How Pre-Existing Conditions Affect Your California Personal Injury Claim

California follows what's known as the 'eggshell plaintiff' or 'thin skull' rule. This legal doctrine states that a defendant must take the victim as they find them. In other words, if you have a pre-existing condition that makes you more vulnerable to injury, the at-fault party is still responsible for the full extent of harm they caused—not just what an average person might have suffered. This principle has been upheld in countless California court cases and applies to all types of personal injury claims.

For example, if you have degenerative disc disease and a car accident causes a herniated disc that requires surgery, the at-fault driver cannot argue they should only pay for what a person without your condition would have experienced. They are liable for your actual injuries, including the aggravation of your pre-existing condition. This protection is fundamental to California personal injury law and ensures that vulnerable individuals are not left without recourse simply because they had prior health issues.

However, it's important to understand that while you can recover for the worsening of a pre-existing condition, you cannot recover for the condition itself. The key is proving that the accident caused a measurable change in your health status—whether that's increased pain, reduced mobility, need for additional treatment, or acceleration of a degenerative process that would have taken years to develop naturally.

When you have a pre-existing condition, your compensation focuses on the 'aggravation' or 'exacerbation' of that condition. This includes any new symptoms, increased severity of existing symptoms, need for additional medical treatment, lost work time due to the worsened condition, and reduced quality of life beyond what you experienced before the accident. California law recognizes that even if you had some baseline level of pain or limitation, making it worse constitutes a compensable injury.

Medical documentation becomes crucial in these cases. You'll need records showing your condition before the accident and detailed documentation of how it changed afterward. This might include imaging studies showing new damage, physician notes describing increased symptoms, treatment records for new interventions you didn't need before, and testimony from your doctors about causation. Expert medical testimony often plays a vital role in establishing that the accident, not the natural progression of your condition, caused the worsening.

You can also recover for 'acceleration' of a degenerative condition. For instance, if you had arthritis that would have eventually required surgery in 10 years, but the accident made surgery necessary now, you can recover for that acceleration. The same applies to conditions like back and neck injuries where pre-existing degeneration is common. The at-fault party cannot escape liability simply because your injury might have occurred eventually—they're responsible for causing it to happen now and for all the consequences that flow from that timing.

Insurance adjusters are trained to look for any mention of prior injuries or medical conditions in your records. They'll request your complete medical history, often going back 5-10 years or more. Their goal is to find evidence they can use to argue that your current symptoms are simply a continuation of a pre-existing problem rather than a new injury caused by their insured. This is one of the most common defense tactics in California injury claims, and it's why many legitimate claims get denied or undervalued.

Common strategies include pointing to any prior treatment for similar body parts, arguing that imaging studies show 'degenerative changes' that pre-date the accident, claiming your symptoms are consistent with your age and prior medical history, and offering settlements that only account for a small percentage of your damages. They may also use gaps in your medical treatment history against you, suggesting that if you weren't treating before the accident, your condition wasn't that serious, or if you delayed treatment after the accident, your injuries must not be significant.

Don't fall for these tactics. Insurance companies have a financial incentive to minimize payouts, and they know that many injury victims don't understand their rights under California law. This is where having an experienced personal injury attorney becomes invaluable. An attorney who handles these cases regularly knows how to counter these arguments with medical evidence, expert testimony, and legal precedent that supports your right to full compensation for the aggravation of your condition.

One of the biggest mistakes injury victims make is failing to disclose pre-existing conditions to their attorney or hiding them from medical providers. This approach always backfires. Insurance companies will obtain your medical records through legal discovery, and if they find undisclosed prior injuries, they'll use that lack of disclosure to question your credibility and honesty. In some cases, failure to disclose can even be considered fraud, which could result in your claim being denied entirely.

Be completely honest with your legal team from the start. Tell them about any prior accidents, injuries, medical conditions, or treatments related to the body parts injured in your current accident. This allows your attorney to develop a strategy that addresses these issues head-on rather than being caught off guard during negotiations or trial. Experienced attorneys know how to present pre-existing conditions in a way that supports rather than undermines your claim.

