What is a Peripheral Neuropathy?

Jul 29

A peripheral neuropathy is a disorder in which nerve fibers outside the spinal cord are injured or degenerating. This prevents them from functioning properly, leading to a wide range of symptoms and problems.

Peripheral neuropathies can manifest in many different ways and locations. They generally affect the hands, feet or face; they can also be seen in other areas such as the arms, legs, chest and back. Peripheral neuropathies can create pain, numbness, weakness, feelings of pins and needles, or other uncomfortable sensations (1).

What is the Peripheral Nervous System?

The brain, cerebellum, brainstem, and spinal cord make up the central nervous system (CNS). The peripheral nervous system (PNS) consists of all of the nerves that exist outside of the brain and spinal cord. It is made up of a wide variety of nerves that carry electrical impulses toward and away from the CNS.

What are the Different Types of Peripheral Nerves?

There are several different classes of peripheral nerves in your peripheral nervous system. The pattern of symptoms you experience will depend on the type and location of the nerve fibers that are affected.

Types of peripheral nerves include:

Sensory nerves: These conduct inputs from the body to the CNS. Information about the environment such as temperature, touch, pain, and body position are carried to the brain through sensory nerves.

There are several different classes of sensory receptors that respond to inputs such as touch, pressure, vibration, temperature, and pain from the skin. When stimulated, these receptors transmit sensation through sensory nerves to the spinal cord, brainstem, and brain. There are other classes of receptors in muscles and joints that give rise to proprioception, your brain’s unconscious awareness of body position and stresses on muscles and joints. These fire into the central nervous system through large, fast peripheral nerve fibers, whereas pain and temperature are transmitted with small, slow nerve fibers.

Motor nerves: these convey messages from the brain to muscles to control movement. These allow functions ranging from postural stability to voluntary movement of the hands and feet. These are very large, rapidly conducting nerve fibers. When they are injured, muscles may spontaneously twitch, become weak, and atrophy.

Autonomic nerves: these are thin, slowly conducting fibers that go from the spinal cord and brainstem to various organ systems in the body. They control and regulate unconscious vital functions such as blood pressure, heart rate, digestion, bowel and bladder control, and respiration (2).

What are the Different Types of Peripheral Neuropathy?

Neuropathies are classified according to their cause, location, and the number of nerves involved.

A mononeuropathy affects only a single peripheral nerve, usually from some form of traumatic or repetitive injury. People can have more than one type of nerve injury in multiple locations, resulting in multiple mononeuropathies.

A polyneuropathy is a condition that affects multiple peripheral nerves in more than one location.

There are over 100 known types of peripheral neuropathy. They each have their own unique clinical presentation and prognosis (3).

What are the Symptoms of Peripheral Neuropathy?

Peripheral neuropathy can produce a host of different symptoms that may range from numbness and weakness, all the way up to paralysis of a body part with a severe nerve injury. Neuropathies can produce severe pain from sensations that are normally painless, such as clothing on your body or the weight of bedsheets on your feet.

Depending on the cause, your symptoms may include:

The slow and progressive development of numbness, tingling or prickling sensations in your hands and feet, moving up into the arms and legs
Pain that can be burning, throbbing, or stabbing
A sensation that you are always wearing gloves or socks
Weakness of muscles resulting in fatigue during normal activities
Sensitivity to touch and pressure from clothing and walking that produces pain
Muscle twitching leading to muscle atrophy
Balance problems and difficulty with walking, often resulting in falls

Poor regulation of blood pressure, resulting in dizziness or light-headedness when going from sitting to standing
Difficulty regulating digestion, or poor control of bowel and bladder function
Intolerance to heat or cold
Profuse sweating, or loss of the ability to sweat (4).

What Causes Peripheral Neuropathy?

