China's brain-spine interface technology helps paralyzed patients walk again

A team of Chinese scientists and surgeons successfully conducted a minimally invasive "brain-spine interface" (BSI) surgery, restoring​ a paralyzed patient's ability to stand and walk within 24 hours post-surgery.

The surgery, fourth of its kind for clinical proof of concept, was conducted at Shanghai's Zhongshan Hospital, but it was the world's first to enable an individual with a total paraplegia – an impairment in motor or sensory function of the lower extremities – to be able to stand and walk through BSI technology, the hospital announced on Tuesday.

The BSI technology was jointly developed by Zhongshan Hospital and Fudan University's Institute of Science and Technology for Brain-Inspired Intelligence. Led by Professors Wang Xin and Ding Jing from Zhongshan Hospital as well as Jia Fumin from Fudan University, the trial evaluates the safety and efficacy of epidural electrical stimulation (EES) in restoring motor function for patients with spinal cord injuries.

When the spinal cord is injured, the connection between the brain and spinal neurons is disrupted, leading to partial or complete paralysis. 

To address this, Professor Jia's team pioneered a groundbreaking "three-in-one" BSI technology. Through minimally invasive surgery, they created a "neural bridge" between the brain and the spinal cord, which collects and decodes brain signals and delivers targeted electrical stimulation to specific nerve roots. This innovative approach allows paralyzed patients to regain control of their limbs, marking a transformative leap in spinal injury treatment.

During the minimally invasive surgery, two electrode chips, each about one millimeter in diameter, were implanted into the brain's motor cortex. The entire procedure, including both brain and spinal cord interventions, was completed in just four hours. Within 24 hours post-surgery and with the assistance of artificial intelligence, the patient regained leg movement, according to Fudan University.

The most significant challenge of this BSI technology lies in the limited number of electrodes available for implantation in the human body and the ability to decode human movement intentions in real time. 

"If a patient wants to lift their leg, but the algorithm fails to decode the intention or delays by even a few seconds, the patient could fall," Jia explained. After nearly three years of relentless effort, the team finally achieved a breakthrough in algorithm design, enabling real-time decoding of brain movement intentions.

From January to February this year, the team had completed three clinical proof-of-concept surgeries. Patients with severe spinal cord injuries regained the ability to control their legs and walk within two weeks.

"The treatment outcomes for these paralyzed patients met or even exceeded our expectations, preliminarily demonstrating the feasibility of the next-generation brain-spine interface solution. The completion of four surgeries across two hospitals also proves that this technology is replicable and scalable. This is not just a technological victory but the beginning of a new life for paralyzed patients," said Jia.

The team will continue to optimize and iterate the technology, aiming to restore walking ability for more spinal injury patients and bring hope to millions of patients and their families worldwide.