You are sitting in a doctor’s office, holding a stack of medical bills from a car crash that was not your fault. You are in severe pain. But when you get the call from the at-fault driver’s insurance adjuster, they drop a bomb on you.
They looked at your medical records. They saw that you went to a chiropractor for lower back pain three years ago. The adjuster politely informs you that they are denying your claim because your current pain is just a “pre-existing condition.”
It feels like a massive slap in the face. You know your body. You know that you were functioning perfectly fine before their client rear-ended you at a red light. Yes, you had a history of back stiffness, but this new pain is entirely different, sharper, and debilitating.
Can an insurance company legally use your medical history to deny you the money you need to heal?
The short answer is no but they are absolutely going to try. Having a pre-existing condition complicates a personal injury claim, but it does not destroy it. In fact, California law has specific protections designed to help people who were already vulnerable before an accident.
This guide breaks down exactly how insurance companies weaponize your past, the legal rules that protect you, and the steps you must take to secure a fair settlement when you have a complicated medical history.
The Insurance Adjuster’s Favorite Weapon
To win a personal injury case, you have to prove that the accident directly caused your injuries. Insurance companies know this, and they spend millions of dollars training their adjusters to break that link of causation.
If they can point to something else anything else that might have caused your pain, they can save their company a fortune. Your past medical history is their favorite scapegoat.
They will request your past medical records and aggressively hunt for specific buzzwords. They love finding terms like arthritis, degenerative disc disease, sciatica, or chronic pain.
Here is how their playbook works:
- The “Natural Aging” Argument: If you are over the age of thirty, your spine likely shows some signs of natural wear and tear on an MRI. The insurance company will point to this natural aging and claim the crash didn’t hurt you; you are just getting older.
- The “Flare-Up” Dismissal: If you had a bad knee from a college sports injury, and the crash shattered that same knee, the adjuster will try to label the severe new damage as a simple, temporary “flare-up” of your old sports injury.
- The Index Database Check: Insurance companies use a massive, shared national database called the ISO ClaimSearch. If you filed a minor injury claim ten years ago, they will find it, pull the records, and use it against you today.
They use these tactics to offer you a lowball settlement, hoping you will get frustrated and just accept a fraction of what your claim is actually worth.
The “Eggshell Skull” Rule: Your Ultimate Legal Shield
If you had a bad back before the crash, the insurance company will argue, “A normal, healthy person wouldn’t have been hurt by this minor fender bender.”
Legally, that argument is completely irrelevant.
In personal injury law, there is a bedrock principle known as the “Eggshell Skull” rule (also called the Eggshell Plaintiff doctrine). This rule states that a negligent driver takes their victim exactly as they find them.
Imagine two people get rear-ended at 15 miles per hour.
- Driver A is a perfectly healthy 25-year-old athlete. They walk away with a stiff neck that heals in two days.
- Driver B is a 60-year-old with brittle bones and a history of spinal fusion surgeries. The exact same impact shatters their vertebrae, requiring months of hospitalization.
Under the Eggshell Skull rule, the at-fault driver cannot complain that Driver B was fragile. The at-fault driver is 100% legally and financially responsible for all the severe damage they caused, even if a “normal” person wouldn’t have suffered the same fate.
If a crash takes your pre-existing condition and makes it worse, the person who caused the crash has to pay for making it worse. You are legally entitled to compensation for the aggravation or exacerbation of your old injury.
Understanding the Math: Apportionment
You cannot force the insurance company to pay for the medical treatment you were already going to need before the crash. They are only responsible for the new damage.
This concept is called apportionment. Your lawyer and your doctors have to separate your baseline pain (before the crash) from your new pain (after the crash).
| Condition Status | Who Pays for Treatment? | Example Scenario |
| Stable / Dormant | The at-fault driver’s insurance | You had arthritis but lived pain-free. The crash made it symptomatic. |
| Active / Ongoing | Split based on the increase in severity | You were doing therapy twice a month. Post-crash, you need it twice a week. |
| Unrelated / New | The at-fault driver’s insurance | You had a bad knee before, but the crash broke your arm. |
Separating this out requires expert medical testimony. Your doctors must clearly document what your physical capability was the day before the crash, and contrast it with your physical capability today.
