-1.5 C
Niagara Falls
Thursday, March 30, 2023
Dr. Brown: Walking again, after paralysis, thanks to modern research
A photo of Dr. William Brown. Supplied

We take for granted our extraordinary ability to get about on two legs.

Whether walking, running, dancing, skiing or skating, we do it all, depending on our age, without much thought.

Bipedalism for species ancestral to ours, evolved more than three million years ago, evidence for which may be found in the bipedal tracks left behind in east Africa by Lucy’s species, australopithecus afarensis and closely related species variants. 

Tragically, some of us lose that ability in part or whole as the result of trauma involving the spine or, insidiously in later life, the result of degenerative disease affecting the vertebra and discs. Strokes, amyotrophic lateral sclerosis or multiple sclerosis can also rob us of this ability.

The result is weakness in the legs, especially in the hip flexor, knee flexor and the muscles that control our feet. Sometimes the arms and hands are also affected.

In some cases, patients can lose control over their bowel and bladder and in males, the ability to develop an erection. Along with those motor and autonomic changes, patients may lose sensation at and below the levels of lesions. 

Over the years, there have been many attempts to improve lost motor functions with medications to relieve spasticity (stiffness) in the affected muscles.

Physiotherapy can be helpful, especially in mild to moderate cases but for severe impairments of motor and sensory function, there’s little choice but to use assist devices such as canes and walkers early on, and wheelchairs in severe cases. 

That hasn’t stopped surgeons from trying to relieve mechanical compressions from discs and bone on the spinal cord – or in the extreme, cutting out the most severely damaged part of the spinal cord and suturing what’s left together.

Fortunately, the latter highly publicized option in the 1960s was stopped for lack of evidence that it helped.   

Recently, there has been a flurry of studies, some involving implanting a multielectrode on the surface of the brain’s neocortex to record the electrical activity associated with intended movements and linking that activity with external devices such as a computer and prostheses to restore lost motor functions.

Unfortunately, the benefits were small as patients were tethered to cumbersome equipment  for little gain in function. Those studies and closely related ones were “proof of concept studies” of little practical value to patients.  

Then in 2018, scientists from the Swiss Federal Institute of Technology reported another approach for restoring walking in paraplegic patients who sustained trauma.

They stimulated the area of the spinal cord affected by the trauma using an electrode implanted in the epidural space. Combined with an aggressive program of physiotherapy, it led to significant improvements in some patients.

For example, some people who were completely paralyzed in their legs beforehand regained the ability to stand and walk, albeit for short distances and with support.

Later studies by the same Swiss group and others, confirmed the effectiveness of electrical stimulation in restoring function in partially or completely paraplegic patients. 

Later studies in animals suggested the effect was mediated by interneurons – nerve cells interposed between the input sensory and output motor nerve cells in the spinal cord.  

But whatever the techniques for restoring function to paralyzed legs, the challenge is the same: to restore lost or badly impaired functions of the brain or spinal cord by some sort of electrical boost or corralling preserved signals in the brain to bridge lesions further downstream between the brain and muscles. 

Over recent years, I’ve highlighted several claims for methods designed to restore meaningful speech, movement in paralyzed muscles caused by ALS and other paralyzing diseases, and most recently, boosting memory in patients with dementia. 

The experiments and trials are always complex, involve a lot of technical support and staff, and much time and effort on the part of patients and staff for meagre (so far) benefits.

Even so, I believe it’s worth the effort given the severity of the disabilities in many cases and the steep learning curve for all concerned, to find out what works, what doesn’t and overcome major technical and engineering hurdles.

If I may use an analogy, we are very much in the Orville and Wilbur stage of flight – full of promise, but a very long way to go.

Dr. William Brown is a professor of neurology at McMaster University and co-founder of the InfoHealth series at the Niagara-on-the-Lake Public Library.  

Subscribe to our mailing list