Similarly, be honest with your medical providers. When they ask about your medical history, provide complete information. Your doctors need to understand your baseline condition to accurately assess and document how the accident changed your health status. Medical records that show you were honest about your history are far more credible than records that appear to hide prior issues. Remember, having a pre-existing condition is not a problem—lying about it is.

Strong medical evidence is essential when you have a pre-existing condition. Start by obtaining copies of your medical records from before the accident. These establish your baseline condition and show what symptoms, limitations, and treatments you had prior to the incident. If you had imaging studies like X-rays or MRIs before the accident, these are particularly valuable as they provide objective evidence of your pre-accident condition.

After the accident, seek immediate medical attention and make sure your providers document not just your injuries, but specifically how your condition has changed. Your medical records should include statements like 'patient reports increased pain compared to baseline,' 'new symptoms not present before accident,' or 'condition has significantly worsened since accident.' This type of documentation directly addresses the aggravation issue and makes it much harder for insurance companies to deny that the accident caused a change in your condition.

Consider obtaining an independent medical examination (IME) from a physician who specializes in your type of injury. While insurance companies often request their own IMEs (which tend to favor their position), having your own expert can provide powerful testimony about causation. Your expert can review all your records, examine you, and provide an opinion about whether and how the accident aggravated your pre-existing condition. This is particularly important in cases involving brain injuries, spinal cord injuries, or other complex medical conditions.

California follows a 'pure comparative negligence' system, which means your compensation can be reduced by your percentage of fault for the accident. However, it's important to understand that having a pre-existing condition does not constitute 'fault' or 'negligence' on your part. Your prior medical history cannot be used to reduce your recovery under comparative negligence principles—it's simply not relevant to the question of who caused the accident.

That said, insurance companies sometimes try to conflate these issues. They might argue that because you had a 'weak' back or neck, you should have been more careful or should bear some responsibility for your injuries. This argument has no legal merit in California. The comparative negligence analysis looks only at conduct that contributed to causing the accident itself, such as speeding, distracted driving, or failure to yield. Your physical condition before the accident is not conduct and cannot be considered in determining fault.

Where comparative negligence does matter is in cases involving multiple accidents or injuries. If you were in a rear-end collision six months ago and are now in another accident, the insurance company for the second accident may try to argue that some of your current symptoms are from the first accident rather than the second. This requires careful analysis of your medical records and often expert testimony to apportion damages between the two incidents. An experienced attorney can help navigate these complex situations.

Under California Code of Civil Procedure Section 335.1, you generally have two years from the date of injury to file a personal injury lawsuit. This deadline applies regardless of whether you have pre-existing conditions. However, the presence of a pre-existing condition can sometimes complicate the question of when the 'injury' actually occurred, particularly in cases where symptoms develop gradually or where it's not immediately clear that an accident made a pre-existing condition worse.

In most cases, the statute of limitations begins running on the date of the accident. However, California also recognizes the 'discovery rule,' which can extend the deadline in situations where you didn't immediately know you were injured or didn't know the full extent of your injuries. For example, if you had chronic back pain before an accident and didn't realize the accident had caused additional damage until months later when an MRI revealed new disc herniations, the statute of limitations might not begin until you discovered that new injury.

Don't wait to pursue your claim. Even if you're unsure whether your worsened symptoms are from the accident or just your pre-existing condition acting up, consult with a personal injury attorney as soon as possible. Waiting too long can result in lost evidence, faded memories, and ultimately, losing your right to compensation entirely. An attorney can help you determine whether you have a viable claim and ensure you meet all applicable deadlines.

Pre-existing condition issues can arise in any type of personal injury case, but they're particularly common in certain types of accidents. Motor vehicle accidents frequently aggravate pre-existing back, neck, and joint conditions due to the forces involved in collisions. Even low-speed accidents can cause significant aggravation of degenerative conditions, particularly in older adults or those with prior injuries.