Peripheral neuropathy may be the consequence of traumatic injuries, where nerves are compressed, sheared, or lose their blood flow. They can result from metabolic problems such as diabetes. They may be the consequence of viral infections or autoimmune problems. They are occasionally the result of chemical insults such as exposure to toxins. There are also a number of genetic conditions that result in degenerative neuropathies.

Nerves can be injured and damaged from direct trauma, mechanical entrapment, or from the persistent compression seen in repetitive stress injuries such as Carpal Tunnel Syndrome. With compressive neuropathies and traumatic nerve injuries, the larger fibers are usually affected first, resulting in sensory and motor symptoms such as numbness, weakness, and tingling sensations. When severe, small fibers that carry pain and temperature signals can also be affected.

When a toxic or metabolic insult leads to nerve damage, the effects are usually seen in a specific class of nerve fibers that exist in more than one peripheral nerve. Most kinds of polyneuropathy usually affect both sides of the body symmetrically, and tend to start in the hands and feet. They will generally progress up the limbs toward the trunk until the factors causing the insult are properly addressed. Most people with neuropathy are suffering with some form of polyneuropathy.

There are many different kinds of genetic neuropathies, and they manifest in a multitude of different ways. While the course of these is often difficult to predict, in most cases the earlier in life they present the more likely they will become progressive and even disabling.

Peripheral neuropathy may be caused by:

Direct nerve injury. Traumas, such as from motor vehicle accidents, falls or sports injuries, can sever or damage peripheral nerves. Nerve pressure can result from having a cast or using crutches or repeating a motion such as typing many times (.

Autoimmune diseases. Conditions including chronic inflammatory demyelinating polyneuropathy, Guillain-Barre syndrome, lupus, rheumatoid arthritis, Sjogren's syndrome, and vasculitis (13)
Diabetes. The majority of people with poorly controlled diabetes will develop peripheral neuropathy at some point (14).
Infections. Bacterial and viral infections causing peripheral neuropathy include shingles, Lyme disease, Epstein-Barr virus, and hepatitis (15).
Genetic disorders. Hereditary polyneuropathies include Charcot-Marie-Tooth disease and several types of autonomic neuropathies (16).
Tumors. Benign and malignant growths can compress peripheral nerves depending on their location. Some cancers lead to paraneoplastic syndromes that cause the immune system to attack peripheral nerves (17).

Exposure to toxins. Toxic substances include industrial chemicals and heavy metals such as lead and mercury (18).
Chemotherapy and radiation treatment. Certain medications, especially those used to treat cancer (chemotherapy), can cause peripheral neuropathy (19).
Vitamin deficiencies. Deficiencies of vitamins such as B1, B6 and B12 can cause peripheral nerve degeneration. This is often the result of alcoholism. Excessive intake of B6 can produce toxicity that also degenerates peripheral nerves (20).

Other diseases. These include kidney disease, liver disease, connective tissue disorders and an underactive thyroid (hypothyroidism) (21).

In a number of cases, no cause can be identified (1).

How is Peripheral Neuropathy Diagnosed?

Peripheral neuropathy can be challenging to properly diagnose. Many neurological examination procedures can shed light on neuropathy, including tests of deep tendon reflexes, muscle strength, sensory perception, gait, balance, and coordination.

Laboratory tests may be required, including tests for vitamin and nutrient deficiencies. Electrodiagnostic testing may be necessary. These may include a nerve conduction velocity study (NCV), a test of the speed of transmission of nerves to evaluate for sites of compression, and electromyography (EMG), a test of the electrical activity in muscles (22). In other cases, a nerve biopsy may be needed to evaluate for other causes of peripheral nerve degeneration (23).

How is Peripheral Neuropathy Usually Treated?

Most peripheral neuropathy treatment focuses on addressing the condition that is provoking the nerve degeneration. In cases of compressive neuropathies from repetitive stress, an ergonomic evaluation and changes to posture may be necessary. When neuropathies are the result of diabetes, medication and dietary changes to control blood sugar can prevent the problem from progressing. In cases of autoimmunity, medication to control the immune system may be necessary (24).

