"앉아만 있던 그가 다시 걷기 시작했다" VIDEO: Paraplegic patients walk again with spinal cord implants

Paraplegic patients walk again with spinal cord implants

ABC Health & Wellbeing

By Jo Khan

Three patients with severe spinal cord injuries are walking again, thanks to a wireless implant which delivers electrical stimulation to the spinal cord.

Key points:

The patients are able to walk thanks to precisely timed electrical pulses from an implanted stimulator

The targeted stimulation technique works by reconnecting communication pathways between the legs and the brain

A new research centre at UTS will allow Australian trials using the treatment to begin in the next few years

Paraplegic patients walk again with spinal cord implants - Health - ABC News 

"앉아만 있던 그가 다시 걷기 시작했다" 스위스 연구진 경막외 전기자극 치료법 개발  하반신 마비 남성 3명 1주만에 걸어    만성 신경 손상으로 고통 받던 하반신 마비 환자 3명이 새로운 전기자극 치료를 받은 뒤 단기간에 걸음보조기의 도움만 받은 채 걷는 수준까지 회복됐다. 기존에도 전기자극을 이용한 치료 기술이 더러 연구됐지만, 치료 속도가 느리고 전기자극이 끝나면 효과가 사라지는 단점이 있었다. 사지 마비 환자 치료에 전환점이 될 것으로 기대를 모으고 있다. 그레고르 쿠틴 스위스 로잔연방공대 교수와 조슬린 블로흐 보도대병원 교수 공동연구팀은 척수를 다쳐 최소 4년 이상 하반신 전부 또는 일부를 움직이지 못하던 남성 환자 세 명을 자신들이 개발한 새로운 신경 전기 자극 장치를 이용한 치료 기술로 회복시키는 데 성공해 그 결과를 31일 ‘네이처’와 ‘네이처 신경과학’ 각각 발표했다. 이들이 개발한 기술은 피부 아래에 전극을 심어 척수를 직접 건드리지 않고 전기 자극을 전달하는 경막외 전기자극(EES) 치료법의 일종이다. 쿠틴 교수팀은 수년 동안 동물을 이용해 신경의 움직임을 연구해, 뇌가 척수를 통해 다리를 움직이도록 신호를 보내는 과정을 실시간으로 정교하게 밝혀냈다. 이를 바탕으로 인체 척수에 전극을 삽입해 걷는 데 필요한 다리 근육을 정확히 골라 필요한 때 선별적으로 자극하는 새로운 치료 기술을 완성했다. 왼쪽 다리를 들어 앞으로 내뻗기 위해서는 허리 근육을 이완시켜야 하고, 다시 오른 다리를 뒤로 뻗어 몸을 앞으로 향하게 하려면 무릎 쪽 근육을 수축시켜야 한다. 이 과정을 각각의 신경에 순차적으로 전기자극을 가해 가능하게 한 것이다. 이는 기존에 시도되던 전기 자극 치료가 대부분 신경에 전기를 지속적으로 흘려 주던 것을 개선한 것이다. 쿠틴 교수는 “기존의 치료는 다리에서 척수를 거쳐 뇌로 전달되던 감각 등의 정보를 중간에 차단시켜 오히려 자력으로 걷는 능력을 떨어뜨리곤 했다”며 “우리는 전기 자극을 ‘스위스시계처럼 정확하게' 필요한 때 필요한 위치에 가한 결과 환자가 의도한 대로 움직이게 할 수 있었다”고 말했다.   실험에 참여한 환자 세 명이 걸음보조도구와 전기자극기만을 착용한 채 걷는 모습. - 사진 제공 네이처 연구팀은 전기를 가하는 시점과 위치를 정밀하게 제어해 세 명의 남성 환자에게 실험했다. 그 결과 환자는 빠른 속도로 다리를 움직이는 능력과 걷는 능력을 회복했다. 실험에 응한 세 명의 환자 모두 일주일 만에 몸을 기댄 상태에서 걸음을 옮길 수 있게 됐다. 5개월 뒤에는 근육을 스스로 움직여 발을 뻗는 거리와 들어올리는 높이를 통제할 수 있게 됐다   재활을 마친 뒤, 이들은 상체를 위로 들어 지탱해 주는 보조 도구나 유모차 형태의 걸음보조기에 스티모만 착용한 채 1㎞이상을 걷는 데 성공했다. 자전거도 탔다. 심지어 스티모를 꺼도 운동 신경이 일부 활성화됐다. 쿠틴 교수는 “정확한 전기 자극 치료가 신경세포 사이의 연결을 새롭게 만드는 효과도 있다는 뜻”이라고 말했다. 이번 연구로 사지 마비 환자의 치료와 재활 연구가 새로운 국면에 맞을 것으로 보인다. 지난 9월 말에도 미국 메이요대 의료진 등이 시판용 전기자극기를 이용해 한 20대 하반신 마비 환자를 걷게 하는 치료법을 성공시켜 뉴잉글랜드의학저널(NEJM)에 발표한 적이 있지만, 이 때는 15~85주의 긴 시간 재활과 치료가 필요했다. 하지만 이번 기술과 결합하면 더욱 효과 좋은 치료기술이 탄생할 가능성도 있다. 체트 모리츠 미국 워싱턴대 재활의학과 교수는 '네이처'에 기고한 해설 글에서 " 최근 의료기술들과 이번 연구 결과는 마비환자 치료의 전환점이 될 것"이라고 말했다. 이번 연구의 임상시험을 담당한 블로흐 교수는 “일주일 만에 환자가 걷기 시작했을 때 우리의 연구가 제대로 가고 있다는 확신이 들었다”고 말했다. 두 연구자들은 GTX 메디컬이라는 스타트업을 공동으로 세워서 마비 환자를 위한 맞춤형 신경 치료 기술을 개발할 계획이다.  윤신영 기자 ashilla@donga.co 동아사이언스

