Neurological Testing Injury Causation: A Guide

Can Neurological Testing Help Establish Causation in a Personal Injury Trial?

A patient walks into a clinic after a motor vehicle collision with a problem no one can see from across the room. Their lower back hurts. Pain travels into the leg. Part of the foot feels numb. The leg seems weaker than it did before the crash.

Those symptoms may be medically important, but in a personal injury case another question eventually appears: Can the clinician objectively demonstrate that the nervous system has been affected?

That is where neurological examination and diagnostic testing can become important.

Reflex changes, dermatomal sensory abnormalities, measurable muscle weakness, imaging findings, and electrodiagnostic studies may help clinicians determine whether an injury involves a spinal nerve root or peripheral nerve. When those findings align with the mechanism of trauma, symptom timeline, anatomical distribution, and diagnostic imaging, they may also support a medically defensible causation opinion.

Neurological testing does not automatically prove that an accident caused an injury. Instead, it adds pieces to a larger clinical puzzle.

From Sciatica Symptoms to Neurological Evidence

Sciatica is often described as pain traveling from the lower back or buttock into the leg, but sciatica itself is a symptom pattern rather than one single disease.

A patient may develop radiating leg pain because of lumbar nerve-root irritation, disc herniation, spinal stenosis, piriformis-related irritation, peripheral nerve injury, or another neurological condition. Dr. Alex Jimenez’s discussion of radiculopathy and sciatica explains how nerve-root compression can produce pain, numbness, tingling, and weakness affecting the extremities.

That distinction matters in a personal injury case.

If someone develops leg pain after a rear-end collision, the timing alone does not establish that a lumbar nerve root was injured. The clinician still needs to determine what anatomical structure could be generating the symptoms and whether the examination supports that explanation.

A neurological examination helps shift the focus from simply asking, “Where does it hurt?” to asking, “What part of the nervous system appears to be malfunctioning?”

Reflex Changes Can Provide Objective Information

Deep tendon reflexes evaluate neurological pathways involving peripheral nerves, spinal nerve roots, the spinal cord, and muscles.

During a lower-extremity neurological examination, a clinician may compare reflex responses between the two sides of the body. An asymmetric or diminished response can become clinically meaningful when it corresponds with other neurological findings.

For example, a reduced ankle reflex combined with compatible sensory changes, muscle weakness, radiating pain, and appropriate imaging may support suspicion of a particular lumbosacral nerve-root problem.

The important word is combined.

A reflex abnormality by itself does not establish accident causation. Reflexes vary among patients, and abnormalities can exist for reasons unrelated to trauma. The clinician therefore considers the finding within the complete neurological picture.

Dr. Jimenez’s neuropathy presentation and neurological examination overview discuss reflex testing, sensory examination, motor testing, dermatomes, orthopedic testing, and patterns associated with radiculopathy. His clinical material similarly emphasizes that neurological examination can provide objective evidence of nerve-root involvement while recognizing that neurological deficits can also have previous or alternative causes.

That second point is critical in medical-legal causation.

Dermatomal Sensory Changes Help Identify the Suspected Nerve Root

A dermatome is an area of skin primarily associated with sensory input from a particular spinal nerve root.

When a nerve root becomes irritated or compressed, a patient may experience numbness, tingling, burning, altered sensation, or pain along a recognizable distribution.

During the examination, a clinician may compare sensation in different areas of both legs. If sensory loss follows a pattern consistent with the patient’s radiating symptoms, it gives the clinician another anatomical clue.

Research on lumbar radiculopathy describes sensory loss in a dermatomal pattern, motor deficits in a myotomal pattern, and changes in deep tendon reflexes as important components of the examination (Berry et al., 2019).

Dermatomes are not perfectly identical from one patient to another, however. Human anatomy overlaps. That means a clinician should not conclude that one area of numbness automatically identifies one exact spinal level.

Instead, the finding is stronger when multiple observations converge.

Muscle Weakness Can Help Demonstrate Functional Nerve Involvement

Pain is inherently personal. Muscle weakness can sometimes be evaluated more directly.

During manual muscle testing, clinicians examine movements associated with different nerve roots and peripheral nerves. They may evaluate hip movement, knee extension, ankle movement, toe extension, plantar flexion, and other functions depending on the suspected lesion.

Imagine a patient who had normal leg function before a collision but afterward develops radiating pain, numbness, and measurable weakness involving movements associated with the same suspected nerve root.

That pattern deserves investigation.

Dr. Jimenez’s article on sciatic nerve injury discusses how trauma involving the lower back, buttocks, or leg—including automobile and workplace injuries—can be associated with sensory changes, weakness, reflex impairment, and other neurological findings.

Again, weakness alone does not reveal its cause. Consider pain inhibition, prior neurological disease, diabetes, deconditioning, peripheral neuropathy, and other factors.

