Peripheral neuropathy

Have you ever had a weird feeling like your hands and feet are asleep, even when you're totally awake and moving around? Or maybe you've felt tingling, burning or strange zaps in your fingers or toes? Well, that might be what's called peripheral neuropathy.

Peripheral neuropathy is a term to categorize over 100 different types of neuropathies. This damage messes with the communication between your brain and your muscles through the peripheral nervous system.

Picture it like a messed-up phone line. The messages from your brain, such as feeling touch, pain or temperature, don't come through clearly or sometimes not at all. And when that happens, you can have neuropathy symptoms from feeling numb and weak to having trouble keeping your balance.

How the peripheral nervous system works

The peripheral nervous system acts as a bustling network linking your brain and spinal cord (the central nervous system) to the rest of your body, facilitating continuous communication and activity. This pathway comprises two main lines:

• Motor (efferent): Conveys instructions from the brain and spinal cord to muscles and organs. This line sends commands through motor nerves, directing muscle movements (such as waving your hand) or regulating organ activities like heart rate.
• Sensory (afferent): Responsible for transmitting information to the brain and spinal cord. Sensory receptors detect stimuli from the environment (like the touch of sunlight) and relay these signals as electrical impulses via sensory nerves to the brain.

However, the peripheral nervous system's communication pathway is not merely a straightforward exchange. It consists of two primary divisions:

• Somatic nervous system: Governs voluntary actions such as walking, speaking or engaging in cognitive activities like playing video games.
• Autonomic nervous system: Manages involuntary functions like digestion, respiration and heart rate, akin to an autopilot system ensuring seamless operations even without conscious attention.

The autonomic nervous system further branches into two components:

• Sympathetic nervous system: Activated in fight-or-flight scenarios, preparing the body for action by increasing heart rate, respiration and perspiration.
• Parasympathetic nervous system: Responsible for restoring calmness post-activity, slowing heart rate, respiration and aiding in digestion.

Various factors including infections, injuries, high blood sugar levels and genetic predispositions can result in nerve damage, leading to peripheral neuropathy.

Types of peripheral neuropathy

Neuropathy refers to a condition involving damage or dysfunction of nerves, often resulting in symptoms such as numbness, tingling, weakness or pain. Peripherial neuropathy is the umbrella for several types of neuropathies. The most common types of neuropathy include:

• Diabetic neuropathy: Specifically linked with diabetes, diabetic neuropathy stands as one of the most prevalent complications of the disease, predominantly affecting the feet and legs initially before potentially impacting nerves throughout the body.
• Autonomic neuropathy: Targeting nerves governing involuntary bodily functions like heart rate, blood pressure, digestion and bladder control, autonomic neuropathy can lead to symptoms such as dizziness, fainting, gastrointestinal disturbances, sexual dysfunction and impaired sweating.
• Hereditary sensory motor neuropathy: Also recognized as inherited or familial neuropathy, hereditary sensory motor neuropathy arises from genetic mutations transmitted through families, exemplified by conditions like Charcot-Marie-Tooth disease and personal muscular neuropathies.
• Toxic neuropathy: This type of neuropathy results from exposure to specific substances such as heavy metals (e.g., lead, mercury), medications (e.g., certain chemotherapy drugs, antibiotics), industrial chemicals or alcohol consumption.
• Idiopathic neuropathy: Idiopathic neuropathy occurs when the cause of neuropathy remains unknown despite thorough evaluation, leaving it labeled as idiopathic neuropathy without an underlying cause.
• Neuralgic amyotrophy (NA): Also known as Parsonage-Turner syndrome (PTS), this neuropathy condition is thought to be caused by abnormal autoimmune reactions that damage peripheral nerves. Neuralgic amyotrophy neuropathy leads to extreme pain and muscle weakness in the shoulder.

What are the four stages of peripheral neuropathy?

Peripheral neuropathy unfolds across distinct stages, necessitating an understanding of its progression for tailored treatment from your provider.

Each stage of peripheral neuropathy delineates severity and symptom advancement:

• Stage 1: Initially, mild numbness and discomfort may manifest in the hands and feet, with a subtle sense of something feeling awry. Symptoms of peripheral neuropathy might be inconspicuous enough to overlook during this phase.
• Stage 2: Pain becomes more pronounced and consistent, reaching a point where it cannot be disregarded.
• Stage 3: Intensified pain characterizes this stage, making daily tasks challenging due to its severity.
• Stage 4: At this stage of peripheral neuropathy, complete numbness and sensory loss in the hands and feet prevail, increasing the risk of amputation.