edited by kcontents

In two studies published today in the journals Nature and Nature Neuroscience, scientists have shown that targeted electrical stimulation of the spinal cord, combined with intense physical rehabilitation, enabled these paraplegic patients to recover their leg movement and eventually start walking again.

A team based at the Swiss Federal Institute of Technology (EPFL) surgically implanted spinal cord stimulators in the patients, with the aim of activating the spinal cord via an electrical pulse.

Lead researcher Gregoire Courtine said the targeted stimulation technique works by reconnecting communication pathways between the legs and the brain, which have been damaged by a spinal injury.

"We have observed neurological recovery in our three participants which has never been seen before," Professor Courtine said.

                                  Patient Sebastian Tobler attempts to walk while supported by a harness

                                  Improvements for the patients, including Sebastian, only came after a lot of 

                                  hard work — as well as the electrical stimulation treatment. (Supplied: Jean-

                                  Baptiste Mignardot)

Swiss precision

The three patients had electrodes surgically implanted at the back of their spinal cords, which were connected to a wireless electrical pulse generator.

Using precisely timed electrical pulses, the scientists stimulated the region of the spinal cord that the brain was also trying to activate when each patient tried to walk.

"We stimulated the spinal cord the same way the brain would do naturally. This synergy enabled the paralysed person to make a hip flexion and swing movement," Professor Courtine said.

"Within a few days, people who had been paralysed for a few years could make stepping movements."

During the trial the patients were supported by a harness, allowing them to move safely. (Supplied: Jean-Baptiste 

Mignardot)

The resulting movement also encouraged the growth of new sensory pathways in the brain and spinal cord — restoring connections damaged by the injury.

"The targeted stimulation is key to trigger the growth of the new nerve connections, because when two neurons fire together, they established new connections," Professor Courtine said.

The research represents cutting-edge progress in the field of spinal cord injuries, according to Sylvia Gustin, neuroscientist and psychologist at Neuroscience Research Australia (NeuRA) and the University of New South Wales, who was not involved in the study.

