Why Recent Studies Are Questioning The Positive Effects Of Morton’s Neurectomy

“It’s been a while since I was up there on the summit,” I paused, “but I didn’t remember the air being so thin, and the temperature being so cold, and I have been to the summit, sad to say, many times.”

“How long has it been since your last climb?” Chamberlain asked. I said, “Can’t remember.”

“The reason you can’t remember is that when you are up there you are so clueless you don’t know squat, and that doesn’t account for the effect of the lack of oxygen and freezing temperatures your body is experiencing.”

Chamberlain was rotating a bottle of E.H. Taylor between his knurled fingers, still in its cardboard tube container, contemplating how he was going to frame the question, while at the same time admiring the vessel. Before he could muster his still-formulating question, I blurted out, “but I do recall something that I can’t really get a grasp on.” He nodded his head without uttering even a syllable. I acceded and started telling my story.

“OK, so I get up to the top of the mountain and look around. There is this giant field below, and I see all these people dressed in surgical scrubs, just pulling up these tangled roots out of the ground with absolute brute force. What they yanked out looked like yellow, stringy stuff, and they were hanging their uprootings on this rack. ‘Really weird stuff,’ I said to myself, and I heard all this banter among them about who’s was bigger.

“So, I asked some questions, and it turns out this field is known as Morton’s field, and these guys were up there just yanking the hell of these things! Pulling faster and harder right and left to see who could get the biggest one—I guess there was some prize or something they got for getting the biggest piece of ‘string cheese.’ Oh, there was this other group of people shouting at the pickers, and they had these giant syringe-looking things, and were shooting fluid out at them. Looked like water guns but turns out they were shooting out pure EtOH at them, and yelling ‘you get paid more for dousing them than pulling them out, you idiots!”

Chamberlain interrupted me. “You see this?” my good friend asked, pointing to the bottom of the cardboard tube. He was pointing to the bottom part of the label where it said “Bottled In Bond.” “Do you know what that means?”

Shaking my head ever so subtly from side to side, I admitted I didn’t. He proceeded to tell me: “You see, after the Civil War, Colonel Edmund Haynes Taylor Jr. started what we now know today as the bourbon industry. He was an innovator and made really good bourbon whiskey—with the highest and purest standards. But sadly, like in all things human, there are those who don’t do it the proper way or just don’t get it in full context. People take shortcuts, sometimes based in greed, sometimes in ignorance or who knows what. In this case it was probably greed. His ‘competitors’ made anything but a pure Kentucky whiskey product. Some went even so far to put tobacco, iodine and other non-sense crap into their elixir to the point where people were getting sick, some went blind, and some ended up dying.” Chamberlain handed me the tube. “That really pissed off the colonel.”

Chamberlain paused. I noticed that at the top of the tube, it had the inscription: “Let the label tell the truth.”

He went on. “So, E.H. gathered up a bunch of powerful folks—congressmen, senators, business tycoons—does his lobbying, and gets a law passed. The Bottled-in-Bond Act of 1897. That my friend was the first consumer protection act passed by the United States government to protect its citizens. 

“Wow, now I get it,” I responded through a politician-wide smile. “So, my good man, what you are telling me about the history of the bourbon whiskey industry is really a poignant allegory for what the podiatric and orthopedic profession is doing with Morton’s entrapment, still today in 2018, and that’s what I saw up there on Mt. Stupid.”¹

My barkeep buddy took the tube back from me. “Yes, it is. The ‘string cheese’ you saw them pulling out was symbolic of that poor little common plantar digital nerve being pulled out in a Morton’s neurectomy, and the folks squirting EtOH was symbolic of all those guys trying to kill that simply entrapped nerve.”

(We all know you can’t kill a peripheral nerve with an injection of anything that far out in the periphery, as the nucleus of the neuron resides either in the anterior horn of the spinal cord, or the dorsal root ganglion. Injection of EtOH is nothing more than an attempted injurious event inflicted upon an entrapped nerve. Therefore, patients, when you hear your foot “experts” tell you that they are going to “kill your nerve,” you now know that is nothing more than bovine feces, and you should probably find another true expert.)

Chamberlain then threw down some journal articles. “I took the liberty of grabbing some material from your library.”

I started to sift through them. Classics, I thought. “Where did this 85 percent success rate for Morton’s neurectomy number come from?” I asked him. “I see it referenced in about 10 of these peer-reviewed articles.”

