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This week, I wrote about an external stimulator that delivers electrical pulses to the spine to help improve hand and arm function in people who are paralyzed. This isn’t a cure. In many cases the gains were relatively modest. One participant said it increased his typing speed from 23 words a minute to 35. Another participant was newly able to use scissors with his right hand. A third used her left hand to release a seatbelt.

The study didn’t garner as much media attention as previous, much smaller studies that focused on helping people with paralysis walk. Tech that allows people to type slightly faster or put their hair in a ponytail unaided just doesn’t have the same allure. “The image of a paralyzed person getting up and walking is almost biblical,” Charles Liu, director of the Neurorestoration Center at the University of Southern California, once told a reporter.

For the people who have spinal cord injuries, however, incremental gains can have a huge impact on quality of life.

So today in The Checkup, let’s talk about this tech and who it serves.

In 2004, Kim Anderson-Erisman, a researcher at Case Western Reserve University, who also happens to be paralyzed, surveyed more than 600 people with spinal cord injuries. Wanting to better understand their priorities, she asked them to consider seven different functions—everything from hand and arm mobility to bowel and bladder function to sexual function. She asked respondents to rank these functions according to how big an impact recovery would have on their quality of life.

Walking was one of the functions, but it wasn’t the top priority for most people. Most quadriplegics put hand and arm function at the top of the list. For paraplegics, meanwhile, the top priority was sexual function. I interviewed Anderson-Erisman for a story I wrote in 2019 about research on implantable stimulators as a way to help people with spinal cord injuries walk. For many people, “not being able to walk is the easy part of spinal cord injury,” she told me. “[If] you don’t have enough upper-extremity strength or ability to take care of yourself independently, that’s a bigger problem than not being able to walk.”

One of the research groups I focused on was at the University of Louisville. When I visited in 2019, the team had recently made the news because two people with spinal cord injuries in one of their studies had regained the ability to walk, thanks to an implanted stimulator. “Experimental device helps paralyzed man walk the length of four football fields,” one headline had trumpeted.

But when I visited one of those participants, Jeff Marquis, in his condo in Louisville, I learned that walking was something he could only do in the lab. To walk he needed to hold onto parallel bars supported by other people and wear a harness to catch him if he fell. Even if he had extra help at home, there wasn’t enough room for the apparatus. Instead, he gets around his condo the same way he gets around outside his condo: in a wheelchair. Marquis does stand at home, but even that requires a bulky frame. And the standing he does is only for therapy. “I mostly just watch TV while I’m doing that,” he said.

That’s not to say the tech has been useless. The implant helped Marquis gain some balance, stamina, and trunk stability. “Trunk stability is kind of underrated in how much easier that makes every other activity I do,” he told me. “That’s the biggest thing that stays with me when I have [the stimulator] turned off.”

What’s exciting to me about this latest study is that the tech gave the participants skills they could use beyond the lab. And because the stimulator is external, it is likely to be more accessible and vastly cheaper. Yes, the newly enabled movements are small, but if you listen to the palpable excitement of one study participant as he demonstrates how he can move a small ball into a cup, you’ll appreciate that incremental gains are far from insignificant. That’s according to Melanie Reid, one of the participants in the latest trial, who spoke at a press conference last week. “There [are] no miracles in spinal injury, but tiny gains can be life-changing.”