A<unk>  is a knee injury in which the<unk> (kneecap) slips out of its normal position. Often the knee is partly bent, painful and swollen. The<unk> is also often felt and seen out of place. Complications may include a<unk> fracture or arthritis. A<unk>  typically occurs when the knee is straight and the lower leg is bent outwards when twisting. Occasionally it occurs when the knee is bent and the<unk> is hit. Commonly associated sports include soccer, gymnastics, and ice hockey.<unk> s nearly always occur away from the midline. Diagnosis is typically based on symptoms and supported by X-rays. Reduction is generally done by pushing the<unk> towards the midline while straightening the knee. After reduction the leg is generally splinted in a straight position for a few weeks. This is then followed by physical therapy. Surgery after a first<unk>  is generally of unclear benefit. Surgery may be indicated in those who have broken off a piece of bone within the joint or in which the<unk> has dislocated multiple times.<unk> s occur in about 6 per 100,000 people per year. They make up about 2% of knee injuries. It is most common in those 10 to 17 years old. Rates in males and females are similar. Recurrence after an initial<unk>  occurs in about 30% of people.
Patellar dislocation
Patellar tendon rupture
Patella fracture
Knee dislocation  Knee dislocation  1
Knee dislocation
Acetabular fracture
Hip dislocation
Humerus fracture