Controlling a chronic condition may help manage your neuropathy, but it does not necessarily eliminate the problem. It is very common that symptoms persist long after the condition that created the neuropathy has been resolved, and may indeed become permanent.

How is the NeuroRescue Program Different?

We begin with a focus on correcting the underlying factors that have created your peripheral neuropathy. Depending on the condition, there are many different ways for us to use functional medicine to intervene in the process, ranging from labs to supplements to lifestyle changes.

For us, this is only the first step. We create your NeuroRescue program with the goal of resolving your symptoms and restoring your function, rather than merely stopping the progression. We use cutting edge diagnostic and therapeutic technologies to move you towards these goals.

One of the main things your brain does, and maybe even the primary thing, is help you determine where you are in the world. Your brain uses inputs from your inner ear to figure out where your head is in relation to gravity and how it is moving. It uses inputs from your muscles and joints to figure out where your body is in relation to your head and what your body is doing. It uses inputs from your eyes to figure out where your body is in relation to the visual environment.

Your brain needs to put all of that together to make sense of where the world is, and where you are in relation to the world. It needs to be able to localize you effectively in the environment, in order for you to be able to respond to the environment properly.

Your brain organizes all of this information in terms of maps. There is a vestibular map from the inner ear, a vascular map of your blood flow, a visual map of the world from your eyes, and several others. There is also a propriceptive map from muscles and joints, which is created by the inputs from your peripheral nerves. Your brain needs these maps to be saying largely the same thing about where you are in the world at all times.

One often overlooked feature of peripheral neuropathy is that these maps often fail to match. Your eyes and inner ear may be creating maps that say one thing about where your body is in space, but when peripheral nerves are damaged, the input from muscles and joints may lead to a proprioceptive map that says something entirely different than your eyes and inner ear. When these maps do not match, it is difficult to unconsciously localize yourself in the world. This commonly results in problems with balance, coordination, and falls.

And when you can’t yourself in the world, the world can become a very scary place.

We design your NeuroRescue program to help you regain as much function from your peripheral nerves as possible. Perhaps more importantly, we also focus on helping restore appropriate maps, so you can better adapt to the world and lead a more functional and fulfilling life.

We use several types of technology and therapy to accomplish this goal. All of our treatments are validated by the latest neurological research.

We use Low Level Laser therapy to help restore the function of peripheral nerves. Laser therapy has been shown to be a safe, painless, and effective way to help rebuild the function of sensory nerves in many types of peripheral neuropathy (5). It has also been shown to be effective in restoring strength and reducing pain in compressive neuropathies such as carpal tunnel syndrome (6).

We use a number of different electrical therapies in the treatment of peripheral neuropathy. We use currents including Transcutaneous Electrical Nerve Stimulation (TENS) and Interferential Current (IFC) in order to control pain and improve sensory function. These have been validated in research as safe and effective treatments to decrease pain and restore function in various peripheral neuropathies (7).

When sensory nerve damage leads to impaired body maps, we need to take extra steps to make sure that you are stable and safe. Falls are very common for people suffering from peripheral neuropathy, often with devastating consequences (8). In every NeuroRescue program, we work hard to decrease your fall risk.

We use a host of advanced types of balance therapy and vestibular rehabilitation in our neuropathy NeuroRescue programs. Research shows that the vestibular system may be directly involved in certain cases of neuropathy (9), and the vestibular nerve may undergo similar types of degeneration, leading to dizziness and balance problems (10). We address these issues with specific vestibular rehabilitation, which can be very helpful to improve balance and coordination, as well as to decrease dizziness and vertigo (11).

We employ several different strategies for balance and vestibular rehabilitation. These can range from traditional lower extremity strength and balance exercises (12), all the way out to balance exercises that take place in a virtual reality environment (13).

