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TEXT: (908) 224-4639
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Patellar Dislocation

A patellar dislocation, also known as a kneecap dislocation, occurs when the patella (kneecap) moves out of its normal position within the groove of the femur (thigh bone) that it slides along. This displacement disrupts the alignment of the patella with the femur and can lead to pain, instability, and limited movement of the knee joint. Patellar dislocations can vary in severity, ranging from partial dislocations (subluxations) to complete dislocations.

The patella is held in place by ligaments, tendons, and surrounding muscles. A sudden force or twisting motion can cause the patella to dislocate, often moving towards the outer side of the knee joint. Once the patella dislocates, the structures that stabilize it are stretched or damaged, making subsequent dislocations more likely.

Common causes of patellar dislocations include:

  • Sudden Changes in Direction: Activities that involve sudden changes in direction, such as sports that require cutting or pivoting movements, can increase the risk of patellar dislocation.
  • Direct Impact: A direct blow or trauma to the knee can cause the patella to shift out of place.
  • Muscular Imbalance: Weakness or imbalance of the quadriceps and hip muscles, which help stabilize the patella, can contribute to dislocations.
  • Anatomical Factors: Certain anatomical factors, such as a shallow femoral groove or abnormal alignment of the lower limb, can predispose individuals to patellar instability.
  • Previous Dislocations: Once a patellar dislocation has occurred, the risk of subsequent dislocations increases due to stretched or damaged stabilizing structures.

The symptoms of a patellar dislocation, where the kneecap (patella) moves out of its normal position within the groove of the femur (thigh bone), can vary in intensity depending on the severity of the dislocation.

Here are the common symptoms associated with a patellar dislocation:

  • Sudden & Severe Pain: The onset of pain is often sudden and can be intense. The pain is typically felt around the front of the knee, especially beneath or around the kneecap.
  • Visible Dislocation: In many cases, the kneecap is visibly displaced from its normal position within the knee joint. This may result in a noticeable bulge or deformity on the outer side of the knee.
  • Swelling & Bruising: Swelling around the kneecap can occur shortly after the dislocation, accompanied by bruising in the affected area due to bleeding under the skin.
  • Limited Movement: There may be difficulty moving the knee joint, particularly bending or straightening the leg. The discomfort and structural misalignment can hinder normal range of motion.
  • Inability to Bear Weight: Walking or putting weight on the affected leg can be extremely painful and challenging due to the instability & pain associated with the dislocated patella.
  • Feeling of Instability: Some individuals report a sensation of the knee “giving way” or feeling unstable, especially when attempting to move or bear weight on the affected leg.
  • Popping or Snapping Sensation: Some people experience a popping or snapping sensation at the time of the dislocation, often accompanied by an audible sound.
  • Tenderness to Touch: The area around the kneecap and the surrounding structures may be tender to touch.
  • Muscle Spasm: The muscles around the knee might contract or spasm in response to the dislocation, contributing to pain & discomfort.

It’s important to note that while these are common symptoms of a patellar dislocation, the severity always varies from person to person.

If you suspect a patellar dislocation or experience any of the above symptoms, it’s crucial to seek immediate medical attention. You can schedule an appointment with one of our orthopedic surgeons via this link or by calling our main office at: (908) 486-1111 today.