What causes a patellar dislocation?
A patellar dislocation may be due to direct trauma to your patella or twisting of your knee. Along with the patellar dislocation, the injury may also result in the fracture of the patella, tibia, or femur simultaneously.
The patella, commonly known as the kneecap, is one of the four bones (femur, tibia, fibula, and patella) that make your knee joint. When it slips out of the knee joint, the condition is known as a patellar dislocation.
Patellar dislocations are common, particularly in adolescent females and athletes. Having a structural abnormality in the patella puts you at a high risk of patellar dislocations.
A patellar dislocation may be due to direct trauma to your patella or twisting of your knee. Along with the patellar dislocation, the injury may also result in the fracture of the patella, tibia, or femur simultaneously.
If you get a patellar dislocation, you would not be able to extend your knee, walking might feel painful and fluid might get filled in your knee, which can be observed as swelling.
How is a patellar dislocation diagnosed?
- A patellar dislocation can be usually diagnosed by just looking at your knee joint. Your doctor might gently press on your knee joint and feel the dislocated patella.
- Your doctor may ask for an X-ray of your knee joint to check if there are any fractures.
- He may also ask for a magnetic resonance imaging (MRI) of the knee joint if he suspects damage to the surrounding cartilage or tear of the ligament.
What is the reduction of a patellar dislocation?
The reduction of patellar dislocation is a simple and safe procedure that aligns the patella correctly in the knee joint and restores it to its normal position. If not associated with fractures, it can be performed manually.
Painkillers are usually not required before the reduction procedure. If you get anxious, your doctor might sedate you or give local anesthesia to numb your knee.
- Reduction of patellar dislocation is performed in the following way:
- Your doctor will cradle your affected leg in one of his/her arms.
- He will then slightly flex your hip to relax the quadriceps muscle located in front of your thigh.
- Next, he will gently extend your lower leg that will spontaneously align the patella correctly.
When does your doctor recommend against the reduction of patellar dislocation?
Your doctor will not perform a reduction of a patellar dislocation if there is an associated fracture of the tibia or fibula. If you face recurrent dislocations, your doctor may prefer surgery over reduction.
What is done after the reduction of patellar dislocation?
- Your doctor will examine your knee physically to check if the reduction has been successful. An X-ray of the knee joint will be ordered to confirm whether your dislocated patella has been restored correctly.
- Next, your knee will be immediately wrapped in a brace, cast, or splint for approximately three to four weeks, or you may need to use crutches for a few weeks.
- You will need to follow-up with your doctor as advised.
- After reduction, recovery from the patellar dislocation usually takes approximately six to eight weeks. With the help of a physical therapist, you can learn some exercises to strengthen the muscles around your knee and thigh that will fasten your recovery.