Dislocation of patella
Dislocation of the patella refers to that during exercise, the patella is detached from the normal part of the knee joint and slips to the outside of the external femoral condyle; It is caused by sports injury, and is mainly seen in teenagers; It turns into knee joint pain, swelling and movement obstruction;
1、 Etiology. The normal patella is located in the front of the distal femur, and the articular cartilage is behind the patella, forming a patellofemoral joint with the femoral pulley. When the knee joint is subjected to direct or indirect violence, it is easy to cause the patella to come out of the femoral trochlear, thus causing patellar dislocation. The specific reasons include congenital factors and acquired factors.
① Congenital factors. Congenital ligament relaxation will lead to greater flexibility of the patella, which is prone to dislocation during exercise, or the patella and femoral pulley are relatively shallow, which is also prone to patellar dislocation.
② Acquired factors. In the process of strenuous exercise, if the trajectory of patella and femur does not match perfectly, patellar dislocation may occur.
2、 Symptoms. Patients with patellar dislocation mainly show weakness, swelling, pain, difficulty in movement, etc. of the knee joint, and some patients may also be accompanied by ligament injury, intra-articular hemorrhage, osteochondral fracture and other symptoms.
3、 Treatment. Patients with patellar dislocation should go to the emergency department, orthopedics department or sports medicine department for medical treatment in time. Generally, most patellar dislocations are transient and can be reset automatically. For example, patellar dislocations occur in the process of knee flexion, and patella will be reset in the process of knee extension; If the patella is still dislocated at the time of treatment, the patient can take manual reduction or surgical reduction.
