Breakthrough alert! High-frequency spinal stimulation reduces spasms, enabling better mobility for spinal cord injury patients.

Electrical stimulation of the spinal cord is a potential method for regaining walking ability following spinal cord injury. However, for patients suffering from muscle spasms, stimulation procedures have a limited effect due to the unpredictable nature of involuntary muscle rigidity associated with spasticity. Muscle spasticity affects over 70% of spinal cord injury patients.

Researchers at EPFL, Università San Raffaele, and Scuola Sant’Anna have discovered a potential method for treating and reducing muscle spasticity in patients with incomplete spinal cord injury. It includes zapping the spinal cord with high-frequency electrical stimulation, which prevents aberrant muscular contractions.

This high-frequency treatment provides patients suffering from spasticity with previously unavailable rehabilitation programs, with excellent therapeutic outcomes. The findings were reported today in Science Translational Medicine (1).

High-Frequency Stimulation Combats Paralysis and Spurs Locomotion Recovery

“We discovered that high-frequency electrical stimulation of the spinal cord, combined with the usual continuous, low-frequency spinal stimulation, is effective during rehabilitation after spinal cord injury, overcoming muscular stiffness and spasms in paralyzed patients and effectively assisting the patients during locomotion,” says Silvestro Micera, professor at EPFL’s Neuro X Institute and Scuola Sant’Anna.

“This is a safe and effective surgical approach that provides a fresh viewpoint in the treatment of individuals with severe spinal cord injury. We intend to broaden the indications to include various clinical disorders that will be defined during the following month. Pietro Mortini, Head of the Neurosurgery and Stereotactic Radiosurgery Unit at IRCCS Ospedale San Raffaele (Milan) and full professor of Neurosurgery at the University Vita-Salute San Raffaele, expresses his gratitude to the patients who put their trust in us.

Electrical stimulation of the spinal cord is an indirect technique to access the motor neurons that control muscle movement. This is because sensory neurons on the back of the spinal cord connect with motor neurons.

High-Frequency Stimulation Helps Reduce Muscle Spasticity After Spinal Cord Injury

In muscle spasticity is associated with overreactive spinal sensory-motor pathways. In reality, the spinal cord is naturally overreactive to stimuli, which is beneficial because it allows for quick responses. Normally, the brain balances out the overreactivity by inhibiting the motor circuits. Spinal cord injury causes the patient to lose brain messages as well as inhibitory processes. The research team discovered that high-frequency spinal cord stimulation is an artificial and safe technique to reduce over-reactivity in individuals without causing discomfort.

During the clinical trial at San Raffaele Hospital, which was coordinated by Mortini and Micera, Simone Romeni, the study’s first author and a researcher at EPFL and Università San Raffaele, proposed implementing high-frequency stimulation, drawing inspiration from previous work on high-frequency kilohertz blocks of motor circuits by stimulating peripheral nerves.

“At this stage, we can only speculate that high-frequency stimulation acts as a kilohertz block that prevents muscle spasticity,” Micera adds.

“The clinical data from the two patients demonstrate the benefits of using high-frequency stimulation to reduce muscular stiffness and spasms in paralysis. More studies will be required to confirm the efficacy of this method,” Mortini says.

References:

1. Overcoming spasticity to help paraplegics walk again
   (DOI: 10.1126/scitranslmed.adp9607)

Source-Medindia