In physical therapy, time is everything. Studies have shown that increased repetitions of exercises improve outcomes, which suggests more and longer therapy sessions. However, time costs money in the form of therapists, rehabilitation gym space, and time away from other activities. Therefore, any device which seeks to improve rehabilitation through higher repetitions must do so in the constraints of time requirements. Time is the enemy, but it is also an opportunity. Rehabilitation robotics are able to address many of the challenges to repetition with the allotted time, but care must be taken to not lose those benefits with setup costs. The timer on the therapy session doesn’t start when the patient starts walking, but when he or she enters the gym.
One of the most fundamental concepts is that walking in an exoskeleton can increase the number of steps that a patient can take during a session. The device does this by minimizing the need for therapist support (manually moving the leg, providing trunk support, etc) and by providing enough assistance to allow the patient to be successful in each rep. I see patients who had struggled to take 10 steps in parallel bars walk hundreds of steps in their first EksoNR session! They are upright, moving, retraining those neural pathways to execute a step, and are supported to keep their body in the proper alignment while minimizing strain on the therapist.
There is much more than walking that we must consider while designing a robotic exoskeleton around donning and doffing the device, programming it, and making clinical decisions that optimize outcomes. We as engineers cannot overlook these aspects that contribute to or detract from our product..
One summer internship, I was tasked with timing every step on the manufacturing floor to determine where time could be saved. While those I was observing didn’t appreciate the teenager with a stopwatch scrutinizing their every move, I learned a lot from this experience. I saw the importance of breaking down each part of the process to understand where time is used and I learned the importance of doing that in the real environment. So often, we speak to therapists and they say “Oh, it doesn’t take long to set up.” And that’s true when I know my settings and have tools in hand. But in the clinic, as you observe a session (stopwatch in hand), you see the seconds tick by as they search for a tool or as they have to re-check the sheet for a setting after being interrupted by a colleague asking about the next patient. By breaking down these time losses into small pieces, we can find solutions. Sometimes it is as easy as redesigning a form so that it is easy to glance at a setting or adding a hook for a tool. Other challenges may require more complex solutions, but the more we focus on solving these challenges, the more time that therapists can spend with upright and walking patients.