My mom’s friend Kevin from work always had new jokes and kept a few small toys in the bag on the side of his wheelchair for me and my siblings when we saw him. Kevin had been a paraplegic since he was 15 when he severed some nerves along his spinal cord. During Kevin’s life, there was no way to repair this, and eventually he died of health complications because of his injury. The other day, my mom sent me an email about a Washington Post article about this exact type of surgery, telling me she had only wished Kevin could’ve gotten.
The surgery was the first successful transplant of nose cells to the spine. Sounds crazy, but here’s how it worked: In the nose, everyone has olfactory ensheathing cells (OECs) that help constantly renew nerve fibers in the nose. Nerve fibers are integral to the sense of smell, but are constantly worn out—so OECs have to regenerate new ones. And regeneration is incredibly rare in the nervous system. In the past, disconnected spinal nerve cells couldn’t find each other and connect. OECs, Dr. Raisman first reasoned in 1969, could be the bridge.
Two years ago Professor Geoff Raisman and Dr. Pawel Tabakow, the lead neurosurgeon on the procedure, teamed up to repair the spinal nerve damage of 40-year old Darek Fidyka. Today, Darek can walk with a brace and, with physical therapy he’s been recovering from a surgery once thought impossible.
Here’s the equivocation: this was one surgery and one success story. Even the success of Darek’s surgery really won’t be fully determined for years as researchers and doctors monitor his progress. As much as I wanted to gush over this with my mom, I wasn’t convinced yet that this was the panacea she and everyone else had always wished for Kevin. So I looked into it some more, and here’s what I found.
As it turns out, the OECs are not the only nerve cells that can regenerate. In the spine itself are Schwann cells, which act as a protective shield around spinal nerve cells and can help regenerate damaged ones. Problem is, this study says, Schwann cells aren’t as good at it as OECs, which explains why another Raisman study said that the probability for recovery from severed spinal nerve cells increased from 20% to 80% when using OECs. I looked more into Dr. Raisman’s past research, and it seems that he and his colleagues have been on the right track. They developed an idea and a potential procedure with OECs, and then first tested it many times in animal trials on rats with success.
When it came time to talk about human trials, the first concern was safety. If OECs were transplanted in the spine, would it be safe or could there be complications. So in their first human trial, they tried the concept in a modified way with a lower dose for the three males they tested. What initially bothered me about this experiment was that the OECs didn’t seem to improve the spinal nerve cells in these men. But that wasn’t the point, researchers explained. That single blind controlled 2005 experiment wasn’t the same as the procedure Darek Fidyka got and wasn’t necessary aiming to cure these men, but instead to see if it was safe—which it was. Darek Fidyka’s surgery was the first successful trial of this OEC procedure. It’s important to note that the procedure worked on an injury that was essentially a clean break. There is no evidence to suggest it could work on more complicated injuries. Still, it’s impressive. Hoping to be more impressive, they want to do ten more trial procedures to test its reliability. We know from class that the more varied studies done on a procedure or hypothesis, the more likely the positive results are not false positives. If those 10 more were to have similar results, the probability that the results could be due to chance and not OECs would be so small that the procedure could actually become the new standard of care. Maybe those next tests will show the procedure works or that it has flaws or that it has flaws but still works. We don’t know yet because we haven’t seen that part of the movie yet.
The take home message though is that while there’s no certainty that this procedure is the answer to so many people’s problems, it’s on the right track to gaining that near certainty. If it does, it could be one of the biggest surgical and medical discoveries ever.