"It definitely gives us a lot of hope, which is extremely important," Dr Gustin said.

"This opens a completely novel avenue for spinal cord injury rehabilitation."

Learning to walk again

After several months of intense physical therapy, the patients could start walking hands-free.

Professor Courtine has been working in this area for 15 years and said the results were "amazing".

"It was a very emotional moment the first time they walked," he said.

The most surprising moment occurred, he added, when the implants were switched back off again: some of the patients' recovered abilities persisted, even in the absence of those helpful electrical pulses.

"It was the first time I've seen the recovery of voluntary movement without stimulation, which is true neurological recovery," Professor Courtine said.

The team also developed a voice-activated watch app that allowed the patients to self-moderate their electrical stimulation and walk with a wheeled walking frame — or even cycle on a modified tricycle — outside the laboratory.

Patient Sebastian Tobler was in a mountain-biking accident in 2013 that left him with complete paralysis in both legs, but he now uses an adapted tricycle. (Supplied: Jean-Baptiste Mignardot)

"I remember the first time we went outside by the lake here in Switzerland, and one of our participants who was bound to a wheelchair for seven years just walked … for about 500 meters." Professor Courtine said.

"That's a moment you will never forget in your life."

'No longer false hope'

Commenting on the research, neuroscientist Bryce Vissel from the University of Technology Sydney said the research was a major step forward for people with spinal cord injuries.

"I think we are now in a stage where it's no longer false hope — this is real hope," Professor Vissel said.

"What we don't know is how it's going to work in every single patient, but the principle is now established beyond reasonable doubt and it's going to get better."

Dr Gustin, meanwhile, cautioned the new treatment was not a miracle cure — and the patients in this first trial all had incomplete spinal cord injuries, which means they had some surviving neural pathways between the brain and spinal cord.

"They have enhanced the surviving signal so that, in some way, the brain can talk to the legs again," she explained.

"This is absolutely a promising step for spinal cord injury research, but we might need to target it a bit differently for people with complete spinal cord injuries."

Sebastian Tobler's spinal cord injury was so severe that doctors were not able to offer him a walking rehabilitation program, so he built himself a recumbent hand tricycle — which has since had electrical stimulation technology added.

Professor Courtine said Mr Tobler did not experience the same level of recovery as the other two patients, because of the severity and chronic nature of his injury.

"The later you start the treatment, the longer it takes to see improvements," Professor Courtine said.

"We have sufficient evidence to use these treatments in the early stage after spinal cord injury, when the potential for growth of new nerve connections is higher, and the neuromuscular system has not yet undergone the atrophy."

However Professor Courtine warned the new treatment was not a "magic pill" for people with spinal cord injuries.

"This is intense training, and without [patients having] the will to recover it would not work," he said.

"We provide the tools to help the brain help itself, and then the rest is in the hands of our patients."

Experimental set up at EPFL with scientists looking at computers and patient in support harness on a treadmill.

After first trialling the treatment in rats and apes, the team of scientists worked for months with the patients to train them to walk. (Supplied: Swiss Federal Institute of Technology (EPFL))

Australia on track for new trials

The University of Technology Sydney will have a research centre capable of administering this treatment in trials within the next year, according to Professor Vissel.

"Some of the people who come into the experiments here in Australia will be seeing recovery that they never thought was possible," he said.

"We believe it can be rolled out in a very real way within the next three to five years, which is phenomenal for Australia."

No spinal cord injury is the same, and treating complete injuries — where there is no connection left between the brain and the spinal cord — will require a combination of techniques, Dr Gustin said.

"We're developing a virtual reality walking intervention to restore touch perception in people with some types of spinal injury," she said.

"If we can stimulate the central nervous system and peripheral nervous system at the same time, the additive effects could restart touch perception and movement in some people."

https://www.abc.net.au/news/health/2018-11-01/neurotechnology-restores-walking-spinal-cord-injury/10446050

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