We are coming to the close of the year. At this time, many individuals choose to reflect and look toward the future. There are emerging technologies that may improve spinal cord function. It is not to say you should not be content with your current situation. People reading this are doing so because they are thriving even if they are hopeful for improvement. Not everyone is seeking changes. Too many ‘hypes’ about upcoming research can be disappointing. However, it is important to know what is on the horizon so you can be prepared and make thoughtful decisions.
One of the biggest leaps is electrical stimulation which improves spinal cord function for some individuals. This is the use of the placement of electrodes on the skin that transmit electrical signals to the nerves and muscles. This therapy can be used for exercise, and function. In some instances, the nerve is directly stimulated. In other situations, one muscle or muscle group is stimulated. Typically, messages are sent to and from the brain, controlling body movement and sensation. In a situation where the message is blocked from an injury to the brain or not able to pass from an injury to the spinal cord, external stimulation can provide input to nerves below the injury and allow messages to pass more easily through damaged nerves. Remember, your body still works. It is just not getting a message from the brain. Motor or movement research studies are the largest in number and are most requested by consumers.
One of the biggest findings using surface or skin electrodes has been in the adjustment of placement of the electrodes. Whereas electrodes have been traditionally (and still are) placed directly over the target muscle and nerve, at the University of Washington, an electrode was placed directly on the back of the neck over the spine. This allows more nerves to be activated in the arm, hand, and fingers. The response is very impressive. Even more interesting is that there is some ‘hang over’ inability even after the device has been turned off. This technique has been used in individuals specifically with tetraplegia. However, it is just a matter of time before it will be tried with individuals with other neurological issues. If you are interested in this ongoing research from Dr. Moritz’s lab, the most recent publication with six participants can be found here: https://pubmed.ncbi.nlm.nih.gov/33400652/
This approach is currently being evaluated by a company called Onward (https://www.onwd.com/) in a larger clinical trial that has just completed enrollment. Onward will be evaluating the findings and, if warranted, hopes to have the stimulation device available to people with spinal cord injury in 2023.
External neuromodulation using electrical stimulation is also being used for other functional activities. Stationary biking was one of the first applications. This treatment assists with the reduction of spasticity, blood clots, and the difficulty of achieving cardiovascular workouts, along with other benefits. Patterned movement such as the repetition of biking has been noted since the polio epidemic in the 1940s. At that time, individuals would go to spas that promoted repetition that was done manually for hours. The bike does not require individuals to move body parts in tandem but accomplishes the same type of repetitive movement. The frustration has been in obtaining the equipment, which, once learned, can be achieved at home. Prices are dropping, so hopefully, this will become more widely available.
Currently and rapidly developing is neuromodulation ‘sleeves,’ which are stocking for your arm or a glove for your hand that contains electrodes. A battery pack is attached. These are configured to lead to functional movement. These devices are not for exercise but to improve function. Of course, function leads to activity in your muscles and nerves. Because of technology advancements (telephone batteries and 3D printing), the costs are projected to be within a reasonable range. Stay tuned for more devices in the development pipeline.
One interesting finding in external electrical stimulation is that sensory function can be improved when motor stimulation occurs. This outcome was achieved by Christopher Reeve when he participated in functional electrical stimulation. His sensory function improved. This enabled him to be able to know if he needed a pressure release or to feel the touch of another.
The harnessing of Central Pattern Generators in the brainstem and spinal cord has been capitalized in movement therapies from the electrical stimulation noted above but also in weight-supported walking and aquatic therapy. Central Pattern Generators are networks of neurons that, when activated, produce redundant and repetitive movement, including chewing, breathing, bowel function, urination, ejaculation, and locomotion. Your body is programmed to perform these activities. The brain starts and stops them, but the central pattern generator keeps things going until the brain says stop. It is like your body is on autopilot. Many movement therapies have capitalized on the Central Pattern Generator.
Exoskeletons are also rapidly advancing. These are mechanical structures that are worn on the outside of the body, which provides support and movement. They were first developed for the automotive industry to allow an individual to have more strength in moving heavy machinery. They were then adapted to provide functional movement such as walking to individuals with paralysis. There are several of these devices on the market. They are heavy and expensive. Some require the use of a standby person for assistance and safety. These devices, which are currently bulky, are being studied to be crafted into a supportive ‘skin’ type of construction. The research in exoskeletons is advancing rapidly.