A person does not lose the ability to document a collision-related injury merely because that person was unusually vulnerable or had a prior condition. The difficult question is not whether the medical history was perfect. It is which injury, activation, aggravation, symptoms, treatment, limitations, and expenses were caused by the collision rather than by the condition's independent course.

The central comparison is the person's condition and function before the collision, the changes after it, and the evidence connecting particular changes to the event.

Keep four concepts separate

  • Peculiar susceptibility: the person experiences an injury or an extent of harm that may differ from what another person would experience
  • Activation: a previously dormant or inactive condition becomes symptomatic after the event
  • Aggravation: an existing symptomatic condition becomes worse in a way attributed to the event
  • Independent condition: symptoms, treatment, or loss that would have occurred without the collision

The North Carolina Court of Appeals addressed a jury instruction on peculiar susceptibility in Hughes v. Webster. Whether an instruction or a particular measure of damages applies depends on the evidence and the issues presented in the case.

Construct a before-and-after chronology

  • Before the collision: diagnoses, symptoms, treatment, medication, imaging, restrictions, work, daily activity, planned care, and periods without symptoms
  • The event: reliable collision facts, body movement if documented, emergency observations, and immediate complaints without turning vehicle damage into a medical opinion
  • After the collision: symptom onset, examinations, findings, diagnoses, treatment, response, restrictions, missed work, function, and later events
  • Provider analysis: records reviewed, factual assumptions, alternative explanations, opinions, limitations, and remaining uncertainty

Preserve the complete medical history

Selective records can hide the baseline needed to separate prior loss from collision-related change. HHS explains access and amendment rights for many records in Your Medical Records. Preserve the record as received, identify apparent errors, and use the provider's amendment process rather than editing or replacing the original.

Rule of Evidence 803 includes provisions for statements made for medical diagnosis or treatment and for records of regularly conducted activity. The existence of a medical record does not resolve every causation, foundation, trustworthiness, or hearsay issue.

Connect opinions to an adequate foundation

Rule 702 addresses expert qualifications, helpfulness, sufficient facts or data, reliable principles and methods, and reliable application. A useful medical-causation analysis identifies the history and records considered, timing, objective and subjective findings, response to care, prior and later events, alternative causes, and the limits of the opinion. A legal article cannot determine medical causation for an individual.

Reconcile expenses separately from causation

Rule 414 limits evidence offered to prove past medical expenses to amounts actually paid on satisfied bills and amounts actually necessary to satisfy bills that remain unpaid. Keep charges, adjustments, payments, balances, liens, and reimbursement notices separate. An expense ledger does not by itself prove that every service was caused by the collision.

Avoid all-or-nothing descriptions

A prior condition is not automatically the cause of every later symptom, and a post-collision diagnosis does not automatically make the collision the cause of every later loss. Build separate rows for activation, aggravation, new injury, unrelated condition, treatment, function, expense, and future uncertainty, with the source and contrary evidence for each.

Compare a disputed later medical event

The related Fields v. Fields guide shows how a disputed later medical event can require a separate causation analysis from other collision-related injuries.

Rosensteel Fleishman Car Accident & Injury Lawyers provides information about consulting a Charlotte car accident attorney when a pre-existing condition, activation, aggravation, causation, or damages is disputed.

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