Insurance companies are businesses, not charities, and their primary goal is to minimize payouts—even when claimants have legitimate injuries. One of their most effective tactics is exploiting pre-existing conditions to argue that a victim's injuries were not caused by the accident. In Missouri, where at-fault drivers are responsible for damages, insurers routinely scrutinize medical histories to find any prior injury or degenerative condition that could justify reducing compensation. This strategy is particularly insidious because many people have some form of pre-existing ailment, whether it's a past back strain, arthritis, or an old sports injury. By shifting blame onto these conditions, insurers can drastically lower settlement offers or deny claims outright.

The legal principle behind this tactic is known as the "eggshell skull" doctrine, which states that a defendant must take a victim as they find them—meaning they're liable for all injuries, even if a pre-existing condition made the person more vulnerable. However, insurers often ignore this rule, hoping claimants won't know their rights. They might argue that a herniated disc was already present before the crash, even if it was asymptomatic, or that a prior concussion made post-accident headaches inevitable. These arguments are frequently exaggerated or taken out of context, but without strong medical and legal rebuttals, they can succeed. The key for accident victims is understanding how insurers manipulate pre-existing conditions and how to counter their tactics.

One of the most common ways insurers uncover pre-existing conditions is by requesting broad medical authorizations, giving them access to years of medical records. They'll comb through every doctor's visit, physical therapy note, or chiropractic adjustment looking for anything that could weaken the claim. A single mention of back pain from five years ago might be misconstrued as proof that a current spinal injury isn't accident-related. Victims should be cautious about signing unlimited releases and instead work with an attorney to provide only relevant records. Additionally, insurers often hire "independent" medical examiners (IMEs) who are anything but independent—these doctors are paid by insurers and frequently downplay accident-related injuries.

Missouri's modified comparative fault rule further complicates matters, as insurers may argue that a pre-existing condition makes the victim partially responsible for their own injuries. For example, if someone had mild osteoarthritis before the crash, the insurer might claim they were already at risk for severe joint damage, thus reducing the at-fault driver's liability. This argument is misleading because even if a condition existed, the accident could have aggravated it to a disabling degree. Proving causation requires meticulous medical documentation, including before-and-after medical imaging, expert testimony, and clear explanations from treating physicians. Without this, insurers will exploit any ambiguity to underpay claims.

An often-overlooked factor is how insurers use algorithmic claims evaluation tools to automatically flag pre-existing conditions and reduce settlement offers. These software programs, such as Colossus, assign values to injuries based on historical data, but they're programmed to minimize payouts by default. If a claimant's medical history includes keywords like "chronic pain" or "degenerative disc disease," the system may slash the offer before a human adjuster even reviews the file. Victims can combat this by ensuring their doctors explicitly document how the accident worsened their condition, using language like "acute exacerbation" or "traumatically induced." A skilled attorney can also demand transparency about how these tools influenced the offer.

Another insurer tactic is misinterpreting diagnostic imaging to downplay injuries. MRIs and X-rays often show age-related changes (like spinal degeneration) that are normal for many adults but don't necessarily cause pain. Insurers will point to these findings and claim the victim's symptoms were inevitable, ignoring the fact that the crash triggered new pain or dysfunction. Radiologists and treating physicians must clarify which findings are pre-existing but asymptomatic versus those directly linked to trauma. In some cases, functional capacity evaluations (FCEs) can demonstrate how the accident caused new limitations, even if structural damage was partially pre-existing.

Pre-existing mental health conditions are another target for insurers, especially in cases involving PTSD, anxiety, or depression after a severe crash. They may argue that a victim's prior struggles with depression mean their emotional distress isn't accident-related, even though traumatic events can worsen pre-existing mental health issues. Missouri law allows compensation for psychological injuries, but insurers will resist unless there's clear documentation from psychiatrists or psychologists linking the decline in mental health to the collision. Victims should seek therapy early and ensure their providers detail the accident's impact in their notes.

One surprising strategy insurers use is social media surveillance to dispute pre-existing injury claims. If a victim posted about running a 5K race years before the accident, the insurer might argue they were already physically active and thus couldn't have been severely injured. Alternatively, if they shared a gym photo after the crash, the insurer could claim they're exaggerating their injuries. Victims should be extremely cautious about social media activity during a claim, adjusting privacy settings and avoiding posts that could be misconstrued. Attorneys often advise clients to stay off social media entirely until the case resolves.

Workers' compensation claims can also complicate car accident cases, as insurers may argue that a prior workplace injury is the real cause of ongoing pain. For example, if a victim had a back injury at work years ago but fully recovered, the insurer might still try to connect it to the car crash. Medical records must clearly distinguish between old, resolved injuries and new ones caused by the collision. An attorney can help by obtaining vocational expert testimony to show how the accident—not past issues—led to current disabilities.

For older adults, insurers are especially aggressive in citing age-related degeneration as a reason to reduce payouts. They'll claim arthritis, osteoporosis, or spinal stenosis would have caused pain eventually, regardless of the accident. However, Missouri courts recognize that even if a person had age-related changes, the crash may have accelerated symptoms or caused new injuries. Doctors should document whether the victim was asymptomatic before the wreck and how their condition has objectively worsened since.

A little-known tactic is insurers delaying treatment approvals to create gaps in medical records, making it seem like the victim's injuries weren't serious. For instance, if an insurer drags out authorization for physical therapy, the victim might appear to have "recovered" during the delay, even though they were in pain the whole time. Keeping a detailed pain journal and pursuing treatment despite delays can counter this strategy. Victims should also demand written explanations for any denied treatments.

Ultimately, the best defense against pre-existing condition arguments is strong legal and medical advocacy. An experienced attorney can work with doctors to draft persuasive narratives explaining how the accident caused new injuries or aggravated old ones. They can also challenge biased IME reports and demand full disclosure of how insurers calculated their offers. In some cases, filing a bad faith insurance claim may be necessary if the insurer knowingly misrepresented medical evidence.

Missouri victims should never accept a lowball settlement without consulting a lawyer. Insurers bank on claimants giving up, but with the right strategy, even those with pre-existing conditions can secure fair compensation. The key is anticipating the insurer's tactics and building an unshakable case that proves the accident's true impact.