"You already had a bad back." It's the most common thing insurers say to injured people over 40, and it's often the reason people assume they don't have a case. In New Jersey, a pre-existing condition doesn't defeat your claim. A defendant who makes an existing condition worse is responsible for that harm. The question is how much worse, and that's a question of evidence.

The rule: aggravation is compensable

New Jersey's Model Civil Jury Charges instruct juries that when a plaintiff had a pre-existing condition, the defendant is responsible for the aggravation or worsening caused by the accident, but not for the condition as it would have been without the accident. A person with a pre-existing condition is entitled to compensation for the additional harm, whether that means more pain, a new herniation, a need for surgery that wasn't needed before, or a shorter time before a condition becomes disabling.

"Take the plaintiff as you find them"

A defendant can't escape responsibility because the injured person was more vulnerable than average. If a crash would have caused a minor injury to a healthy 25-year-old but caused a serious injury to someone with an arthritic spine, the defendant is responsible for the serious injury it actually caused.

Proving aggravation

The plaintiff has the burden of proving what the accident caused, so the evidence matters:

  • Before-and-after medical records: treatment records from before the accident showing how you were doing, compared with records after
  • Comparison imaging: an old MRI next to a new one can show a new herniation, a larger herniation, or new nerve involvement
  • Treating physician testimony explaining the difference
  • Your own history: a period with no treatment before the accident is powerful evidence that the condition was stable
  • Witnesses who saw what you could do before and after

A real example

We recovered the full $1 million combined policy limits for a client whose new disc herniation, after a low-impact rear-end crash, was at the exact spinal level where they'd previously had surgery. The defense argued it was all the old injury. The comparison of the imaging and the medical history showed otherwise.

Be honest about your history

The worst mistake is hiding a prior injury. The defense will get your records, and a prior injury you didn't mention can destroy your credibility. A prior injury you disclosed and explained rarely does. Tell your doctors and your lawyer about prior injuries, accidents, and treatment.

Pre-existing conditions and the verbal threshold

For New Jersey drivers with the limitation-on-lawsuit option, the injury must meet the verbal threshold, usually a permanent injury proven by objective evidence. When there was a prior injury, the treating doctor's certification and testimony should address what's new or worse. This is where comparison imaging becomes crucial.

Pre-existing conditions in workers' comp

In New Jersey workers' compensation, a work accident that aggravates a pre-existing condition can be compensable too. For occupational claims involving a pre-existing condition, the statute sets specific proof requirements (N.J.S.A. 34:15-31). A comp carrier calling an injury "pre-existing" is a reason to get advice, not a reason to give up. What to do if comp is denied.

How insurers use your history

  • Requesting a defense medical exam with a doctor who attributes everything to degeneration
  • Pointing to "degenerative changes" on the MRI, which are present in most adults and don't mean the accident did no harm
  • Seeking years of prior medical records

Each of these can be answered with good evidence and a clear explanation. For more on how injuries are valued, see how much a car accident claim is worth.