How The ‘Phoenix Sign’ Can Predict The Success Of Nerve Decompression

"It has been a very long time, my man," Chamberlain said as he pushed a gluten-free pint toward me.

"Yes, it has,” I quickly and shamefully responded with my eyes deliberately lowered, trying to avert his judgmental inspection of my facial affect.

His body language, evidenced by his tightly crossed arms and perfectly erect stature, indicated to me that he was aghast at actually having to serve a gluten-free beer. "Where in the hell have you been? I believe you Americans say something like ‘going AWOL’.”

I paused to allow myself to finish a sip of the horribly tasting gluten-free concoction (but perhaps the best mind-preserving beer manufactured to date). This also gave me a little time to fashion the response I thought he would want to hear.

“Well, it started with a trip to Pistoia and ended up with seeing the sign,” I told him. “What sign? Italy?” he asked.

“The Phoenix Sign,” I replied in a tone that conveyed that everyone should know about it except the most ignorant but I will get to that later. “And yes, Tuscany.” I loved holding him as an intellectual hostage occasionally.

Pulling his tie tighter and with more intensity than a functional MRI, he scanned me as if he really had to ascertain that it was me since it had been so long since we had danced the limbic tango together. (Look up limbic resonance if you want to know what the hell we are talking about here.)

Sputtering due to the vile taste of the beer, I pushed the pint back toward him and asked for something with tranquility for the palate. “How about a shot of that Eagle Rare 17-year-old, you have back there, since we are going to be talking about birds today.”

“Good taste you have, sir,” he affirmed as if assaying my gustatory microvilli.

“Cheers,” we bellowed simultaneously. The noise of clinging glasses resonated in the quiet bar.

“Well, the trip was long, long enough for you to change venues as well I see.” He put the expensive bottle carefully back on the shelf as if it were a rare artifact and turned back to face me. He said nothing. He just cleared his throat with that deep, guttural sound that said so much without saying a word. I got no answer about his new drinkery.

I began the explanation of my hiatus (call it more of a sabbatical) and knew I had him captivated when he circled around from back of the bar and sat down at the nearest table, motioning for me to join him. “Plant your arse, mate, and get on with the details.” 

“Ok, there were—still are, for that matter—many questions about what we see daily, but never really and profoundly make the connection, which could be more clinically beneficial for patients,” I said. “Frankly, I now have far more questions than answers than I had before the beginning of my quest,” I admitted.

“Why Pistoia?” he prompted.

“Well, I figured I would try to start the journey by finding the grave site of Civinini and go from there.” He gestured without speaking for me to go on. “I finally found it! There it was. It was almost hidden by a greenish, mossy-like patina yet the eroded engraving of the headstone clearly showed the dates: 9/20/1805–5/11/1884.”

“But why start with Civinini?” Chamberlain asked.

“Because that poor bastard has been intellectually kidnapped for 183 years now and I had to have a starting point.”

I shifted myself toward him, so close in fact I got a big huff of his citrusy cologne. “We have ‘Civinini’s canal,’ ‘Civinini’s ligament,’ ‘Civinini’s process,’ and even a foramen named after him. But no, the foot boys still have not given poor Filippo any credit and still call it a damn ‘neuroma’ for God’s sake.” I could feel the pressure rise in my already bulging and pulsatile neck veins. My English gentleman friend just watched me as I am sure the color on my face was changing into a crimson hue as I went on and on—until he finally interrupted me.

“Seems like the sabbatical did very little for your ability to contain your ‘Morton’s neuroma’ outrage,” he scolded.

I demurred. He was right. I still hadn’t let go of this historical injustice of medical nomenclature. “OK, you’re right,” I affirmed. “Please forgive me for the tangent.”

He pushed my drink closer to me, signaling me to take a pause and gather myself. “I know there is something good coming so get to the point,” Chamberlain advised. “Tell me about this Phoenix Sign. Did you see it there in the cemetery?”

“No, no,” I said, “but it was not far from there. I was out in this dilapidated small village, that was all helter-skelter, about 20 miles from town, when I first saw the sign,” I shrugged. “I must say that while I had the extreme displeasure of having to stay there for a short period of time, I learned something very cool.”

“And …” Chamberlain goaded. 

I went on to explain that one day while we were captive in this dreary locale, my nerve fellow and I had worked up this patient who had chronic pain after a bad inversion ankle sprain, but there was no ligamentous damage as proven by magnetic resonance imaging and physical examination. The patient was already developing a drop foot and had a very significant provocation sign of the common peroneal (fibular) nerve over the fibular neck. So I informed the patient I would provide a diagnostic block with just a miniscule amount of lidocaine under sonographic guidance, and see how the pain responded.

Chamberlain nodded. I could tell right now that I had the old boy’s frontal lobe in such a tight and firm grasp that I could have twisted his mind around like the wet, small branches of a bonsai tree during manicure time.

“So then, that’s when I first saw it! About four minutes after the block, the patient somehow manifested full 5/5 motor strength of the extensor hallucis longus and tibialis anterior whereas before the block, he barely had 2/5 strength. Oh, and by the way, all the pain was gone but not sensation.”

(The "Phoenix Sign" is the phenomenon when increased muscular strength in the extensors of the foot, specifically the extensor hallucis longus muscle, occurs following a sub-anesthetic dose of lidocaine 1% to the common peroneal (fibular) nerve. The Phoenix Sign is a positive predictor of a certain degree of success following nerve decompression surgery. Like the phoenix, the nerve appears to rise from the ashes. If you would like to see this with your own peepers, click on this site: https://youtu.be/CrPDp4fCDTI . I made it myself. It’s special, I promise.)

My voice almost went into falsetto as I could hardly contain my enthusiasm. Yep, I pulled out my smartphone and started pressing buttons. When the video started, I just let it play as the phone laid on the table. For nearly four minutes, nobody said anything and there was virtually no physical movement by him. I observed him carefully and noticed his pupils greatly dilate about halfway through. When it ended, I carefully slid the phone back into the breast pocket of my blazer.

“How can you explain that?” the erudite one asked. Was he truly perplexed for once in his life?

“I will try after you have had a little time to digest it,” I answered as I got up from the table and walked slowly toward the front door. Just as the door was about to shut, I shouted back to him. “If you can observe like Civinini, you will see ‘signs’ all the time.”

Filippo Civinini was the great Italian anatomist from Pistoia, who served as the chair for anatomy at the University of Pisa. While he has never received proper recognition for his anatomical observation in 1835 of Morton’s entrapment in the forefoot, he has had numerous other eponyms attributed to his large body of work. He only walked this planet for a short 39 years. He was born in 1805 and died in 1844. Some say it was Durlacher who really discovered Morton’s entrapment but that is erroneous as Durlacher described it in 1845, 10 years after Civinini published his anatomical observation.