Though peripheral neuropathy lacks a cure, its progression can be slowed by promptly seeing your provider upon noticing potential symptoms of peripheral neuropathy.

Peripheral neuropathy symptoms

Symptoms of peripheral neuropathy can vary contingent upon the nerves affected. Damage to sensory or motor nerves may show symptoms such as:

• Heightened sensitivity to touch
• Sensation akin to wearing socks or gloves despite not doing so
• Muscle weakness
• Numbness and tingling sensations in the hands or feet
• Sharp or piercing neuropathic pain
• Throbbing or burning neuropathic discomfort

Autonomic nerve damage may manifest as:

• Bowel, bladder or digestive complications
• Excessive perspiration or inability to sweat
• Intolerance to heat
• Low blood pressure resulting in lightheadedness or dizziness

If any of these potential neuropathy symptoms arise, prompt consultation with a doctor is imperative to explore appropriate treatment options.

Peripheral neuropathy diagnosis

During your physical exam, your doctor will inquire about potential symptoms of peripheral neuropathy and factors that exacerbate or alleviate them. Also, they may explore your history of exposure to toxins, alcohol or tobacco consumption, any past infections or diabetes diagnosis, and any familial neurological diseases.

To further investigate potential neuropathy, various blood tests might be prescribed to screen for conditions like diabetes; vitamin deficiencies; liver, thyroid or kidney dysfunction; infections; or indications of abnormal immune system function.

Additionally, your doctor may suggest nerve function tests and imaging studies to ascertain the type, site and severity of any nerve impairment. These neuropathy assessments aid in formulating an accurate diagnosis and developing an appropriate treatment plan.

Nerve function tests

• Nerve conduction velocity (NCV) test: This test measures signal strength and speed along specific large motor and sensory nerves and reveals the location of nerve damage.
• Electromyography (EMG) test: For this test, tiny needles connected to electrodes are inserted into specific muscles to record their electrical activity at rest and during contraction. Test results show any abnormal muscular electrical and can help differentiate between muscle and nerve disorders.

Imaging tests

• MRI: An MRI of the spine can reveal tumors or nerve root compression, also known as a pinched nerve, that could be causing your peripheral neuropathy.
• CT scan: CT scans of the spine can show herniated discs, spinal stenosis (narrowing of the spinal canal), tumors and bone irregularities that may affect nerves.

Peripheral neuropathy treatment

Although there is no way to repair the nerves through treatment of neuropathy, you can stop further nerve damage and relieve neuropathy pain. The goal of neuropathy treatment is to manage what’s causing your neuropathy and improve symptoms.

Your doctor may use a combination of medications, therapy or surgery to treat peripheral neuropathy.

Therapy options for neuropathy

Therapy may be often used to improve motor skills, strengthen muscles or relieve symptoms. Therapies your doctor may recommend for neuropathy include:

• Acupuncture, massage and cognitive behavioral therapy to help with neuropathic pain management
• Hand or foot braces to stabilize the muscles and nerves
• Orthopedic shoes to improve walking difficulties and help prevent foot injuries
• Physical therapy to learn muscle stretching and strengthening techniques that can help with pain relief
• Regular exercise to deliver more blood, oxygen and nutrients to nerve endings, improve muscle strength and limit muscle atrophy
• Splints for carpal tunnel problems to reduce pressure on the compressed nerve and allow it to heal
• Surgery for pinched nerves or carpal tunnel syndrome

Peripheral neuropathy medication options

Medications can be used to improve neuropathy symptoms and relieve pain, including:

• Antidepressants
• Pain medications, such as ibuprofen or naproxen
• Anti-seizure medications, such as gabapentin and pregabalin
• Topical creams or skin patches for neuropathic pain

Managing peripheral neuropathy

Regular foot inspections are crucial for individuals with peripheral neuropathy to identify any potential injuries or infections. Due to diminished sensation that may develop over time with neuropathy, it's possible not to notice a wound or injury.

For instance, individuals with diabetes and peripheral neuropathy could inadvertently step on objects without sensing it. If self-inspection becomes challenging, enlisting the assistance of a family member or friend or utilizing a mirror can aid in thorough examination.

Moreover, it's advisable for individuals with peripheral neuropathy to wear well-fitted shoes and refrain from walking barefoot to mitigate the risk of injury. These preventive measures are instrumental in maintaining foot health and minimizing the likelihood of complications from neuropathy.