Treatment of dislocating kneecaps is one of the most challenging and controversial undertakings in orthopedic surgery. The causes of patellofemoral instability [PFI] range from congenital [patients born with dislocated kneecaps] to traumatic [acute injury]. Young females are more commonly affected by this condition than males. Fortunately, approximately two-thirds of patients with one dislocation will do well without surgery. The remaining one-third of patients can have multiple dislocations, in these patients, surgical correction can be considered.

First-time Dislocation

A kneecap dislocation can be a scary and painful event. Often, patients are involved in sports, such as soccer, that involve quick changes in direction. Patients usually describe the event as, “my knee gave out”. In many instances, the kneecap will dislocate and quickly reduce (go back into the joint). As a result, patients are often unsure if their kneecap actually dislocated. There is usually rapid swelling from bleeding into the joint. Kneecap dislocations can mimic other serious knee injuries, such as ACL tears.

Kneecap dislocations are initially treated by reducing the dislocation. In most cases, gently extending [straightening] the knee is all that is required to relieve pain and put the kneecap back in the proper place. A professional should evaluate the knee within a few days of the injury. Sometimes, the dislocating kneecap can break off a piece of bone or cartilage inside the joint. X-rays and, if needed, an MRI can be helpful to diagnose a broken piece of bone or cartilage. It is important to diagnose a bone or cartilage injury because such injuries often need to be repaired surgically within a few weeks of the injury.

As long as there are no associated bone or cartilage injuries, first-time dislocations respond well to RICE [Rest, Ice, Elevation, Compression]. As the acute pain and swelling decrease, moving the knee [range of motion] is encouraged. Exercises to strengthen and retrain the muscles of the core and lower extremity are also very important. Strengthening these muscles helps the knee to maintain a good position during activity. Find out more.

Multiple Dislocations

Unfortunately, about one-third of patients have multiple dislocations despite giving a great effort in physical therapy. Fortunately, there are several surgical stabilization options available. The choice of surgery is based on several factors:

  1. Patient age. If the patient is still growing, we have developed techniques that protect the growth centers of the bone growth plates.
  2. The patient’s unique anatomy that contributes to repeated episodes of dislocation.
  3. The patient’s expectation of activity following surgery.

We have been very successful in achieving our patients’ goals when we take these factors into consideration, as we formulate a treatment plan. We recognize that a “one size fits all” approach to such a complicated problem does not serve the best interests of our patients. Our surgical treatments range from reconstruction of the medial patellofemoral ligament [MPFL] to realignments of the bone osteotomy. Often, we use combinations of these techniques to address as much of the problem as possible.

Congenital Patellar Dislocation

Congenital patellar dislocation (CPD) is a rare condition in which patients a born with a dislocated kneecap. The condition can often run in families. Patients with this condition can be very challenging to treat. They are often otherwise healthy, but have very abnormal knee anatomy. At times, the dislocated kneecap can cause the bones to grow crooked.

Treatment for CPD is almost always surgical. In fact, some experts feel that early restoration more normal kneecap alignment can help the knee to develop more normally. We have a variety of surgical techniques available to correct CPD and preserve future growth. As with the more common forms of PFI, we individualize treatment based on the particular patient.