Additional forms of neurostimulation have been shown to be effective for the treatment of peripheral neuropathy. Transcranial Magnetic Stimulation is one such therapy, where an MRI-strength magnet is used to apply a focused beam of electromagnetic energy through the skull and directly to the prefrontal cortex. This treatment is safe, comfortable, with minimal rare side effects. More importantly, it is extremely effective for controlling pain and reducing abnormal sensations seen in several types of peripheral neuropathy (14, 15). We have such great success with our TMS treatment that we installed our second TMS unit this year.

Structural rehabilitation therapy can also be very helpful in treatment of neuropathies, particularly if there is a compressive component to the problem. We engage in various types of soft tissue techniques, therapeutic exercise, and joint manipulation where necessary. In many cases, joint manipulation proves to be one of our most effective therapies (16).

Not all of these therapies are appropriate for all individuals with peripheral neuropathy. As there are many different types of neuropathy, it is impossible to use a cookie-cutter approach to properly treat these conditions. We use our diagnostic skills and technologies to create your unique NeuroRescue program, specific to your unique set of circumstances. This allows us to ensure that your treatment is safe, efficient, and effective.

How Does the NeuroRescue Program Work?

We design your unique NeuroRescue Program to be among the most comprehensive diagnostic and therapeutic protocols available today. We create individual NeuroRescue Programs based on a comprehensive analysis of every relevant neurological system and pathway, using gold-standard, cutting edge neurodiagnostic technologies and examination procedures and state-of-the-art therapies.

We begin with your Discovery Day, wherein we perform a comprehensive history of not only your condition, but your life on a timeline. This allows us to dive deeply into your case and see all of the factors that led to where you are now. It helps us uncover hidden problems and associated conditions that may be making it difficult for you to move your recovery forward.

Our examination allows us to identify the areas and pathways of your brain that are involved in your peripheral neuropathy. In all of our cases of assumed peripheral neuropathy, we begin by making certain that there are no central nervous system factors contributing to your symptoms. We do this by precisely quantifying the function of your visual, vestibular, and proprioceptive systems through computerized analysis of your eye movements, your inner ear reflexes, and your balance in a host of different sensory conditions.

We employ technologies including Videooculography and Saccadometry to measure several classes of eye movements. We use Video Head Impulse Testing to measure the function of your inner ear, and Computerized Dynamic Posturography to assess your balance in different sensory conditions.

We use NeuroSensoryMotor Integration testing to evaluate hand-eye coordination and cognition, and Virtualis testing to assess dynamic eye tracking and perception of vertical in a virtual reality environment.

We combine all of this with a comprehensive physical and neurological examination of your sensory, motor, autonomic, and cognitive systems. We review any relevant laboratory testing, radiological imaging, and prior neurodiagnostic testing, and integrate that information with our findings.

We use this information to identify which parts of your nervous system are working properly, which systems are struggling, and the precise point at which your systems fatigue.

We can then design a NeuroRescue Program that is unique and specific to your brain, and yours alone. Your NeuroRescue Program works to rejuvenate and reintegrate the damaged neurons and pathways in your central and peripheral nervous systems. It works to improve energy, endurance, and functional capacity within your involved fragile systems.

We use our technologies and procedures to not only see what we need to address, but also when it is time to stop and let you rest. We address your impaired neurological function from multiple angles of therapy, and provide metabolic support to improve neurological recovery.

While we cannot bring back neurons that have been lost, your NeuroRescue Program allows us to take the pathways that remain and maximize their efficiency and endurance. And by focusing on the integration of systems, we can do more than just get pathways working better, we can get them working together again. This gives us our best opportunity to return you to living a healthy, vibrant, and fulfilling life.

Your Next Best Step:

Living with a peripheral neuropathy can be challenging, but there is hope for recovery and remission. To see if the NeuroRescue Program is right for you, contact one of our patient care coordinators to schedule your Discovery Day.

And remember, it’s never too late to start getting better.