You may have:

  • Pain, often sudden and severe
  • A loud pop or snap during the injury
  • Swelling within the first 24 hours after the injury
  • A feeling of looseness in the joint
  • Inability to put weight on the joint without pain, or any weight at all

These injuries need medical attention. In some cases, as with ACL tears, you may need surgery so that your knee will be stable and won’t give out when you twist or pivot.


Your doctor will give you a physical exam. If your knee is very tense and swollen with blood, your doctor may use a needle to drain it. You may need X-rays to make sure you don’t have a broken bone, as well as an MRI to check on any ligament injuries.