Patella Dislocation: Symptoms, Treatment, & Recovery
Patella dislocation is a painful condition that happens when the kneecap is dislodged from the knee joint. Under normal conditions, the patella sits in a vertical groove in the knee joint, called the trochlear groove. When a force is applied to the patella, such as with a fall or collision, the patella can become dislocated from its groove, causing tearing or stretching of the ligaments. Fortunately, patella dislocation is easy to fix and can even resolve on its own.
Types of patella dislocation include:
Congenital patella dislocation – a developmentally caused patella dislocation in which the patella develops outside the trochlear groove.
Acute patella dislocation – patella dislocation caused by force
Patella subluxation – partial dislocation of the patella, which is not as serious as complete dislocation
What Causes Patella Dislocation?
Acute patella dislocation is caused by an external force. Examples of force that may cause acute patella dislocation include:
- A bad step
- A bad fall
- A collision
- A sudden twist of the knee while the foot is planted
Congenital patella dislocation, as the name suggests, is a developmental abnormality and is present from birth.
Patella Dislocation Risk Factors
Risk factors for acute patella dislocation include playing sports in which athletes are required to pivot quickly, or in which athletes are in danger of collision injuries. Dancers are also at risk for these injuries.
Groups of people at risk for patella dislocation:
- Athletes in high-impact sports
- Teenagers who are still growing (while growing, teenagers’ ligaments are looser)
- People with preexisting instability in the kneecap or who have dislocated their kneecap in the past
- Women, due to wider hips putting increased lateral pressure on the knee joint
Risk factors for congenital patella dislocation are not fully understood, though there may be a genetic component.
Symptoms of Patella Dislocation
Symptoms of patella dislocation include the following:
- Immediate swelling of the knee
- Intense pain until the kneecap is put back in place
- Instability of the joint
- Bruising of the knee
- Inability to walk
- Visual deformity of the knee (kneecap visibly out of place)
How is Patella Dislocation Diagnosed?
Your doctor will listen to your symptoms, ask you how the injury occurred, and perform a physical examination. These steps are usually enough to make the dislocation diagnosis. Your doctor will also likely send you for imaging such as MRIs to check for injuries associated with the dislocation, such as torn ligaments or injuries to the cartilage. If your dislocation corrected itself prior to seeing a doctor, imaging tests can confirm that you suffered a dislocation as opposed to another injury.
Treatment for Patella Dislocation
Transient patella dislocations are dislocations that go back into place without intervention. If your patella does not go back into place on its own, your doctor will do it for you. This process of putting the kneecap back in place is called reduction. The sooner this is done, the better. It is done prior to imaging.
After your kneecap is back in the correct position, you may receive imaging to ensure there are no other serious issues that need surgical correction. You may need surgery if you keep suffering patella dislocations, if you have cartilage or other soft tissue damage along with the dislocation, or if you suffer from congenital patellar dislocation.
Patella Dislocation Recovery Time
Recovery from patella dislocation usually requires about six weeks to three months, depending on the severity of the injury. You will likely require a splint to support your knee for several weeks during your recovery, you may need to use a crutch to help you walk, and you may need to complete physical therapy to properly recover.
How Can I Prevent Patella Dislocation?
Prevention of patella dislocation is difficult since it is caused by force injuries. However, there are some things you can do to lessen the likelihood that your patella will dislocate a second time:
- Make sure to complete your rehabilitation, including all of your physical therapy.
- Strengthen the muscles around your knee so that your knee is as stable as possible. Exercises like cycling can help accomplish this.
- Opt for surgical correction if you have a congenital issue that is causing your patella to dislocate.