There is much discussion about employing surgical decompression for diabetic peripheral neuropathy, both for pain and to prevent neuropathic foot ulcerations. I have 3 main concerns.

1. This treatment does not make sense, pathophysiologically. The pathophysiology has been well described and it does not include "swelling" of peripheral nerves. The double-crush theory is accepted, but why would all 3 major below the knee nerves suffer a double crush injury at the same time?

2. No objective modality (EMG/NCV) has been able to prove the usefulness of lower extremity nerve decompression. The PSSD is an instrument that hasn't been proven, is not accepted by neurologists, nor is accepted as a research modality due to operator dependency and the fact that it is still a "psychophysical" test like the SWMF or biothesiometer.

3. Why do all three peripheral nerves (common peroneal, deep peroneal, tibial) need to be released? If for pain, shouldn't this be dependent on pain symptoms? If for prevention of ulcers, why the deep peroneal? (Perhaps to prevent flip-flop associated ulcers?)

These are my thoughts. I'm interested to see the discussion that follows.

Unfortunately, those of us who have done a large number of decompressions have not published our results. Not all patients with nerve entrapments and coexisting diabetes, are candidates for nerve decompressions. Positive Tinel's signs over the deep peroneal(DP)nerve & posterior tibial(PT)nerve are good clinical indicators of entrapment or compression. This is also true over the sural nerve at the lateral calcaneal tubercle, the medial dorsal cutaneous nerve at the dorsomedial aspect of the 1st metatarsal head, and less commonally over the superficial peroneal branches over the dorsum as well as dorsolateral aspect of the foot. The value of PSSD testing is being able to measure the difference between the loss of two point and one point sensation. The inability to feel two point sensations at a measurable amount of pressure(gms/sq.cm.)is the first to be lost in a given distribution to an entraped nerve. After a certain period of time (this is extremely variable in our patient population)one point sensation to the distribution of the entraped nerve starts to be lost(indicative of axonal death) and the Tinel's signs deminish as well. The PSSD is very useful in quantifying the amount of axonal death which is invaluable as a predictor of the chances for successful decompressions. The diagnosis of an entraped nerve is still based upon clinical signs and symptoms. Decompression of an entraped nerve with a positive Tinel's sign and specific post operative care is 80% successful even in patients with coexisting diabetes.

I remember being skeptical whether nerve releases could address neuropathic pain or even temporarily restore epicritic sensation to the foot until Lee Dellon himself operated on 2 patients at our institution that had tested positive for nerve entrapment using the criteria set forth by the PSSD. Patients had longstanding diabetes with symptomatic peripheral neuropathy as well as a positive tinels and could not feel his fingers touching their toes. Nerve releases were performed and a lidocaine injection was only performed along the skin and not the released nerves for post operative pain management. Patients reports return of sensation immediately in the recovery room able to feel Dellons finger touching each of the digits even reporting the specific digit that were being palpated. Seems like a miracle, but at that point I was a believer. We perform nerve releases specifically on patients with recalcitrant symptomatic peripheral neuropathies unresponsive to pharmaceutical therapies ,albeit few as in our locality, neurologist do not generally believe surgical nerve releases as an accepted method of treating painful neuropathies.

I have heard heated debates at both national and local multispecialty conferences regarding whether neuropathy is a surgical versus medical problem. Neurologist criticize the lack statistical evidence supporting surgical releases despite longitudinal, some controlled multicenter and single institution trials that were performed giving some credibility that patient improvement is less of a surgeon-biased phenomenon. They specifically criticize the lack double blinded placebo controlled randomized trials which would be difficult to perform as I am certain both patients and IRB would frown on placing a sham incision site on patients as a control. Shy of being a turf battle, how will we find common ground with a research trial that would satisfy both parties.