This is why differential diagnosis strengthens rather than weakens a causation analysis.

EMG and Nerve-Conduction Studies Add Another Layer

When the clinical picture remains uncertain, electrodiagnostic testing may sometimes be appropriate.

Electromyography, commonly called EMG, evaluates electrical activity within selected muscles. Nerve-conduction studies examine how electrical signals travel through peripheral nerves.

These studies can help clinicians determine whether neurological dysfunction is consistent with radiculopathy, peripheral nerve entrapment, polyneuropathy, or another disorder.

A major review by Dillingham, Annaswamy, and Plastaras (2020) explains that needle EMG is an important test for evaluating suspected radiculopathy. The authors describe EMG as highly specific but only moderately sensitive, noting that it complements spinal imaging and can help distinguish radiculopathy from peripheral neuropathy and nerve entrapment.

That distinction has major medical-legal importance.

A positive EMG that matches the patient’s neurological exam and anatomical symptoms may strengthen the clinical evidence for nerve-root dysfunction. But because sensitivity is not perfect, a negative EMG does not automatically prove that the patient never experienced a clinically meaningful radicular disorder.

Dr. Jimenez similarly describes electrodiagnostic testing in Radiculopathy: What Is It? as an extension of the physical examination that may help evaluate suspected neurological involvement.

MRI Shows Anatomy—Not Automatically Causation

MRI can provide another essential part of the story.

It may identify a disc protrusion, herniation, nerve-root narrowing, or another structural abnormality. But finding an abnormality on MRI does not automatically tell the clinician when it developed or whether it is responsible for the patient’s current symptoms.

This is where clinical correlation becomes essential.

Suppose an MRI shows an L5-S1 disc abnormality. If the patient also has symptoms, sensory changes, weakness, reflex findings, and electrodiagnostic evidence that anatomically correspond to the involved neural structures, the overall clinical picture becomes more persuasive than the MRI finding alone.

Conversely, an MRI abnormality that does not match the patient’s symptoms may be incidental or may require another explanation.

Dr. Jimenez’s sciatica and radicular back and leg pain overview specifically compares imaging findings with medical history and physical and neurological exam results.

Why This Matters in a Texas Personal Injury Trial

Medical causation can involve questions beyond ordinary everyday experience.

The Supreme Court of Texas has explained that expert medical evidence is generally required when the causal relationship between an accident and a medical condition falls outside common knowledge. In Guevara v. Ferrer, the court emphasized the importance of competent evidence connecting an event to the medical conditions for which damages are sought.

Texas Rule of Evidence 702 likewise permits qualified expert testimony when specialized knowledge can help the factfinder understand evidence or determine a fact in issue. Rule 705 also recognizes the importance of sufficient underlying facts or data to support the expert’s opinion.

For neurological injuries, those underlying facts can include:

• the mechanism and direction of traumatic forces;
• the timing and progression of symptoms;
• reflex findings;
• dermatomal sensory abnormalities;
• myotomal weakness;
• provocative neurological testing;
• MRI or CT findings;
• EMG and nerve-conduction findings;
• prior neurological history and pre-existing conditions; and
• documented functional changes following the accident.

No individual item needs to carry the entire causation opinion.

The strength comes from convergence.

Building the Neurological Causation Chain

A defensible causation analysis asks whether the story makes anatomical, temporal, and physiological sense.

The clinician considers the patient’s condition before the accident, the forces involved in the trauma, the onset of symptoms, neurological findings, diagnostic studies, alternative explanations, treatment response, and changes over time.

Dr. Jimenez discusses this approach extensively in El Paso Injury Causation: Connecting Accidents to Injuries, which emphasizes linking mechanism, objective findings, differential diagnosis, imaging, and longitudinal documentation, rather than assuming that every abnormality found after an accident was caused by it.

That distinction protects everyone involved.

• For patients, it supports accurate diagnosis rather than exaggeration.
• For attorneys, it creates medical records that can better withstand scrutiny.
• For clinicians, it respects beneficence and non-maleficence by basing treatment decisions on the patient’s actual neurological condition rather than litigation needs.

Multidisciplinary Evaluation in El Paso

At Injury Medical Clinic PA in El Paso, Dr. Alex Jimenez, DC, APRN, FNP-BC, CFMP, IFMCP, combines chiropractic training with his role as a board-certified Family Nurse Practitioner. This allows structural, musculoskeletal, neurological, and broader medical findings to be considered within an integrated clinical framework.

Dr. Maria Guadalupe Cardenas, MD, board-certified in Internal Medicine and Medical Director and Collaborative Physician, contributes medical oversight when systemic disease, metabolic conditions, medications, or other competing explanations may influence neurological symptoms.

