Low back pain is a leading cause of disability and one of the most common reasons for seeking medical treatment. In Europe, low back pain is number one in terms of years lived with disability – increasing by more than 50 % since 1990. There’s also an economic cost. For instance, after the common cold, low back pain is the leading cause of worker absenteeism, accounting for 15 % of all sick leave and hundreds of millions of lost workdays. Robotics is quickly emerging as a leading solution for mitigating the pain – and costs – associated with lower back injuries. Most available robotic assistive devices are exoskeletons worn by the patient. Although successful at augmenting leg and arm motion, these devices neglect the important role that the spinal cord plays in transferring load from the upper body and arms to the legs. To fill this gap, the EU-funded SPEXOR project is designing a revolutionary solution. “SPEXOR is an innovative spinal exoskeleton that not only prevents low back pain in able-bodied workers, but also supports those already suffering from low back pain who want to get back to work,” says Jan Babič, project coordinator and a researcher at the Jožef Stefan Institute in Slovenia.
A natural extension of the body
Similar to a brace, albeit a very high-tech one, SPEXOR is attached to the thighs, pelvis and back. A mechanical joint, located at the hip, and a bendable spinal mechanism take the load off the spine. The use of carbon fibre rods provides a supportive lift and removes the strain from the back. Springs located at thigh level offer a light push to the legs. Weighing just 6.3 kg, the system utilises integrated sensors to detect when a person wants to bend down. As a result, SPEXOR is automatically activated when needed and remains in a passive or ‘hibernated’ mode when not in use. “The beauty of this device is that it knows what you’re doing and, based on complex algorithms, can predict what you’ll do next,” explains Babič. “This ensures that SPEXOR is unobtrusive, essentially becoming a natural extension of the body.”
Teaching and preventing
According to Babič, SPEXOR aims to work as both a teaching tool and a preventative device. As to the former, the device buzzes whenever the user lifts something incorrectly. “This feature is essential to our ongoing study of how humans bend their backs,” he says. “This helps us correct poor body mechanics and improve how we teach proper ergonomics.” SPEXOR also plays an important role in preventing low back problems. It does this by taking over part of mechanical loading from the spine, thus reducing the risk of such injuries as vertebral endplate fractures. “Mastering proper mechanics and motions is the ideal method for making muscles stronger and preventing injury,” adds Babič. “Unfortunately, sometimes we can’t avoid performing detrimental tasks, which is where the external support that SPEXOR provides comes into play.” The research team has filed a patent for its exoskeleton technology. Ottobock, one of the consortium’s partners, launched Paexo Back, a marketable solution based on the knowledge gained during the SPEXOR project.
SPEXOR, exoskeleton, low back pain, disability, robotics