"They say it's not work-related."

The standard, precisely

For a physical injury, § 3600(a)(3) requires the injury be "proximately caused by the employment, either with or without negligence." A contributing cause is enough.

Where a psychiatric injury is claimed on its own, the standard is higher — § 3208.3(b) requires that actual employment events were "predominant as to all causes combined." Except where the worker was the victim of a violent act, where it drops to "a substantial cause — at least 35 to 40 percent." More.

These two standards get conflated constantly, including by people who should know better. A physical injury claim is not governed by the psychiatric standard.

The four arguments you will get

"It's degenerative." Degeneration is near-universal and mostly asymptomatic. The question is what caused the disability, not what appears on an image. How that argument is answered.

"There's no incident." There does not have to be. Cumulative trauma is a recognized claim, and under § 5412 the date of injury is when you first suffered disability and knew it was work-related — not when the wear began. How.

"You had a prior injury." This argument has teeth — under Lindh, a pre-existing condition that never disabled you can still support apportionment. What the defense has to prove is that it caused part of this disability, on substantial medical evidence; pointing at your history is not that proof. And a prior disability may open a SIBTF claim — money in addition to what your employer owes. More.

"You didn't report it right away." § 5402(a) makes knowledge by any supervisor or person in authority, from any source, equivalent to notice — and § 5403 provides that late notice does not bar a claim unless the employer was actually prejudiced. More.

What actually resolves it

A medical-legal evaluation — a QME or AME — resolves causation disputes. How.

And what wins it is the record, not the argument:

The mechanism, described specifically — what you were doing, with what, how much, how often, for how long.

Contemporaneous documentation — a text, an incident report, a first-aid log, a message to a supervisor.

Your pre-injury records showing no prior complaint. The absence of complaint is affirmative evidence.

Your actual job duties, in writing, with weights and frequencies.

And in an exposure case, the Safety Data Sheets, air monitoring, and hearing conservation audiograms your employer is required to maintain — exposure records for 30 years. More.

Two things that keep running

§ 5402(c): the employer must authorize up to $10,000 in medical treatment from the day the claim form is filed until liability is accepted or rejected.

§ 5402(b): if liability was not rejected within 90 days of your claim form, the injury is presumed compensable — and that presumption can only be rebutted by evidence discovered after the 90 days ran out.

How denials work and what to do about them.