All of the focus for neuromodulation related to rehabilitation and recovery has been on the lower limb. Until now the upper limbs have not gotten attention. Not any longer. UCLA and the labs of basic scientist Reggie Edgerton and neurosurgeon Daniel Lu got a $6 million, five-year grant to study possible therapies for restoring hand function in tetraplegics.
To be sure, hand function deserves greater concern and emphasis. I have heard the argument that recovery of hand function is indeed a more pressing goal for research than walking. No doubt, it would be of great benefit to people with limited hand function to be able to transfer, feed themselves, and perform all sorts of daily living activities without help.
From a UCLA press release:
"Spinal-cord injury typically strikes people in the prime of their lives, with nearly half between ages 16 and 30," said Lu, an assistant professor of neurosurgery at the David Geffen School of Medicine at UCLA and a clinician at the UCLA Spine Center. "Currently there are no effective treatments for spinal-cord injury, and the resulting paralysis has been viewed as permanent. We are exploring ways to change that."
"Recovering the ability to use one's hands is a top priority for people with cervical spinal-cord injury," said Lu. "We aim to restore patients' independence by returning their ability to type on a keyboard, open doors and transfer themselves between their bed and wheelchair."
I popped over to UCLA a few days ago to get the story from Edgerton
, who as readers of these posts know, has been supported over the years by the Reeve Foundation to establish that the lower spinal cord, when fed with the right sensory cues, is able to direct movement and patterns of activity, without input from the brain. In advance of a published report in the medical literature, four human subjects
with implanted epidural stimulators on their lumbar spinal cords have reported significant recovery (a peer-reviewed publication is coming in April; this will allow the science community, and the general public, to better understand how the research was done and what the effect really was.)
“Our hypothesis with the upper extremity,” said Edgerton, “is that the cervical spinal cord probably will respond to interventions similar to what we have established in the lower spinal cord. Now there are reasons why that may not be true, but there are also reasons we should be able to show it is true.”
Experiments in five humans have already taken place. The data have not been published but will be very soon. Here’s what the ever-cautious Edgerton had to say: “We are very encouraged. We saw more than we expected, and more than we had hoped for. Our preliminary data suggest that the cervical spinal cord can be neuromodulated or electrically [epidurally] stimulated, similar to what has been seen in the lower spinal cord. Our results were better than we expected; we saw improvement in function in including hand grip strength but also the ability to control that movement.”
Edgerton is restricted by research protocol to say no more, but watch for a major paper on the first five humans in the hand function trial – it will make big waves.
Edgerton continues to work on epidural stim. A limitation to the work has been outdated technology in the stim devices. So, tired of waiting for industry to come up with a device that really addresses spinal cord circuitry, he and colleagues have started a company, Neurorecovery Technologies, to make such a device. Prototypes are coming along, including a totally new and very promising non-invasive stimulator. “The existing companies, their enthusiasm [for making a new unit for spinal cord stimulation] was unimpressive,” said Edgerton. “It was clear to us that we needed to have our own company.”
Regarding the hand function experiments: nothing has been cleared through the institutional review process, but it is likely human trials on upper extremity stimulation are not far off. Edgerton said he hoped a trial could begin in a year; 16 patients have already been identified.
The protocol, he suggested, might outfit each participant first with the noninvasive stimulator, then move on to a drug. Certain serotonergic agonists, already approved to treat depression, have shown some promise in animal studies. Thirdly, the patients might be set up with an implanted stimulator.
Beyond working on hand function, Edgerton hopes to see spinal cord stimulation work in improving bladder function and respiratory health, and not just in people with spinal cord injury. He mentioned the possibilities for stroke and Parkinson’s.