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A dislocated kneecap

When the kneecap dislocates, it usually moves to the outside of the knee. This often happens after a twist, misstep or sports injury and is particularly common in young people. The knee immediately becomes very painful, may look visibly deformed and can swell quickly. Do not try to push the kneecap back yourself. Assessment must also check for nerve and blood vessel problems and damage to bone and cartilage, such as an osteochondral injury.

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  • In a patellar dislocation, the kneecap slips out of its normal track, usually towards the outside of the knee.
  • The knee is often immediately very painful and you usually cannot continue walking normally.
  • The kneecap may visibly sit to one side, but sometimes slips back spontaneously.
  • Do not try to put the kneecap back yourself.
  • After a dislocation, cartilage or bone damage and nerve or blood vessel problems must also be considered.

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D
Dislocated elbowIn a dislocated elbow, the bones forming the joint are no longer in their normal positions. This is painful and can damage blood vessels, nerves, ligaments or bone. Keep the arm still, never try to put the elbow back yourself and have the injury assessed urgently the same day.
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