ACL Tear Symptoms: Signs, Treatment And When Surgery Is Needed You twist your knee while playing football, running, or even stepping off a curb. You hear a "pop." Your knee swells and feels weak. Some people assume the injury will improve without treatment. But these could be ACL tear https://app.notion.com/p/ACL-Tear-Symptoms-When-Do-You-Need-Surgery-40ac824dcdb380e680bec2ec86252cf7?source=copy_link