That multidisciplinary approach is especially valuable when a case is complicated by diabetes, previous spinal degeneration, peripheral neuropathy, an earlier injury, or another condition that could mimic accident-related radiculopathy.

A Distinctive Advantage in El Paso: Medical Direction and Dual-Licensed Soft-Tissue Injury Expertise

What distinguishes Dr. Jimenez’s Injury Medical Chiropractic and Functional Medicine Clinic in El Paso, Texas, is its integrated approach to personal injury diagnosis, neurological evaluation, and rehabilitation. Unlike traditional chiropractic practices that focus primarily on spinal adjustments, the clinic operates under the medical direction of Dr. Maria Guadalupe Cardenas, MD, a board-certified internal medicine physician with more than 40 years of clinical experience. Dr. Alex Jimenez, DC, APRN, FNP-BC, CFMP, IFMCP, works alongside her, bringing an unusual combination of chiropractic and board-certified Family Nurse Practitioner credentials and expertise in soft-tissue injuries, spinal trauma, musculoskeletal disorders, and neurological dysfunction.

This multidisciplinary structure brings medical oversight, advanced diagnostic evaluation, chiropractic treatment, functional medicine, acupuncture, electroacupuncture, and individualized rehabilitation into a coordinated clinical setting. For patients experiencing sciatica, radiculopathy, or suspected nerve injuries following an automobile collision or workplace accident, this approach allows the clinical team to evaluate both structural damage and neurological abnormalities while investigating alternative causes of symptoms. For personal injury attorneys, integrating medical and chiropractic expertise can produce more comprehensive clinical documentation, identify objective findings, and support carefully reasoned medical causation opinions. The clinic offers a distinctive combination of dual-licensed clinical leadership, physician oversight, and integrated injury care in El Paso, emphasizing accurate diagnosis, patient-centered recovery, and medically defensible documentation.

Injury Medical Clinic PA | Dr. Alexander Jimenez, DC, APRN, FNP | El Paso Injury Care

The purpose is not to manufacture causation.

Its purpose is to investigate.

When the patient’s history, trauma mechanics, neurological examination, diagnostic imaging, electrodiagnostic evidence, and longitudinal recovery pattern point toward the same anatomical conclusion, clinicians can provide attorneys and patients with a clearer explanation of what happened—and why.

For an injured patient, that clarity may mean a more appropriate treatment plan, better mobility, less pain, and a safer path toward recovery.

For a personal injury attorney, it means something equally important: a medical causation opinion built not merely on symptoms, but on clinical reasoning and objective evidence.

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References

Berry, J. A., Elia, C., Saini, H. S., & Miulli, D. E. (2019). A review of lumbar radiculopathy, diagnosis, and treatment. Cureus, 11(10), Article e5934. https://doi.org/10.7759/cureus.5934

Dillingham, T. R., Annaswamy, T. M., & Plastaras, C. T. (2020). Evaluation of persons with suspected lumbosacral and cervical radiculopathy: Electrodiagnostic assessment and implications for treatment and outcomes (Part I). Muscle & Nerve, 62(4), 462–473. https://doi.org/10.1002/mus.26997

Guevara v. Ferrer, 247 S.W.3d 662 (Tex. 2007). https://law.justia.com/cases/texas/supreme-court/2007/2001030.html

Jimenez, A. (n.d.-a). El Paso injury causation: Connecting accidents to injuries. Dr. Alex Jimenez. https://dralexjimenez.com/accidents-and-injuries/el-paso-injury-causation-connecting-accidents-to-injuries/

Jimenez, A. (n.d.-b). Neuropathy presentation: El Paso, TX: Part II. Dr. Alex Jimenez. https://dralexjimenez.com/neuropathy-presentation-part-ii/

Jimenez, A. (n.d.-c). Radiculopathy and sciatica. Dr. Alex Jimenez. https://dralexjimenez.com/radiculopathy-and-sciatica/

Jimenez, A. (n.d.-d). Radiculopathy? What is it? Dr. Alex Jimenez. https://dralexjimenez.com/radiculopathy-what-is-it/

Jimenez, A. (n.d.-e). Sciatic nerve injury. Dr. Alex Jimenez. https://dralexjimenez.com/sciatic-nerve-injury/

Jimenez, A. (n.d.-f). Sciatica and radicular back and leg pain in El Paso, TX. Dr. Alex Jimenez. https://dralexjimenez.com/sciatica-and-radicular-back-and-leg-pain-in-el-paso-tx/

Jimenez, A. (n.d.-g). Why choose our clinical team? Dr. Alex Jimenez. https://dralexjimenez.com/why-choose-dr-jimenez-and-clinical-team/

Supreme Court of Texas. (2025). Texas rules of evidence (effective September 1, 2025). https://www.txcourts.gov/media/1456691/texas-rules-of-evidence-effective-912025.pdf