Why Every Patient with Peripheral Neuropathy Needs Custom-Made Orthotics
ORTHOTICS
Gregony Cofano
DC, DIBCN
Eight percent of the population in the United States has some form of peripheral neuropathy1. That’s 40 million Americans who are experiencing symptoms that can include tingling, pins and needles, burning, electric shocks, loss of balance, weakness, and autonomic symptoms in their feet2. One reason this number is steadily rising is because of the ever-increasing diagnosis of diabetes; up to 60% of diabetics can eventually develop neuropathic symptoms3.
Neuropathic symptomatology does not always present with pain, but can start as motor weakness, sensory alterations, autonomic or trophic symptoms, or a combination of these nerve fiber deficits. Many patients may initially experience a gradual decline of balance, loss of reflexes, loss of movement in the feet, or stiffness and a loss of feeling. These symptoms are referred to as “negative” signs, and they may be unperceivable to the patient early in the neuropathy continuum.
As peripheral neuropathy progresses and nerve fibers are further damaged, patients will develop “positive” signs that may include burning, freezing, pins and needles, tingling, stabbing, and sharp electrical shocks of pain. There is absolutely nothing positive about those painful sensations, and unfortunately, the mechanism for these painful dysesthesias is not fully understood. It has been theorized that ectopic discharges at the receptor or regenerating nerve fibers may result in dysesthetic pain. Another area of interest that can explain the painful symptoms of neuropathy is at the posterior horn of the spinal cord and the loss of mechanoreceptor input and subsequent loss of inhibition of pain at laminae I through III of Rexed4.
Finally, the brain has been shown to undergo morphological changes in response to exposure to chronic pain. One study investigated the volumetric changes by magnetic resonance imaging of the brain and revealed volume loss at the primary somatosensory cortex along with the supramarginal gyrus, cingulate gyrus, and thalamic gray matter5. Several histopathological changes at the nerves can present singularly or in combination with each other in patients with peripheral neuropathy. Wallerian degeneration, segmental demyelination, and axonal degeneration are the most prevalent types of distal nerve injury when dealing with peripheral neuropathy. Wallerian degeneration can lead to destruction of both the myelin sheath and axon distal to the point of damage. The myelin covering is considered the most delicate aspect of the nerve tissue, and when subjected to a disease state, results in segmental demyelination, which spares the axon. Axonal degeneration more commonly affects the distal aspect of the nerve and progresses up the limbs, commonly seen with metabolic conditions causing polyneuropathy. There are almost too many causes of peripheral neuropathy to list, but, as mentioned, earlier diseases, such as diabetes mellitus, autoimmune disorders, side effects from medications, toxic exposures, infections, and hereditary diseases can all be implicated6 7.
"Simply stated, peripheral neuropathy is a disease of the nerves that often presents in the feet."
Considering the sheer volume of patients who have peripheral neuropathy, what are you doing to treat the variety of symptoms and comorbidities they present with? One readily available treatment intervention that you can easily prescribe is custommade orthotics. Simply stated, peripheral neuropathy is a disease of the nerves that often presents in the feet. Damage to the nerves in the lower extremities can affect the function and tone of the muscles and lead to deformities of the feet8. Remember that there are peripheral neuropathy patients who do not complain of pain, and if you don’t ask about it, they may not tell you anything about their feet. Orthotics assist with better balance, reduce fatigue, and effectively treat pain conditions of the feet and spine9. Supporting the three arches with a functional orthotic provides the necessary correction of arch collapse and deformity changes that can progress if left unattended in your patients with peripheral neuropathy.
References:
1. Hovaguimian A, Gibbons CH. Diagnosis and treatment of pain in small-fiber neuropathy. Curr Pain Headache Rep. 2011 Jun;15(3):193-200.
2. Watson JC, Dy ck PJ. Peripheral Neurop athy: A Practical Approach to Diagnosis and Symptom Management. Mayo Clin Proc. 2015 Jul;90(7):940-51.
3. Abhijeet A. Adgaonkar, Dr. Anant A. Dawange, Dr. Shalaka A. Adgaonkar, Dr. V.G.Kale, Dr. Pravin P. Shekokar. A Study of Clinical Profile of Peripheral Neuropathy in Diabetes Mellitus. Sch. J. App. Med. Sci., 2014;2(4C):1347-1350.
4. Todd AJ. Neuronal circuitry for pain processing in the dorsal horn. Nat Rev Neurosci. 2010 Dec;ll(12):823-36.
5. Selvarajah D, Wilkinson ID, Maxwell M, Davies J, Sankar A, Boland E, Gandhi R, Tracey I, Tesfaye S. Magnetic resonance neuroimaging study of brain structural differences in diabetic peripheral neuropathy. Diabetes Care. 2014 Jun;37(6):1681-8.
6. Azhary H, Farooq MU, Bhanushali M, Majid A, Kassab MY. Peripheral neuropathy: differential diagnosis and management. Am Fam Physician. 2010 Apr 1 ;81 (7): 887-92.
7. Fevine, T, Small Fiber Neuropathy: Disease Classification Beyond Pain and Burning. J CentNerv SystDis. 2018 Apr 18; 10
8. Bariteau JT, Tenenbaum S, Rabinovich A, Brodsky JW. Charcot arthropathy of the foot and ankle in patients with idiopathic neuropathy. Foot Ankle Int. 2014 Oct;3 5(10): 996-1001.
9. Williams AE, Hill FA, Nester CJ. Foot orthoses for the management of low back pain: a qualitative approach capturing the patient’s perspective. J Foot Ankle Res. 2013 May 7;6:17.
Gregory Cofano, DC, DIBCN, is a board-certified chiropractic neurologist and former assistant professor at Palmer College of Chiropractic. He has authored several articles in journal publications concerning nenrotoxic medications causing neuropathy and other neurological conditions of the central and peripheral nervous system. Currently, Dr. Cofano practices conservative neuropathy treatments in Seattle, Washington.
