It used to be that people who lost use of a limb because of neurological injury or illness had little hope of getting it back. But Stanford scientists have been testing a number of interventions that show just how resilient the human brain -- and body -- can be.
In a story for the latest issue of Stanford Medicine magazine, "The most mysterious organ: Unlocking the mysteries of the brain," I describe some restorative methods that have helped impaired individuals move again.
"We are at an inflection point where we are starting to give functions back to people," Michael Lim, MD, PhD, professor and chair of neurosurgery at Stanford Medicine, told me for my story.
Tapping one nerve to reinvigorate another
Lim's colleague, Thomas Wilson, MD, is among a handful of neurosurgeons using a technique known as nerve transfer surgery to help stroke patients regain use of an arm after injury. The procedure involves taking a functional nerve with a less critical role and stitching it to a damaged nerve. The functioning nerve then regenerates through the damaged nerve to gradually restore function.
Wilson says the technique could be applied to patients with spinal cord injuries and traumatic brain injuries, though there is much more to learn about how to achieve the best results and which patients could benefit.
"I think there are probably a lot more people we could help if more clinicians were aware of what we have to offer," he said.
Recovering after stroke
Neurosurgeon Gary Steinberg, MD, PhD, has been helping stroke patients regain some lost movement through a very different medium -- stem cells. Steinberg's approach involves injecting bone marrow-derived stem cells into the area of the brain impacted by stroke. The approach showed significant improvement in patients' ability to walk and move.
He participated in a multi-center study in individuals with traumatic brain injuries, some of whom showed improvements in their ability to walk and move their arms. Steinberg is now starting a study to better restore movement in stroke patients using a neural stem cell developed in his lab that he suspects has some advantages over the bone marrow-derived cells.
"We expect that if this strategy works, we will be extending it to other indications like traumatic brain injury, spinal cord injury and, hopefully, even neurodegenerative diseases like Parkinson's, ALS, or, ultimately, Alzheimer's, though that's quite a bit in the future," said Steinberg.
Deep brain stimulation
For patients with Parkinson's disease, Helen Bronte-Stewart, MD, is continually refining techniques for deep brain stimulation, in which clinicians implant an electrode in the brain to reorganize the abnormal signals that cause impaired movement. The device, regulated by a pulse generator in the patient's chest, delivers steady stimulation to the brain, helping control the tremors and gait problems associated with Parkinson's.
Bronte-Stewart has been accumulating data on the signaling patterns of the brain among patients with the implant. She is part of an international trial that aims to develop an algorithm that can automatically adjust the stimulation in response to what is happening in the brain in real time.
Illustration by Harry Campbell