How Do Pre-existing Conditions Affect Your Personal Injury Case? - Diamond and Diamond Lawyers

How Do Pre-existing Conditions Affect Your Personal Injury Case?


The principle behind personal injury claims is a simple one: Make victims of the negligence of other parties whole again. But, what happens in cases in which the victim has a condition that existed prior to the most recent injury? Someone ordered to pay damages to an accident victim who was more susceptible than others to injury because of a pre-existing condition could question the fairness of such an outcome. Courts in Canada have two rules they follow when determining compensation for someone with a pre-existing condition.

Causation a key element of negligence

A determination of negligence is required in a personal injury case to hold a person responsible for the injuries suffered by the claimant. One of the elements necessary to proving negligence is causation. Causation is the link between the conduct of one party and the injury suffered by another. For instance, a driver reading a text message on a cellphone slams into the rear of vehicle stopped for a red light. The cause of injuries suffered by the occupants of the vehicle hit in the rear can be linked to the conduct of the text-reading driver.

If an occupant of the vehicle complained of back pain and was diagnosed as having a herniated disk, the facts would appear to point to the collision as the cause of the injury. Disputes arise in personal injury cases when lawyers for the party at fault in causing an accident discover a pre-existing injury, such as a bulging disk from a previous accident, making a victim more susceptible to an injury if the bulging disk herniates or ruptures due to the most recent collision.

The thin skull rule

The controlling principle of law in personal injury cases is that negligent parties take their victims as they find them. Known as the thin skull rule, the fact that one person might be more susceptible to an injury does not relieve a negligent party of liability.

Someone might argue against being held responsible for paying damages to a person who would probably have not suffered any injury were it not for the pre-existing condition. The thin skull rule prevents a negligent party from avoiding liability by blaming the victim for the injury.

Lawyers for accident victims with a pre-existing condition have the burden of proving the following in order to recover damages:

  • The nature of the pre-existing condition
  • The condition was stable prior to the latest accident
  • The accident caused a worsening of the condition

The burden of proof is simply recognition of the responsibility of the negligent party to restore the victim to his or her pre-accident condition rather than a better condition than existed before.

The crumbling skull rule

The courts will not compensate a person for a medical condition existing prior to an accident. This is an extension of the thin skull rule. A pre-existing condition that was unstable and would have worsened over time is subject to the crumbling skull rule when determining the extent of the negligent party’s liability.

Going back to the texting driver example, the crumbling skull rule would require medical evidence proving the bulging disk would have eventually herniated even without the impact of the rear-end collision for the negligent driver to avoid liability. A court might still award some measure of damages if the accident accelerated the herniation.

Speak to a personal injury lawyer about pre-existing conditions

If you have been injured and believe another party could be responsible, contact the personal injury lawyers at Diamond and Diamond. They are experienced lawyers capable of handling even complex cases involving pre-existing conditions. Call our 24/7 injury hotline at 1-800-567-HURT or visit our website to speak to someone now about your claim. Consultations are free, and we have offices located throughout Ontario.

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