Chamberlain broke his what appeared to be a pensive daydream. “If you trace some of these ‘statistics’ up the academic family tree, you will quickly see that many times, the proffered gospel number comes from a small sample size in a poorly constructed research design way back in the day. In fact, many times it is nothing more than a clinician’s retrospective review of a scant few patients.”   

“Right,” I confirmed. “Looking at most of these, there are very high success rate numbers, but when you look at failure rate, combined with the fact that even though a source may say he has an 80 percent success rate, what about the horrible downgrades that are true patient catastrophes?”

“Didn’t you tell me about the few years you worked at a tertiary peripheral nerve center?” Chamberlain asked.

“Yep, saw on average eight patients a month whose lives had been destroyed by a Morton’s neurectomy. One patient went on to a full disarticulation at the hip because of complex regional pain syndrome following the fetching of that little intermetatarsal nerve,” I said. Sifting some more, I found one that I considered to be the holy grail. “Womack, Richardson and colleagues: 120 patients, and a 40 percent poor result.”² “Wow!” 

The barkeep chimed in, “What about the alcohol?”

“Can you open the tube so that I can at least see the bottle?” I asked. “No, not this—the EtOH squirters. But yes, my good man, I will open up the tube,” he responded while starting to pull the top off. 

“Oh, right. Well it seems that, as with anything, there are usually some positive clinical effects with Morton’s neurectomy, but some of the recent studies really question those as well.³ Maybe we even have to question the histological effect now that Mazoch published his rat study.⁴ I do know that if you look at what has been published on alcohol injections, very few of the reported studies could even make a meta-analysis based on the quality level of research. Take this for example: Fannuci and colleagues in 2004 reported a 90 percent success rate at 10 months.⁵ Then a real study, Level II, done by Gerdezi and his cohorts, published in 2013, with a five-year follow-up, showed a whopping 29 percent success rate after alcohol injections.”⁶ Chamberlain laughed loudly with a baritone echo. “Vegas odds makers could not make a spread that wide: 90 percent to 29 percent.”

“Chamberlain, open that damn bottle. All this talk about alcohol makes me want drink it rather than talk about injecting the damn stuff into or around an unharmed nerve—what a terrible waste of a good substance.” I watched closely, almost like it was in slow motion thinking about how the Colonel must have felt with all those “contemporaries” bastardizing a process to cut corners and make money. “I wonder how many sclerosing injections would be done if there was no reimbursement for them? Interesting—right?”

“What sent you up to the summit again?” I waited a second to respond as it is difficult to come out and admit your own stupidity. “Thought I could help a patient who I knew had central sensitization. Didn’t work out so well.”

Well, I hope I tweaked some prefrontal cortices, maybe irritated a few, and woke up many. If you want to dive into a great case study, join me on my most recent Vlog: “Failed Morton’s Neurectomy and Why?” at https://youtu.be/0NVz2sE8osc .

References

1. Barrett S. Climbing Mt. Stupid: Examining the Dunning–Kruger effect in lower extremity peripheral nerve surgery. Podiatry Today DPM Blog. Available at https://www.podiatrytoday.com/blogged/climbing-mt-stupid-examining-dunning-kruger-effect-lower-extremity-peripheral-nerve-surgery . Published Sept. 5, 2018.

2. Womack JW, Richardson DR, Murphy GA, Richardson EG, Ishikawa SN. Long-term evaluation of interdigital neuroma treated by surgical excision. Foot Ankle Int. 2008; 29(6):574-577.

3. Santos D, Morrison G, Coda A. Sclerosing alcohol injections for the management of intermetatarsal neuromas: A systematic review. Foot (Edinb). 2017; 35:36-47.

4. Mazoch MJ, Cheema GA, Suva LJ, Thomas RL. Effects of alcohol injection in rat sciatic nerve as a model for Morton's neuroma treatment. Foot Ankle Int. 2014; 35(11):1187-1191.

5. Fanucci E, Masala S, Fabiano S, Perugia D, Squillaci E, Varrucciu V, Simonetti G. Treatment of intermetatarsal Morton's neuroma with alcohol injection under US guide: 10-month follow-up. Eur Radiol. 2004; 14(3):514-518.

6. Gurdezi S, White T, Ramesh P. Alcohol injection for Morton's neuroma: a five-year follow-up. Foot Ankle Int. 2013; 34(8):1064-1067.