’s biggest health problems at some point in their lives.

After years spent studying the human spine, Berg-Johansen believes that increasing awareness about the movements that lead to low back pain could be the key to prevention.

Berg-Johansen has teamed up with structural engineering Assistant Professor Long Wang to create a spinal tape that senses bending and twisting, alerting users through an app when they are displaying bad posture or holding a position for too long.

“We want to use sensors to prevent injury on the spine,” Wang explained.

The long strip of athletic tape is attached vertically to the center of the lower back, with tiny sensors made from flexible, sensitive materials affixed to the tape to measure movement.

The pair is pursuing a patent for their spinal tape with the dream of bringing the invention to the commercial market.

“We are in a back pain epidemic,” said Berg-Johansen, “and this product could help a lot of people.”

Joining Forces

Wang and Berg-Johansen met soon after they began teaching at Cal Poly in 2020 and formed a dynamic partnership.

“I knew we would make a good team,” Berg-Johansen said.

With her background in spine biomechanics, Wang’s knowledge of nanomaterials and a shared interest in wearable technology, the pair held a brainstorming session and landed on the idea for spinal tape.

They set out to create a flexible device for the lower back to contrast the rigid apparatuses on the market that attach to the upper back to aid those working in deskbased jobs.

Osos, joined the team in the summer of 2022 after Berg-Johansen enlisted him to code and design a new circuit board for the device.

Overcoming Barriers

While interviewing dozens of farmworkers and farm managers, Britta Berg-Johansen and Long Wang learned that undocumented workers may be afraid to report back pain or injury for fear of immigration action or being taken off the workforce.

One idea that came out of the CSU Innovation Corps program was to market spinal tape to the fitness and wearable technology industries on the premise that a device would be donated to a farmworker for every purchase made.

They could also collaborate with public health agencies, BergJohansen said.

The professors were selected to join the California State University Innovation Corps and received guidance in commercializing a medical device, completing a patent search to find out if an invention is new or novel compared to existing technology and identifying consumers.

Initially, they pinpointed farmworkers as their target market but after conducting over 50 interviews decided their device could not only help those at high risk for back injury but anyone interested in preventive health care and wearable motion tracking.

“This product will be generalizable for everyone,” Berg-Johansen said.

Engineering the Device

A biomedical engineering senior project team developed the first prototype during the 2021-22 academic year. The following year, a master’s student worked on the second prototype, connecting circuitry and creating a system to collect data.

Last summer, a $30,000 grant from the Department of Health and Human Services funded a group of biomedical, computer, materials and mechanical engineering students to create the third prototype.

“I love working on such an interdisciplinary team,” Berg-Johansen said. “It’s a really fun project and there’s never a dull day.”

Computer engineering student Aaron Rosen, of nearby Los

Earlier prototypes were bulky and couldn’t easily be worn, so Rosen used much smaller and thinner electronics that can be attached to the spine tape or a belt clip.

The challenge is to get consistent readings from the device, Rosen said.

Progress is measured in the Human Motion Biomechanics Laboratory where participants wear the spinal tape while twisting, bending and stretching. The cameras that line the room record motion data, which is compared to the data from the tape sensors for accuracy.

“The goal is that data from the cameras and the tape line up,” said Berg-Johansen who added they haven’t achieved sufficient alignment yet.

Both Rosen and Berg-Johansen hope to see a high level of accuracy by the end of the academic year, when Rosen will graduate.

As Rosen continues to adjust coding for the sensors, Wang is experimenting with different formulations of nanomaterials in his lab to increase the sensitivity of the spinal tape.

“The sensor’s response still needs to be improved,” Wang said. “The progress is promising but we still need to improve the design.”

Next Steps

Team members are applying the improvements made on the third prototype to a fourth model, which could be the final iteration.

“We are getting closer on the technology side,” said Berg-Johansen, who hopes to secure more grant funding and an industrial partnership.

They will design the aesthetics of the device, decide if users will need a tool to attach the tape on their own and develop the app. They also must consider how to detach the electrical component for reuse upon disposal of the tape after a day of wearing.

“I speculate a lot of people would use this,” said Rosen, who sees himself wearing the device while gardening to ensure good posture. ■