Version July 2025
Please read the Disclaimer at the end of this page.
What are discharge instructions? —
Discharge instructions are information about how to take care of yourself after getting medical care in the emergency department ("ED").
What should I know? —
You came to the ED for a knee injury. The doctor thinks you tore your anterior cruciate ligament ("ACL"). This causes swelling and pain in the knee. You might also feel like your knee is unstable or "gives out" when you try to put weight on it.
ACL tears usually happen during sports, when changing directions suddenly or landing from a jump.
Some ACL tears are repaired with surgery once the pain and swelling improve.
You might be waiting on test results. The staff will notify you if there are concerning results.
How do I care for myself at home? —
Ask the doctor or nurse what you should do when you go home. Make sure you understand exactly what you need to do to care for yourself. Ask questions if there is anything you do not understand.
You should also do the following:
●Call your regular doctor and tell them you were in the ED. Make an appointment with a specialist called an "orthopedic surgeon" who repairs ACL injuries.
●Take non-prescription medicines to relieve pain, if needed. Examples include acetaminophen (sample brand name: Tylenol), ibuprofen (sample brand names: Advil, Motrin), and naproxen (sample brand name: Aleve).
●Rest your knee. Avoid movements that worsen pain. Try not to squat or pivot. Avoid climbing stairs if it causes pain or makes your knee feel unstable. You might need to use crutches to help you move around.
●If the doctor gave you a knee brace, wear it as instructed.
●Ice can help with pain and swelling. Put a cold gel pack, bag of ice, or bag of frozen vegetables on your knee every 1 to 2 hours, for 15 minutes each time. Put a thin towel between the ice (or other cold object) and your skin. Use the ice (or other cold object) for at least 6 hours after the injury. It might help to ice longer, even up to 2 days.
●Prop your knee on pillows, keeping it raised above the level of your heart. This can help with pain and swelling.
●Once the pain and swelling improve and your doctor says it's OK, do exercises to help strengthen your knee and get motion back. It's important to do the exercises as instructed to help you recover.
When should I call the doctor? —
Call for advice if:
●The pain or swelling gets worse.
●Your toes are blue, gray, or numb.
●Your knee feels more unstable.
●You cannot put weight on your leg.
●You have new or worsening symptoms.
Patient education: Anterior cruciate ligament tear (The Basics)
Patient education: How to use a knee brace (The Basics)
Patient education: How to use crutches (The Basics)
Patient education: Anterior cruciate ligament injury (Beyond the Basics)
