The dislocation of the patella is a fairly frequent accident. It occurs most often in adolescents or young people. But unfortunately also sometimes later ...
The patella (also called patula) is that little bone that is part of the knee joint. It is a round, puck-shaped bone located in front of the knee. The patella is fixed down on the tibia bone by the patellar tendon. And up to the quadriceps muscle.
The dislocation of the patella often occurs after a relatively slight trauma, the patella out of its place that it usually occupies in the knee joint (at the bottom of the femur - the trochlea).
The patella can be dislocated in a more or less complete ... Clearly, the patella can move out of its usual situation and stay there. Other times, she can dislocate herself, then return to her place either spontaneously or by helping him (by extending the leg, and sometimes by pushing the patella). At other times, the person complains of a patellar instability (the kneecap goes out, then resumes spontaneously by mobilizing his knee, walking ...).
One thing is certain: after a dislocation, it will be necessary to put the knee at rest!
Except in quite exceptional cases, one can rarely incriminate a traumatism of the knee in the dislocation of the patella. Okay, the patella can not luxate spontaneously, when the person remains motionless or walking quietly. But still quite often, it is only a modest impact on the knee that causes this dislocation. Which means that there is indeed a fragility at this level that facilitates this dislocation.
Among the causes, or rather the contributing factors, of the dislocation of the patella: ligamentous hyperlaxity (more common in women), a high patella situated, bone structures (flat patella, groove of the femur slightly dug). In short, the constitution of certain ligaments of the knee, the shape of the patella and its initial position, the appearance of the femur ... are involved in patellar dislocation. In medical terms, we speak of dysplasia, as if there was a knee manufacturing defect.
The role of the medial patellofemoral ligament is more and more implicated in the dislocation of the patella. In fact, during a first dislocation, the more or less important lesion of this ligament would then favor problems of instability of the patella.
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