What If the Insurance Company Says Your Injuries Were Pre-Existing After an Ontario Car Accident?

Quick answer: A pre-existing condition does not automatically defeat an Ontario car accident claim. The questions are whether the crash caused a new injury, worsened an existing condition, accelerated symptoms, or turned a manageable condition into a disabling one. Medical records, imaging, family doctor notes, specialist reports, treatment records, and evidence about how your function changed after the crash can become important.

This article deals with what happens when an insurance company says your injuries were already there before a crash. For an overview of Ontario car accident claims, including accident benefits, lawsuits, compensation, timelines, and insurer issues, see our Ontario car accident lawyers page.

Why insurers raise pre-existing conditions after a car accident

Insurance companies will usually review a person’s medical history after a car accident. If the records reveal prior back pain, neck pain, arthritis, disc degeneration, headaches, anxiety, depression, chronic pain, old fractures, prior concussions, or previous treatment, the insurer may argue that the collision did not cause the ongoing symptoms.

Many people have medical issues before a crash. The important issue is if the accident changed the person’s condition, treatment needs, work ability, daily function, or long-term outlook.

People can have a pre-existing condition and still have a valid claim if their crash worsened the condition.

What does “pre-existing condition” mean in a car accident claim?

A pre-existing condition is a medical issue that had already existed before the accident. Examples can include prior neck or back pain, degenerative disc disease, arthritis, old fractures or orthopedic injuries, previous concussions, migraines, chronic pain, anxiety, depression, PTSD symptoms, fibromyalgia, prior surgery, or another condition that affected the person before the crash.

The mere existence of one of these conditions is not enough to prevent a case from being viable. The claim depends on what the person was like before the crash, what changed after the crash, and whether the medical evidence connects that change to the collision.

What is the thin skull rule?

The thin skull rule means the at-fault person generally takes the injured person as they find them.

This means that if someone is more vulnerable because of a pre-existing condition, the defendant cannot avoid responsibility just because a healthier person might have recovered faster or suffered less harm.

For example, a person with a vulnerable back may suffer worse symptoms after a collision than someone with no prior spine problems. That does not automatically make the injury non-compensable. If the crash worsened the condition or caused a new level of disability, the insurer still has to address the harm caused by the accident.

The Supreme Court of Canada discussed these principles in Athey v. Leonati, a leading Canadian causation case involving pre-existing back problems and motor vehicle accidents.

What is the crumbling skull argument?

The crumbling skull argument is different. An insurance company could argue that the person’s condition was already deteriorating and would have worsened even without the accident. If that argument succeeds, compensation may be reduced to reflect the decline that would have happened anyway.

This does not mean the insurer can simply point to an old MRI or prior complaint and deny the claim. The evidence has to address the person’s real pre-accident condition, the expected course of the condition, and what changed after the crash.

Degenerative findings on imaging do not automatically defeat a claim

Insurance companies can sometimes rely on imaging that demonstrates degeneration, arthritis, disc bulges, disc protrusions, stenosis, or other age-related findings.

However, many people could have degenerative changes on imaging before they have major symptoms. A scan can show that part of the body was vulnerable, but it does not always prove that the accident caused nothing.

The stronger evidence is often functional. Could the person work before the collision? Were they exercising? Driving? Caring for family? Sleeping normally? Managing household tasks? Needing regular treatment? Taking pain medication? Missing work?

What evidence helps prove the accident made the condition worse?

Pre-existing condition disputes are usually evidence-heavy. Helpful records can include family doctor notes, emergency records, physiotherapy records, chiropractic records, massage therapy records, specialist reports, imaging, medication records, employment records, disability forms, and records from before and after the accident.

Useful evidence can include changes in work hours, ability to perform job duties, sleep, driving, lifting, bending, sitting, standing, walking tolerance, exercise, household tasks, caregiving, pain medication, mental health, treatment frequency, and need for help from family members.

What if the insurer says your pain was already there?

The insurer may argue that the same body part was already painful before the collision. That is common in neck, back, shoulder, hip, knee, headache, concussion, chronic pain, and psychological injury claims.

The response depends on the facts. A person may have had occasional symptoms before the crash but constant symptoms afterward. They may have worked full-time before the collision but been unable to return afterward. They may have needed minimal treatment before the accident but ongoing rehabilitation afterward.

How pre-existing conditions affect accident benefits

Pre-existing conditions can also become an issue in the accident benefits claim.

An accident benefits insurer may argue that treatment is not reasonable and necessary because the symptoms were already present before the crash. However, pre-existing conditions can actually be helpful in having an individual removed from the Minor Injury Guideline if it makes it more difficult for them to recover from their accident related injuries.

What if you had prior anxiety, depression, or PTSD?

Pre-existing psychological symptoms do not defeat a car accident claim. A collision can worsen anxiety, depression, PTSD symptoms, driving fear, sleep problems, irritability, panic symptoms, or chronic pain-related distress. The issue is whether the accident caused a meaningful change in the person’s mental health, function, treatment needs, or ability to work and participate in daily life.

What if the insurer requests old medical records?

Insurers often request prior medical records when causation is disputed. Some records may be relevant, especially where the same body part or condition was treated before the crash.

That does not mean every broad request should be accepted without review. The scope of the request should be connected to the issues in the claim. A lawyer can help determine what records are relevant, what objections should be raised, and how to respond if the insurer is using old records unfairly.

FAQ About Pre-Existing Conditions After an Ontario Car Accident

Can I still sue if I had a pre-existing condition before the crash?

Yes. A pre-existing condition does not automatically prevent a lawsuit. The issue is whether the crash caused a new injury, worsened the condition, accelerated symptoms, or increased your disability.

What if my MRI showed degeneration before the accident?

Degeneration on imaging does not automatically defeat a claim. Many people have degenerative findings without major symptoms. The key evidence is often whether your pain, treatment needs, work ability, and daily function changed after the crash.

What if I already had back or neck pain before the car accident?

You may still have a claim if the accident made your symptoms worse or caused new limitations. The case will usually depend on medical records and a before-and-after comparison.

What if the insurance company says my injuries are age-related?

Age-related findings are common, but they do not answer the full legal question. The insurer still needs to address whether the collision worsened the condition or caused additional loss.

What is the thin skull rule in Ontario car accident claims?

The thin skull rule means the at-fault person generally takes the injured person as they find them. If a person is more vulnerable because of a pre-existing condition, that vulnerability does not automatically excuse the defendant from responsibility for accident-related harm.

What is the crumbling skull argument?

The crumbling skull argument is the insurer’s argument that the condition would have worsened even without the accident. If proven, compensation may be reduced for deterioration that would have happened anyway.

Can a car accident make arthritis, stenosis, or disc degeneration symptomatic?

It can, depending on the facts and medical evidence. The issue is whether the accident caused a meaningful change in symptoms, function, treatment needs, or ability to work.

Can pre-existing anxiety or depression be part of a car accident claim?

Yes. If a car accident worsens pre-existing anxiety, depression, PTSD symptoms, sleep problems, driving fear, or psychological distress, those changes may be relevant to the claim.

Talk to an Ontario car accident lawyer about a pre-existing injury dispute

Pre-existing condition arguments can make an Ontario car accident claim more difficult, but they do not automatically end the case. The claim needs a careful review of medical records, imaging, treatment history, work function, daily activities, accident benefits, and the before-and-after evidence.

For more information, contact Foster Injury Law for a free consultation.

This article is for general information only and is not legal advice. Every car accident claim involving pre-existing conditions depends on the medical evidence, the accident facts, and the applicable law.

Author: Lane Foster, Foster Injury Law