“They Say It Was Already There!” | WSIB Blamed a Pre-Existing Condition? What the Rules Actually Say

An older man in a knee brace sorts through stacks of medical records at his dining table with a cane beside him.

Many people have an old back problem, a worn knee or a past injury. If the WSIB points to yours, it can feel like your claim is over. It is not. The rules are more protective than most people expect.

Can the WSIB deny my claim because of an old condition?

No. The WSIB's policy on pre-existing conditions says entitlement for a work-related injury or disease "will not be denied due to the existence of a pre-existing condition." The policy applies to all decisions made on or after 1 November 2014.

So where does an old condition matter?

Later, when the WSIB looks at your ongoing impairment. The question becomes whether the work injury is still a significant contributing factor to how you are now.

The policy compares the work injury with the old condition. If the work injury alone would have caused a similar level of impairment, it still counts as significant.

What does aggravation mean?

An aggravation is when a work injury makes an existing condition worse. The policy says benefits for an aggravation continue until you recover from the aggravation, meaning until you are back to how you were before the work injury.

That is why the most important evidence is about how you were before.

What evidence helps?

  • Your life before the injury. Full duties at work, no time off, no restrictions, the sports or tasks you did without trouble.
  • Your medical history. Gaps in treatment for the old condition, or records showing it was stable.
  • The change. Your first medical notes after the work injury, and how they differ from earlier ones.
  • A clear opinion. A doctor or specialist who addresses whether the work injury is a significant contributing factor, using those words.
  • Your own record. A dated log of symptoms and what you can and cannot do, from the start.

Why use Hurt Square?

Because the most important evidence is how you were before the injury, and how that changed. Hurt Square guides give you one place to show the change, with dates.

  • The change, on the record. The National Workplace Injury Recovery Guide has structured space for your symptoms, what you can and cannot do, and every appointment from the day you were hurt. That dated log is what the significant contributing factor question turns on.
  • The Ontario rules, in plain words. The Ontario Workplace Injury Companion Guide explains Forms 6, 7 and 8 and how to object, step by step through to the Appeals Tribunal.
  • Made for hard days. 123 pages and more than 1,200 fillable fields that work on your phone, tablet or computer, in plain language. When your union representative, worker adviser or lawyer asks for something, it is already there.

Both guides, $39 until 22 November. The National Workplace Injury Recovery Guide and the Ontario Workplace Injury Companion Guide, with the discount applied at checkout. Bought separately: $63.99.

Get both guides

What if a decision says my problems are now from the old condition?

You can object, usually within six months, under section 120 of the Workplace Safety and Insurance Act. The deadline printed on your decision letter is the one that applies. New medical information that speaks to the significant contributing factor test is what most often changes these decisions. Our article “WSIB Rejected My Claim!” | WSIB Denied Your Claim? Your Next Steps Before the Deadline explains the first steps.

Who can help?

The Office of the Worker Adviser, if you are not in a union. It is an independent agency of the Ontario government, and its service to non-unionized injured workers is free. Its number for English service is 1-800-435-8980. If you are in a union, start with your union representative. A community legal clinic is another free route.

Read next

National Workplace Injury Recovery Guide

If your recovery were reviewed tomorrow, what would your record say?

The National Workplace Injury Recovery Guide is where your recovery gets documented, day by day. Symptoms, appointments, calls and costs, written while they are fresh. It works in every province and it stands on its own.

Both guides, $39 until 22 November. Add the Ontario Workplace Injury Companion Guide for the dates and rules that shape your recovery in Ontario, and the discount applies at checkout. Bought separately: $63.99.

Every figure in this article comes from a named source. How we check
Last verified: October 2026.
Workplace Claim Correspondence Tracker: Free Starter Edition

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Workplace Claim Correspondence Tracker: Free Starter Edition

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Free for your wallet: a printable card that tells you what to do first if you are hurt at work and what to write down.

Everything above is free.

If you want the whole system, it comes in two parts.

Two things decide how an injury claim goes.

What you wrote down. The National Recovery Guide is the daily record: symptoms, appointments, calls, costs, and what you can no longer do. It is the part a claim is eventually judged on.
Whether you did the right thing at the right time for where you live. Your Provincial Companion Guide carries your deadlines, your forms, your boards and your appeal routes. Ontario is not British Columbia. Generic advice sends people to the wrong form, and then to the wrong date.

Buy only the National Guide and you keep a perfect record, then miss a deadline nobody told you about.

Buy only your Provincial Guide and you know every date, with nothing written down to send.

You need both. That is why they are priced as a pair.

Bought separately: $63.99. Together: $39 until 22 November.

The discount applies automatically at checkout.

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Hurt in a vehicle instead? Start here. ·  Not sure which province edition you need? Find yours.

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Your Recovery. Documented. Protected.

You are not the only one

Somebody else has already had this exact week.

We closed comments on our articles, on purpose. A public comment box under a page about claims is a place where people give away details that can be used against them later, and we would rather not build that.

The Square is where that conversation belongs instead. Canadians hurt in an accident or on the job say what happened, read what happened to everyone else, and find out they were never the only one. Post under your name or not at all.

Say what happened, in The Square

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Moderated, with house rules. Please leave out claim numbers, adjuster names and anything else that identifies your file. Something specific to your own claim is better sent to recovery@hurtsquare.ca.