Dislocating your kneecap can be painful and overwhelming, but knowing what to expect with your diagnosis and treatment can help ease your nerves as you aim to get back on your feet. A patellar (kneecap) dislocation is a common sports injury seen by knee specialists at The Ohio State University Wexner Medical Center in Columbus, Ohio. When you have a dislocation, you’ll want to be evaluated by an orthopedic expert to determine if there’s other damage to the knee and ensure that you receive proper care to prevent complications.
What is a kneecap dislocation?
Patellar dislocation happens when the round-shaped bone (the patella, or kneecap) covering your knee slides out of place. It usually occurs when there’s a sudden change of motion and your leg is already planted, most often while playing a sport like basketball or soccer. A dislocated kneecap can also result from a direct hit.
While you might be able to “pop” the kneecap back in place after the injury, it’s highly recommended you wait to have a medical professional do this. Your doctor will also need to examine you and take X-rays to check for broken bones or other damage. Magnetic resonance imaging (MRI) is also recommended in most cases to assess cartilage damage.
What’s the difference between a patellar dislocation and knee dislocation?
A knee dislocation is a traumatic injury often requiring advanced, emergency intervention. During a knee dislocation, the thighbone (femur) or shinbone (tibia) disconnects from the knee joint, resulting in damage to multiple ligaments and other areas of the knee. While rare, this type of orthopedic trauma needs immediate attention from expert knee surgeons to prevent further damage and produce the best outcomes. The Ohio State Wexner Medical Center is specially equipped to manage the complex and coordinated care needed to treat an injury like a dislocated knee.
Kneecap dislocation, on the other hand, is a more common sports injury that can usually be treated with rest, bracing and physical therapy.
Causes of a kneecap dislocation
Dislocating your kneecap usually happens for one of three reasons, including:
- A sudden change in motion while the leg is planted
- A direct hit or sudden blow to the knee
- Chronic knee issues
Because of their anatomy or activity level, some people are more prone to dislocating their kneecap. These risk factors include:
- Playing sports where cutting motions are frequent (soccer or basketball, for example).
- Playing sports with heavy physical contact (football).
- Having a kneecap that sits higher than normal (patella alta).
- A condition where the groove in which the kneecap moves is shallower than normal (trochlear dysplasia).
What are the symptoms of a kneecap dislocation?
The most common symptom of a dislocated kneecap is that the bone visually looks out of place. Other symptoms may include:
- A popping noise at the point of impact
- Knee pain or tenderness
- Instability or feeling as if your knee might give out
- Swelling
- Bruising
- Buckling at your knee
- Locking at the knee
- Inability to walk
Diagnosing a kneecap dislocation
If you suspect you’ve dislocated your knee, it’s important to seek medical attention even if the bone pops back into place on its own. Your doctor can usually diagnose a kneecap dislocation through a physical exam, but they’ll most likely want to perform further imaging and other testing to make sure you haven’t damaged other parts of the knee or leg. We might recommend one or more of the following diagnostic tools:
- X-rays
- MRI
- Computed tomography (CT) scans
Sometimes a dislocated kneecap will correct itself without you realizing it was ever dislocated. You’ll notice only symptoms of pain and swelling. Imaging can show evidence of a dislocation and help us provide an accurate diagnosis for your knee pain and determine whether you might be a candidate for surgical treatment.
How is a dislocated kneecap treated?
Most of the time, a first-time kneecap dislocation can be treated using conservative, nonsurgical treatment methods. Depending on the severity of your injury, how many times your kneecap has dislocated, and whether you damaged other parts of your knee, you may need surgery.
The knee team with Ohio State Sports Medicine is made up of highly specialized orthopedic surgeons, physicians and physical therapists that bring advanced treatments and innovative recovery approaches. As the trusted team physicians for Ohio State Athletics and professional and Olympic athletes across the nation, we make this same elite level of care accessible to everyone.
Nonsurgical treatments
Your doctor may recommend one or more of the following to treat your kneecap dislocation:
- Reduction – To relocate, or pop, your kneecap back in place, we’ll gently push the bone into its normal position using a technique called reduction. Sometimes a mild pain reliever or sedative is given before the procedure.
- Bracing – Specialized braces are available to help stabilize the knee and prevent dislocation from happening again.
- Physical therapy – Specific exercises and techniques can be used to strengthen the muscles around the knee to keep the kneecap in proper alignment. This can also help prevent future kneecap dislocations.
Throughout your recovery, you may also use nonsteroidal anti-inflammatory medications (ibuprofen or naproxen) for pain relief. Other treatment methods could include activity modification, ice and compression.
Surgical knee dislocation treatments
If other parts of your knee are damaged, or if you have multiple kneecap dislocations, then you may need a surgical repair. Knee surgery for patellar instability can include the following:
- Arthroscopy
- Medial patellofemoral ligament (MPFL) reconstruction, or the rebuilding of other ligaments that hold the kneecap in place.
- Kneecap realignment surgeries, such as tibia tubercle osteotomy.
- Trochleoplasty and other procedures that deepen the groove in which the kneecap moves.
At Ohio State, we have experts in all types of surgery for patellar dislocations, and they can determine which option is best for your unique situation. If your entire knee is dislocated, you’ll need complex knee surgery, possibly multiple surgeries, to treat your condition.
How long does it take to recover from a kneecap dislocation?
Recovery time for a dislocated kneecap will vary, depending on other underlying knee conditions, extent of the damage and other factors, but generally people return to normal activity in roughly six to eight weeks. It’s usually several months before you’re able to participate in sports again.
If you need knee surgery, recovery time will be longer. It’s important to listen to your doctors on when it’s appropriate to return to activity to prevent further injury.
A knee dislocation will, of course, require much more time to recover. Most people need at least a year.
How can I prevent kneecap dislocations?
While a dislocated kneecap isn’t entirely preventable, especially if you play contact sports, there are steps you can take to reduce your risk, including:
- Use proper techniques for your sport
- Practice exercises that strengthen and condition your legs
- Follow physical therapy recommendations following a first kneecap dislocation