Torn ACL
A torn ACL is a tear of the anterior cruciate ligament, one of the main ligaments that stabilizes the knee. It usually happens during sports that involve sudden stops, pivots, or awkward landings, often without any contact. Many people report hearing or feeling a "pop" at the moment of injury.
Common symptoms
- A popping sound or sensation at the time of injury
- Rapid swelling within hours
- Pain and difficulty bearing weight
- A feeling that the knee is unstable or "gives way"
- Loss of full range of motion
When to see a specialist
If your knee swelled quickly after an injury or feels unstable, an evaluation is worthwhile, an exam and often an MRI can confirm the diagnosis. Initial care is typically rest, ice, and physical therapy, and not every ACL tear requires surgery. A sports medicine surgeon can help you weigh reconstruction against rehab alone based on your age, activity, and stability.
Treatment options
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Common questions
- Does a torn ACL always need surgery?
- No. A fully torn ACL does not heal on its own, but people with lower-demand lifestyles often do well with physical therapy and activity modification. Surgery is typically recommended for those returning to pivoting sports or with ongoing instability.
- How long until I can play sports again?
- With ACL reconstruction, return to cutting and pivoting sports commonly takes nine to twelve months. Without surgery, timelines depend on rehab progress and whether the knee remains stable.
- Can I walk on a torn ACL?
- Many people can walk once the initial pain and swelling settle, though the knee may feel untrustworthy with quick turns. Walking ability alone does not mean the ligament is intact.
This page provides general information only and is not medical advice. Consult a qualified physician about your specific situation. Listings are not endorsements.