The Trap of the “Tough Guy” Act (Why Honesty is Mandatory)
The single biggest mistake you can make in a personal injury case is lying about your medical history.
When you hire a lawyer or speak to an insurance adjuster, you might feel tempted to hide the fact that you threw your back out a few years ago. You might think, “If I don’t mention it, they won’t know, and my case will be stronger.”
This is a fatal error for two reasons:
- They Will Find Out: As mentioned earlier, insurance companies have access to vast databases and subpoena power. They will find your old medical records.
- You Destroy Your Credibility: If you lie about a past injury and the defense attorney catches you in a lie during a deposition, your entire case falls apart. The jury will assume that if you lied about your past, you are probably lying about your current pain, too.
Embrace your medical history. A skilled personal injury attorney can easily win a case involving a pre-existing condition, but they cannot win a case for a client who is caught committing fraud. Tell your lawyer everything on day one so they can build a strategy around the truth.
How to Build a Bulletproof Case
Protecting your settlement requires deliberate action on your part. You have to create a paper trail that proves exactly how the crash altered your life.
1.See Your Specialist Immediately:Do not rely solely on the ER.
The emergency room doctor is there to make sure you aren’t dying, not to evaluate the nuance of your prior disc herniation. Within 48 hours of the crash, schedule an appointment with the specific doctor who previously treated your pre-existing condition (e.g., your orthopedic surgeon or rheumatologist). They are uniquely qualified to document exactly how your baseline has changed.
2.Use Descriptive, Differentiating Language:Help your doctor take accurate notes.
When you speak to your doctor, do not just say, “My back hurts again.” The insurance company will use that against you. Be highly specific about how the pain is different. Say, “Before the crash, my pain was a dull ache at a level 3. Now, it is a sharp, stabbing pain at a level 8, and it shoots down my left leg, which it never did before.”
3.Sign Limited Medical Releases Only:Protect your irrelevant history.
The insurance adjuster will ask you to sign a “blanket” medical authorization form so they can review your records. Never sign this. They will dig into decades of your private medical history looking for dirt. Your attorney will ensure they only get a limited release, restricting them to records directly related to the injured body parts.
4.Obtain a Narrative Medical Report:
As your treatment progresses, your attorney will ask your doctor to write a formal narrative report. This isn’t just a chart note; it is a legally powerful letter where your doctor explicitly states, “Based on my medical expertise, the recent trauma directly aggravated the patient’s underlying asymptomatic condition, resulting in the current need for surgery.”
The Role of Diagnostic Imaging (MRIs and X-Rays)
In cases involving pre-existing conditions, especially spinal injuries insurance companies rely heavily on MRIs.
If you get an MRI after a crash, the radiologist will often note “degenerative changes” or “disc desiccation.” The insurance adjuster will read that report and claim your pain is just from old age.
However, diagnostic imaging is just a snapshot in time. Medical science universally recognizes that millions of people walk around every day with bulging discs or arthritis that they do not even feel. You can have a terrible-looking MRI but live a completely pain-free, active lifestyle.
If your condition was asymptomatic (causing no pain) before the crash, and the crash suddenly “lit it up” and made it painful, you are entitled to compensation. Your lawyer will use your employment records, gym memberships, and testimony from your friends and family to prove that regardless of what the MRI looked like, you were physically thriving before the negligent driver hit you.
Do Not Let the Insurance Company Bully You
A pre-existing condition is not a roadblock; it is simply a hurdle. You have every right to seek justice and financial recovery if a careless driver disrupted your life, exacerbated an old injury, and put you in a position where you cannot work or enjoy your day-to-day routine.
The worst thing you can do is accept a fast, lowball settlement just because the insurance adjuster sounded confident when they told you your claim was worthless. They are trained negotiators trying to save their company money. You need someone on your side whose only job is to protect your future.
If you are dealing with a complex injury claim in Orange County and the insurance company is blaming your past, you need to change the narrative. Contact Law Office of Steven K. Bloom and get exceptional results.
