Introduction: Who Should Seek Diagnostics

If you’ve been experiencing unusual sensations like numbness, tingling, or burning pain—especially in your hands or feet—it’s important to see a healthcare provider as soon as possible. These early symptoms can signal that something is affecting your nerves, and getting diagnosed early gives you the best chance of preventing further damage and managing your condition effectively.^[1]

People who should particularly consider diagnostic testing include those with diabetes, as high blood sugar levels over time are one of the most common causes of nerve damage. If you have diabetes and you notice pain, tingling, or loss of sensation in your feet, or if you experience weakness or difficulty with balance, these are signs you should discuss with your doctor right away.^[5]

Beyond diabetes, you should seek diagnostics if you have other risk factors or conditions. This includes people with thyroid problems, long-term alcohol use, vitamin deficiencies, a history of viral infections like shingles or HIV, or anyone taking medications known to affect nerves, such as certain chemotherapy drugs. If you’ve had a physical injury that might have damaged nerves, or if you’ve been exposed to toxic chemicals, these are also reasons to get evaluated.^[7]

Even if you don’t have these conditions, anyone experiencing muscle weakness, trouble with coordination, problems with balance, or unusual sensitivity to touch should be examined. Symptoms like feeling lightheaded, having digestive issues, or noticing changes in bladder or sexual function can also indicate nerve involvement and warrant professional assessment.^[2]

It’s especially important for older adults to pay attention to these symptoms, as the risk of developing nerve problems increases with age. About 5 to 7 percent of people aged 45 and older experience some form of peripheral nerve issue, making regular check-ups increasingly valuable as you get older.^[2]

Diagnostic Methods for Identifying Nerve Damage

When you visit your healthcare provider with concerns about nerve problems, the diagnostic process begins with a thorough conversation about your symptoms and medical history. This is a crucial first step, as it helps your doctor understand the full picture of what you’re experiencing and what might be causing it.^[9]

Medical History Review

Your healthcare provider will ask detailed questions about your symptoms, including when they started, how they’ve changed over time, and how they affect your daily life. They’ll want to know about your lifestyle habits, such as alcohol consumption and smoking, because these can contribute to nerve damage. Your doctor will also review any medications you’re taking, as some drugs are known to cause nerve problems as a side effect.^[9]

Family history is another important piece of the puzzle. Some forms of nerve disease run in families, so knowing whether relatives have experienced similar issues can help guide the diagnostic process. Your doctor will also ask about any exposure to toxins or chemicals, recent infections, and any other health conditions you may have, such as diabetes or autoimmune diseases.^[3]

Physical and Neurological Examination

After taking your history, your doctor will perform a physical examination that focuses on your nervous system. This neurological exam is designed to check how well your nerves and muscles are working together. Your healthcare provider will test your reflexes by tapping certain areas with a small hammer. They’ll check your muscle strength by asking you to push or pull against resistance, and they’ll evaluate your muscle tone to see if there’s any unusual tightness or weakness.^[9]

The exam will also assess your ability to feel different sensations. Your doctor may use various tools to test whether you can sense light touch, vibration, temperature, or pain in different parts of your body. This helps determine which types of nerve fibers might be affected—sensory nerves that carry feeling, motor nerves that control movement, or autonomic nerves that manage automatic body functions like heart rate and digestion.^[1]

Balance and coordination tests are also part of the neurological examination. You might be asked to walk in a straight line, stand on one foot, or perform specific movements to see how well your nervous system is coordinating your body’s actions. Problems with balance can indicate that nerves in your feet and legs aren’t sending proper signals to your brain about where your body is in space.^[9]

Blood Tests

Blood tests are often ordered to look for underlying causes of nerve damage. These laboratory tests can detect diabetes by measuring blood sugar levels, identify vitamin deficiencies (particularly vitamins B1, B6, B12, and E), check thyroid function, and look for signs of inflammation or metabolic problems that might be affecting your nerves.^[9]

Blood tests can also reveal autoimmune conditions, infections like Lyme disease or hepatitis C, and other systemic issues that could be contributing to your symptoms. In some cases, specialized blood work may be done to check for inherited conditions or exposure to toxins.^[7]

Nerve Function Tests

One of the most important diagnostic tools for nerve problems is electromyography, commonly called an EMG. This test measures the electrical activity in your muscles to determine if nerve damage is present and how severe it might be. During an EMG, a thin needle electrode is carefully inserted into the muscle being tested. This allows the device to record the electrical signals that your muscles produce when they contract and when they’re at rest.^[9]

