Patient question
ACL tear or MCL tear: what is the difference, and which one do I have?
Dr. Pablo GelberOrthopaedic Knee Surgeon
Quick answer
An ACL tear usually comes from a twist or sudden stop, with a pop, fast swelling and later looseness. An MCL tear usually follows a blow to the outer knee and hurts on the inside edge. Most MCL tears heal with a brace; many ACL tears in active people need reconstruction, explains Doha knee surgeon Dr. Pablo Gelber.
Two different ligaments, two different jobs
The anterior cruciate ligament (ACL) sits in the centre of the knee and stops the shin bone sliding forwards and rotating. The medial collateral ligament (MCL) runs down the inner side of the knee and resists the knee being pushed inwards.
The MCL has a good blood supply and usually heals on its own. The ACL sits inside the joint fluid and, once fully torn, does not usually heal back to its normal strength.
ACL and MCL tears side by side
- How it happens: ACL from a twist, landing or sudden change of direction; MCL from a blow to the outer knee or the knee buckling inwards
- What you feel: ACL often a pop deep inside; MCL a tearing or sharp pain along the inner edge
- Swelling: ACL usually swells within hours; MCL swelling is often milder and more localised
- Later on: ACL tends to give way when turning; MCL is tender on the inside but often stable once it heals
- Usual treatment: ACL rehabilitation or reconstruction depending on your goals; MCL a hinged brace and physiotherapy for most grades
- Return to sport: MCL often weeks to a few months; ACL after reconstruction usually around 9 to 12 months
When both are torn together
In football, padel and basketball the ACL and MCL are often injured in the same moment. In many patients the MCL is allowed to heal in a brace first, then the ACL is reconstructed once the knee moves well. Higher-grade MCL injuries with an ACL tear sometimes need both treated surgically. That decision depends on examination and MRI.
When to see a knee surgeon in Doha
Book an assessment if your knee swelled quickly after a twist, if it feels loose or gives way, or if inner knee pain has not eased after two to three weeks. Seek urgent care if the knee is badly deformed, you cannot put any weight on it, or your foot becomes numb or cold. At Aman Hospital, Dr. Gelber examines both ligaments, compares the knee with the other side and arranges an MRI when it will change the plan.
Frequently asked questions
Can I walk normally with an ACL or MCL tear?
Often yes, after the first few days. Walking well does not rule out a torn ACL, because the knee usually gives way only when you turn or pivot.
Will an MRI tell me which ligament is torn?
Usually, yes. The MRI is read together with the examination, which shows how loose the knee actually is and helps decide the treatment.
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