ACL Tear (Knee Ligament)
The anterior cruciate ligament (ACL) is a key stabiliser inside the knee. A tear usually happens during a sudden twist, pivot or landing, and often makes the knee feel unstable.
Causes & risk factors
- Sudden change of direction or pivoting
- Awkward landing from a jump
- Direct blow to the knee (tackles, accidents)
- Sports such as football, kabaddi and basketball
- Sudden stopping or deceleration
Common symptoms
- A loud "pop" at the moment of injury
- Immediate knee pain
- Rapid swelling within hours
- Knee giving way or buckling
- Difficulty bearing weight
- Reduced range of movement
Tests & diagnosis
- MRI
- X-ray
- Clinical ligament examination (Lachman test)
- Knee arthroscopy
Treatment & management
- Rest, ice, compression and elevation early on
- Physiotherapy to restore strength and stability
- A knee brace during recovery
- Arthroscopic ACL reconstruction for active people or persistent instability
- Graded return-to-sport rehabilitation
When to see a doctor urgently
- Knee that repeatedly gives way or feels unstable
- Rapid, tense swelling after a twisting injury
- Inability to straighten or bear weight on the knee
- Locking or catching of the joint
Not a diagnosis. MedDroid gives general educational information about acl tear (knee ligament). It cannot examine you, diagnose or prescribe — always confirm with a qualified doctor.
Frequently asked questions
Do all ACL tears need surgery?
No. Less active people or partial tears may do well with physiotherapy. Surgery is usually advised for young, active people or when the knee stays unstable.
How long is recovery after ACL surgery?
Return to sport typically takes around 9 to 12 months of structured rehabilitation, though everyday activities resume much sooner.
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MedDroid is an AI medical assistant and can make mistakes. It provides general health information, not a diagnosis or medical advice — always consult a qualified clinician. In an emergency, contact your local emergency number immediately.