ACL or Meniscus Tear? How to Tell the Difference

An ACL tear and a meniscus tear can feel almost identical in the moment... a twist, a pain, a swollen knee, and people mix them up all the time. But there are a handful of clues that tell them apart, and one of them is a bigger giveaway than all the rest. This is part of my series on ACL injuries. In this video I walk you through how to tell an ACL tear and a meniscus tear apart, clue by clue, and what to do if you think it might be one of them. The first clue is how it happened. An ACL tear is usually a faster, more violent movement, a sudden change of direction, a pivot, or an awkward landing. A meniscus tear often comes from a twist on a bent knee, like turning while squatting, and in older people it can tear with very little force at all. The second clue, and the biggest giveaway, is how fast the knee swelled: an ACL tends to balloon up within a few hours because it bleeds into the joint, whereas a meniscus usually swells more slowly, creeping in overnight or over a day or two. The third clue is what the knee does afterwards. An ACL tear gives you instability, that “I can’t trust it” feeling of the knee giving way when you turn. A meniscus tear is more mechanical, catching, clicking, or even locking so you can’t fully straighten it. And the fourth clue is where the pain sits... a meniscus often gives sharp, pinpoint pain right on the joint line, while ACL pain is deeper and more about that unstable feeling through the whole knee. There’s an important twist, though: these two injuries very often happen together. The same movement that tears your ACL can tear the meniscus at the same time, so it isn’t always an either/or. That’s exactly why these clues are a guide to understand what’s going on, not a substitute for getting it properly assessed. The only way to know for certain is a hands-on assessment and usually an MRI, which shows clearly what’s torn and whether it’s one or both. In the next video I’ll explain what that pop you feel when you injure your knee actually means, because it’s not always the ACL, and it tells you more than you’d think. Make sure you’re subscribed so you don’t miss it. And if you’re not sure which one you’ve done, drop a comment with what happened and how the knee’s behaving, I’ll point you in the right direction. Joe ------------------------------------- Book a Free Discovery Call: https://sharpphysiotherapy.co.uk/free... Find Your Nearest Clinic: Doncaster | Lincoln | Newark Welcome to Sharp Physiotherapy, we specialise in keeping people active, pain-free, and away from medication. This video is for educational purposes only and not a substitute for medical advice. If you're dealing with pain, book a free call with our team to find out what’s going on. Check out our website at...https://www.sharpphysiotherapy.co.uk Follow Our Socials... Instagram:   / sharp_physio   TikTok:   / sharp_physiotherapy   Facebook:   / jsphysio1   © Sharp Physiotherapy {{2025}}. All rights reserved. Chapters 0:00 Introduction – ACL vs Meniscus Tears 0:24 Meet Joe – Ex-Pro Football Physiotherapist 0:33 Clue 1: How the Injury Happened 1:06 Why Meniscus Tears Happen More Easily in Older Adults 1:26 Clue 2: Speed of Swelling (The Biggest Giveaway) 2:18 Clue 3: What the Knee Does Afterwards 2:51 Bucket Handle Tears & Knee Locking 3:17 Clue 4: Location of the Pain 3:57 Why ACL and Meniscus Tears Often Happen Together 4:21 Getting a Proper Diagnosis (Physio Assessment & MRI) 4:43 What's Next – The Truth About the "Pop" Sound