A prior back injury does not bar your claim. California law allows you to recover for the aggravation of a pre-existing condition, and the driver who hit you is responsible for the harm the crash actually caused to the back you actually had. The standard jury instruction says it directly: if the plaintiff had a condition that was made worse by the defendant’s conduct, the plaintiff recovers for the worsening. A back that was already vulnerable is not a defense. It is often the reason the injury is as bad as it is.
What decides these cases is the baseline. The question the adjuster, the defense doctor and eventually the jury will ask is: what was this person’s back like in the six to twelve months before the crash, and what is it like now? If you had a lumbar strain in 2021, finished treatment, went back to full duty at a Chatsworth warehouse, and hadn’t seen a doctor for your back in three years, the baseline is a working back. A crash on the 405 that leaves you with radiating leg pain and an MRI showing a new disc extrusion at L5-S1 is a new injury on that baseline, and the prior strain is nearly irrelevant. If, on the other hand, you were in active treatment for the same back the month before the crash, the question becomes how much worse it got, and that requires careful medical work to separate the two.
Can I make a claim if I had a back injury before the accident?
Yes. California allows recovery for the aggravation of a pre-existing injury or condition. The at-fault driver is liable for the difference between your condition before the crash and your condition after, and for the full extent of that difference even if a healthier person would have been hurt less. The case is proven by documenting your function before the crash, the new symptoms and findings after it, and a treating physician’s opinion tying the change to the collision.
How California handles pre-existing conditions
Two principles work together. The first is aggravation: a defendant who worsens an existing condition pays for the worsening. The second is sometimes called the eggshell plaintiff rule: a defendant takes the injured person as they find them, so a plaintiff whose prior injury made them more susceptible still recovers for the full harm the crash caused. The defendant does not get a discount because you were easier to hurt.
The practical limit is apportionment. Where the evidence allows a doctor to separate what the crash caused from what was already there, the award covers only the crash’s share. Where it can’t reasonably be separated, California does not require the plaintiff to do the impossible, and the defendant bears the uncertainty they created. This is where the quality of the medical opinion matters. A treating orthopedist or physiatrist who has read the prior records and can explain why the new findings are new, and why the prior condition was stable, is the center of the case.
Filing a claim puts your back at issue and waives the physician-patient privilege for that body part and for a reasonable time before the crash. It does not open your whole medical history. The defense will ask for ten years of everything; what they are entitled to is the records relevant to the injured area over a reasonable period.
What the insurance company will argue
The adjuster will find the prior injury, sometimes from your own health insurance records, sometimes from a prior claim in the industry database, and build the file around it. The arguments are familiar: “pre-existing degenerative condition,” “no new injury,” “would have had this pain anyway.” If your MRI shows degenerative disc disease, they will say the crash didn’t cause it, which is true and beside the point. Degenerative changes are present in most adults over 40, most of whom have no symptoms. The claim is for the symptoms the crash produced, not the anatomy you were born with.
A Northridge client in her fifties had been treated by a chiropractor for low back pain on and off for years. She was rear ended on Nordhoff by a delivery van and developed leg pain and numbness she’d never had. The insurer offered an amount that treated her as a chronic back patient with a sore week. The prior chiropractic records actually helped: they showed years of axial back pain with no radicular symptoms, no leg complaints, no imaging. The post-crash MRI showed a herniation compressing the S1 nerve root, matching the leg symptoms. The before and after were different injuries, and the records proved it.
What to do now
Tell your attorney and your treating doctor about the prior injury at the first meeting. Hiding it is the one thing that can actually sink the case, because the defense will find it and the question will no longer be about your back. Get your prior records yourself so they can be reviewed before anyone else sees them. Make sure your current provider documents the prior history and states a clear opinion on what changed. “Aggravation of pre-existing lumbar condition with new radiculopathy” is a sentence that carries a claim.
Then document your baseline from outside the medical records. Work duties, gym attendance, a hiking app, photos from a trip in the months before the crash, a supervisor who can describe your performance. The defense will say you were already limited. The people and records who knew you before the crash say otherwise.
Common mistakes
Denying the prior injury on an intake form or in a deposition is the worst mistake and it is not recoverable. Treating with the same chiropractor who saw you for the old injury without getting an orthopedic evaluation leaves the record vague about what is new. Letting gaps open in current treatment hands the insurer a second argument. Describing your pain as “the same as before, just worse” to a provider, when in fact the symptoms are different, understates the injury in the record that matters most. And accepting an early offer that prices the claim as a flare-up, before imaging and a causation opinion are in the file, locks in the insurer’s version of the medicine.
Questions people ask next
Will the insurance company see my old medical records? Yes, for the injured body part over a reasonable period. They are not entitled to unrelated records or your whole history.
What if my MRI shows degeneration as well as a herniation? Degeneration is common and usually symptom free. The claim is for the symptoms and findings that appeared after the crash.
Does a prior workers’ comp back claim affect my car accident case? It becomes part of the baseline. If you had recovered and returned to work, it shows the back was functioning before the crash.
Manoukian Law Firm handles car accident cases throughout Los Angeles County, including many where the client had a prior back or neck injury, and Vaheh Manoukian personally works with the treating physicians on the before-and-after question. If you were hurt in a crash and worried about your history, call (818) 818-5031 for a free consultation.
