Most sports injuries are explained by the moment they happen. The cut, the landing, the collision, the replayed frame where everything goes wrong.
But that moment rarely tells the full story.
Injury is better understood through the lens of active errors and latent errors. This distinction explains not just how an injury occurred, but why it occurred at that time.
An Example Outside of Sport
In medicine, a patient might receive the wrong medication.
The active error is obvious, the nurse administers the wrong drug.
But investigations don’t stop there. They look upstream at latent errors:
- Similar packaging between medications
- Fatigue from long shifts
- Understaffing
- A verification system that failed long before the injection
The medication error happened in seconds.
The conditions that allowed it built up over weeks or months.
Fixing the final action alone doesn’t make the system safer. Fixing the upstream conditions does.
Now Apply This to ACL Injuries
ACL tears are often explained the same way medication errors are, by focusing on the final action.
The athlete plants, the knee collapses inward, the trunk shifts, sometimes there’s contact, and the ligament fails.
That is the active error. It describes the mechanism, and it’s useful, but it’s incomplete.
If the mechanism were the cause, the injury would happen every time that movement appeared. But athletes cut, decelerate, and land in similar positions hundreds of times without tearing their ACL.
So the more important question is this: Why did the ACL fail on this rep and not the hundreds before it?
The Latent Errors Behind the Tear
This is where the explanation moves upstream.
Before the injury:
- Was the athlete carrying residual fatigue from a congested competition schedule?
- Had eccentric or deceleration capacity dropped relative to game demands?
- Was cumulative workload exceeding tissue tolerance?
- Were movement options reduced late in the game or late in the season?
- Was force absorption compromised under speed and chaos?
None of these show up clearly on video. But all of them change how force is managed at the knee.
The ligament didn’t fail because of one bad cut. The cut was simply the final exposure.
Why This Distinction Matters
When we focus only on the active error, we end up chasing technique in ideal conditions. We cue better positions in warm-ups and controlled drills, then act surprised when those positions disappear under fatigue, speed, and chaos.
Sport doesn’t happen in ideal conditions, and tissues don’t fail during rehearsed movement. They fail when systems lose margin for error.
Active errors tell you where the injury occurred. Latent errors provide insight and context into why it occurred.
Once you understand that difference, the focus shifts. Instead of replaying the clip repeatedly, the work involves building and maintaining the capacities that keep athletes robust under real-world demands.
That’s where injury risk is actually influenced.
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I hope this helps,
Ramsey
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