Premises liability cases often involve pre-existing conditions because falls can aggravate arthritis, prior fractures, and degenerative spine conditions. Workplace injuries are another common scenario, as repetitive stress injuries often build on pre-existing conditions, and workers' compensation insurers routinely try to deny claims by attributing symptoms to pre-existing issues rather than work activities.

Motorcycle accidents, truck accidents, and pedestrian accidents often result in severe trauma that can aggravate virtually any pre-existing condition. In catastrophic injury cases involving severe trauma, the presence of pre-existing conditions may actually increase the severity of injuries and the amount of compensation owed, as the eggshell plaintiff rule means the at-fault party is responsible for all consequences of their actions, even if those consequences are more severe due to the victim's pre-existing vulnerabilities.

Not all medical providers understand the legal implications of how they document injuries, particularly when pre-existing conditions are involved. Some doctors may write notes that inadvertently undermine your claim by attributing symptoms to pre-existing conditions without clearly distinguishing what's new or worsened since the accident. This is why it's important to work with providers who have experience treating injury victims and understand the importance of clear, detailed documentation.

When you see a doctor after an accident, clearly explain your pre-accident baseline condition and how your symptoms have changed since the accident. Be specific: 'Before the accident, I had occasional lower back stiffness in the mornings that would resolve after 30 minutes. Since the accident, I have constant severe pain that radiates down my left leg and prevents me from sleeping.' This helps your doctor understand and document the aggravation of your condition.

Your attorney can often recommend medical providers who understand these issues and provide appropriate documentation. These providers know to include specific language in their reports about causation, aggravation, and the relationship between the accident and your current condition. They're also more likely to be willing to provide testimony or written opinions if your case goes to litigation. While you should always choose providers based on the quality of care they provide, working with doctors who understand the legal process can significantly strengthen your claim.

When you have a pre-existing condition, settlement negotiations often become more complex and contentious. Insurance companies will typically make lower initial offers, arguing that they should only pay for the 'aggravation' portion of your damages, not the full value of your injuries. They may present calculations that attempt to separate your pre-existing condition from the accident-related aggravation, often in ways that dramatically undervalue your claim.

Don't accept these lowball offers without consulting an attorney. Insurance companies count on injury victims not understanding their rights and accepting inadequate settlements out of fear that their pre-existing condition will prevent them from recovering anything. In reality, California law entitles you to full compensation for all damages caused by the aggravation of your condition, including medical expenses, lost wages, pain and suffering, and loss of quality of life.

An experienced attorney can present evidence that demonstrates the full impact of the accident on your life, including before-and-after comparisons of your functional abilities, testimony from family members and friends about changes they've observed, economic analysis of your lost earning capacity, and expert medical testimony about the extent of aggravation and your future prognosis. This comprehensive presentation of evidence often results in significantly higher settlement offers than injury victims can obtain on their own. If the insurance company refuses to make a fair offer, your attorney can file a lawsuit and take your case to trial, where a jury will hear all the evidence and determine appropriate compensation.

If you have a pre-existing condition and have been injured in an accident, consulting with an attorney should be one of your first steps. Many injury victims wait too long, hoping they can handle the claim themselves or that the insurance company will be fair. Unfortunately, insurance companies rarely offer fair compensation without pressure, and by the time many victims realize they need legal help, they've already made statements or accepted offers that harm their case.

Look for an attorney with specific experience handling cases involving pre-existing conditions. During your initial consultation, ask about their experience with similar cases, their success rate, and their approach to handling pre-existing condition defenses. Most personal injury attorneys work on a contingency fee basis, meaning you don't pay anything unless they recover compensation for you. This makes legal representation accessible even if you're facing financial hardship due to your injuries.

Don't let fear of your pre-existing condition prevent you from seeking the compensation you deserve. California law protects your right to recover for the aggravation of pre-existing conditions, and experienced attorneys know how to build strong cases even when prior injuries are involved. The sooner you consult with an attorney, the better they can protect your rights, preserve evidence, and build a compelling case for full compensation. Contact our office today to discuss your case and learn about your legal options.