Pre-Existing Condition and a Car Accident Claim: Aggravation

A negligent driver takes the person they hit as they find them. That is the eggshell plaintiff rule, followed in every state: if a crash that would have bruised a healthy person breaks the bones of a person with osteoporosis, the driver is liable for the broken bones. The driver does not get a discount because the person they injured was more vulnerable than average.

The rule has a corollary. The driver is liable for the harm the crash caused, not for the condition that existed before it. A person with a bad back before the crash who has a worse back after it recovers for the worsening, the aggravation, and not for the bad back they already had. Juries are instructed on this in most states: compensate the aggravation of a pre-existing condition, and if the aggravation cannot be separated from the underlying condition, compensate the whole.

That last instruction matters. Where the evidence cannot apportion between the old condition and the new injury, many states place the burden on the defendant to show what portion was pre-existing, and if the defendant cannot, the injured person recovers for the entire condition. The insurer's argument that the pain is all pre-existing is therefore answered not only by showing it is not, but by showing that the insurer cannot prove how much of it is.

The insurer's claims software and its adjusters treat a prior condition in the same body part as a discount. The adjuster obtains prior records, through the medical authorization most claimants sign without reading, and looks for any earlier complaint of neck pain, back pain, headache or the joint in question. A chiropractic visit five years ago, a prior car crash, a workers' compensation claim, a sports injury, all become the argument that the current symptoms are a continuation rather than a new injury.

Imaging is the other source. MRI and CT scans of the spine in anyone over thirty-five show degenerative changes, disc bulges, arthritis, which radiologists describe in their reports, and the insurer's doctor reads those findings as proof that the condition predates the crash. The findings usually do predate the crash. The question is whether they were causing symptoms, and the answer is in the records of the years before: a person who was working, active and not seeking treatment for the back was not symptomatic, whatever the MRI shows.

The insurer's independent medical examiner will typically conclude that the crash caused a temporary strain superimposed on a degenerative condition, that the strain resolved within weeks, and that the continuing symptoms are the degenerative condition. That opinion is answered by the treating doctors, who saw the patient before and after, and by the record of the years without treatment.

Suppose you are 52, had an episode of low back pain eight years ago that resolved after a few physical therapy visits, and have had no back treatment since. You were rear-ended at a light, and within days had low back pain radiating into your leg. An MRI showed a disc herniation at L5-S1 with degenerative changes at several levels. You had six months of therapy and an injection series, with $31,000 in medical bills, and continuing limitation.

The insurer obtained your records and offered $8,000, asserting the MRI showed a degenerative condition and the prior episode proved the back was already a problem. Your attorney assembled the eight years of records showing no back treatment, your employer's confirmation that you had worked without restriction, and the treating physiatrist's opinion that the herniation and radiating symptoms were new, caused by the crash, and superimposed on asymptomatic degeneration.

The claim was presented as an aggravation claim: the degenerative changes were pre-existing and asymptomatic, the herniation and the symptoms were caused by the crash, and the insurer could not apportion any part of the current condition to the prior episode. It settled after negotiation for a figure reflecting the full treatment and the lasting limitation. All figures are hypothetical; the pattern of a long symptom-free period defeating the pre-existing argument is the usual one.

A prior condition is managed by candor and documentation, not by concealment, which is the one approach that loses.

• Tell every treating doctor about the prior condition and how you were doing before the crash; the comparison in the chart is the evidence of aggravation.
• Do not deny a prior condition to an insurer or at a deposition; the records will be found, and the denial costs more than the condition.
• Do not sign an open medical authorization; provide the records for the relevant body part and period through your attorney.
• Gather proof of your pre-crash function: work records, activity records, the absence of treatment, and statements from people who knew you.
• Ask the treating doctors to address causation and aggravation expressly in their records, comparing before and after.
• Keep treatment continuous; a gap is read as the aggravation having resolved.
• Expect an IME and prepare for it; the examiner's report will say the symptoms are degenerative, and the treating doctors' response is planned in advance.

The eggshell plaintiff rule and the compensability of aggravation are followed in every state, but the handling of apportionment differs. Many states instruct juries that where the aggravation cannot be separated from the pre-existing condition, the defendant is liable for the whole; some place the burden of apportionment on the defendant expressly; a few leave it to the plaintiff to prove the aggravation's extent. The instruction the jury receives shapes how insurers value these claims in each state.

In no-fault states, the pre-existing condition argument is used at the threshold stage: the insurer contends the injury is not serious or permanent because it is degenerative, which can bar the claim against the at-fault driver entirely in Florida, New York, Michigan and New Jersey. The treating doctors' opinion on permanency, distinguished from the degenerative baseline, is the answer.

Prior claims are discoverable. A prior injury claim, a workers' compensation claim or a disability claim for the same body part will be found by the insurer's database searches, and the records from it compared with the current claim. Consistency between the prior claim's description of recovery and the current claim's description of the pre-crash baseline matters. Deadlines are the state's injury statute, one year in Tennessee and Kentucky, two in Texas, California, Florida and Georgia, three in New York and North Carolina.

The most common version of the pre-existing argument is the MRI report. Disc bulges, disc desiccation, facet arthropathy, spondylosis and similar findings appear on the spinal imaging of most adults past their thirties, symptomatic or not, and radiologists report them. The insurer's doctor reads the report as proof the condition is old. It is, and it is also beside the point.

The medical question is whether the crash caused symptoms in a spine that was not producing them before, or caused a new structural change, a herniation, an annular tear, a fracture, superimposed on the old ones. The treating doctors answer it by comparing the imaging with any prior imaging, by the correlation between the symptoms and the findings, and by the history. A person with no back complaints for years who has radiating leg pain within days of a rear-end crash has an injury the crash caused, whatever the MRI's other findings.

Where prior imaging exists, the comparison is decisive: a herniation present now and absent before is new. Where it does not, the absence of prior symptoms and treatment is the evidence. The insurer's argument depends on treating the MRI as a diagnosis of the cause; it is a picture of the structure.

A claim with a pre-existing condition is an aggravation claim, proven by the contrast between the records before the crash and the records after it, and defended by the insurer with the prior records and the imaging findings. The questions to answer early are what the prior records show, how long the symptom-free period was, and whether the treating doctors will address causation and apportionment. Most personal injury attorneys work on contingency and handle these arguments routinely.

Ask Legal Matters is a free claim-review request service, not a law firm. Requests may be shared with independent attorneys and legal services partners who handle inquiries in your state, and an attorney must evaluate the facts before anyone can say what the claim is worth. If an insurer is saying your injury was pre-existing, you can request a free claim review.

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