Diabetic Neuropathy: Is Surgery An Option?
The surgical technique is beyond the scope of this article but involves the release of the common peroneal nerve at the neck of the fibula with release of the peroneal retinaculum in that region. The surgery also entails release of the deep peroneal nerve on the dorsum of the foot, including the extensor retinaculum over the nerve and transection of the extensor hallucis brevis tendon over the dorsum of the first metatarsal. The third nerve release involves the tibial nerve and its branches, including the medial, lateral plantar and calcaneal branches. Finally, one would perform an internal microvascular neurolysis of any scarred or fibrotic nerves in order to decompress internal fascicular compression on the nerve bundles as deemed necessary.
It is not a very difficult process or surgery and the most difficult aspect is the tarsal tunnel region. There is also a rapid recovery process for the patient. One would emphasize no weightbearing or limited touchdown weightbearing for two to three weeks until removing the sutures. Patients may then progress to increased weightbearing, as tolerated, and physical therapy.
In terms of complications, one mostly sees superficial wound dehiscence, which clinicians can treat very easily with local wound care and antibiotic therapy. There may be some mild increase in tingling and pain at first as the nerve begins to hyperreact to decompression but this pain resolves over time.
Ensuring Appropriate Patient Selection
To put it simply, this surgery is not meant for every patient with diabetes. The results have shown that the success of the procedure is not age dependent and that, with proper patient selection, the procedure will help improve pain relief in most cases.
However, as I stated earlier, the initial problem was treatment of painful neuropathic legs. These patients cannot sleep at night, cannot walk well and often use multiple medications, including narcotics, to treat their pain. They are often young and would like to be more active.
As the results have been good in the painful cases, the pendulum on diabetic nerve entrapment is also swinging to the extreme and patients with no pain are being treated with decompression for sensation restoration. This is far more risky and often surgeons are dealing with a patient who has no true symptoms and is only worried about possible ulcer formation. Why not treat such a case with insoles, local foot care education and observation?
In most cases, including studies and results from Dr. Dellon, sensation restoration in a patient without pain is a 50-50 shot. In contrast, resolution of pain in cases of painful neuropathy is 80 percent successful when there is a positive Tinel’s sign of the nerve region. The results of sensation restoration on the average non-symptomatic patient with diabetes are not good enough for me to pursue.
That said, if there is a young patient with multiple previous ulcers, excellent circulation, a positive Tinel’s sign and no pain, I may discuss the surgical options and note that it may help prevent ulcer formation if the patient can feel pain.
However, my current protocol is far more selective. I reserve this procedure only for patients who have severe pain; no relief from pain with oral medications such as gabapentin or duloxetine HCl; excellent circulation; and multiple risk factors. In these cases, the results are far more predictable and the outcomes can change lives.
What really changed my mind about this procedure and the underlying philosophy behind diabetic neuropathy and sensation restoration is the fact that a large number of carpal tunnel and ulnar nerve transposition surgeries in the upper extremity are performed on patients with diabetes. Many of the hand surgeons I know at UCLA and in my community do not think twice about the idea of carpal tunnel surgery on a patient with diabetes, and often will state that carpal tunnel syndrome may be partly due to diabetes and its complications.