Dislocation of the kneecap / patellar dislocation

We distinguish between traumatic patellar dislocation, which often occurs only once, and habitual patellar dislocation, which is usually congenital.

In traumatic patellar dislocation, the kneecap is displaced outwards, particularly in the event of twisting trauma. The snapping back of the kneecap regularly leads to a second "snapping sensation". As the quadriceps muscle can no longer stabilize the knee in a fresh patellar dislocation, a patellar dislocation regularly leads to a fall. The initial dislocation usually results in a haematoma in the joint (haemarthrosis).

Minor subluxations of the kneecap, i.e. tilting of the kneecap to the edge of the sliding bearing and one-off, traumatic patellar dislocations can be treated conservatively. This includes physiotherapy with strengthening of the vastus medialis muscle, which centers the kneecap. In addition, special knee orthoses are often prescribed, which also stabilize the kneecap during the initial scarring phase.

Habitual patellar dislocation usually leads to pronounced wear/arthritis of the patellar cartilage (retropatellar arthrosis). It must therefore generally be treated surgically. If the retaining ligaments are only slightly overstretched, it is possible to separate the capsule on the outside(lateral release) in combination with internal tightening of the retaining ligaments of the kneecap(medial ligament tightening). In the case of chronic patellar dislocation, however, a replacement of the patellar ligaments(MPFL plastic surgery) is preferred today.