The EMG is typically performed alongside a nerve conduction study. For this test, flat electrodes are placed on your skin, and a small, low-level electrical current is used to stimulate your nerves. The test records how quickly and effectively your nerves can carry electrical signals. Damaged or diseased nerves will show slower conduction speeds or reduced signal strength, helping doctors pinpoint where problems exist and how extensive the damage is.^[9]

These electrical tests can help distinguish between different types of nerve problems. They can show whether the issue involves the protective covering around nerves (called myelin) or the nerve fibers themselves (called axons). This distinction is important because different types of nerve damage may have different causes and require different treatment approaches.^[2]

Other Specialized Tests

An autonomic reflex screen may be used if your doctor suspects that the nerves controlling automatic body functions are affected. This test evaluates how well these nerves are working by checking things like blood pressure changes when you stand up, heart rate variations, and other automatic responses.^[9]

A sweat test can measure your body’s ability to produce sweat, which is controlled by autonomic nerves. Sensory tests record how you perceive different types of stimulation, such as touch, vibration, cooling, and heat. These tests help create a complete picture of which nerve functions are impaired and which are still working properly.^[9]

Imaging Tests

While nerve problems themselves don’t always show up on imaging studies, tests like CT scans (computed tomography) or MRI scans (magnetic resonance imaging) can be extremely helpful. These tests create detailed pictures of the inside of your body and can identify structural problems that might be causing nerve damage.^[9]

Imaging can reveal herniated disks in your spine that might be pressing on nerves, tumors or growths that could be compressing nerve pathways, or problems with blood vessels that supply nerves with oxygen and nutrients. They can also help rule out other conditions that might be causing similar symptoms.^[9]

Nerve Biopsy

In some cases, when other tests haven’t provided clear answers, your doctor may recommend a nerve biopsy. This procedure involves removing a small sample of nerve tissue, usually from the lower leg, for examination under a microscope. A nerve biopsy can provide definitive information about what’s happening to the nerve fibers and can help diagnose certain specific conditions that affect nerves.^[9]

Similarly, a skin biopsy may be performed to detect damage to small nerve fibers that are located in the skin. This is a less invasive procedure than a nerve biopsy and can be particularly useful for diagnosing certain types of nerve fiber damage that don’t show up well on other tests.^[4]

Diagnostics for Clinical Trial Qualification

When patients are being considered for enrollment in clinical trials, a standardized set of diagnostic tests is typically required. These tests serve several purposes: they confirm that patients have the condition being studied, they establish a baseline measure of how severe the condition is, and they help ensure that participants are similar enough to allow researchers to draw meaningful conclusions from the trial results.

For clinical trials studying nerve conditions, baseline nerve function testing is almost always required. This typically includes EMG and nerve conduction studies to objectively measure the degree of nerve damage at the start of the trial. These measurements provide a reference point that researchers can use to determine whether an experimental treatment is making a difference.^[9]

Blood tests are standard for clinical trial screening. These usually include comprehensive metabolic panels to check kidney and liver function, complete blood counts to assess overall health, tests for diabetes and blood sugar control, and measurements of vitamin levels. Depending on the trial, specialized blood tests may also be required to look for specific markers or to rule out conditions that would make it unsafe for someone to participate.^[7]

Many trials require imaging studies such as MRI or CT scans to document the state of the nervous system and rule out other conditions. For trials testing treatments for nerve pain, questionnaires and scales that measure pain intensity, quality of life, and functional ability are commonly used. These standardized assessment tools allow researchers to track changes over time in a consistent way across all trial participants.^[9]

Clinical trials often have strict eligibility criteria based on diagnostic findings. For example, a trial might only accept participants whose nerve conduction studies show damage within a certain range of severity, or who have had symptoms for a specific length of time. The diagnostic tests help ensure that only appropriate candidates are enrolled, which protects participant safety and improves the likelihood that the trial will produce clear, useful results.^[7]

In some research studies, additional specialized tests may be required that aren’t part of standard clinical care. These might include detailed autonomic function testing, specialized sensory testing equipment, or genetic testing to identify specific subtypes of nerve conditions. While these tests help advance scientific understanding, they’re not typically necessary for diagnosis in everyday clinical practice.^[9]