What Happens If a Car Accident Aggravates a Pre-Existing Injury in Illinois?

 Posted on August 23, 2026 in Car Accidents

Car crashes might not just cause new injuries; they can also make old ones worse. A back problem that was manageable before a crash may suddenly require more treatment or cause pain that was not there before. In Illinois, you can seek compensation when a car accident aggravates a pre-existing injury or condition.

When you already have a medical condition, showing how your life changed after a collision can be an important part of your claim. A Chicago, IL car accident attorney can review your medical history and help you understand your options after a crash.

Can You Recover Compensation for a Pre-Existing Injury in Illinois?

Illinois law allows an injured person to recover damages when an accident makes an existing condition worse. The key issue is the harm caused by the new accident, not whether you were in perfect health beforehand.

The state tells jurors that they may not deny or limit damages because an accident aggravated a pre-existing condition. The same rule also applies when an existing condition made someone more likely to be injured. 

This can apply to many medical conditions. Someone with an old knee injury, for example, may have been walking normally before a crash but then need surgery afterward. The earlier knee injury does not erase the harm caused by the new collision, and should be taken into account when determining compensation.

How Can a Pre-Existing Injury Affect Your Illinois Car Accident Claim?

An insurance company may look closely at your medical history if you claim that a crash made an existing condition worse. The insurer may try to argue that your current pain came from the earlier injury rather than the accident.

This is why your medical records become especially important. Records from before the crash can show your condition at the time, while records after the accident can document new symptoms and changes in your health.

What Evidence Can Show That an Accident Made an Old Injury Worse in Illinois?

Your medical history does not need to be perfect, but being open about previous injuries can help doctors explain what changed after the accident.

Evidence that may help includes:

• Medical records showing your condition before the crash

• Records of emergency care and follow-up treatment after the accident

• X-rays, MRIs, or other diagnostic tests

• Notes from doctors or physical therapists describing changes in your symptoms

• Employment records showing times you could not work because of the aggravated injury

Your daily activities may also help show the difference. Perhaps you could work a full shift or handle household tasks before the accident, but now you struggle with them. That change may support your claim.

What Damages Can You Recover for an Aggravated Injury in Illinois?

A claim focuses on the harm the accident added to your existing condition. For example, someone who occasionally received treatment for an old back injury would not seek payment simply because that condition existed before the crash. The claim would instead focus on how the collision made the condition worse.

Damages may include added medical expenses and income lost while you recover. Compensation may also cover pain and other effects of the aggravated injury. The amount should reflect the harm caused by the new accident.

How Long Do You Have to File an Illinois Car Accident Lawsuit?

Under 735 ILCS 5/13-202, Illinois generally gives an injured person two years to file a personal injury lawsuit. A pre-existing condition does not normally extend that deadline.

Waiting can also make your claim harder to document. Starting the process early gives your attorney more time to gather all of your medical records and evidence from the time of the crash and make sure that no evidence is lost. 

Schedule a Free Consultation With a Chicago, IL Car Accident Attorney

An old injury should not keep you from seeking compensation when a car accident makes your condition worse. The South Side of Chicago, IL personal injury lawyer at Kadzai Law Group, LLC can review your medical history and show how your condition changed after the crash. Call 312-229-0050 to schedule a free consultation and learn more about your options after an Illinois car accident.