Treatment of habitual patellar dislocation

Many people do not understand why medicine likes to use the word "habitual" to describe diseases. In fact, as the name suggests, habitual means that it will occur frequently and for a long time. Habitual patellar dislocation means that the patella often dislocates. At this time, conservative treatment can no longer cure it, and everyone needs to undergo surgical treatment.

Even without obvious trauma to the knee joint, dislocation can occur by squatting or strong contraction of the quadriceps. When the patient flexes the knee, the patella dislocates to the outside of the lateral femoral condyle and can be naturally restored when the knee is extended.

Physical examination shows poor development of the quadriceps, often accompanied by external rotation of the calf or genu valgum. The patella is underdeveloped and the knee cannot extend. The patella may be in a normal position when the knee is extended, but may slowly move outward or even dislocate when the knee is flexed, and the dislocation is most obvious in the squatting position. If force is applied to resist the lateral displacement of the patella, knee flexion will be limited.

treat

Habitual patellar dislocation generally requires surgical treatment. Depending on the cause, different comprehensive surgical methods are adopted. The general principle is that for patients with immature epiphyses, soft tissue surgery is the main option. For patients with mature epiphyses, bone surgery may be considered.

The most basic surgery is to completely release the lateral contracture tissue of the patella. Then, depending on the specific situation, two or three surgical methods are selected to adjust the force line of the knee extensor mechanism or reconstruct the medial patellofemoral ligament.

1. Soft tissue surgery

(1) Tightening and suturing of the medial patellar retinaculum and medial patellofemoral ligament can be performed under arthroscopy.

(2) Inferior and medial quadriceps head transposition.

(3) Upward transposition of the lateral head of the quadriceps femoris.

2. Patellar ligament transfer

The lateral half of the lower end of the patellar ligament was cut and flipped inward and sutured.

3. Tibial tubercle transposition

The tibial tuberosity is dissected and displaced medially and anteriorly.

4. Osteotomy

For patients with significant femoral rotation and genu valgum, osteotomy correction may be considered.

5. Patellofemoral arthroplasty

Reshape the patella, raise the lateral condyle of the femoral trochlea, and deepen the femoral trochlear groove.

6. Medial patellofemoral ligament reconstruction

Reconstruction of loose or ruptured medial patellofemoral ligament using other tendinous tissue.

This type of disease can be treated more effectively with surgery, but at the same time, attention should be paid to whether this type of disease brings complications to the patient. This disease is accompanied by abnormal development of the knee joint. Surgery can only solve dislocation, but cannot restore normal patellar alignment, so other methods are needed to reduce it.