Imagine waking up one day, unable to move half your body. This is the stark reality for stroke survivors like Don Lewis, who, at 55, experienced a life-altering stroke while sleeping. His story isn’t just about paralysis; it’s about the hidden struggles that often go unnoticed—like proprioception, the body’s ability to sense movement and position. But here’s where it gets controversial: what if the key to better stroke recovery lies in addressing these overlooked sensory deficits? And this is the part most people miss: proprioception could be the missing link in personalized stroke rehabilitation.
Don’s journey began when his neighbor noticed his truck hadn’t moved for two days, prompting a welfare check. Paralyzed on his left side, he spent two months in the hospital, where he learned an aneurysm had caused his stroke. Through grueling physical therapy, he regained use of his left leg, but his arm remains paralyzed. ‘I feel pain if I bump it, but I can’t control it,’ he shares. Since then, Don, a cancer survivor, has endured two more strokes. Now, he’s collaborating with University of Delaware researchers to shed light on proprioception—a challenge often overshadowed by motor recovery.
Jennifer Semrau, an associate professor of kinesiology and applied physiology, simplifies proprioception for her students: ‘Close your eyes and touch your nose. If you can’t, your proprioception might be impaired.’ In a groundbreaking study published in Neurorehabilitation and Neural Repair, Semrau and doctoral candidate Joanna Hoh introduced a robotic testing method that identifies sensory losses without requiring patients to move their affected limb. This innovation could revolutionize clinical assessments, making them more accessible and precise.
In the lab, Don wears a KINARM robotic exoskeleton that tracks his upper limb movement. One test, the single-arm measurement, moves his affected arm robotically while he responds with his unaffected arm if he senses the movement. ‘We’re pinpointing the minimum movement someone can detect,’ Semrau explains. While the average person can feel movements as small as half a centimeter, post-stroke individuals vary widely. Some can’t detect a 10-centimeter shift—a difference that could mean accidentally touching a hot stove or a knife.
Here’s the controversial part: proprioceptive deficits are often mistaken for motor deficits because they’re so intertwined. ‘It’s hard to tell if the issue is feeling the arm or moving it,’ Semrau notes. Her lab’s research aims to disentangle these complexities, offering hope for tailored therapies. Pain and touch, for instance, operate on different nerve systems, so someone with proprioceptive loss might still feel pain but struggle with coordination. ‘Every stroke survivor’s impairments are unique,’ Semrau emphasizes, ‘requiring personalized treatment.’
Joanna Hoh, an occupational therapist, was inspired to pursue her doctorate after realizing the sensory system’s role in stroke recovery is often overlooked. Her dissertation explores how sensory issues impact daily activities. ‘Clinicians focus on motor function, but sensory recovery is equally critical,’ she says. Research shows that without sensory recovery, full functional recovery is unlikely—yet only 1% of clinicians assess proprioception in stroke patients.
Here’s a thought-provoking question: If proprioception is so crucial, why isn’t it a standard part of stroke assessments? Semrau and Hoh argue that clinicians and researchers must prioritize sensory testing to develop personalized treatments. ‘Understanding the motor-sensory connection is key to better therapies,’ Semrau adds.
Don’s story and this research highlight a pressing need: to bring proprioception into the spotlight of stroke rehabilitation. What do you think? Is enough being done to address these hidden deficits? Share your thoughts in the comments—let’s spark a conversation that could change how we approach stroke recovery.
